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11,600 | Early cerebral thromboembolic complications after radiofrequency catheter ablation of atrial fibrillation: incidence, characteristics, and risk factors. | Thromboembolic complications remain one of the most severe adverse events associated with catheter ablation of atrial fibrillation (AF), but data on such events are limited.</AbstractText>The purpose of this study was to evaluate the incidence, characteristics, and risk factors of thromboembolic complications after AF ablation.</AbstractText>Cerebral thromboembolic complications occurring within 1 month of 3360 consecutive AF radiofrequency catheter ablations were assessed. Stroke was defined as a neurologic deficit lasting more than 24 hours or with imaging study showing new infarction. Transient ischemic attack (TIA) was defined as a deficit lasting less than 24 hours and without documented infarction.</AbstractText>There were 17 peri-interventional cerebral thromboembolic events (0.5%). Nine cases (53%) were diagnosed as strokes and 8 (47%) as TIAs. Sixty percent of the events occurred within 48 hours after the ablation; the rest occurred within 1 week. In univariate analysis, peri-interventional thromboembolism was associated with peripheral vascular disease (P = .010), impaired left ventricular ejection fraction (P = .040), periprocedural bridging with heparin (P = .007), and previous stroke (P = .026). Multivariable analysis demonstrated that peripheral vascular disease (odds ratio [OR] 8.81, confidence interval [CI] 1.61-48.31, P = .012) and previous stroke (OR 6.13, CI 1.18-31.91, P = .031) were independent predictors. In a different model, the CHA2DS2-VASc score was associated with thromboembolism (OR 1.35, CI 1.00-1.80, P = .049).</AbstractText>Cerebral thromboembolic complications after AF radiofrequency catheter ablation are rare. They mostly occur within 48 hours after the procedure and remain without lasting neurologic deficits in the majority of cases. Such complications are associated with peripheral vascular disease, previous stroke, and the CHA2DS2-VASc score.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,601 | Vernakalant in an experimental model of pacing-induced heart failure: lack of proarrhythmia despite prolongation of repolarization. | The present ESC guidelines on atrial fibrillation have introduced vernakalant (VER) for pharmacologic cardioversion of atrial fibrillation. The aim of the present study was to investigate possible proarrhythmic effects of vernakalant in an experimental model of heart failure (HF).</AbstractText>In 12 female rabbits, HF was induced with the use of 4 weeks of rapid ventricular pacing. Twelve rabbits were sham operated. Isolated hearts demonstrated a significant prolongation of myocardial repolarization after induction of HF. Vernakalant caused a concentration-dependent (10 μmol/L and 30 μmol/L) increase of action potential duration (APD90) and QT interval without affecting spatial and temporal dispersion of repolarization. The increase in APD90 was accompanied by a greater increase in refractory period resulting in a significant increase in post-repolarization refractoriness. In control conditions, programmed ventricular stimulation and burst pacing led to ventricular fibrillation (VF) in 2 of the 12 sham (4 episodes) and in 3 of the 12 HF (24 episodes) subjects. In the presence of 30 μmol/L vernakalant, VF was no longer inducible in both groups (0 episodes). In the presence of low K+ concentration, neither sham nor HF vernakalant-treated subjects developed early after-depolarizations or ventricular tachyarrhythmias.</AbstractText>In the present study, application of vernakalant led to a significant prolongation of myocardial repolarization and increased post-repolarization refractoriness but did not induce early after-depolarization and therefore did not cause proarrhythmia in failing hearts.</AbstractText>Copyright © 2014 Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,602 | Lack of interference of electromagnetic navigation bronchoscopy to implanted cardioverter-defibrillator: in-vivo study. | Electromagnetic navigation bronchoscopy (ENB) (Superdimension) is a diagnostic and therapeutic tool in patients with lung lesions. Very small data are available about potential interference of ENB magnetic field to implanted cardioverter-defibrillators (ICDs) and any documentation of ICD behaviour if a ventricular tachyarrhythmia occurs during ENB is lacking. We tested a number of selected ICDs to assess if any interference occurs by ENB magnetic field on detection of clinical ventricular fibrillation and shock delivery.</AbstractText>Thirteen patients undergoing an ICD implantation or elective replacement with a clinical indication to assess the efficacy of defibrillation underwent: (i) real-time telemetric recording from ICD during ENB activation to detect possible noise; (ii) defibrillation test during exposure to ENB board-generated magnetic field. All tested ICDs showed no noise detection at maximum sensitivity level. Induced ventricular fibrillation was correctly detected and cured by implanted device. No change in programmed ICD parameters was induced by exposure to ENB magnetic field.</AbstractText>All tested ICDs correctly operated and rescued the patients from induced ventricular fibrillation during ENB. Electromagnetic navigation bronchoscopy appears to be safe in heart patients with an ICD; however, close cardiac monitoring of these patients during ENB must be ensured as correct behaviour of all existing ICDs can only be presumed from compliance of the manufacturer to International Standards which establish procedures for electromagnetic interference checking on implantable devices on different ranges of frequency.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
11,603 | Is the acetylcholine-regulated inwardly rectifying potassium current a viable antiarrhythmic target? Translational discrepancies of AZD2927 and A7071 in dogs and humans. | We aimed at examining the acetylcholine-dependent inward-rectifier current (IKAch) as a target for the management of atrial fibrillation (AF).</AbstractText>The investigative agents AZD2927 and A7071 concentration-dependently blocked IKACh in vitro with minimal off-target activity. In anaesthetized dogs (n = 17) subjected to 8 weeks of rapid atrial pacing (RAP), the left atrial effective refractory period (LAERP) was maximally increased by 50 ± 7.4 and 50 ± 4.8 ms following infusion of AZD2927 and A7071. Ventricular refractoriness and the QT interval were unaltered. During sustained AF, both drugs significantly reduced AF frequency and effectively restored sinus rhythm. AZD2927 successfully restored sinus rhythm at 10/10 conversion attempts and A7071 at 14/14 attempts, whereas saline converted 4/17 episodes only (P<0.001 vs. AZD2927 and A7071). In atrial flutter patients (n = 18) undergoing an invasive investigation, AZD2927 did not change LAERP, the paced QT interval, or ventricular refractoriness when compared with placebo. To address the discrepancy on LAERP by IKACh blockade in man and dog and the hypothesis that atrial electrical remodelling is a prerequisite for IKACh blockade being efficient, six dogs were studied after 8 weeks of RAP followed by sinus rhythm for 4 weeks to reverse electrical remodelling. In these dogs, both AZD2927 and A7071 were as effective in increasing LAERP as in the dogs studied immediately after the 8-week RAP period.</AbstractText>Based on the present series of experiments, an important role of IKACh in human atrial electrophysiology, as well as its potential as a viable target for effective management of AF, may be questioned.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
11,604 | Glucose fluctuations increase the incidence of atrial fibrillation in diabetic rats. | We investigated whether glucose fluctuations aggravate cardiac fibrosis and increase the occurrence of atrial fibrillation (AF) in rats with diabetes mellitus (DM).</AbstractText>Streptozotocin-induced diabetic rats were randomly divided into three groups: uncontrolled DM (U-STZ) group, controlled DM (C-STZ) group, and DM with glucose fluctuations (STZ-GF) group. Glucose fluctuations were induced by fasting for 24 h and additional regular insulin injections (0.5 IU/kg) administered three times per week for three consecutive weeks. C-STZ rats were administered long acting insulin (20 IU/kg) twice a day to control blood glucose levels. Cardiac fibrosis evaluated by Masson trichrome staining and the expressions of collagen type 1, collagen type 3, and α-smooth muscle actin were increased in U-STZ rats compared with C-STZ rats, which were more pronounced in STZ-GF rats. The inducibility of AF was significantly larger in U-STZ rats than C-STZ rats and was greatest in STZ-GF rats. To explore the mechanism of cardiac fibrosis, we investigated the levels of reactive oxygen species (ROS) and apoptosis. The expression of malondialdehyde, an indicator of ROS levels, was significantly upregulated in STZ-GF rats compared with U-STZ rats, along with increased thioredoxin-interacting protein (Txnip) expression in STZ-GF rats. Furthermore, caspase-3 expression and the number of TUNEL-positive cells were significantly increased in STZ-GF rats compared with U-STZ and C-STZ rats.</AbstractText>Glucose fluctuations increase the incidence of AF by promoting cardiac fibrosis. Increased ROS levels caused by upregulation of Txnip expression may be a mechanism whereby in glucose fluctuations induce fibrosis.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
11,605 | A prospective placebo controlled randomized study of caffeine in patients with supraventricular tachycardia undergoing electrophysiologic testing. | Patients with cardiac arrhythmias are generally instructed to avoid caffeine intake. A comprehensive evaluation of the electrophysiological effects of caffeine on atrial and ventricular tissues in humans has not previously been performed.</AbstractText>Eighty patients (31 men, mean age 49 ± 14 years) with symptomatic supraventricular tachycardia (SVT) undergoing an electrophysiologic study (EPS) prior to catheter ablation were randomized to receive oral caffeine or placebo. Caffeine at a dosage of 5 mg/kg (moderate intake) or placebo tablets were administered orally at a mean time of 57 ± 13 minutes prior to the EPS. The median (IQR) caffeine level in patients receiving caffeine was 7.4 μg/mL (4.7-8.7), as compared with 0.15 (0.00-0.61) in patients receiving placebo, P < 0.0001. Caffeine was associated with a significant increase in resting systolic and diastolic blood pressures as compared with placebo, while the resting heart rate was not significantly different between both groups. Caffeine was not associated with significant effects on the effective refractory period of the atrium or ventricle, as well as on AV node conduction. SVT was induced in all but 3 patients; there was no significant difference between groups receiving placebo or caffeine on SVT inducibility or the cycle length of induced tachycardias.</AbstractText>Caffeine, at moderate intake, was associated with significant increases in systolic and diastolic blood pressures, but had no evidence of a significant effect on cardiac conduction and refractoriness. Furthermore, no effect of caffeine on SVT induction or more rapid rates of induced tachycardias was found.</AbstractText>© 2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,606 | Acute Myocardial Infarction in Patient With Triple Negative Breast Cancer After Paclitaxel Infusion: A Case Report. | A 47-year-old woman with breast cancer suffered progressive chest pain and flushing within 5 minutes of her second exposure to paclitaxel. Her symptoms progressed and she became pulseless. Advanced cardiac life support (ACLS) was initiated, and after a series of chest compressions the cardiac monitor revealed ventricular fibrillation. With ongoing ACLS she was transferred to the emergency department where she regained a pulse. Review of electrocardiogram revealed prominent ST elevation in leads V1, V2 and V3 with reciprocal ST depression. She was transferred urgently to the catheterization laboratory. Angiography revealed a high-grade stenosis in the proximal left anterior descending artery (LAD), and drug-eluting stents were placed without complications. She was then transferred to the floor and shortly thereafter suffered pulseless electrical activity and died despite prolonged attempts at resuscitation. Herein, we describe the development of acute myocardial infarction after paclitaxel administration, discuss potential etiologies and review evidence for an allergic component. |
11,607 | Remote Monitoring for Follow-up of Patients with Cardiac Implantable Electronic Devices. | Follow-up of patients with cardiac implantable electronic devices is challenging due to the increasing number and technical complexity of devices coupled to increasing clinical complexity of patients. Remote monitoring (RM) offers the opportunity to optimise clinic workflow and to improve device monitoring and patient management. Several randomised clinical trials and registries have demonstrated that RM may reduce number of hospital visits, time required for patient follow-up, physician and nurse time, hospital and social costs. Furthermore, patient retention and adherence to follow-up schedule are significantly improved by RM. Continuous wireless monitoring of data stored in the device memory with automatic alerts allows early detection of device malfunctions and of events requiring clinical reaction, such as atrial fibrillation, ventricular arrhythmias and heart failure. Early reaction may improve patient outcome. RM is easy to use and patients showed a high level of acceptance and satisfaction. Implementing RM in daily practice may require changes in clinic workflow. To this purpose, new organisational models have been introduced. In spite of a favourable cost:benefit ratio, RM reimbursement still represents an issue in several European countries. |
11,608 | New Ablation Technologies and Techniques. | Catheter ablation is an established treatment strategy for a range of different cardiac arrhythmias. Over the past decade two major areas of expansion have been ablation of atrial fibrillation (AF) and ventricular tachycardia (VT) in the context of structurally abnormal hearts. In parallel with the expanding role of catheter ablation for AF and VT, multiple novel technologies have been developed which aim to increase safety and procedural success. Areas of development include novel catheter designs, novel navigation technologies and higher resolution imaging techniques. The aim of the present review is to provide an overview of novel developments in AF ablation and VT ablation in patients with of structural cardiac diseases. |
11,609 | Short QT Syndrome - Review of Diagnosis and Treatment. | Short QT syndrome (SQTS) is an inherited cardiac channelopathy characterised by an abnormally short QT interval and increased risk for atrial and ventricular arrhythmias. Diagnosis is based on the evaluation of symptoms (syncope or cardiac arrest), family history and electrocardiogram (ECG) findings. Mutations of cardiac ion channels responsible for the repolarisation orchestrate electrical heterogeneity during the action potential and provide substrate for triggering and maintaining of tachyarrhythmias. Due to the malignant natural history of SQTS, implantable cardioverter defibrillator (ICD) is the first-line therapy in affected patients. This review summarises current data and addresses the genetic basis and clinical features of SQTS. |
11,610 | Left atrial reverse remodeling and prevention of progression of atrial fibrillation with atrial resynchronization device therapy utilizing dual-site right atrial pacing in patients with atrial fibrillation refractory to antiarrhythmic drugs or catheter ablation. | Dual-site right atrial pacing (DAP) produces electrical atrial resynchronization but its long-term effect on the atrial mechanical function in patients with refractory atrial fibrillation (AF) has not been studied.</AbstractText>Drug-refractory paroxysmal (PAF) and persistent AF (PRAF) patients previously implanted with a dual-site right atrial pacemaker (DAP) with minimal ventricular pacing modes (AAIR or DDDR mode with long AV delay) were studied. Echocardiographic structural (left atrial diameter [LAD] and left ventricular [LV] end diastolic diameter [EDD], end systolic diameter [ESD]) and functional (ejection fraction [EF]) parameters were serially assessed prior to, after medium-term (n = 39) and long-term (n = 34) exposure to DAP.</AbstractText>During medium-term follow-up (n = 4.5 months), there was improvement in left atrial function. Mean peak A wave flow velocity increased with DAP as compared to baseline (75 ± 19 vs. 63 ± 23 cm/s, p = 0.003). The long-term impact of DAP was studied with baseline findings being compared with last follow-up data with a mean interval of 37 ± 25 (range 7-145) months. Mean LAD declined from 45 ± 5 mm at baseline to 42 ± 7 mm (p = 0.003). Mean LVEF was unchanged from 52 ± 9 % at baseline and 54 ± 6 % at last follow-up (p = 0.3). There was no significant change in LV dimensions with mean LVEDD being 51 ± 6 mm at baseline and 53 ± 5 mm at last follow-up (p = 0.3). Mean LVESD also remained unchanged from 35 ± 6 mm at baseline to 33 ± 6 mm at last follow-up (p = 0.47). During long-term follow-up, 30 patients (89 %) remained in sinus or atrial paced rhythm as assessed by device diagnostics at 3 years.</AbstractText>DAP can achieve long-term atrial reverse remodeling and preserve LV systolic function. DAP when added to antiarrhythmic drug (AAD) and/or catheter ablation (ABL) maintains long-term rhythm control and prevents AF progression in elderly refractory AF patients. Reverse remodeling with DAP may contribute to long-term rhythm control.</AbstractText> |
11,611 | Cardiocerebral Resuscitation: An Approach to Improving Survival of Patients With Primary Cardiac Arrest. | Out-of-hospital cardiac arrest (OHCA) is a major public health problem. In the United States, OHCA accounts for more premature deaths than any other cause. For over a half-century, the national "Guidelines" for resuscitation have recommended the same initial treatment of primary and secondary cardiac arrests. Using this approach, the overall survival of patients with OHCA, while quite variable, was generally very poor. One reason is that the etiologies of cardiac arrests are not all the same. The vast majority of nontraumatic OHCA in adults are due to a "primary" cardiac arrest, rather than secondary to respiratory arrest. Decades of research and ongoing reviews of the literature led the University of Arizona Sarver Heart Center Resuscitation Research Group to conclude in 2003 that the national guidelines for patients with primary cardiac arrest were not optimal. Therefore, we instituted a new, nonguidelines approach to the therapy of primary cardiac arrest that dramatically improved survival. We called this approach cardiocerebral resuscitation (CCR), as it is the heart and the brain that are the most vulnerable and therefore need to be the focus of resuscitation efforts for these patients. In contrast, cardiopulmonary resuscitation should be reserved for respiratory arrests. Cardiocerebral resuscitation evolved into 3 components: the community, with emphasis for lay individuals to "Check, Call, Compress" and use an automated external defibrillator if available; the Emergency Medical Services, that emphasizes delayed intubation in favor of passive ventilation, urgent and near continuous chest compressions before and immediately after a single indicated shock, and the early administration of epinephrine; and the third component, added in 2007, the designations of hospitals in Arizona that request this designation and agree to receive patients with return of spontaneous circulation following OHCA and to institute state-of-the-art postresuscitation care that includes urgent therapeutic mild hypothermia and cardiac catheterization as a Cardiac Receiving Center. Each component of CCR is critical for optimal survival of patients with primary OHCA. In each city, county, and state where CCR was instituted, the result was a marked increase in survival of the subgroup of patients with OHCA most likely to survive, for example, those with a shockable rhythm. The purpose of this invited article on CCR is to review this alternative approach to resuscitation of patients with primary cardiac arrest and to encourage its adoption worldwide so that more lives can be saved. |
11,612 | Acute cardiogenic pulmonary edema--etiological spectrum and precipitating factors. | The analysis of the predisposing and precipitating factors encountered in the anamnesis of the patients hospitalized with acute pulmonary oedema, in order to establish some correlations with the evolution and prognosis.</AbstractText>The study included 50 patients, 32 males and 18 females, admitted to the Cardiology I Clinic between 2009 and 2013, diagnosed with acute pulmonary oedema upon admission. The following aspects were investigated: cardiovascular antecedents, prodromal elements of the current episode of acute pulmonary oedema (APE), risk factors and associated co morbidities, previous treatments followed at home as well as the triggering factors of the acute episode.</AbstractText>The main pathology on which the acute pulmonary oedema (APE) episode occurred was represented by: arterial high blood pressure (HBP), dilated cardiomyopathy, ischemic heart disease, valvular heart disease, pre-existing atrial rhythm disorders. The analysis of the factors that precipitated the acute pulmonary oedema episode revealed the following possible triggering conditions: inadequate physical effort on the background of treatment discontinuation, high sodium diet, a prolonged ischemic episode due to inadequate physical effort, rhythm disorder with rapid ventricular response (atrial fibrillation, atrial flutter). In some cases, the risk factors were cumulated.</AbstractText>Acute pulmonary oedema represents a major emergency that requires immediate admission to hospital and rapid treatment in the emergency department concurrent with the identification of the triggering and precipitating factors.</AbstractText> |
11,613 | [Ventricular fibrillation or general seizure?]. | A 78-year-old patient seemed to have recurrent seizures due to marginal hypoglycaemia. He was initially awake with stable circulation. Subsequently, he lost consciousness followed by extensie twitching arms of his arms and the upper part of his body. Thereafter, the patient was somnolent, but accessible.</AbstractText>Initially hypoglycemia was thought to have caused general seizures. But the ECG monitor showed repetitive ventricular fibrillation, which was terminated by a cardioverter-defibrillator that had been implanted 3 years previously because of dilatative cardiomyopathy. At admission to hospital, marked hypokalemia (1,8 mmol/l) was noted as the cause of ventricular fibrillation. After normalization of serum potassium no further events occurred.</AbstractText>Disorders of consciousness always request an ECG for early diagnosis.</AbstractText>© Georg Thieme Verlag KG Stuttgart · New York.</CopyrightInformation> |
11,614 | Role of primary care physicians in treating patients with ST-segment elevation myocardial infarction located in remote areas (from the REseau Nord-Alpin des Urgences [RENAU], Network). | European guidelines for ST-segment elevation myocardial infarction (STEMI) encourage healthcare networks to increase rates of, and decrease delays to, reperfusion. We examined the impact of training primary care physicians (PCPs) to use equipment for pre-hospital management of STEMI patients in remote areas.</AbstractText>A network for cardiac emergencies was set up in the French Northern Alps in 2002 and a registry of STEMI patients has been kept since. In 2005, 24 local volunteer PCPs were trained and equipped with electrocardiograms, fibrinolysis kits, and automated external defibrillators to deal with cardiac emergencies in remote areas (>30-minute ambulance travelling time). In this study, when the central call dispatcher received a telephone call from a patient in a remote area reporting chest pain with a high probability of STEMI, the dispatcher sent a mobile intensive care unit (MICU) with an emergency physician on board and asked the local PCP, if available, to manage the patient while awaiting arrival of the MICU. Patients in whom the diagnosis of STEMI was confirmed were taken by MICU to an interventional cardiology hospital. We report on patients who received care from a PCP before arrival of the MICU. Between 2005 and 2010, 4,015 patients were enrolled in the registry; 180 patients were located in a remote area, of whom 140 were in an area covered by a participating PCP. Of the 62 patients attended by a PCP before MICU arrival, 27 received thrombolysis and eight patients with ventricular tachycardia/fibrillation were shocked with an automated external defibrillator by the PCP. Mean times from telephone call to thrombolysis were shorter when the patient was attended by a PCP (45.0 ± 25.5 vs 62.4 ± 23.4 min without intervention; p = 0.003). STEMI diagnosis without contraindication to thrombolysis was confirmed in 26 of 27 patients treated as such by PCPs and 1 patient was diagnosed with a Tako-Tsubo syndrome.</AbstractText>PCP care of STEMI patients located in isolated areas appears efficient, with high rates of resuscitation and thrombolysis and a shorter delay to reperfusion.</AbstractText>© The European Society of Cardiology 2014.</CopyrightInformation> |
11,615 | Implication of left ventricular diastolic dysfunction in cryptogenic ischemic stroke. | Left ventricular diastolic dysfunction (LVDD) is a predictor for atrial fibrillation (AF). This study was aimed to investigate whether LVDD in cryptogenic ischemic stroke (CS) could be a clue to stroke mechanism.</AbstractText>The clinical and echocardiographic findings of 1589 consecutive patients with acute ischemic stroke or transient ischemic attack between 2004 and 2013 were reviewed. LVDDs among stroke subtypes were graded by transthoracic echocardiography into 4 groups by severity: normal, abnormal relaxation (grade I), pseudonormal (grade II), and restrictive diastolic filling (grade III), whereas severe LVDD was defined as grade III. We classified the lesion pattern of CS into cardioembolism-mimic or non-cardioembolism-mimic and determined whether cardioembolism-mimic lesions were associated with severe LVDD.</AbstractText>The fraction of severe LVDD in CS was not different from that of stroke with AF (27.3% versus 37.1%; P=0.173) but was significantly higher than that of stroke without AF (27.3% versus 13.4%; P=0.008). Cardioembolism-mimic CS had more severe LVDD than non-cardioembolism-mimic CS (41.4% versus 11.5%; P=0.013). LVDD of grade II (odds ratio, 4.37; 95% confidence interval, 2.99-6.41) and grade III (odds ratio, 5.60; 95% confidence interval, 3.42-9.17) were independently related to stroke with AF after adjusting covariates.</AbstractText>The severe LVDD could be a predictor of stroke with AF, and its frequency was similar between CS and stroke with AF. Cardioembolism-mimic CS had significantly more severe LVDD than non-cardioembolism-mimic CS. LVDD could be helpful to discriminate the stroke mechanism in the patients with acute CS.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,616 | Advances in clinical cardiology. | Multiple, potentially practice-changing cardiology trials have been presented or published over the past year. In this paper, we summarize and place in clinical context, new data regarding management of acute coronary syndrome and ST-elevation myocardial infarction (copeptin assessment, otamixaban, cangrelor, prasugrel, sodium nitrite, inclacumab, ranolazine, preventive coronary intervention of non-culprit lesions, immediate thrombolytic therapy versus transfer for primary intervention), new coronary intervention data (thrombectomy, radial access, pressure wire fractional flow reserve, antiplatelet therapy duration and gene-guidance, permanent and biodegradable polymers, coronary bifurcation and strategies), and coronary artery bypass data (off pump vs. on pump). Latest trials in trans-aortic valve implantation, heart failure (eplerenone, aliskiren, spironolactone, sildenafil, dopamine, nesiritide, omecamtiv mecarbil, the algisyl left ventricular augmentation device, and echo-guided cardiac resynchronization), atrial fibrillation (edoxaban, dabigatran, and ablation), cardiac arrest (hypothermia, LUCAS™ mechanical chest compression), and cardiovascular prevention (vitamins, renal denervation for resistant hypertension, renal artery stenting, saxagliptin, alogliptin, and gastric banding) are also discussed. |
11,617 | Application of positron emission tomography in the detection of myocardial metabolism in pig ventricular fibrillation and asphyxiation cardiac arrest models after resuscitation. | To study the application of positron emission tomography (PET) in detection of myocardial metabolism in pig ventricular fibrillation and asphyxiation cardiac arrest models after resuscitation.</AbstractText>Thirty-two healthy miniature pigs were randomized into a ventricular fibrillation cardiac arrest (VFCA) group (n=16) and an asphyxiation cardiac arrest (ACA) group (n=16). Cardiac arrest (CA) was induced by programmed electric stimulation or endotracheal tube clamping followed by cardiopulmonary resuscitation (CPR) and defibrillation. At four hours and 24 h after spontaneous circulation was achieved, myocardial metabolism was assessed by PET. 18F-FDG myocardial uptake in PET was analyzed and the maximum standardized uptake value (SUVmax) was measured.</AbstractText>Spontaneous circulation was 100% and 62.5% in VFCA group and ACA group, respectively. PET demonstrated that the myocardial metabolism injuries was more severe and widespread after ACA than after VFCA. The SUVmax was higher in VFCA group than in ACA group (P<0.01). In VFCA group, SUVmax at 24 h after spontaneous circulation increased to the level of baseline.</AbstractText>ACA causes more severe cardiac metabolism injuries than VFCA. Myocardial dysfunction is associated with less successful resuscitation. Myocardial stunning does occur with VFCA but not with ACA.</AbstractText>Copyright © 2014 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.</CopyrightInformation> |
11,618 | Continuous rhythm monitoring for ventricular arrhythmias after alcohol septal ablation for hypertrophic cardiomyopathy. | The purpose of the present study was to determine the incidence of ventricular arrhythmias before and after alcohol septal ablation (ASA).</AbstractText>In patients with hypertrophic obstructive cardiomyopathy (HOCM), gradient reduction by ASA is an alternative for surgical myectomy. However, concerns exist about whether the induction of a myocardial scar during ASA may create substrate for ventricular arrhythmias.</AbstractText>The study group consisted of 44 patients in whom ASA was performed for symptomatic, drug-refractory hypertrophic cardiomyopathy. Continuous rhythm monitoring was obtained by implantable loop recorder (n=30) or pacemaker (n=14). Occurrence of ventricular and supraventricular arrhythmias before and after ASA was noted, retrospectively.</AbstractText>The ASA procedure was considered successful (resting gradient <30 mm Hg, and provoked gradient <50 mm Hg at 4 months in combination with NYHA Class functional status ≤2) in 30 (68%) patients. Rhythm monitoring before ASA was available in 28 patients. The median duration of rhythm monitoring after ASA was 3.0 years (IQR 1.3-4.3). Sustained VT/VF within 30 days after ASA occurred in three patients (7%), including 2 cases of procedural VF, while no VT/VF was observed before ASA (p=0.10). No sustained VT/VF was observed >30 days after ASA. No cardiac deaths occurred during follow-up.</AbstractText>In a low-risk cohort of patients who underwent ASA, in which continuous rhythm monitoring was performed, sustained VT or VF within 30 days occurred in 3 patients (7%) while no VT/VF was observed before ASA. During long-term follow-up, no sustained VT or VF was observed >30 days after ASA.</AbstractText>Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.</CopyrightInformation> |
11,619 | Treatment of methadone-induced torsades de pointes with lidocaine. | Methadone maintenance treatment (MMT) is commonly used for chronic pain control and for substitution in heroin addicts undergoing rehabilitation. Methadone is known to prolong QT interval and sometimes cause torsade de pointes (TdP) and ventricular fibrillation (VF). Treatment of TdP by antiarrhythmic drugs that prolong QT interval may worsen TdP. To our knowledge, worsening of methadone-induced TdP by amiodarone has not been reported before. We describe here a case of methadone-induced TdP that deteriorated into ventricular fibrillation upon treatment with intravenous (IV) amiodarone and resolved after discontinuation of amiodarone and treatment with IV magnesium, potassium, and lidocaine. |
11,620 | Mid-term follow-up after maze IV procedures for concomitant atrial fibrillation. | We performed a retrospective analysis of the maze IV procedures performed in our surgical department for concomitant atrial fibrillation.</AbstractText>Preoperative, in-hospital and postoperative follow-up data were collected from 46 consecutive patients who underwent the maze IV operation between April 2006 and December 2010. All electrocardiograms and Holters were reviewed.</AbstractText>One patient died in-hospital. During a mean follow-up of 25 +/- 16.3 months seven patients died: two related to a hemorrhagic stroke, one due to right ventricular failure, the remainder deaths were not cardiac related. The success rate, defined as no recurrence of AF or atrial flutter with a blanking period of 6 months postoperatively, was 73.7%. Plots of probability of freedom of atrial fibrillation over time are drawn and reach a stable level after one year.</AbstractText>The mid term results of the maze IV procedures for concomitant atrial fibrillation are very good. The results are stable for the remainder of follow-up.</AbstractText> |
11,621 | Coronary artery spasm following off-pump coronary artery bypass surgery. | Coronary artery spasm after coronary artery bypass surgery may result in life-threatening arrhythmias, circulatory collapse, or death. We report two cases of coronary artery spasm after coronary artery bypass surgery, one of which developed ventricular fibrillation requiring extracorporeal membrane oxygenation support. Both patients were discharged in good condition and are currently followed as outpatients. Unexpected sudden hemodynamic compromise could be due to coronary vasospasm, and this should be considered as one of the possible differential diagnoses. We were able to prevent the lethal consequences seen with coronary artery spasm by early diagnosis and management. |
11,622 | Sevoflurane therapy for life-threatening acute severe asthma: a case report. | Acute severe asthma is a life-threatening form of bronchial constriction in which the progressively worsening airway obstruction is unresponsive to the usual appropriate bronchodilator therapy. Pathophysiological changes restrict airflow, which leads to premature closure of the airway on expiration, impaired gas exchange, and dynamic hyperinflation ("air-trapping"). Additionally, patients suffering from asthma for a prolonged period of time usually have serious comorbidities. These conditions constitute a challenge during the treatment of this disease. Therapeutic interventions are designed to reduce airway resistance and improve respiratory status. To achieve therapeutic goals, appropriate bronchodilator treatment is indispensable, and mechanical ventilation under adequate sedation may also be required. The volatile anesthetic agent, sevoflurane, meets both criteria; therefore, its use can be beneficial and should be considered.</AbstractText>A 67-yr-old Caucasian male presented with acute life-threatening asthma provoked by an assumed upper airway infection and non-steroidal anti-inflammatory drug antipyretics, complicated by chronic atrial fibrillation and hemodynamic instability. Due to frequent premature ventricular contractions, conventional treatment was considered unsafe and discontinued, and sevoflurane inhalation was initiated via the AnaConDa (Anaesthetic Conserving Device). Symptoms of life-threatening bronchospasm resolved, and the patient's respiratory status improved within hours. Adequate sedation was also achieved without any hemodynamic adverse effects.</AbstractText>The volatile anesthetic agent, sevoflurane, is used widely in anesthesia practice. Its utility for treatment of refractory bronchospasm has been appreciated for years; however, its administration was difficult within the environment of the intensive care unit due to the need for an anesthesia machine and a scavenging system. The introduction of the AnaConDa eliminates these obstacles and makes the use of sevoflurane safe and simple. Our case report reveals the potential of sevoflurane as a "two-in-one" (bronchodilator and sedative) drug to treat a severe acute asthma attack.</AbstractText> |
11,623 | [Analysis of the cardiac side effects of antipsychotics: Japanese Adverse Drug Event Report Database (JADER)]. | We analyzed the cases of side effects due to antipsychotics reported to Japan's Pharmaceuticals and Medical Devices Agency (PMDA) from Jan. 2004 to Dec. 2012. We used the Japanese Adverse Drug Event Report Database (JADER) and analyzed 136 of 216,945 cases using the defined terms. We also checked the cardiac adverse effects listed in the package inserts of the antipsychotics involved. We found cases of Ikr blockade resulting in sudden death (49 cases), electrocardiogram QT prolonged (29 cases), torsade de pointes (TdP, 19 cases), ventricular fibrillation (VF, 10 cases). M2 receptor blockade was observed in tachycardia (8 cases) and sinus tachycardia (3 cases). Calmodulin blockade was involved in reported cardiomyopathy (3 cases) and myocarditis (1 case). Multiple adverse events were reported simultaneously in 14 cases. Our search of package inserts revealed warnings regarding electrocardiogram QT prolongation (24 drugs), tachycardia (23), sudden death (18), TdP (14), VF (3), myocarditis (1) and cardiomyopathy (1). We suggest that when an antipsychotic is prescribed, the patient should be monitored regularly with ECG, blood tests, and/or biochemical tests to avoid adverse cardiac effects. |
11,624 | Ventricular fibrillation mechanisms and cardiac restitutions: An investigation by simulation study on whole-heart model. | The action potential duration (APD) and the conduction velocity (CV) restitution have been reported to be important in the maintenance and conversion of ventricular fibrillation (VF), whose mechanisms remain poorly understood. Multiple-wavelet and/or mother-rotor have been regarded as the main VF mechanisms, and APD restitution (APDR) and CV restitution (CVR) properties are involved in the mutual conversion or transition between VF and ventricular tachycardia (VT).</AbstractText>The effects of APDR (both its slope and heterogeneity) and CVR on VF organization and conversion were examined using a "rule-based" whole-heart model. The results showed that different organizations of simulated VF were manifestations of different restitution configurations. Multiple-wavelet and mother-rotor VF mechanisms could recur in models with steep and heterogeneous APDR, respectively. Suppressing the excitability either decreased or increased the VF complexity under the steep or shallow APDR, respectively. The multiple-wavelet VF changed into a VT in response to a flattening of the APDR, and the VT degenerated into a mother-rotor VF due to the APDR heterogeneity.</AbstractText>Our results suggest that the mechanisms of VF are tightly related to cardiac restitution properties. From a viewpoint of the "rule-based" whole-heart model, our work supports the hypothesis that the synergy between APDR and CVR contributes to transitions between multiple-wavelet and mother-rotor mechanisms in the VF.</AbstractText>Copyright © 2014 Elsevier Ltd. All rights reserved.</CopyrightInformation> |
11,625 | Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II: rationale and design of the ORBIT-AF II registry. | Recent clinical trials have demonstrated the safety and efficacy of several non-vitamin K oral anticoagulants (NOACs) for the treatment of atrial fibrillation (AF). However, there are limited data on their use and outcomes in routine clinical practice, particularly among patients newly diagnosed as having AF and patients with AF recently transitioned to a NOAC.</AbstractText><AbstractText Label="METHODS/DESIGN" NlmCategory="METHODS">ORBIT-AF II is a multicenter, national registry of patients with AF that is enrolling up to 15,000 newly diagnosed patients with AF and/or those with AF recently transitioned to a NOAC from 300 US outpatient practices. These patients will be followed for up to 2 years, including clinical status, outcomes (major adverse cardiovascular events, bleeding), and management of anticoagulation surrounding bleeding events. In addition, detailed data regarding the use of these agents in and around cardiac procedures, their complications, and management of such complications will be collected.</AbstractText>The ORBIT-AF II registry will provide valuable insights into the safety and effectiveness of NOACs used in AF in community practice settings.</AbstractText>Copyright © 2014 Mosby, Inc. All rights reserved.</CopyrightInformation> |
11,626 | Obesity does not increase complication rate of percutaneous epicardial access. | Percutaneous epicardial access for ablative therapies is an increasingly common technique utilized for refractory ventricular arrhythmias. There are, however few known data on obesity and complication rates associated with this procedure.</AbstractText>We retrospectively reviewed the charts of subjects undergoing epicardial access at Mayo Clinic between January 2004 and June 2013. Baseline clinical and echocardiographic data were collected for each subject, who was then classified into body mass index (BMI) categories as underweight, normal weight, overweight, and obese based on a BMI of <18.5, 18.5-24.99, 25-29.99, and ≥30, respectively. Events and complications were recorded, and procedural and clinical success rates were determined. There was no statistically significant difference in access approach, procedural or clinical outcomes, or complications among the BMI categories. Note that 95.1%, 91.7%, and 93.1% derived procedural success among the normal weight, overweight, and obese categories, respectively (P value = 0.81). Similarly, there was no difference in clinical outcomes with success rates of 68.3%, 66.7%, and 75.9% between the respective groups (P value = 0.54). At 5 years, there was a trend toward increased mortality among obese individuals (28.8%) compared to normal weight (8.8%) and overweight (9.8%) patients (P value = 0.139).</AbstractText>Percutaneous epicardial access, mapping, and ablation can be performed in obese individuals with similar outcomes to those of lower weight category. Obesity should not preclude the use of percutaneous epicardial access when clinically indicated.</AbstractText>© 2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,627 | Fosinopril improves the electrophysiological characteristics of left ventricular hypertrophic myocardium in spontaneously hypertensive rats. | This study investigated the effects of fosinopril on the electrophysiological characteristics of the left ventricular hypertrophic myocardium in spontaneously hypertensive rats (SHRs). Twenty-four 10-week-old male SHRs were divided into fosinopril and non-fosinopril groups (n = 12 each). Twelve 10-week-old Wistar-Kyoto rats were used a control group. Left ventricular mass index and ventricular fibrillation threshold (VFT) were measured after 8 weeks of fosinopril or saline treatment. L-type calcium current (I CaL), sodium current (I Na), and transient outward potassium current (I to) were measured in left ventricular myocytes after 8 weeks of fosinopril or saline treatment using the whole-cell patch-clamp technique. VFT was higher in the fosinopril group than in the non-fosinopril group (17.5 ± 1.2 mA vs. 15.6 ± 1.1 mA, P < 0.01). The density of I CaL was lower in the fosinopril group than in the non-fosinopril group (-7.17 ± 0.13 pA/pF vs. -7.87 ± 0.13 pA/pF, P < 0.05). The density of I to was higher in the fosinopril group than in the non-fosinopril group (14.46 ± 0.28 pA/pF vs. 12.66 ± 0.25 pA/pF, P < 0.05). I to was positively correlated with VFT (r = 0.90, P < 0.001) and was found to be associated independently with VFT (P < 0.001). Fosinopril improves the electrophysiological characteristics of the left ventricular hypertrophic myocardium in SHRs. |
11,628 | Initial complications and factors related to prehospital mortality in acute myocardial infarction with ST segment elevation. | Hospital mortality in myocardial infarction ST-elevation myocardial infarction has decreased in recent years, in contrast to prehospital mortality. Our objective was to determine initial complications and factors related to prehospital mortality in patients with acute myocardial infarction with ST segment elevation (STEMI).</AbstractText>Observational study based on a prospective continuous register of patients of any age attended by out-of-hospital emergency teams in Andalusia between January 2006 and June 2009. This includes patients with acute coronary syndrome-like symptoms whose initial ECG showed ST elevation or presumably new left bundle branch block (LBBB). Epidemiological, prehospital data and final diagnostic were recorded. The study included all patients with STEMI on the register, without age restrictions. Forward stepwise logistic regression analysis was performed to control for confounders.</AbstractText>A total of 2528 patients were included, 24% were women. Mean age 63.4±13.4 years; 16.7% presented atypical clinical symptoms. Initial complications: ventricular fibrillation (VF) 8.4%, severe bradycardia 5.8%, third-degree atrial-ventricular (AV) block 2.4% and hypotension 13.5%. Fifty-two (2.1%) patients died before reaching hospital. Factors associated with prehospital mortality were female sex (OR 2.36, CI 1.28 to 4.33), atypical clinical picture (OR 2.31, CI 1.21 to 4.41), hypotension (OR 4.95, CI 2.60 to 9.20), LBBB (OR 4.29, CI 1.71 to 10.74), extensive infarction (ST elevation in ≥5 leads) (OR 2.53, CI 1.28 to 5.01) and VF (OR 2.82, CI 1.38 to 5.78).</AbstractText>A significant proportion of patients with STEMI present early complications in the prehospital setting, and some die before reaching hospital. Prehospital mortality was associated with female sex and atypical presentation, as pre-existing conditions, and hypotension, extensive infarction, LBBB and VF on emergency team attendance.</AbstractText>Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.</CopyrightInformation> |
11,629 | Sudden cardiac arrest in takotsubo cardiomyopathy - a case study. | We present a 59-year-old woman who was admitted to hospital after sudden cardiac arrest due to ventricular fibrillation. Finally takotsubo syndrome was diagnosed. In the acute phase of takotsubo syndrome life-threatening ventricular arrhythmias and significant hemodynamic disorders may occur due to strong adrenergic stimulation and myocardial ischemia. It has been proved that the occurrence of torsade de pointes tachycardia in the acute phase of takotsubo cardiomyopathy is associated with QT prolongation. There are no clear guidelines on pharmacological treatment and implantable cardioverter defibrillator implantation after a past takotsubo episode. Takotsubo cardiomyopathy has not been entirely explained as an etiological disease. |
11,630 | Ventilation/perfusion ratios measured by multiple inert gas elimination during experimental cardiopulmonary resuscitation. | During cardiopulmonary resuscitation (CPR) the ventilation/perfusion distribution (VA /Q) within the lung is difficult to assess. This experimental study examines the capability of multiple inert gas elimination (MIGET) to determine VA /Q under CPR conditions in a pig model.</AbstractText>Twenty-one anaesthetised pigs were randomised to three fractions of inspired oxygen (1.0, 0.7 or 0.21). VA/ Q by micropore membrane inlet mass spectrometry-derived MIGET was determined at baseline and during CPR following induction of ventricular fibrillation. Haemodynamics, blood gases, ventilation distribution by electrical impedance tomography and return of spontaneous circulation were assessed. Intergroup differences were analysed by non-parametric testing.</AbstractText>MIGET measurements were feasible in all animals with an excellent correlation of measured and predicted arterial oxygen partial pressure (R(2)  = 0.96, n = 21 for baseline; R(2)  = 0.82, n = 21 for CPR). CPR induces a significant shift from normal VA /Q ratios to the high VA /Q range. Electrical impedance tomography indicates a dorsal to ventral shift of the ventilation distribution. Diverging pulmonary shunt fractions induced by the three inspired oxygen levels considerably increased during CPR and were traceable by MIGET, while 100% oxygen most negatively influenced the VA /Q. Return of spontaneous circulation were achieved in 52% of the animals.</AbstractText>VA /Q assessment by MIGET is feasible during CPR and provides a novel tool for experimental purposes. Changes in VA /Q caused by different oxygen fractions are traceable during CPR. Beyond pulmonary perfusion deficits, these data imply an influence of the inspired oxygen level on VA /Q. Higher oxygen levels significantly increase shunt fractions and impair the normal VA /Q ratio.</AbstractText>© 2014 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.</CopyrightInformation> |
11,631 | Optimal blood pressure in patients with atrial fibrillation (from the AFFIRM Trial). | Many medications used to treat atrial fibrillation (AF) also reduce blood pressure (BP). The relation between BP and mortality is unclear in patients with AF. We performed a post hoc analysis of 3,947 participants from the Atrial Fibrillation Follow-Up Investigation of Rhythm Management trial. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) at baseline and follow-up were categorized by 10-mm Hg increments. The end points were all-cause mortality (ACM) and secondary outcome (combination of ACM, ventricular tachycardia and/or fibrillation, pulseless electrical activity, significant bradycardia, stroke, major bleeding, myocardial infarction, and pulmonary embolism). SBP and DBP followed a "U-shaped" curve with respect to primary and secondary outcomes after multivariate analysis. A nonlinear Cox proportional hazards model showed that the incidence of ACM was lowest at 140/78 mm Hg. Subgroup analyses revealed similar U-shaped curves. There was an increased ACM observed with BP <110/60 mm Hg (hazard ratio 2.4, p <0.01, respectively, for SBP and DBP). In conclusion, in patients with AF, U-shaped relation existed between BP and ACM. These data suggest that the optimal BP target in patients with AF may be greater than the general population and that pharmacologic therapy to treat AF may be associated with ACM or adverse events if BP is reduced to <110/60 mm Hg. |
11,632 | Influence of the mode of management of acute myocardial infarction on the inducibility of ventricular tachyarrhythmias with programmed ventricular stimulation after myocardial infarction. | Programmed ventricular stimulation (PVS) is a technique for screening patients at risk for ventricular tachycardia (VT) after myocardial infarction (MI), but the results might be difficult to interpret.</AbstractText>To investigate the results of PVS after MI, according to date of completion.</AbstractText>PVS results were interpreted according to the mode of MI management in 801 asymptomatic patients: 301 (group I) during the period 1982-1989, 315 (group II) during 1990-1999, and 185 (group III) during 2000-2010. The periods were chosen based on changes in MI management. Angiotensin-converting enzyme (ACE) inhibitors had been given since 1990; primary angioplasty was performed routinely since 2000. The PVS protocol was the same throughout the whole study period.</AbstractText>Group III was older (61 +/- 11 years) than groups I (56 +/- 11) and II (58 +/- 11) (P < 0.002). Left ventricular ejection fraction (LVEF) was lower in group III (36.5 +/- 11%) than in groups I (44 +/- 15) and II (41 +/- 12) (P < 0.000). Monomorphic VT < 270 beats/min was induced as frequently in group III (28%) as in group II (22.5%) but more frequently than in group I (20%) (P < 0.03). Ventricular fibrillation and flutter (VF) was induced less frequently in group III (14%) than in groups I (28%) (P < 0.0004) and II (30%) (P < 0.0000). Low left ventricular ejection fraction (LVEF) and date of inclusion (before/after 2000) were predictors of VT or VF induction on multivariate analysis.</AbstractText>Induction of non-specific arrhythmias (ventricular flutter and fibrillation) was less frequent than before 2000, despite the indication of PVS in patients with lower LVEF. This decrease could be due to the increased use of systematic primary angioplasty for MI since 2000.</AbstractText> |
11,633 | Detection of T-wave beat-by-beat variations prior to ventricular arrhythmias onset in ICD-stored intracardiac electrograms: the Endocardial T-Wave Alternans Study (ETWAS). | The aim of the Endocardial T-Wave Alternans Study was to prospectively assess the presence of T-wave alternans (TWA) or beat-to-beat repolarization changes on implantable cardioverter-defibrillator (ICD)-stored electrograms (EGMs) immediately preceding the onset of spontaneous ventricular tachycardia (VT) or fibrillation (VF).</AbstractText>Thirty-seven VT/VF episodes were compared to 116 baseline reference EGMs from the same 57 patients. A Bayesian model was used to estimate the T-wave waveform in each cardiac beat and a set of 10 parameters was selected to segment each detected T wave. Beat-by-beat differences in each T-wave parameter were computed using the absolute value of the difference between each beat and the following one. Fisher criterion was used for determining the most discriminant T-wave parameters, then top-M ranked parameters yielding a normalized cumulative Fisher score > 95% were selected, and analysis was applied on these selected parameters. Simulated TWA EGMs were used to validate the algorithm.</AbstractText>In the simulation study, TWA was detectable even in the case of the smallest simulated alternans of 25 μV. In 13 of the 37 episodes (35%) occurring in nine of 16 patients, significant larger beat-to-beat variations before arrhythmia onset were detected compared to their respective references (median one positive episode per patient). Parameters including the T-wave apex amplitude seem the more discriminant parameters.</AbstractText>Detection of beat-by-beat repolarization variations in ICD-stored EGMs is feasible in a significant subset of cases and may be used for predicting the onset of ventricular arrhythmias.</AbstractText>©2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,634 | Regression of electrocardiographic left ventricular hypertrophy or strain is associated with lower incidence of cardiovascular morbidity and mortality in hypertensive patients independent of blood pressure reduction - A LIFE review. | Cornell product criteria, Sokolow-Lyon voltage criteria and electrocardiographic (ECG) strain (secondary ST-T abnormalities) are markers for left ventricular hypertrophy (LVH) and adverse prognosis in population studies. However, the relationship of regression of ECG LVH and strain during antihypertensive therapy to cardiovascular (CV) risk was unclear before the Losartan Intervention for Endpoint Reduction in Hypertension (LIFE) study. We reviewed findings on ECG LVH regression and strain over time in 9193 hypertensive patients with ECG LVH at baseline enrolled in the LIFE study. The composite endpoint of CV death, nonfatal MI, or stroke occurred in 1096 patients during 4.8±0.9years follow-up. In Cox multivariable models adjusting for randomized treatment, known risk factors including in-treatment blood pressure, and for severity ECG LVH by Cornell product and Sokolow-Lyon voltage, baseline ECG strain was associated with a 33% higher risk of the LIFE composite endpoint (HR. 1.33, 95% CI [1.11-1.59]). Development of new ECG strain between baseline and year-1 was associated with a 2-fold increased risk of the composite endpoint (HR. 2.05, 95% CI [1.51-2.78]), whereas the risk associated with regression or persistence of ECG strain was attenuated and no longer statistically significant (both p>0.05). After controlling for treatment with losartan or atenolol, for baseline Framingham risk score, Cornell product, and Sokolow-Lyon voltage, and for baseline and in-treatment systolic and diastolic blood pressure, 1 standard deviation (SD) lower in-treatment Cornell product was associated with a 14.5% decrease in the composite endpoint (HR. 0.86, 95% CI [0.82-0.90]). In a parallel analysis, 1 SD lower in-treatment Sokolow-Lyon voltage was associated with a 16.6% decrease in the composite endpoint (HR. 0.83, 95% CI [0.78-0.88]). The LIFE study shows that evaluation of both baseline and in-study ECG LVH defined by Cornell product criteria, Sokolow-Lyon voltage criteria or ECG strain improves prediction of CV events and that regression of ECG LVH during antihypertensive treatment is associated with better outcome, independent of blood pressure reduction. |
11,635 | Wolff-Parkinson-White syndrome in the era of catheter ablation: insights from a registry study of 2169 patients. | The management of Wolff-Parkinson-White is based on the distinction between asymptomatic and symptomatic presentations, but evidence is limited in the asymptomatic population.</AbstractText>The Wolff-Parkinson-White registry was an 8-year prospective study of either symptomatic or asymptomatic Wolff-Parkinson-White patients referred to our Arrhythmology Department for evaluation or ablation. Inclusion criteria were a baseline electrophysiological testing with or without radiofrequency catheter ablation (RFA). Primary end points were the percentage of patients who experienced ventricular fibrillation (VF) or potentially malignant arrhythmias and risk factors. Among 2169 enrolled patients, 1001 (550 asymptomatic) did not undergo RFA (no-RFA group) and 1168 (206 asymptomatic) underwent ablation (RFA group). There were no differences in clinical and electrophysiological characteristics between the 2 groups except for symptoms. In the no-RFA group, VF occurred in 1.5% of patients, virtually exclusively (13 of 15) in children (median age, 11 years), and was associated with a short accessory pathway antegrade refractory period (P<0.001) and atrioventricular reentrant tachycardia initiating atrial fibrillation (P<0.001) but not symptoms. In the RFA group, ablation was successful in 98.5%, and after RFA, no patients developed malignant arrhythmias or VF over the 8-year follow-up. Untreated patients were more likely to experience malignant arrhythmias and VF (log-rank P<0.001). Time-dependent receiver-operating characteristic curves for predicting VF identified an optimal anterograde effective refractory period of the accessory pathway cutoff of 240 milliseconds.</AbstractText>The prognosis of the Wolff-Parkinson-White syndrome essentially depends on intrinsic electrophysiological properties of AP rather than on symptoms. RFA performed during the same procedure after electrophysiological testing is of benefit in improving the long-term outcomes.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,636 | SCN5A mutations and polymorphisms in patients with ventricular fibrillation during acute myocardial infarction. | Mutations in the SCN5A gene encoding the Nav1.5 channel α-subunit are known to be risk factors of arrhythmia, including Brugada Syndrome and Long QT syndrome subtype 3. The present study focused on the role of SCN5A variants in the development of ventricular fibrillation (VF) during acute myocardial infarction (AMI). Since VF during AMI is the major cause of sudden death in the Western world, SCN5A mutations represent genetic risk factors for sudden death. By exon re-sequencing, the entire coding region and flanking intron regions were sequenced in 46 AMI/VF+ patients. In total, nine single nucleotide variants were identified of which four represented common single nucleotide polymorphisms (SNPs; 87G>A, 1673A>G, IVS16‑6C>T and 5457T>A). Only five rare variants were identified, each in only one patient. Only two of the rare variants represented missense mutations (3578G>A and 4786T>A). The common SNPs and the missense mutations were also genotyped using polymerase chain reaction methods in 79 AMI/VF‑ patients and 480 healthy controls. The SNPs did not demonstrate significant differences in allele and genotype frequencies between the study groups. The 3578G>A mutation was identified in one out of the 480 controls, whereas the 4786T>A mutation was not present in AMI/VF- patients and controls. In conclusion, the majority of AMI/VF+ patients demonstrated a wild type sequence or common SNPs in SCN5A. Only two out of 46 (4.3%) AMI/VF+ patients revealed mutations that may be involved in Nav1.5 dysfunction and VF. However, this requires further functional validation. |
11,637 | Complications in the clinical course of tako-tsubo cardiomyopathy. | This study evaluated the frequency, severity and outcome of complications in the clinical course of tako-tsubo cardiomyopathy (TTC).</AbstractText>TTC is regarded as a benign disease since left ventricular (LV) function returns to normal within a short time. However, severe complications have been reported in selected patients.</AbstractText>From 37 hospitals, 209 patients (189 female, age 69 ± 12 years) were prospectively included in a TTC registry.</AbstractText>Complications developed in 108/209 patients (52%); 23 (11%) had >2 complications. Complications occurred median 1 day after symptom onset, and 77% were seen within 3 days. Arrhythmias were documented in 45/209 patients (22%) including atrial fibrillation in 32 (15%) and ventricular tachycardia in 17 (8%). Of 8 patients resuscitated (4%), 6 survived. Additional complications were right ventricular involvement (24%), pulmonary edema (13%), cardiogenic shock (7%), transient intraventricular pressure gradients (5%), LV thrombi (3%) and stroke (1%). During hospitalization, 5/209 patients (2.5%) died. Patients with complications were older (70 ± 13 vs 67 ± 10 years, p=0.012), had a higher heart rate (91 ± 26 vs 83 ± 19/min, p=0.025), more frequently Q\ waves on the admission ECG (36% vs 21%, p=0.019) and a lower LV ejection fraction (47 ± 15 vs 54 ± 14%, p = 0.002). Multivariate regression analysis identified Q-waves on admission (OR 2.49, 95% CI 1.23-5.05, p=0.021) and ejection fraction ≤ 30% (OR 4.03, 95% CI 1.04-15.67, p=0.022) as independent predictors for complications.</AbstractText>TTC may be associated with severe complications in half of the patients. Since the majority of complications occur up to day 3, monitoring is advisable for this time period.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,638 | Impact of adverse left ventricular remodeling on sudden cardiac death in patients with hypertrophic cardiomyopathy. | Adverse left ventricular (LV) remodeling predicts heart failure symptoms and overt LV dysfunction in patients with hypertrophic cardiomyopathy (HCM), but its influence on the occurrence of sudden cardiac death (SCD) is unknown. The aim of this study was to investigate the effect of adverse LV remodeling on SCD risk in patients with HCM.</AbstractText>Adverse LV remodeling increases SCD in HCM patients.</AbstractText>This study included 41 patients with HCM who experienced SCD; each case was matched with 3 controls based on age, gender, and time of first contact. In this population of 164 patients, predictors of SCD were identified using univariable and multivariable logistic regression and expressed as odds ratio (OR) with 95% confidence interval (CI).</AbstractText>Baseline characteristics, such as New York Heart Association (NYHA) class, systolic and diastolic left ventricular function, left ventricular wall thickness, left atrial size, atrial fibrillation, and established risk factors for SCD were similar in cases and controls. Independent predictors of SCD during follow-up (median follow-up, 7.7 ± 6.5 years) were: increase in NYHA class (OR: 8.7 [95% CI: 2.5-30.5], P = 0.001), decrease of fractional shortening (per % decrease, OR: 1.09 [95% CI: 1.03-1.14], P = 0.001), and decrease of diastolic function (OR: 3.5 [95% CI: 1.2-10.2], P = 0.02).</AbstractText>This study shows that SCD risk in HCM increases when adverse remodeling occurs. Because cases and controls were similar at baseline, these findings emphasize the importance of vigilant follow-up of HCM patients and could aid clinical decision making concerning implantable cardioverter-defibrillator implantation, especially in patients with moderate risk for SCD.</AbstractText>© 2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,639 | Distinct properties and metabolic mechanisms of postresuscitation myocardial injuries in ventricular fibrillation cardiac arrest versus asphyxiation cardiac arrest in a porcine model. | The two most prevalent causes of sudden cardiac death are ventricular fibrillation cardiac arrest (VFCA) and asphyxiation cardiac arrest (ACA). Profound postresuscitation myocardial dysfunction has been demonstrated in both VFCA and ACA animal models. Our study aimed to characterize the two porcine models of cardiac arrest and postresuscitation myocardial metabolism dysfunction.</AbstractText>Thirty-two pigs were randomized into two groups. The VFCA group (n = 16) were subject to programmed electrical stimulation and the ACA group (n = 16) underwent endotracheal tube clamping to induce cardiac arrest (CA). Once induced, CA remained untreated for a period of 8 minutes. Two minutes following initiation of cardiopulmonary resuscitation (CPR), defibrillation was attempted until return of spontaneous circulation (ROSC) was achieved or animals died. To assess myocardial metabolism, (18)F-FluoroDeoxyGlucose Positron Emission Tomography was performed at baseline and 4 hours after ROSC.</AbstractText>ROSC was 100% successful in VFCA and 50% successful in ACA. VFCA had better mean arterial pressure and cardiac output after ROSC than ACA. Arterial blood gas analysis indicated more detrimental metabolic disturbances in ACA compared with VFCA after ROSC (ROSC 0.5 hours, pH: 7.01 ± 0.06 vs. 7.21 ± 0.03, P < 0.01; HCO3(-): (15.83 ± 2.31 vs. 20.11 ± 1.83) mmol/L, P < 0.01; lactate: (16.22 ± 1.76 vs. 5.84 ± 1.44) mmol/L, P < 0.01). Myocardial metabolism imaging using Positron Emission Tomography demonstrated that myocardial injuries after ACA were more severe and widespread than after VFCA at 4 hours after ROSC (the maximum standardized uptake value of the whole left ventricular: 1.00 ± 0.17 vs. 1.93 ± 0.27, P < 0.01). Lower contents of myocardial energy metabolism enzymes (Na(+)-K(+)-ATPase enzyme activity, Ca(2+)- ATPase enzyme activity, superoxide dismutase and phosphodiesterase) were found in ACA relative to VFCA.</AbstractText>Compared with VFCA, ACA causes more severe myocardium injury and metabolism hindrance, therefore they should be treated as different pathological entities.</AbstractText> |
11,640 | [Association between thyroid dysfunction and incidence of atrial fibrillation in patients with stable angina pectoris]. | To explore the correlation between incidence of atrial fibrillation (AF) and thyroid dysfunction.</AbstractText>Patients with stable angina pectoris with thyroid function test results hospitalized at Fuwai Hospital from 2011 Jan to 2011 Dec were included in this analysis (n = 2 541). General clinical data and related biochemical parameters were analyzed. We divided patients into 5 subgroups according to TSH levels: <0.55 mIU/L (n = 105), 0.55-2.49 mIU/L (n = 1599), 2.50-4.77 mIU/L (n = 621), 4.78-9.99 mIU/L (n = 180), >10.00 mIU/L (n = 36).</AbstractText>A total of 157 patients were diagnosed with AF (6.8%). (1) Compare to stable angina pectoris patients without AF, stable angina pectoris patients with AF have older age (P < 0.001), higher proportion of female (P = 0.04), uric acid (P < 0.001), NT-proBNP (P = 0.001), larger left atrial diameter (P < 0.001), left ventricular end diastolic diameter (P < 0.001) and lower LVEF (P = 0.038), FT3(P = 0.002), TT3 (P < 0.001). (2) When TSH levels were less than 0.55,0.55-2.49, 2.50-4.77, 4.78-9.99 mIU/L and greater than 10.00 mIU/L, the incidence of AF were 7.6% (8/105) , 5.7% (91/1 599), 7.9% (49/621), 9.4% (17/180) and 22.2% (8/36), respectively. Both a high and a low TSH level were associated with an increased incidence of AF. After adjustment for common risk factor (age, gender and so on) , stepwise multiple logistic regression analysis revealed that TSH levels were significantly related with the incidence of AF. Compared to patients with TSH 0.55-2.49 mIU/L, the adjusted odds ratio of AF for TSH < 0.55, 2.50-4.77, 4.78-9.99, >10.00 mIU/L were 1.37 (95%CI 0.65-2.90, P = 0.415), 1.42 (95CI 0.99-2.04, P = 0.057), 1.73 (95%CI 1.01-2.97, P = 0.048), 4.74 (95%CI 2.10-10.69, P < 0.001), respectively.</AbstractText>Our results show that incidence of AF increases in proportion to TSH level in patients with stable angina pectoris.</AbstractText> |
11,641 | Study of spatial relationship of phrenic nerves with cardiac structures relevant to electrophysiologic interventions. | Pulmonary vein (PV) isolation with catheter ablation in treating atrial fibrillation carries the risk of injury to phrenic nerve (PN). Left PN (LPN) stimulation continues to be one of the common complications of transvenous left ventricular lead placement during cardiac resynchronization therapy (CRT).</AbstractText>In 30 formalin-fixed cadavers, spatial relationship of PNs with PV ostia, left atrial appendage (LAA), and cardiac veins was observed. Segmental location of LPN and cardiac vein crossover was also noted. Right and left PNs coursed abutting the ostium of right superior and left superior PVs in five (16.6%) and one (3.33%) cases, respectively. LPN coursed along the lateral surface of LAA in 20 (66.66%) cases and behind LAA in one (3.33%) case. Out of 18 (60%) cases having two cardiac veins draining free wall of left ventricle (LV) and suitable for CRT lead placement, both cardiac veins were crossed by LPN in two (6.66%) cases. LPN-cardiac vein crossover was located in midlateral segment in 10 (33.3%) cases; mid posterolateral segment in five (16.7%) cases; apical lateral segment and apical posterolateral segment in three (10.0%) cases each.</AbstractText>PN is highly susceptible to either injury during catheter ablation or stimulation with LV pacing in certain critical locations. Detailed knowledge of spatial relationship of PNs with cardiac structures could help minimize inadvertent complications during these transcatheter electrophysiological procedures.</AbstractText>©2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,642 | Arrhythmia risk assessment using heart rate variability parameters in patients with frequent ventricular ectopic beats without structural heart disease. | Ventricular ectopic beats (VEBs) are usually considered a benign condition that can be managed with conservative measures. Heart rate variability (HRV), which is one of the most important methods for assessing autonomic activity, is a noninvasive, quantitative method of analyzing autonomic effects on the heart. We aimed to investigate the risk of arrhythmia in patients with VEBs and without cardiovascular disease by using HRV parameters.</AbstractText>Patients with frequent VEBs (more than 30 times in 1 hour, according to the Lown classification) were identified. Identified patients were evaluated by 24-hour ECG recording. Our study included 43 patients with frequent VEBs and 43 controls.</AbstractText>General characteristics of the study population were similar. The LF (low frequency)/HF (high frequency) ratio was significantly higher in the frequent VEBs group than in the control group (P < 0.001). The rate of paroxysmal atrial fibrillation (PAF) was higher in the frequent VEB group than in the control group (P = 0.003). The number of VEBs was correlated with LF/HF ratio and PAF (r = 0.339, P = 0.001 and r = 0.294, P = 0.006, respectively).</AbstractText>Our study showed that the sympathetic nervous system is dominant in young patients with VEBs and without significant comorbidities. There is a higher risk of atrial fibrillation in patients with VEBs and they should be monitored closely for atrial fibrillation.</AbstractText>©2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,643 | Incident atrial fibrillation in systemic sclerosis: the predictive role of B-type natriuretic peptide. | Atrial fibrillation (AF) is common in patients with systemic sclerosis (SSc) and is associated with significant morbidity, mortality, and healthcare expenditures. The aim of this study was to prospectively determine the incidence and the independent predictors of AF in this patient population.</AbstractText>Forty-nine patients (age 50.15 ± 9.25 years, 87.8% female) and 21 healthy controls, all in sinus rhythm, were studied. Evaluation included blood sampling, B-type natriuretic peptide (BNP) measurement, comprehensive electrocardiography and echocardiography at baseline, and 24h ambulatory Holter monitoring at baseline and every 6 months.</AbstractText>During a mean follow-up of 72 ± 24 months, 18 SSc patients (36.7%) developed AF (SSc-AF group) while 31 remained in sinus rhythm (SSc-SR group); all subjects in the control group (Cl group) remained in SR. Baseline differences between SSc-AF, SSc-SR, and Cl groups included: a) left ventricular (LV) mass: 84.5 ± 26 vs. 71.8 ± 18.6 vs. 60.5 ± 32.6 g/m(2), respectively (p=0.017); b) mitral tissue Doppler imaging E velocity: 14.5 ± 2.8 vs. 17.5 ± 3.4 vs. 20.5 ± 4.4 cm/s (p<0.001); c) left atrial (LA) volume: 18.8 ± 7.8 vs. 13.5 ± 5.1 vs. 9.7 ± 5.4 cm(3)/m(2) (p<0.001); d) LA active emptying volume: 7.6 ± 2.7 vs. 4.7 ± 3.2 vs. 3.3 ± 2.2 cm(3)/m(2) (p<0.001); and e) logBNP: 1.78 ± 0.47 vs. 1.31 ± 0.54 vs. 0.66 ± 0.38 pg/mL (p<0.001). In Cox proportional hazard analysis, BNP was the only independent predictor of incident AF.</AbstractText>Incident AF was high in SSc, especially in the presence of LV diastolic dysfunction with LA mechanical overload and elevated BNP levels. BNP was the only independent predictor of incident AF; therefore, it should be considered for risk stratification in this population.</AbstractText> |
11,644 | Nonfluoroscopic catheter visualization in atrial fibrillation ablation: experience from 375 consecutive procedures. | A technological platform (MediGuide) has been recently introduced for nonfluoroscopic catheter tracking. No data on the safety of this technology are yet available in a large cohort of patients.</AbstractText>Data from a prospective ablation registry were analyzed. All patients undergoing atrial fibrillation ablation procedures supported by nonfluoroscopic catheter visualization technology were included. Patient characteristics and procedural data and complications within the first 3 months were recorded. Between May 2012 and February 2014, a total of 375 patients underwent atrial fibrillation ablation using nonfluoroscopic catheter visualization technology. The patients were predominantly men (68%); the majority were ablated for the first time (71%); left atrium was 43±6 mm; and left ventricular function was normal (59±9%). The median ablation procedure time was 135 (113-170) minutes, median fluoroscopy time 2.8 (1.5-4.4) minutes, and median radiation dose 789 (470-1466) cGy*cm(2). Regression analysis demonstrated a significant decrease of fluoroscopy time, dose, and procedure time. To confirm the result and show overall changes, the initial 50 cases (group 1) to the last 50 cases (group 2) of the series were compared: fluoroscopy time decreased from 6.0 (4.1-10.3) minutes in group 1 to 1.1 (0.7-1.5) minutes in group 2 and radiation dose from 2363 (1413-3475) to 490 (230-654) cGy*cm(2), respectively. Ten patients (2.7%) experienced complications: 5 cardiac tamponades (1.4%), 4 pseudoaneurysms (1.1%), and 1 stroke (0.3%).</AbstractText>Atrial fibrillation ablation using the nonfluoroscopic catheter visualization technology is safe with a rate of complications of 2.7%. Procedure time (135 minutes) is not prolonged. A dramatic reduction in fluoroscopy time and dose was achieved.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,645 | New insights on Carpentier I mitral regurgitation from multidetector row computed tomography. | The underlying mechanism of mitral regurgitation (MR) because of isolated annulus dilation (Carpentier type I) remains controversial in patients with atrial fibrillation (AF). The present study evaluated changes in mitral valve geometry of patients with AF and structurally and functionally normal left ventricles and mitral leaflets. Grade of MR and left ventricular (LV) function was evaluated with echocardiography. Changes in mitral valve geometry were evaluated with multidetector row computed tomography (MDCT) performed before radiofrequency catheter ablation for AF. From a cohort of 480 patients with drug-refractory AF referred for catheter ablation, 170 patients (mean age 58 ± 10 years, 67% men) with structural and functional normal left ventricles and mitral leaflets were included. The intercommissural and anteroposterior diameter, perimeter, and area of the mitral annulus and left atrial volume were assessed with MDCT and correlated with the grade of MR as assessed with echocardiography. A total of 49 patients (29%) had MR ≥2+. These patients had larger mitral annulus area compared with patients with MR <2+ (665.0 ± 100.6 mm(2)/m(2) vs 530.5 ± 66.6 mm(2)/m(2), p <0.001), whereas LV size and function (ejection fraction 64.9 ± 6.3% vs 63.1 ± 5.7%, p = 0.08) were similar. After adjusting for age, type of AF, hypertension, left atrial volume, and LV end-systolic volume and ejection fraction, the mitral annulus dimensions remained independently correlated with MR ≥2+. In conclusion, in AF patients with structural and functional normal left ventricles and mitral leaflets, MDCT demonstrated that mitral annulus dilation is independently associated with type I MR. |
11,646 | Altered RyR2 regulation by the calmodulin F90L mutation associated with idiopathic ventricular fibrillation and early sudden cardiac death. | Calmodulin (CaM) association with the cardiac muscle ryanodine receptor (RyR2) regulates excitation-contraction coupling. Defective CaM-RyR2 interaction is associated with heart failure. A novel CaM mutation (CaM(F90L)) was recently identified in a family with idiopathic ventricular fibrillation (IVF) and early onset sudden cardiac death. We report the first biochemical characterization of CaM(F90L). F90L confers a deleterious effect on protein stability. Ca(2+)-binding studies reveal reduced Ca(2+)-binding affinity and a loss of co-operativity. Moreover, CaM(F90L) displays reduced RyR2 interaction and defective modulation of [(3)H]ryanodine binding. Hence, dysregulation of RyR2-mediated Ca(2+) release via aberrant CaM(F90L)-RyR2 interaction is a potential mechanism that underlies familial IVF. |
11,647 | His bundle activates faster than ventricular myocardium during prolonged ventricular fibrillation. | The Purkinje fiber system has recently been implicated as an important driver of the rapid activation rate during long duration ventricular fibrillation (VF>2 minutes). The goal of this study is to determine whether this activity propagates to or occurs in the proximal specialized conduction system during VF as well.</AbstractText>An 8×8 array with 300 µm spaced electrodes was placed over the His bundles of isolated, perfused rabbit hearts (n = 12). Ventricular myocardial (VM) and His activations were differentiated by calculating Laplacian recordings from unipolar signals. Activation rates of the VM and His bundle were compared and the His bundle conduction velocity was measured during perfused VF followed by 8 minutes of unperfused VF. During perfused VF the average VM activation rate of 11.04 activations/sec was significantly higher than the His bundle activation rate of 6.88 activations/sec (p<0.05). However from 3-8 minutes of unperfused VF the His system activation rate (6.16, 5.53, 5.14, 5.22, 6.00, and 4.62 activations/sec significantly faster than the rate of the VM (4.67, 3.63, 2.94, 2.24, 3.45, and 2.31 activations/sec) (p<0.05). The conduction velocity of the His system immediately decreased to 94% of the sinus rate during perfused VF then gradually decreased to 67% of sinus rhythm conduction at 8 minutes of unperfused VF.</AbstractText>During prolonged VF the activation rate of the His bundle is faster than that of the VM. This suggests that the proximal conduction system, like the distal Purkinje system, may be an important driver during long duration VF and may be a target for interventional therapy.</AbstractText> |
11,648 | Left atrial functional reservoir: predictive value for outcome of catheter ablation in paroxysmal atrial fibrillation. | Left arial (LA) function, defined according to conduit, reservoir and booster functions, is closely linked to left ventricular (LV) mechanics, particularly during diastole. Right ventricular pacing (RVP) is thought to impair LA diastolic restoring forces through alteration of ventricular activation. The aim of this study was to determine whether the LA functional reservoir estimated as the change in mean LA ejection fraction (EF) immediately after RVP, and for the second and for the third beats after RVP, predicts clinical outcome in patients with paroxysmal atrial fibrillation (AF) who have undergone catheter ablation (CA). Data from 155 patients with paroxysmal AF (56.0 ± 10.6 years, M:F = 114:41) were analyzed. All patients underwent LA angiography during RVP. LA EFs were measured at the immediate first (LA EF(1)), second (LA EF(2)) and third beats (LA EF(3)) after RVP, using a right anterior oblique 30° view. During follow-up, AF recurred in 35 patients (22.6 %). Mean LA EF(1) was 37.9 ± .8 % in the AF recurrence group and 48.0 ± 8.6 % in the non-recurrence group (P < 0.001). Mean LA EF(2) and LA EF(3) were also lower in the AF recurrence group than in the non-recurrence group (P < 0.001, respectively). Mean percent changes from LA EF(2) to LA EF(3) were -0.4 ± 3.4 in the AF recurrence group and 5.2 ± 4.9 in the non-recurrence group (P = 0.041). The change in mean EF from LA EF(1) to LA EF(3) in the non-recurrence group was significantly greater than in the recurrence group (P = 0.001). Cox regression analysis showed that predictors of AF recurrence were LA EF(2), LA EF(3) and accompanied obstructive sleep apnea (OSA) (P < 0.001, respectively). Decreased functional LA reservoir (LA EF after RVP) and OSA are significantly related to recurrence of AF following CA in patients with paroxysmal AF. |
11,649 | Comparison of intracardiac echocardiography and transesophageal echocardiography for imaging of the right and left atrial appendages. | Transesophageal echocardiography (TEE) is the standard for diagnosis of atrial thrombi and is performed before ablation of atrial arrhythmias. Intracardiac echocardiography (ICE) is routinely used during these procedures and may provide an alternative imaging modality.</AbstractText>The purpose of this study was to compare TEE and ICE for right atrial appendage (RAA) and left atrial appendage (LAA) anatomy and thrombus.</AbstractText>This prospective blinded study enrolled 71 patients with atrial arrhythmias who presented for ablation. TEE and ICE were performed simultaneously to assess the RAA and LAA for thrombi, spontaneous echo contrast, and dimensions. ICE images were acquired sequentially from the right atrium, right ventricular outflow tract, and the pulmonary artery.</AbstractText>Imaging of the RAA and LAA was achieved in all 71 patients using ICE but in only in 69 patients using TEE because of inability to intubate the esophagus. A total of 4 thrombi were diagnosed (3 LAA, 1 RAA). All were detected by ICE but only 1 by TEE. Diagnostic imaging of the LAA was achieved in 71 patients (100%) with ICE and in 62 patients (87.3%) with TEE (P < .002). Spontaneous echo contrast was more commonly diagnosed with ICE (P < .01). There was strong correlation between TEE and ICE for length (r = 0.71), width (r = 0.94), and area (r = 0.88) of the LAA. Image quality with ICE was highest from the pulmonary artery and lowest from the right atrium.</AbstractText>ICE imaging is a viable alternative to TEE for visualization of the LAA and RAA during catheter ablation procedures.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,650 | Use of esmolol after failure of standard cardiopulmonary resuscitation to treat patients with refractory ventricular fibrillation. | We compare the outcomes for patients who received esmolol to those who did not receive esmolol during refractory ventricular fibrillation (RVF) in the emergency department (ED).</AbstractText>A retrospective investigation in an urban academic ED of patients between January 2011 and January 2014 of patients with out-of-hospital or ED cardiac arrest (CA) with an initial rhythm of ventricular fibrillation (VF) or ventricular tachycardia (VT) who received at least three defibrillation attempts, 300mg of amiodarone, and 3mg of adrenaline, and who remained in CA upon ED arrival. Patients who received esmolol during CA were compared to those who did not.</AbstractText>90 patients had CA with an initial rhythm of VF or VT; 65 patients were excluded, leaving 25 for analysis. Six patients received esmolol during cardiac arrest, and nineteen did not. All patients had ventricular dysrhythmias refractory to many defibrillation attempts, including defibrillation after administration of standard ACLS medications. Most received high doses of adrenaline, amiodarone, and sodium bicarbonate. Comparing the patients that received esmolol to those that did not: 67% and 42% had temporary return of spontaneous circulation (ROSC); 67% and 32% had sustained ROSC; 66% and 32% survived to intensive care unit admission; 50% and 16% survived to hospital discharge; and 50% and 11% survived to discharge with a favorable neurologic outcome, respectively.</AbstractText>Beta-blockade should be considered in patients with RVF in the ED prior to cessation of resuscitative efforts.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,651 | Left atrial function in heart failure with impaired and preserved ejection fraction. | Left atrial structural and functional changes in heart failure are relatively ignored parts of cardiac assessment. This review illustrates the pathophysiological and functional changes in left atrium in heart failure as well as their prognostic value.</AbstractText>Heart failure can be divided into those with systolic dysfunction and heart failure with preserved ejection fraction (HFPEF). Left atrial enlargement and dysfunction commonly occur in systolic heart failure, in particular, in idiopathic dilated cardiomyopathy. Atrial enlargement and dysfunction also carry important prognostic value in systolic heart failure, independently of known parameters such as left ventricular ejection fraction. In HFPEF, there is evidence of left atrial enlargement, impaired atrial compliance, and reduction of atrial pump function. This occurs not only at rest but also during exercise, indicating significant impairment of atrial contractile reserve. Furthermore, atrial dyssynchrony is common in HFPEF. These factors further contribute to the development of new onset or progression of atrial arrhythmias, in particular, atrial fibrillation.</AbstractText>Left atrial function is an integral part of cardiac function and its structural and functional changes in heart failure are common. As changes of left atrial structure and function have different clinical implications in systolic heart failure and HFPEF, routine assessment is warranted.</AbstractText> |
11,652 | Clinical profile, management, and outcome in patients with out of hospital cardiac arrest: insights from a 20-year registry. | There is limited information regarding the clinical characteristics and outcome of out of hospital cardiac arrest (OHCA) in Middle Eastern patients. The aim of this study was to evaluate clinical characteristics, treatment, and outcomes in patients admitted following OHCA at a single center in the Middle East over a 20-year period.</AbstractText>The data used for this hospital-based study were collected for patients hospitalized with OHCA in Doha, Qatar, between 1991 and 2010. Baseline clinical characteristics, in-hospital treatment, and outcomes were studied in comparison with the rest of the admissions.</AbstractText>A total of 41,453 consecutive patients were admitted during the study period, of whom 987 (2.4%) had a diagnosis of OHCA. Their average age was 57±15 years, and 72.7% were males, 56.5% were Arabs, and 30.9% were South Asians. When compared with the rest of the admissions taken as a reference, patients with OHCA were more likely to have diabetes mellitus (42.8% versus 39.1%, respectively, P=0.02), prior myocardial infarction (21.8% versus 19.2%, P=0.04), and chronic renal failure (7.4% versus 3.9%, P=0.001), but were less likely to have dyslipidemia (16.9% versus 25.4%, P=0.001). Further, 52.6% of patients had preceding symptoms, the most common of which was chest pain (27.2%) followed by dyspnea (24.8%). An initially shockable rhythm (ventricular fibrillation or ventricular tachycardia) was present in 25.1% of OHCA patients, with ST segment elevation myocardial infarction documented in 30.0%. Severely reduced left ventricular systolic function (ejection fraction ≤35%) was present in 53.2% of OHCA patients; 42.9% had cardiogenic shock requiring use of inotropes at presentation. An intra-aortic balloon pump was inserted in 3.6% of cases. Antiarrhythmic medications were used in 27.4% and thrombolytic therapy in 13.9%, and 10.8% underwent a percutaneous coronary procedure (coronary angiography ± percutaneous coronary intervention). The in-hospital mortality rate was 59.8%.</AbstractText>OHCA was associated with higher incidences of diabetes, prior myocardial infarction, and chronic kidney disease as compared with the remaining admissions. Approximately half of the patients had no preceding symptoms. In-hospital mortality was high (59.8%), but similar to the internationally published data.</AbstractText> |
11,653 | Failed anti-tachycardia pacing can be used to differentiate atrial arrhythmias from ventricular tachycardia in implantable cardioverter-defibrillators. | Atrial fibrillation/tachycardia (AF/AT) may result in inappropriate therapies in implantable cardioverter-defibrillators (ICDs). The post-pacing interval (PPI) and tachycardia cycle length difference (PPI - TCL) has been previously demonstrated to indicate the proximity of the pacing site to a tachycardia origin.</AbstractText>We postulated that the PPI and PPI - TCL would be greater in AT/AF vs. ventricular tachycardia (VT) after episodes of failed anti-tachycardia pacing (ATP).</AbstractText>This was a single-centre, retrospective study evaluating consecutive patients implanted with dual (DR)/biventricular (BIV) ICDs. Stored electrograms were used to determine whether the ATP captured the arrhythmia and the arrhythmia did not present with primary or secondary termination. Measurements were done using manual calipers. A total of 155 patients were included. There were 79 BIV and 76 DR devices. In total, 39 episodes were identified in 20 patients over a 23-month follow-up period. A total of 76 sequences of ATP (burst/ramp) were delivered, 28 (37%) of them inappropriate. Fifty-one events (18 AT/AF and 33 VT) were compared. The mean PPI was 693 ± 96 vs. 512 ± 88 ms (P < 0.01) and the mean PPI - TCL was 330 ± 97 vs. 179 ± 103 ms (P < 0.01) for AT/AF and VT, respectively. Cut-offs of 615 ms for the PPI [area under curve (AUC) 0.93; 95% confidence interval (CI): 0.84-1.00; P < 0.01] and 260 ms for PPI - TCL (AUC 0.86; 95% CI: 0.74-0.98; P < 0.01) were identified.</AbstractText>The PPI and PPI - TCL after failed ATP differs significantly between AF/AT and VT and are therefore useful indices to discriminate between supraventricular tachycardia and VT in ICDs.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
11,654 | Predictors of hospitalization for heart failure and of all-cause mortality after atrioventricular nodal ablation and right ventricular pacing for atrial fibrillation. | Atrioventricular junction ablation (AVJA) is a highly effective treatment in patients with therapy refractory atrial fibrillation (AF) but renders the patient pacemaker dependent. We aimed to analyse the long-term incidence of hospitalization for heart failure (HF) and all-cause mortality in patients who underwent AVJA because of AF and to determine predictors for HF and mortality.</AbstractText>We retrospectively enrolled 162 consecutive patients, mean age 67 ± 9 years, 48% women, who underwent AVJA because of symptomatic AF refractory to pharmacological treatment (n = 117) or unsuccessful repeated pulmonary vein isolation (n = 45). Hospitalization for HF occurred in 32 (20%) patients and 35 (22%) patients died, representing a cumulative incidence for hospitalization for HF and mortality over the first 2 years after AVJA of 9.1 and 5.2%, respectively. Hospitalization for HF occurred to the same extent in patients who failed pharmacological treatment as in patients with repeated pulmonary vein isolation (PVI), although the mortality was slightly higher in the former group. QRS prolongation ≥120 ms and left atrial diameter were independent predictors of hospitalization for HF, while hypertension and previous HF were independent predictors of death.</AbstractText>The long-term hospitalization rate for HF and all-cause mortality was low, which implies that long-term ventricular pacing was not harmful in this patient population, including patients with unsuccessful repeated PVI.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
11,655 | Caspase-3-mediated splenic lymphocyte apoptosis in a porcine model of cardiac arrest. | Postresuscitation immunologic dysfunction contributes to the low survival rate after successful resuscitation, but its mechanism remains poorly understood. The mitochondrial apoptosis pathway is initiated by the Bcl-2/Bax-controlled and caspase-3-mediated pathway, this study investigated whether mitochondrial pathway-mediated splenic lymphocyte apoptosis is involved in the postresuscitation immunosuppression in a porcine model of cardiac arrest.</AbstractText>Twenty-eight Wuzhishan miniature pigs were randomly divided into 2 groups: return of spontaneous circulation (ROSC; n = 22) and sham-operated (n = 6). Return of spontaneous circulation was initiated after 8 minutes of untreated ventricular fibrillation. After successful ROSC, CD4(+) and CD8(+) lymphocyte subsets were determined by flow cytometry. Surviving pigs were randomly assigned to be humanely killed at 24 and 72 hours after ROSC (n = 8 per group). Spleens were removed for histopathologic analysis, Western blotting, quantitative real-time polymerase chain reaction, and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay.</AbstractText>A high degree of splenic lymphocyte apoptosis was observed in the ROSC group. Expression of Bax and activated caspase-3 was markedly increased in splenic tissue, whereas Bcl-2 was significantly decreased in the post-ROSC group compared with the sham-operated group (P < .05) at 24 and 72 hours after ROSC. The messenger RNA levels of activated caspase-3 of splenic tissue were significantly elevated at 24 and 72 hours after ROSC.</AbstractText>These results demonstrates that Bcl-2/Bax and caspase-3-mediated mitochondrial apoptosis signaling pathway may contribute to abnormal splenic lymphocyte apoptosis, which may be one of the main pathologic mechanisms of postresuscitation disturbance of immunologic function in a porcine model of cardiac arrest.</AbstractText>Copyright © 2014 Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,656 | Long-term outcomes after mitral valve repair for degenerative mitral regurgitation with persistent atrial fibrillation. | Atrial fibrillation (AF) adversely affects surgical outcomes of mitral valve surgery. However, the long-term impact of Maze procedure has not been clear yet.</AbstractText>We retrospectively investigated 159 patients who underwent mitral valve repair for degenerative mitral regurgitation with persistent AF between 1991 and 2010. The mean age of patients was 63.1 ± 10.5 years. After we started performing Maze procedure in 2002, 65 patients underwent concomitant Maze procedure. The median follow-up time was 7.5 years.</AbstractText>There was one operative death (0.63%). The overall survival rate was 91.0 ± 2.6% at 5 years and 79.1 ± 4.7% at 10 years. Survival was significantly better in patients who underwent Maze procedure than those who did not. The rate of freedom from AF in patients who underwent Maze procedure was 86.4 ± 4.5% at 1 year and 81.1 ± 5.6% at 5 years. The freedom rate from stroke was higher in patients who underwent Maze procedure than those who did not. Patients with postoperative AF had larger left ventricular systolic and diastolic diameters at follow-up and higher New York Heart Association functional class than patients without postoperative AF (1.4 ± 0.5 vs. 1.1 ± 0.3, p < 0.001).</AbstractText>Maze procedure can have a positive effect on long-term survival, freedom from stroke, and cardiac function.</AbstractText>Georg Thieme Verlag KG Stuttgart · New York.</CopyrightInformation> |
11,657 | Radiofrequency ablation of left atrial flutter mediated with double potentials in a seemingly normally structured heart. | Left atrial flutter (left AFL) is common in patients who undergo atrial fibrillation ablation and cardiac surgery; however, few reports describe left AFL in detail in a seemingly normally structured heart, and the mechanisms of the occurrence of such arrhythmia are still not clear. We describe left AFL in patients without prior cardiac surgery or catheter ablation and discuss the electrophysiological characteristics that may explain the preferential generation and perpetuation of such tachycardia.</AbstractText>Eleven patients with left AFL, who had no history of cardiac surgery or interventions, underwent electrophysiological studies and 3-dimensional electroanatomic mapping studies. Echocardiography revealed a relatively mild dilation of the left atrium, mild to moderate mitral regurgitation, and a normal left ventricular ejection fraction. The electroanatomic mapping during tachycardia showed a "reentrant" activation pattern in all patients. The mean tachycardia cycle length was 266 ± 17 ms. A single-loop reentrant circuit was identified in 7 patients. A counterclockwise left atrial flutter evolved around the mitral valve annulus in 6 patients. The tachycardia rotated around the left atrial anterior wall in 1 patient. Four patients exhibited a double-loop reentrant circuit with a "figure of 8" pattern reentry. Double potentials as the critical isthmus of the circuit were identified in the left atrial anterior wall near the mitral annulus which displayed a low-voltage area matched with the left atrium-aorta contiguity. The conduction velocity was significantly slower in the double-potential recording area than in the lateral mitral annulus (0.36 ± 0.03 m/s vs 0.74 ± 0.12 m/s; P<0.05). Successful ablation around the double-potential recording site caused an interruption of the tachycardia, and remained free of recurrence during a 12-month follow-up in all patients.</AbstractText>Left AFL in patients without a history of surgery or ablation is rarely observed in clinical practice. The successful site of ablation was within the anterior wall near the mitral annulus showing the double potentials as the critical part of the reentrant circuit. This suggests that perhaps a double potential-targeted ablation may be effective for these patients.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,658 | A wavelet transform based feature extraction and classification of cardiac disorder. | This paper approaches an intellectual diagnosis system using hybrid approach of Adaptive Neuro-Fuzzy Inference System (ANFIS) model for classification of Electrocardiogram (ECG) signals. This method is based on using Symlet Wavelet Transform for analyzing the ECG signals and extracting the parameters related to dangerous cardiac arrhythmias. In these particular parameters were used as input of ANFIS classifier, five most important types of ECG signals they are Normal Sinus Rhythm (NSR), Atrial Fibrillation (AF), Pre-Ventricular Contraction (PVC), Ventricular Fibrillation (VF), and Ventricular Flutter (VFLU) Myocardial Ischemia. The inclusion of ANFIS in the complex investigating algorithms yields very interesting recognition and classification capabilities across a broad spectrum of biomedical engineering. The performance of the ANFIS model was evaluated in terms of training performance and classification accuracies. The results give importance to that the proposed ANFIS model illustrates potential advantage in classifying the ECG signals. The classification accuracy of 98.24 % is achieved. |
11,659 | Outcomes of heart failure with preserved ejection fraction in a Southeast Asian cohort. | Heart failure with preserved ejection fraction (HF-PEF) has been shown to be of better or equivalent prognosis than heart failure with reduced ejection fraction (HF-REF). We aimed to characterize and study the outcome of HF-PEF in a multiethnic South East Asian context.</AbstractText>This is a single-centre retrospective analysis of 312 patients admitted with decompensated heart failure over 1 year from January to December 2009. We evaluated clinical characteristics of patients according to left ventricular ejection fraction at least 50 or less than 50%. Outcomes as defined by 1-year mortality and 90-day re-hospitalization rates for heart failure were compared between the two groups in an in-patient setting.</AbstractText>The median age was 68 years and median length of hospitalization was 4 days. Around 21.8% had HF-PEF. Patients with preserved ejection fraction were more often older, female, hypertensive, with atrial fibrillation, had no coronary artery disease and had never smoked before. They were less often prescribed antiplatelets, angiotensin-converting enzyme inhibitor/angiotensin-II receptor blocker, aldosterone-receptor antagonists, digoxin and loop diuretics. After 1 year, mortality was 5.9% in patients with HF-PEF and 11.3% in those with HF-REF, but the difference was nonsignificant (P = 0.195). There was also no difference in 90-day rehospitalization rates between the groups (16.2 vs. 17.6%, respectively, P = 0.780). Poor prognostic factors for the cohort of heart failure patients included increased age, diabetes and renal impairment, but not left ventricular ejection fraction.</AbstractText>HF-PEF is associated with distinct risk factors from HF-REF, but has a similar morbidity and mortality to HF-REF.</AbstractText> |
11,660 | Therapeutic hypothermia in the intensive cardiac care unit. | Therapeutic hypothermia has demonstrated to improve both survival and neurological outcome in patients who experienced an out-of-hospital cardiac arrest. Nevertheless, many aspects of its clinical application are still controversial. Current guidelines recommend to cool patients who survive a cardiac arrest due to either ventricular fibrillation or ventricular tachycardia, whereas the beneficial effect of lowering body temperature in nonshockable rhythms is still questionable due to the lack of randomized controlled trial involving this subgroup of patients. Although therapeutic hypothermia is often begun before hospital arrival, the optimal time to start cooling is still a matter of debate. Furthermore, different methods are available to low body temperature, but no direct comparisons are available to establish which device performs better than others, and a combination of external and endovascular cooling is usually preferred. The present review is aimed at summarizing the available evidence supporting the use in clinical practice of mild hypothermia in comatose survivors from cardiac arrest and at evaluating its adverse events and their treatment. |
11,661 | [Perioperative cardiovascular abnormality in elder patients with silent coronary heart disease]. | To explore the perioperative cardiovascular dysfunction and its relevance to age in patients with silent coronary heart disease (or silent myocardial ischemia), and explore the clinical treatment and recovery of perioperative arrhythmias.</AbstractText>One hundred and eighty cases were selected from selective surgery patients with silent myocardial ischemia (SMI). Among the cases, 130 patients older than 51 years old were divided into 51 - 60 year-old group, 61- 70 year-old group and 71 - 80 year-old group. Control group was set up by other 50 patients younger than 51 years old. Electrocardiogram data of 24 h before the operation, 24 h after the operation and 48 h after the operation were continuously monitored by dynamic electrocardiogram (DCG). The electrocardiogram data of ST shifting, arrhythmia incidences of different type and at different time were analyzed by professional doctors. At the same time, the treatment and recovery of perioperative arrhythmia were recorded.</AbstractText>As the age increase, the magnitude and duration of ST shifting appeared upward trend compared to the control group (P < 0.05, P < 0.01). The incidence of ST elevation in 71 - 80 year-old group was higher than the control group (P < 0.05). The ST depression duration in 61 - 70 and 71 - 80 year-old group and ST elevation magnitude in 71 - 80 year-old group were higher than 51 - 60 year-old group (P < 0.05). Compared to the control group, the incidence of accelerated idioventricular rhythm (AIR) in 61 - 70 year-old group and the incidence of sinus bradycardia (SB), ventricular premature beat (VPB), ventricular tachycardia (VT) in 71 - 80 year-old group were higher (P < 0.05, P < 0.01). Compared to the 51 - 60 year-old group, the incidence of atrial fibrillation (AF) in 61 - 70 year-old group and the incidence of VP, VT, AF in 71 - 80 year-old group were higher (P < 0.05, P < 0.01). The arrhythmia incidences in 24 h after operation were higher than 48 h after operation and 24 h before operation (P < 0.01). As the age increase, the recovery incidence by removing inducement was decreased, but the recovery incidences by drug and electric-shock treatment were increased (P < 0.05).</AbstractText>Old SMI patients have high levels of perioperative myocardial ischemia and arrhythmia, and 24 h after operation is the period of high incidence.</AbstractText> |
11,662 | Prevalence of type 1 Brugada ECG pattern after administration of Class 1C drugs in patients with type 1 myotonic dystrophy: Myotonic dystrophy as a part of the Brugada syndrome. | Both type 1 myotonic dystrophy (MD1) and Brugada syndrome (BrS) may be complicated by conduction disturbances and sudden death. Spontaneous BrS has been observed in MD1 patients, but the prevalence of drug-induced BrS in MD1 is unknown.</AbstractText>The purpose of this study was to prospectively assess the prevalence of type 1 ST elevation as elicited during pharmacologic challenge with Class 1C drugs in a subgroup of MD1 patients and to further establish correlations with ECG and electrophysiologic variables and prognosis.</AbstractText>From a group of unselected 270 MD1 patients, ajmaline or flecainide drug challenge was performed in a subgroup of 44 patients (27 men, median age 43 years) with minor depolarization/repolarization abnormalities suggestive of possible BrS. The presence of type 1 ST elevation after drug challenge was correlated to clinical, ECG, and electrophysiologic variables.</AbstractText>Eight of 44 patients (18%) presented with BrS after drug challenge. BrS was seen more often in men (26% vs 6%, P = .09) and was related to younger age (35 vs 48 years, P = .07). BrS was not correlated to symptoms, baseline ECG, HV interval, results of signal-averaged ECG, or abnormalities on ambulatory recordings. MD1 patients with BrS had longer corrected QT intervals, greater increase in PR interval after drug challenge, and higher rate of inducible ventricular arrhythmias (62% vs 21%, P = .03). Twelve patients were implanted with a pacemaker and 5 with an implantable cardioverter-defibrillator. Significant bradycardia did not occur in any patients, and malignant ventricular arrhythmia never occurred during median 7-year follow-up (except 1 hypokalemia-related ventricular fibrillation).</AbstractText>BrS is elicited by a Class 1 drug in 18% of MD1 patients presenting with minor depolarization/repolarization abnormalities at baseline, but the finding seems to be devoid of a prognostic role.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,663 | Resumption of chest compressions after successful defibrillation and risk for recurrence of ventricular fibrillation in out-of-hospital cardiac arrest. | Prior investigation of out-of-hospital cardiac arrest has raised the concern that ventricular fibrillation (VF) recurrence may be triggered by chest compression (CC) resumption. We investigated predictors of VF recurrence after defibrillation, including timing of CC resumption.</AbstractText>Patients with witnessed out-of-hospital cardiac arrest and initial rhythm of VF from an Utstein-style database were analyzed. For each shock that defibrillated VF, CC resumption and VF recurrence times were determined. Shocks were classified according to postshock rhythm. Factors (age, sex, time from dispatch to monitor/defibrillator application, and CC resumption) that could predict VF recurrence were analyzed. CC resumption was categorized into groups: CC1, 1 to 5 seconds; CC2, 6 to 10 seconds; CC3, 11 to 30 seconds; and CC4, >30 seconds. Eighty-eight subjects were analyzed, with a total of 285 shocks, with 226 shocks that achieved asystole (n=102), organized rhythm (n=120), or monomorphic ventricular tachycardia (n=4). After a successful shock, CC resumption occurred at a median (interquartile range) of 8 (5-18) seconds. VF recurred after 166 shocks (74%) and recurred within 30 seconds in 69 shocks. There was no significant relationship between VF recurrence and factors analyzed including CC resumption time, nor stratified by postshock rhythm. The hazard ratios (HRs) for VF recurrence within 30 seconds for later CC groups (CC2, CC3, and CC4) relative to early CC resumption (CC1) were as follows: HR(CC2)=1.05 (P=0.9); HR(CC3)=1.75 (P=0.1); and HR(CC4)=0.67 (P=0.4).</AbstractText>VF recurrence within 30 seconds of a defibrillatory shock was not dependent on timing of CC resumption in patients with witnessed arrest and initial rhythm of VF.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,664 | A genome-wide association study to identify genomic modulators of rate control therapy in patients with atrial fibrillation. | For many patients with atrial fibrillation, ventricular rate control with atrioventricular (AV) nodal blockers is considered first-line therapy, although response to treatment is highly variable. Using an extreme phenotype of failure of rate control necessitating AV nodal ablation and pacemaker implantation, we conducted a genome-wide association study (GWAS) to identify genomic modulators of rate control therapy. Cases included 95 patients who failed rate control therapy. Controls (n = 190) achieved adequate rate control therapy with ≤2 AV nodal blockers using a conventional clinical definition. Genotyping was performed on the Illumina 610-Quad platform, and results were imputed to the 1000 Genomes reference haplotypes. A total of 554,041 single-nucleotide polymorphisms (SNPs) met criteria for minor allele frequency (>0.01), call rate (>95%), and quality control, and 6,055,224 SNPs were available after imputation. No SNP reached the canonical threshold for significance for GWAS of p <5 × 10(-8). Sixty-three SNPs with p <10(-5) at 6 genomic loci were genotyped in a validation cohort of 130 cases and 157 controls. These included 6q24.3 (near SAMD5/SASH1, p = 9.36 × 10(-8)), 4q12 (IGFBP7, p = 1.75 × 10(-7)), 6q22.33 (C6orf174, p = 4.86 × 10(-7)), 3p21.31 (CDCP1, p = 1.18 × 10(-6)), 12p12.1 (SOX5, p = 1.62 × 10(-6)), and 7p11 (LANCL2, p = 6.51 × 10(-6)). However, none of these were significant in the replication cohort or in a meta-analysis of both cohorts. In conclusion, we identified several potentially important genomic modulators of rate control therapy in atrial fibrillation, particularly SOX5, which was previously associated with heart rate at rest and PR interval. However, these failed to reach genome-wide significance. |
11,665 | Late and very late drug-eluting stent thrombosis in the immediate postoperative period after antiplatelet withdrawal: a retrospective study. | Late (31-360 days after deployment) and very late (>360 days after deployment) stent thrombosis is a feared complication after drug-eluting stent (DES) deployment. The American College of Cardiology/American Heart Association guidelines recommend dual antiplatelet therapy for 12 months due to the lack of protection beyond this period in randomized trials. The perioperative period is a unique state of generalized hypercoagulability which can predispose people to DES thrombosis when combined with the rebound hypercoagulable effect of antiplatelet withdrawal.</AbstractText>A retrospective chart review was performed to detect incidences of late and very late postoperative DES thrombosis after elective noncardiac surgery. Only definite and probable cases of stent thrombosis were included. All cases were analyzed for patient demographics, comorbidities, type of surgery, intervention history, preoperative antiplatelets management, postoperative course and outcome.</AbstractText>A total of six patients with prior DES deployment (10-42 months earlier, average 30 months) developed DES thrombosis (five very late and one late) in the immediate postoperative period. All patients had stable coronary artery disease and were cleared for surgery (intermediate cardiac risk surgery) by their cardiologist. In all patients, antiplatelets were discontinued 4-7 days (average 5.6 days) prior to surgery to minimize operative bleeding. Five of six patients developed ST-segment elevation myocardial infarction. Half of the patients had simultaneous two-vessel DES thrombosis and two cases had single vessel thrombosis. Three patients developed ventricular fibrillation and cardiac arrest. One-third of the patients died during the index hospitalization. Coronary thrombectomy and angioplasty was successful in the remaining four cases. The incidence of postoperative late and very late DES thrombosis among all patients undergoing noncardiac surgery who were older than 40 years was 0.006%.</AbstractText>Caution should be exercised when attempting to withdraw antiplatelets preoperatively in patients with DES even when the recommended 12-month period of dual antiplatelet therapy (DAPT) has elapsed. The significant morbidity and mortality of this complication warrants further research to study the ideal perioperative management of antiplatelets in patients with prior DES deployment over 1 year who are still receiving DAPT.</AbstractText>© The Author(s), 2014.</CopyrightInformation> |
11,666 | Impact of presenting rhythm on short- and long-term neurologic outcome in comatose survivors of cardiac arrest treated with therapeutic hypothermia. | To compare short- and long-term neurologic outcomes in comatose survivors of out-of-hospital cardiac arrest treated with mild therapeutic hypothermia presenting with nonshockable versus shockable initial rhythms.</AbstractText>Retrospective cohort study.</AbstractText>Emergency department and ICU of an academic hospital.</AbstractText>One hundred twenty-three consecutive post-out-of-hospital cardiac arrest adults (57 nonshockable rhythms, 66 shockable rhythms) treated with therapeutic hypothermia between 2006 and 2012.</AbstractText>None.</AbstractText>Data were collected from electronic health records. Neurologic outcomes were dichotomized by Cerebral Performance Category at discharge and 6- to 12-month follow-up and analyzed via multivariable logistic regressions. Groups were similar, except nonshockable rhythm patients were more likely to have a history of diabetes mellitus (p = 0.01), be dialysis dependent (p = 0.01), and not have bystander cardiopulmonary resuscitation (p = 0.05). At discharge, 3 of 57 patients (5%) with nonshockable rhythm versus 28 of 66 (42%) with shockable rhythm had a favorable outcome (unadjusted odds ratio, 0.08; 95% CI, 0.02-0.3; adjusted odds ratio, 0.1; 95% CI, 0.03-0.4). At follow-up, 4 of 55 patients (7%) versus 29 of 60 (48%) with nonshockable rhythm and shockable rhythm, respectively, had a favorable Cerebral Performance Category (odds ratio, 0.08; 95% CI, 0.03-0.3; adjusted odds ratio, 0.09; 95% CI, 0.09-0.3). Among those surviving hospitalization, favorable neurologic outcome was more likely at long-term follow-up than at hospital discharge for both groups (odds ratio, 2.5; 95% CI, 1.3-4.7; adjusted odds ratio, 2.9; 95% CI, 1.4-6.2). No significant interaction between changes in neurologic status over time and presenting rhythm was seen (p = 0.93).</AbstractText>These data indicate an association between initial nonshockable rhythm and significantly worse short- and long-term outcomes in patients treated with mild therapeutic hypothermia. Among survivors, neurologic status significantly improved over time for all patients and shockable rhythm patients and tended to improve over time for the small number of nonshockable rhythm patients who survived beyond hospitalization. No significant interaction between changes in neurologic status over time and presenting rhythm was seen.</AbstractText> |
11,667 | Ventricular arrhythmias in the North American multidisciplinary study of ARVC: predictors, characteristics, and treatment. | Arrhythmogenic right ventricular cardiomyopathy (ARVC) is associated with sudden cardiac death. However, the selection of patients for implanted cardioverter-defibrillators (ICDs), as well as programming of the ICD, is unclear.</AbstractText>The objective of this study was to identify predictors, characteristics, and treatment of ventricular arrhythmias in patients with ARVC.</AbstractText>The Multidisciplinary Study of Right Ventricular Cardiomyopathy established the North American ARVC Registry and enrolled patients with a diagnosis of ARVC. Patients were followed prospectively.</AbstractText>Of 137 patients enrolled, 108 received ICDs. Forty-eight patients had 502 sustained episodes of ventricular arrhythmias, including 489 that were monomorphic and 13 that were polymorphic. In the patients with ICDs, independent predictors of ventricular arrhythmias in follow-up included spontaneous sustained ventricular arrhythmias before ICD implantation and T-wave inversions inferiorly. The only independent predictor for life-threatening arrhythmias, defined as sustained ventricular tachycardia (VT) ≥240 beats/min or ventricular fibrillation, was a younger age at enrollment. Anti-tachycardia pacing (ATP), independent of the cycle length of the VT, was successful in terminating 92% of VT episodes.</AbstractText>In the North American ARVC Registry, the majority of ventricular arrhythmias in follow-up are monomorphic. Risk factors for ventricular arrhythmias were spontaneous ventricular arrhythmias before enrollment and a younger age at ICD implantation. ATP is highly successful in terminating VT, and all ICDs should be programmed for ATP, even for rapid VT.</AbstractText>Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,668 | Average current is better than peak current as therapeutic dosage for biphasic waveforms in a ventricular fibrillation pig model of cardiac arrest. | Defibrillation current has been shown to be a clinically more relevant dosing unit than energy. However, the effects of average and peak current in determining shock outcome are still undetermined. The aim of this study was to investigate the relationship between average current, peak current and defibrillation success when different biphasic waveforms were employed.</AbstractText>Ventricular fibrillation (VF) was electrically induced in 22 domestic male pigs. Animals were then randomized to receive defibrillation using one of two different biphasic waveforms. A grouped up-and-down defibrillation threshold-testing protocol was used to maintain the average success rate of 50% in the neighborhood. In 14 animals (Study A), defibrillations were accomplished with either biphasic truncated exponential (BTE) or rectilinear biphasic waveforms. In eight animals (Study B), shocks were delivered using two BTE waveforms that had identical peak current but different waveform durations.</AbstractText>Both average and peak currents were associated with defibrillation success when BTE and rectilinear waveforms were investigated. However, when pathway impedance was less than 90Ω for the BTE waveform, bivariate correlation coefficient was 0.36 (p=0.001) for the average current, but only 0.21 (p=0.06) for the peak current in Study A. In Study B, a high defibrillation success (67.9% vs. 38.8%, p<0.001) was observed when the waveform delivered more average current (14.9±2.1A vs. 13.5±1.7A, p<0.001) while keeping the peak current unchanged.</AbstractText>In this porcine model of VF, average current was better than peak current to be an adequate parameter to describe the therapeutic dosage when biphasic defibrillation waveforms were used. The institutional protocol number: P0805.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,669 | Impact of intensified postresuscitation treatment on outcome of comatose survivors of out-of-hospital cardiac arrest according to initial rhythm. | We investigated the impact of intensified postresuscitation treatment in comatose survivors of out-of-hospital cardiac arrest (OHCA) of presumed cardiac etiology according to the initial rhythm at the emergency medical team arrival.</AbstractText>Interventions and survival with Cerebral Performance Category (CPC) 1-2 within each group were retrospectively compared between the periods of conservative (1995-2003) and intensified (2004-2012) postresuscitation treatment.</AbstractText>In shockable group, therapeutic hypothermia (TH) increased from 1 to 93%, immediate invasive coronary strategy from 28 to 78%, intraaortic balloon pump from 4 to 21%, vasopressors/inotropes from 47 to 81% and antimicrobial agents from 65 to 86% during the intensified period as compared to conservative period (p<0.001). This was associated with increased survival with CPC 1-2 from 27 to 47% (p<0.001). After adjusting for age, sex and prehospital confounders, TH (OR=2.12, 95% CI 1.25-3.61), percutaneous coronary intervention (OR 1.77, 95% CI 1.15-2.73) and antimicrobial agents (OR=12.21, 95% CI 5.13-29.08) remained associated with survival with CPC 1-2. In non-shockable patients, TH also significantly increased from 1 to 74%, immediate invasive coronary strategy from 8 to 51%, intraaortic balloon pump from 2 to 9% and vasopressors/inotropes from 56 to 84% during intensified period without concomitant increase in survival with CPC 1-2 (7% vs. 9%; p=0.27). After adjustment, only antimicrobial agents (OR=8.43, 95% CI: 1.05-67.72) remained associated with survival with CPC 1-2.</AbstractText>Intensified postresuscitation treatment was associated with doubled survival in comatose survivors of OHCA with shockable rhythm. Such association could not be demonstrated in patients with non-shockable rhythm.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,670 | High-fidelity simulation enhances ACLS training. | Medical student training and experience in cardiac arrest situations is limited. Traditional Advanced Cardiac Life Support (ACLS) teaching methods are largely unrealistic with rare personal experience as team leader. Yet Postgraduate Year 1 residents may perform this role shortly after graduation.</AbstractText>We expanded our ACLS teaching to a "Resuscitation Boot Camp" where we taught 2010 ACLS to 19 pregraduation students in didactic (12 hours) and experiential (8 hours) format.</AbstractText>Immediately before the course, we recorded students performing an acute coronary syndrome/ventricular fibrillation (VF) scenario. As a final test, we recorded the same scenario for each student. Primary outcomes were time to cardiopulmonary resuscitation (CPR) and defibrillation (DF). Secondary measures were total scenario score, dangerous actions, proportion of students voicing "ventricular fibrillation," 12-lead ST-elevation myocardial infarction (STEMI) interpretation, and care necessary for return of spontaneous circulation (ROSC). Two expert ACLS instructors scored both performances on a 121-point scale, with each student serving as their own control. We used t tests and McNemar tests for paired data with statistical significance at p<.05.</AbstractText>Before instruction, average time from arrest to CPR was 112 seconds and to first DF 3.01 minutes. Students scored 45±9/121 points and 9/19 (49%) performed dangerous actions. After instruction, time to CPR was 12 seconds (p=004) and to first DF 1.53 minutes (p=.03). Time to DF was delayed as students showed mastery of bag-valve-mask ventilation before DF. After instruction, students scored 97±4/121 points (p<.0001) with no dangerous actions. Before training, only 4 of 19 (21%) students performed both CPR and DF within 2 minutes, and 3 of these had ROSC. After training, 14 of 19 (74%) achieved CPR+DF≤2 minutes (p=.002), and all had ROSC. Before training, 5 of 19 (26%) students said "VF" and 4 of 19 obtained an ECG, but none identified STEMI. After training, corresponding performance was 13 of 19 "VF" (68%, p=021) and 100% ECG and STEMI identification (p<.05).</AbstractText>This course significantly improved knowledge and psychomotor skills. Critical actions required for resuscitation were much more common after training. ACLS training including high-fidelity simulation decreases time to CPR and DF and improves performance during resuscitation.</AbstractText> |
11,671 | Long-term results of single-procedure catheter ablation for atrial fibrillationin pre- and post-menopausal women. | To address whether menopause affects outcome of catheter ablation (CA) for atrial fibrillation (AF) by comparing the safety and long-term outcome of a single-procedure in pre- and post-menopausal women.</AbstractText>A total of 743 female patients who underwent a single CA procedure of drug-refractory AF were retrospectively analyzed. The differences in clinical presentation and outcomes of CA for AF between the pre-menopausal women (PreM group, 94 patients, 12.7%) and the post-menopausal women (PostM group, 649 patients, 87.3%) were assessed.</AbstractText>The patients in the PreM group were younger (P < 0.001) and less likely to have hypertension (P < 0.001) and diabetes (P = 0.005) than those in the PostM group. The two groups were similar with regards to the proportion of concomitant mitral valve regurgitation coronary artery disease, left atrium dimensions, and left ventricular ejection fraction. The overall rate of complications related to AF ablation was similar in both groups (P = 0.385). After 43 (16-108) months of follow-up, the success rate of ablation was 54.3% in the PreM group and 54.2% in the PostM group (P = 0.842). The overall freedom from atrial tachyarrhythmia recurrence was similar in both groups. Menopause was not found to be an independent predictive factor of the recurrence of atrial tachyarrhythmia.</AbstractText>The long-term outcomes of single-procedure CA for AF are similar in pre- and post-menopausal women. Results indicated that CA of AF appears to be as safe and effective in pre-menopausal women as in post-menopausal women.</AbstractText> |
11,672 | Incidence and outcome of re-entry injury in redo cardiac surgery: benefits of preoperative planning. | Repeat sternotomy for redo cardiac surgery may be associated with catastrophic injuries to mediastinal structures. The purpose of this study was to determine the frequency of these injuries, associated outcome and if a preoperative computerized tomography (CT) scan reduces the risk of re-entry injury.</AbstractText>Five hundred and forty-four patients who underwent redo cardiac surgery between 2001 and 2011 were identified by review of our unit's prospectively maintained cardiac surgery database. Demographic details, surgical strategy, re-entry injuries, hospital stay, in-hospital mortality and long-term survival were analysed.</AbstractText>The mean age was 61 years; 326 were male, 218 were female. Four hundred and eighty six patients underwent first time redo surgery, while 58 patients had multiple previous operations. The median logistic EuroSCORE was 11, in-hospital mortality rate was 9.5% and observed to expected mortality rate was 0.8. Re-entry complications occurred in 15 cases (2.7%). These included injuries to the aorta (n = 2), right atrium (n = 1), innominate vein (n = 2), internal mammary artery (n = 2), pulmonary artery (n = 2), lung parenchyma (n = 1), saphenous vein graft (n = 2), right ventricle (n = 2) and ventricular fibrillation (n = 1). The mortality rate in patients with re-entry injury was 26% (n = 4) compared with 9% (n = 48) in those without re-entry complications. Preoperative planning by CT scan was performed in 162 cases and adherence of vital structures to the sternum was found in 60 cases; the right ventricle, innominate vein and bypass grafts in 41, 11 and 8, respectively. The incidence rate of re-entry injury was 0.6% in these patients vs 3.6% in those who did not have a preoperative CT scan (P = 0.046). Peripheral arterial cannulation was carried out in 35 patients (6.4%) to establish cardiopulmonary bypass (CPB) prior to sternotomy, and there were no mediastinal injuries observed in these cases. Multivariate logistic regression analysis revealed re-entry injury as one of the independent predictors of in-hospital mortality (P = 0.039).</AbstractText>The incidence of re-entry injury during repeat sternotomy is low; however, it is associated with a significant increase in the risk of in-hospital mortality. Preoperative planning using CT scan reduces the risk by identifying adherent structures, and, in selected patients, establishing CPB prior to sternotomy is a safe strategy in redo cardiac surgery.</AbstractText>© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.</CopyrightInformation> |
11,673 | Modified Valsalva manoeuvre to treat recurrent supraventricular tachycardia: description of the technique and its successful use in a patient with a previous near fatal complication of DC cardioversion. | Patients with attacks of re-entrant supraventricular tachycardia (SVT) frequently present to the emergency department (ED). The Valsalva manoeuvre (VM) is the most effective and safe vagal manoeuvre and advocated as the first-line treatment in stable patients but has a relatively low cardioversion success rate. Improving its efficacy would reduce patients' exposure to the side effects and complications of second-line treatments and has other potential benefits. We describe a modification to the VM, which is currently being studied, and present the case of a 23-year-old patient who was successfully treated with this modified VM after a previous near-fatal complication of direct current (DC) cardioversion. |
11,674 | Assessment of atrial conduction time in patients with polycystic ovary syndrome. | Polycystic ovary syndrome (PCOS) is closely related to increased cardiovascular risk in women of reproductive age. Atrial conduction abnormalities in these patients have not been investigated in terms of atrial electromechanical delay measured by tissue Doppler imaging (TDI) as an early predictor of atrial fibrillation development. The aim of this study was to evaluate whether TDI-derived atrial conduction time is prolonged in PCOS.</AbstractText>The study included 51 patients with PCOS and 48 age-matched healthy controls. P-wave dispersion (PWD) was calculated on the 12-lead surface electrocardiogram. Systolic and diastolic left ventricular (LV) functions, atrial electromechanical coupling, intraatrial and interatrial electromechanical delays were measured with conventional echocardiography and TDI.</AbstractText>PWD was higher in PCOS women (50.45 ± 3.7 vs 34.73 ± 6.7 ms, p = 0.008). Interatrial and intraatrial electromechanical delay were found longer in patients with PCOS compared to controls (41.9 ± 9.0 vs 22.2 ± 6.6 ms, p < 0.001; 22.6 ± 5.8 vs 5.9 ± 4.7 ms, p < 0.001, respectively). Left atrial (LA) volume index and LV diastolic parameters were significantly different between the groups. PWD was correlated with interatrial electromechanical delay (r = 0.54, p < 0.01). Interatrial electromechanical delay was strongly correlated with homeostatic model assessment insulin resistance index and high-sensitivity C-reactive protein levels (r = 0.68, p < 0.001; r = 0.53, p < 0.001, respectively). Interatrial electromechanical delay was positively correlated with LA volume index and deceleration time (r = 0.31, p = 0.04; r = 0.37, p = 0.021, respectively) and negatively correlated with flow propagation velocity (r = -0.38, p = 0.014).</AbstractText>This study shows that atrial electromechanical delay is prolonged in PCOS patients. Atrial electromechanical delay prolongation is related to low-grade inflammation, insulin resistance, and LV diastolic dysfunction in PCOS.</AbstractText> |
11,675 | Rationale and design of VENTURE-AF: a randomized, open-label, active-controlled multicenter study to evaluate the safety of rivaroxaban and vitamin K antagonists in subjects undergoing catheter ablation for atrial fibrillation. | To evaluate the safety of uninterrupted rivaroxaban, a novel oral anticoagulant that directly inhibits factor Xa, and a vitamin K antagonist (VKA) in eligible adult patients with nonvalvular AF (NVAF) who are scheduled for a catheter ablation.</AbstractText><AbstractText Label="METHODS/DESIGN" NlmCategory="METHODS">This is a prospective, randomized, open-label, active-controlled, global multicenter safety study of up to 250 randomized patients. Eligible patients with paroxysmal or persistent NVAF, a left ventricular ejection fraction >40 %, and a creatinine clearance >50 mL/min will be randomized 1:1 to rivaroxaban 20 mg orally once daily or to dose-adjusted oral VKA (recommended international normalized ratio (INR) 2.0-3.0) and stabilized on anticoagulation therapy for 1-7 days (if no intracardiac thrombus on transesophageal echocardiogram (TEE) immediately prerandomization/post-randomization or if 3 weeks of sufficient anticoagulation is documented) or for 4-5 weeks (if no TEE, no documented 3 weeks of sufficient anticoagulation, or by patient choice). During catheter ablation, heparin will be administered (ACT-targeted range = 300-400 s) after catheter ablation, and VKA will be managed per usual care. The next dose of rivaroxaban will be provided at least 6 h after establishment of hemostasis. The primary endpoint will be the incidence of post-procedure major bleeding events observed during the first 30 ± 5 days post-ablation. Secondary endpoints will include post-procedure thromboembolic events, additional bleeding, time-to-event, and medication adherence.</AbstractText>This study is intended to provide information about the safety characteristics of rivaroxaban in patients with NVAF undergoing catheter ablation.</AbstractText> |
11,676 | Clinical and epidemiological profile of patients with valvular heart disease admitted to the emergency department. | To evaluate the clinical and epidemiological profile of patients with valvular heart disease who arrived decompensated at the emergency department of a university hospital in Brazil.</AbstractText>A descriptive analysis of clinical and echocardiographic data of 174 patients with severe valvular disease, who were clinically decompensated and went to the emergency department of a tertiary cardiology hospital, in the State of São Paulo, in 2009.</AbstractText>The mean age of participants was 56 ± 17 years and 54% were female. The main cause of valve disease was rheumatic in 60%, followed by 15% of degenerative aortic disease and mitral valve prolapse in 13%. Mitral regurgitation (27.5%) was the most common isolated valve disease, followed by aortic stenosis (23%), aortic regurgitation (13%) and mitral stenosis (11%). In echocardiographic data, the mean left atrial diameter was 48 ± 12 mm, 38 ± 12 mm for the left ventricular systolic diameter, and 54 ± 12 mm for the diastolic diameter; the mean ejection fraction was 56 ± 13%, and the mean pulmonary artery pressure was 53 ± 1 6 mmHg. Approximately half of patients (44%) presented atrial fibrillation, and over one third of them (37%) had already undergone another cardiac surgery.</AbstractText>Despite increased comorbidities and age-dependent risk factors commonly described in patients with valvular heart disease, the clinical profile of patients arriving at the emergency department represented a cohort of rheumatic patients in more advanced stages of disease. These patients require priority care in high complexity specialized hospitals.</AbstractText> |
11,677 | Effectiveness of atrial versus atrioventricular pacing for sick sinus syndrome during long-term follow-up. | According to the current guidelines, atrioventricular (DDD) pacing is superior to atrial pacing (AAI) in the treatment of sick sinus syndrome (SSS).</AbstractText>To compare outcomes of AAI and DDD pacing in patients with SSS during long-term follow-up.</AbstractText>We studied 809 patients, including 86 patients in the AAI group (57 women, mean age 65 ± 15 years) and 723 patients in the DDD group (406 women, mean age 71.5 ± 10 years). Evaluation of outcomes of AAI and DDD pacing in SSS was based on the analysis of medical records of patients who underwent pacemaker implantation.</AbstractText>Average duration of follow-up was 52 ± 25 months. In the AAI group, 63 of 86 patients remained without intervention. In the DDD group, 661 of 723 patients did not require surgical intervention. Overall, 105 patients died, including 13 in the AAI group and 92 in the DDD group (p = 0.4516). In the AAI group, a high degree atrioventricular block occurred on average after 46.3 ± 8.8 months and its incidence was estimated at 0.85% per year. Atrial fibrillation (AF) developed in 8 patients in the AAI group and 81 patients in the DDD group (p = 0.23). Among aetiological factors of an increased risk of developing AF, only the presence of tachycardia-bradycardia syndrome (hazard ratio [HR] 11.31) and the absence of antiarrhythmic therapy (HR 4.23) significantly increased the risk of AF. Urgent reoperation was needed in 23 patients in the AAI group and 62 patients in the DDD group (p < 0.01). Log-rank test analysis showed a significant effect of the development of AF on the risk of reoperation in this group (p = 0.0420). Lead-related complications were noted in 6 patients in the AAI group and 49 patients in the DDD group (p = 0.94). After 45 months, the risk of reoperation in the AAI group increased significantly due to a need for ventricular lead implantation.</AbstractText>1. Atrial stimulation is safe in SSS but it may be associated with an increased risk of ventricular lead implantation if atrioventricular block or persistent AF with slow ventricular rate develops. 2. DDD and AAI groups did not differ significantly in terms of survival, development of persistent AF, and lead-related complications. 3. Tachycardia-bradycardia syndrome and the lack of antiarrhythmic treatment with beta-blocker and amiodarone increased the risk of persistent AF during long-term follow-up. 4. A higher rate of reoperations in patients with AAI systems, related mainly to development of persistent AF, especially after the fourth year of follow-up, may justify DDD system implantation in SSS.</AbstractText> |
11,678 | Delayed embolisation of amplatzer ASD closure device caused partial obstruction of left ventricular outflow tract. | A 54-year-old male presented with symptoms of dyspnoea, and oedema of the lower extremities. Transthoracic echocardiography (TTE) revealed secondum-type atrial septal defect (ASD). He successfully received a 30-mm Amplatzer ASD closure device percutaneously. Echocardiography immediately after the procedure and the next day showed a well-positioned device. He was discharged the next day on 100 mg aspirin daily and warfarinisation due to atrial fibrillation. A month later, he revisited the hospital due to recurrence of dyspnoea and a grade 2 systolic murmur was heard on the left parasternal border. A chest X-ray showed abnormal location of the closure device and TTE revealed re-appearance of the ASD and an embolised Amplatzer device in the left ventricular outflow tract (LVOT) with partial obstruction. He requested surgery to remove the Amplatzer device and received an ASD patch repair, tricuspid valve repair and modified Maze operation concurrently. He is now in routine follow up without any other complications. |
11,679 | Simultaneous coronary artery bypass grafting and carotid endarterectomy can be performed with low mortality rates. | There is controversy over the best approach for patients with concomitant carotid and coronary artery disease. In this study, we report on our experience with simultaneous carotid endarterectomy (CEA) and coronary artery bypass graft (CABG) surgery in our clinic in the light of data in the literature.</AbstractText>Between January 1996 and January 2009, a total of 110 patients (86 males, 24 females; mean age 65.11 ± 7.81 years; range 44-85 years), who were admitted to the cardiovascular surgery clinic at our hospital, were retrospectively analysed. All patients underwent simultaneous CEA and CABG. Demographic characteristics of the patients and a history of previous myocardial infarction (MI), hypertension, diabetes mellitus, hyperlipidaemia, peripheral arterial disease and smoking were recorded.</AbstractText>One patient (0.9%) with major stroke died due to ventricular fibrillation. Peri-operative neurological complications were observed in seven patients (6%). Complications were persistent in two patients. Four patients (3%) had postoperative major stroke, whereas three patients (2%) had transient hemiparesis. No peri-operative myocardial infarction was observed.</AbstractText>Simultaneous CEA and CABG can be performed with low rates of mortality and morbidity.</AbstractText> |
11,680 | The potential mechanism of the detrimental effect of defibrillation prior to cardiopulmonary resuscitation in prolonged cardiac arrest model. | Defibrillation is no longer universally recommended as initial intervention for the reversal of ventricular fibrillation (VF) after a prolonged and untreated cardiac arrest. We sought to examine this issue in an animal model where a prolonged untreated VF was induced. The aim of this study was to investigate the potential mechanism of the detrimental effect of defibrillation prior to cardiopulmonary resuscitation (CPR) in prolonged cardiac arrest model. VF was electrically induced in 32 domestic male swine weighing 40±3 kg and remained untreated for 15 minutes. The animals were then randomly allocated to either the initial defibrillation group or the chest compression group. Mean aortic pressure, right atrial pressure and coronary perfusion pressure (CPP) were continuously measured during the performance. The dimensions of the left ventricle (LV) were assessed by echocardiographic methods. The CPP induced by CPR after defibrillation was significantly lower in the initial defibrillation group than in the chest compression group; 1 minute after defibrillation (9±3 mmHg vs. 14.8±7 mmHg (P<0.05)), and after 5 minutes 16±5 mmHg vs. 21.7±1 mmHg (P<0.05). The LV volumes were reduced from 18±2 mmHg to 14±1 mmHg after defibrillation (P<0.05). In brief, this study showed that the conducting defibrillation prior to chest compression may cause a contracture of the LV, resulting in lowering CPP, thus dropping the efficiency of chest compression in a prolonged cardiac arrest model. |
11,681 | Cardiovascular complications of calcium supplementation in chronic kidney disease: are there arrhythmic risks? | Calcium supplements may induce hypercalcaemia in patients with chronic kidney disease (CKD) or patients on hemodialysis. Even in the absence of overt hypercalcaemia, calcium supplementation may be associated with a positive calcium balance and intracellular calcium overload. There is an increased risk of complex supraventricular, ventricular arrhythmias or the risk of suffering a cardiac arrest in the presence of hypercalcaemia and calcium overload in subjects with impaired or absent renal function. A maximum intake of 1000 mg elemental calcium, combining supplements and dietary calcium, together with a 1.5 mmol/l level in the dialysate, may be a safer (opinion based) recommendation in CKD patients. This is especially the case if the patient already shows signs of extra-skeletal calcification or if they present cardiac comorbidities. Lower calcium levels in the dialysis fluid might reduce the positive calcium balance but can increase intradialytic plasma calcium changes and therefore increase the risk of arrhythmias. |
11,682 | Anomalous origin of the right coronary artery from the pulmonary artery diagnosed in an adult: A case report. | Anomalous origin of the right coronary artery (ARCA) from the main pulmonary artery is a rare congenital anomaly, unlike the well-known anomalous origin of the left coronary artery (Bland-White-Garland syndrome) from the pulmonary artery. Since most ARCA cases are diagnosed during childhood, few adult cases have been reported. We describe the case of a patient who demonstrated ventricular arrhythmia and low cardiac function due to ischemic heart disease and an ARCA. Coronary angiography revealed flow from the left coronary artery to the pulmonary artery via an epicardial collateral artery and the right coronary artery. Multidetector-row computed tomography provided a definitive diagnosis of ARCA; the patient underwent surgical revascularization. <<b>Learning objective:</b> We incidentally diagnosed ARCA in a patient who experienced ventricular fibrillation. ARCA is a rare condition caused by early-onset cardiac ischemia, which may be a differential diagnosis for this congenital anomaly. Multidetector-row computed tomography is useful for detecting ARCA and determining the coronary artery's course and other congenital anomalies. Immediate surgical treatment for ARCA is strongly recommended to prevent sudden cardiac death.>. |
11,683 | Hypertrophic cardiomyopathy: present and future, with translation into contemporary cardiovascular medicine. | Hypertrophic cardiomyopathy (HCM) is a common inherited heart disease with diverse phenotypic and genetic expression, clinical presentation, and natural history. HCM has been recognized for 55 years, but recently substantial advances in diagnosis and treatment options have evolved, as well as increased recognition of the disease in clinical practice. Nevertheless, most genetically and clinically affected individuals probably remain undiagnosed, largely free from disease-related complications, although HCM may progress along 1 or more of its major disease pathways (i.e., arrhythmic sudden death risk; progressive heart failure [HF] due to dynamic left ventricular [LV] outflow obstruction or due to systolic dysfunction in the absence of obstruction; or atrial fibrillation with risk of stroke). Effective treatments are available for each adverse HCM complication, including implantable cardioverter-defibrillators (ICDs) for sudden death prevention, heart transplantation for end-stage failure, surgical myectomy (or selectively, alcohol septal ablation) to alleviate HF symptoms by abolishing outflow obstruction, and catheter-based procedures to control atrial fibrillation. These and other strategies have now resulted in a low disease-related mortality rate of <1%/year. Therefore, HCM has emerged from an era of misunderstanding, stigma, and pessimism, experiencing vast changes in its clinical profile, and acquiring an effective and diverse management armamentarium. These advances have changed its natural history, with prevention of sudden death and reversal of HF, thereby restoring quality of life with extended (if not normal) longevity for most patients, and transforming HCM into a contemporary treatable cardiovascular disease. |
11,684 | Regional variations in baseline characteristics of cardiac rhythm device recipients: The PANORAMA observational cohort study. | The PANORAMA study was designed to collect concurrent data on subjects from different worldwide regions implanted with CRM devices.</AbstractText>In this prospective, multi-center study, we analyzed baseline data on 8586 subjects implanted with CRM devices with no additional selection criteria (66% pacemaker (IPG), 16% implantable cardiac defibrillators (ICD), 17% cardiac resynchronization therapy (CRT) and < 1% Internal Loop Recorder) from 156 hospitals across 6 geographical regions between 2005 and 2011.</AbstractText>Regardless of the device implanted, subjects from the Middle East and India often had more diabetes than other regions. Eastern and Western Europe had higher rates of atrial fibrillation reported, and men were more likely to smoke than women (46% vs 11%, p < 0.001). Within the CRT cohort there was significant variation in the proportion of males receiving a device, ranging from 55% in India to 83% in Eastern Europe.</AbstractText>We provide comprehensive descriptive data on patients receiving CRM devices from a range of geographies that are not typically reported in literature. We found significant variations in clinical characteristics and implant practices. Long term follow-up data will help evaluate if these variations require adjustments to outcome expectations.</AbstractText> |
11,685 | Cardiac arrest: should we consider norepinephrine instead of epinephrine? | A patient scheduled for a laparoscopic cholecystectomy had an anaphylactic shock during induction of anesthesia. After the injection of vecuronium, an unusual fall of arterial pressure occurred, with bradycardia, enlargement of the QRS complex, then a circulatory arrest. Chest compressions were initiated, while intravenous epinephrine 1 mg was administered. The cardiac rhythm turned into a ventricular fibrillation (VF). Despite continuous chest compressions with repeated boluses of epinephrine and several external electric shocks, the patient remained in VF. Because of obviously β-adrenergic adverse effects, epinephrine was replaced with norepinephrine. Return of spontaneous circulation was observed, with the recovering of sinusal activity. After staying for several weeks in intensive care unit because of multiorgan failure, the patient recovered without sequelae. Blood samples and cutaneous testing confirmed an allergy to vecuronium. This case report of a cardiac anaphylaxis with prolonged cardiac arrest illustrates the dual activity and adverse effects of epinephrine. Although vasoconstriction is mandated during cardiopulmonary resuscitation to provide an acceptable perfusion pressure to organs, β-adrenergic stimulation seems deleterious to the heart. Experimental studies have shown that blocking the β-adrenergic effects of epinephrine attenuates postresuscitation myocardial dysfunction or helps the return of spontaneous circulation after VF. Norepinephrine, a potent α-adrenergic drug nearly devoid of β-adrenergic properties, could be an interesting alternative to epinephrine. It can improve organ perfusion during cardiopulmonary resuscitation and could be more efficient than epinephrine in case of VF. |
11,686 | [P wave dispersion increased in childhood depending on blood pressure, weight, height, and cardiac structure and function]. | Increased P wave dispersion are identified as a predictor of atrial fibrillation. There are associations between hypertension, P wave dispersion, constitutional and echocardiographic variables. These relationships have been scarcely studied in pediatrics.</AbstractText>The aim of this study was to determine the relationship between P wave dispersion, blood pressure, echocardiographic and constitutional variables, and determine the most influential variables on P wave dispersion increases in pediatrics.</AbstractText>In the frame of the PROCDEC II project, children from 8 to 11 years old, without known heart conditions were studied. Arterial blood pressure was measured in all the children; a 12-lead surface electrocardiogram and an echocardiogram were done as well.</AbstractText>Left ventricular mass index mean values for normotensive (25.91±5.96g/m(2.7)) and hypertensive (30.34±8.48g/m(2.7)) showed significant differences P=.000. When we add prehypertensive and hypertensive there are 50.38% with normal left ventricular mass index and P wave dispersion was increased versus 13.36% of normotensive. Multiple regression demonstrated that the mean blood pressure, duration of A wave of mitral inflow, weight and height have a value of r=0.88 as related to P wave dispersion.</AbstractText>P wave dispersion is increased in pre- and hypertensive children compared to normotensive. There are pre- and hypertensive patients with normal left ventricular mass index and increased P wave dispersion. Mean arterial pressure, duration of the A wave of mitral inflow, weight and height are the variables with the highest influence on increased P wave dispersion.</AbstractText>Copyright © 2013 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.</CopyrightInformation> |
11,687 | Electrocardiographic predictors of sudden and non-sudden cardiac death in patients with ischemic cardiomyopathy. | This study evaluated the prognostic value of electrocardiogram (ECG)-based predictors in the primary prevention of sudden cardiac arrest (SCA) among ischemic cardiomyopathy patients with depressed left ventricular ejection fraction (LVEF ≤35%).</AbstractText>The prediction of cause-specific mortality in high-risk patients offers the potential for targeting specific therapies (i.e., implantable cardioverter-defibrillator [ICD]).</AbstractText>Subjects were recruited from the Prediction of Arrhythmic Events with Positron Emission Tomography (PAREPET) study. Continuous Holter 12-lead ECG recordings were obtained at the start of study and used to compute 15 clinically-important ECG abnormalities (e.g., atrial fibrillation).</AbstractText>Among 197 patients (age 67 ± 11 years, 93% male, mean follow-up 4.1 years) enrolled, 30 (15%) were SCA cases and 35 (18%) cardiac non-sudden deaths (C/NS). In multivariate analysis, only heart-rate-corrected QT interval (QTc) predicted SCA (hazard ratio 2.9 [1.2-7.3]) and only depressed heart rate variability (HRV) predicted C/NS (hazard ratio 5.0 [1.5-17.1]) independent of demographic and clinical parameters.</AbstractText>Among patients with depressed LVEF, prolonged QTc suggests greater potential benefit from ICD therapy to prevent SCA; depressed HRV suggests potential benefit from bi-ventricular pacing to prevent C/NS.</AbstractText>Copyright © 2014 Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,688 | Predictive factors of left atrial spontaneous echo contrast in patients with rheumatic mitral valve stenosis: a retrospective study of 159 patients. | Mitral valve stenosis is a common manifestation of chronic rheumatic heart disease. The presence of spontaneous echo contrast in the left atrium and left atrial appendage has been reported to be an independent predictor of thrombo-embolic risk in patients with mitral stenosis. The objective of this study was to retrospectively investigate various clinical and echocardiographic variables to predict the spontaneous echo contrast in these patients.</AbstractText>This is a bicentric retrospective study which includes 159 cases of symptomatic mitral stenosis from January 2011 to June 2012. All of the patients had transthoracic and transesophageal echocardiography. Patients who had significant mitral regurgitation (> Grade I), significant aortic valve disease, previous mitral valvulotomy and anticoagulation or antiplatelet therapy were excluded from the study. Our study population was divided into two groups based on the presence (Group I) or absence (Group II) of spontaneous echo contrast.</AbstractText>Left atrial spontaneous contrast was present in 34.6% of cases. Patients in this group have more frequent atrial fibrillation (P = 0.001), larger left atrial area (P = 0.027) and diameter (P=0.023), smaller mitral valve area (P = 0.025), and higher mean transmitral diastolic gradient (p = 0.003) as compared to patients without spontaneous echo contrast. There were no significant differences in the mean age (p = 0.38), duration of symptoms (p = 0.4) and left ventricular ejection fraction (p = 0.7) between patients with and without spontaneous echo contrast. On multivariate analysis, only mitral valve area and transmitral diastolic gradient (OR: 18.753, 1.21, CI [1,838-191,332], [1,064-1,376], p: 0.013, 0.004, respectively) were found to be independently associated to the presence of spontaneous echo contrast.</AbstractText>Patients with severe rheumatic mitral stenosis in atrial fibrillation or sinus rhythm have a higher risk of developing spontaneous echo contrast. These patients might benefit from prophylactic anticoagulation. The long-term outcomes can be ascertained in a study over a longer period and with periodic follow-up.</AbstractText> |
11,689 | Early experience with the subcutaneous ICD. | The Subcutaneous Internal Cardiac Defibrillator (S-ICD) represents a major advance in the care of patients who have an indication for an internal cardiac defibrillator without pacing indications. Its main advantage is that it can deliver a shock to cardiovert ventricular arrhythmias utilising a tunnelled subcutaneous lead, negating the risks associated with conventional transvenous systems. Initial studies have shown comparable efficacy in cardioversion of induced and spontaneous ventricular tachycardia (VT) and ventricular fibrillation (VF) when compared to conventional transvenous systems. In addition, inappropriate shocks occurred in a similar percentage of patients to conventional ICD studies. Complication rates are low and relate largely to localised wound infections, treated successfully with antibiotics. The long term efficacy of the device is yet to be ascertained, however, a randomised trial & prospective registries are currently in progress to enable direct comparison with transvenous ICDs. This article summarises the early clinical experience and trials in the implantation of the S-ICD. |
11,690 | Evaluation of the need of elective implantable cardioverter-defibrillator generator replacement in primary prevention patients without prior appropriate ICD therapy. | It is not clear whether patients who received an implantable cardioverter-defibrillator (ICD) for primary prevention should undergo device replacement if they never experienced an appropriate ICD therapy during the first generator longevity. This study evaluated the incidence and predictors of appropriate ICD therapy after device replacement in this specific population.</AbstractText>From two large prospective ICD registries, we identified all primary prevention patients who had a first ICD replacement without previous appropriate ICD therapy. Cox regression analysis was used to identify predictors of appropriate ICD therapy.</AbstractText>Of 403 primary prevention patients needing first ICD replacement, 275 patients (68%) had not received previous appropriate ICD therapy. Patients without previous appropriate ICD therapy before first ICD replacement (mean age at replacement 62 ± 12 years, 75% male) had a mean follow-up of 86 ± 24 months after the initial implantation and 30 ± 24 months after device replacement. Following replacement, 3-year cumulative incidence of appropriate ICD therapy was 13.7% (95% CI 8.6 to 18.8%). No predictive factors associated with appropriate ICD therapy after replacement could be identified in spite of including seven clinically relevant factors.</AbstractText>A considerable number of primary prevention patients without previous appropriate ICD therapy before first ICD replacement received appropriate ICD therapy after replacement. As there were no predictors of appropriate ICD therapy after replacement, replacing an ICD is still recommended in all primary prevention patients despite the lack of appropriate ICD therapy during first battery service life.</AbstractText>Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.</CopyrightInformation> |
11,691 | Prognostic value of the electrocardiogram in patients with syncope: data from the group for syncope study in the emergency room (GESINUR). | The Group for Syncope Study in the Emergency Room (GESINUR) was a Spanish multicenter, prospective, observational study that evaluated the clinical presentation and acute management of loss of consciousness in Spain. Several studies have shown that an abnormal ECG is a poor prognostic factor in patients with syncope. However, the prognostic significance of each ECG abnormality is not well known.</AbstractText>The purpose of this study was to study the association between specific ECG abnormalities and mortality in patients with syncope from the GESINUR study.</AbstractText>All patients in the GESINUR study who had syncope and had available, readable ECG and 12-month follow-up data were included in this retrospective observational study (n = 524, age 57 ± 22 years, 50.6% male). ECG abnormalities were analyzed and assessed to evaluate whether an association with all-cause mortality existed at 12 months.</AbstractText>ECGs were classified as abnormal in 344 patients (65.6%). Thirty-three patients died during follow-up (6.3%), but only 1 due to sudden cardiovascular death. Atrial fibrillation (odds ratio [OR] 6.8, 95% confidence interval [CI] 2.8-16.3, P <.001), intraventricular conduction disturbances (OR 3.8, 95% CI 1.7-8.3, P = .001), left ventricular hypertrophy ECG criteria (OR 6.3, 95% CI 1.5-26.3, P = .011), and ventricular pacing (OR 21.8, 95% CI 4.1-115.3, P <.001) were the only independent ECG predictors of all-cause mortality.</AbstractText>Although an abnormal ECG in patients with syncope is a common finding, only the presence of atrial fibrillation, intraventricular conduction disturbances, left ventricular hypertrophy ECG criteria, and ventricular pacing is associated with 1-year all-cause mortality.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,692 | [Case with Emery-Dreifuss muscular dystrophy diagnosed forty-two years after onset and implanted with a cardiac resynchronization therapy defibrillator]. | The patient was a 53-year-old male. He showed steppage gait at the age of 11 and equinus foot at 13. He walked unaided with shoe-insoles to support his heels. Atrial fibrillation and cardiac hypertrophy were found in his 30s, and ventricular tachycardia (VT) was observed at the age of 48. Electrophysiological studies were performed, but VT was not sustained, symptomatic, or showed signs of infra-Hisian block, and a pacemaker was not indicated. At 53, he was introduced to a neurologist because of tetraplegia after the first episode of syncope. A spinal MR showed ossification of posterior longitudinal ligament (OPLL) and central cervical cord injury. Furthermore, he presented not only contracture in his shoulder, elbow, and ankles but also atrophy in his scapulohumeral and gastrocnemius muscles. In accordance with a diagnosis of Emery-Dreifuss muscular dystrophy (EDMD), provocative testing of VT was carried out, and a cardiac resynchronization therapy defibrillator (CRT-D) was implanted. Later, a mutation analysis of the LMNA gene disclosed a known missense mutation of p.Arg377His, and we diagnosed him as EDMD2 (laminopathy). Contractures could be the clue to diagnose EDMD and indicate the need for pacemakers and defibrillators in patients with cardiac conduction disorders. |
11,693 | Arrhythmia and thyroid dysfunction. | Arrhythmia is a major cause of morbidity and mortality in Europe and in the United States. The aim of this review article was to assess the results of the prospective studies that evaluated the risk of arrhythmia in patients with overt and subclinical thyroid disease and discuss the management of this arrhythmia.</AbstractText>A literature search was carried out for reports published with the following terms: thyroid, hypothyroidism, hyperthyroidism, subclinical hyperthyroidism, subclinical hypothyroidism, levothyroxine, triiodothyronine, antithyroid drugs, radioiodine, deiodinase, atrial flutter, supraventricular arrhythmia, ventricular arrhythmia, ventricular tachycardia, ventricular fibrillation, torsade de pointes, amiodarone and atrial fibrillation. The investigation was restricted to reports published in English.</AbstractText>The outcome of this analysis suggests that patients with untreated overt clinical or subclinical thyroid dysfunction are at increased risk of arrhythmia. Hyperthyroidism increased atrial arrhythmia; however, hypothyroidism increased ventricular arrhythmia.</AbstractText>The early recognition and effective treatment of thyroid dysfunction in patients with arrhythmia is mandatory because the long-term prognosis of arrhythmia may be improved with the appropriate treatment of thyroid dysfunction.</AbstractText> |
11,694 | Acute effects of simvastatin to terminate fast reentrant tachycardia through increasing wavelength of atrioventricular nodal reentrant tachycardia circuit. | Simvastatin (SV) leads to reduction of ventricular rhythm during atrial fibrillation on rabbit atrioventricular (AV) nodes. The aim of our study was (i) to determine the frequency-dependent effects of SV in a functional model, and (ii) to assess the effects of SV to suppress experimental AV nodal reentrant tachycardia (AVNRT). Selective stimulation protocols were used with two different pacing protocols, His to atrial, and atrial to atrial (AA). An experimental AVNRT model with various cycle lengths was created in three groups of perfused rabbit AV nodal preparations (n = 24) including: SV 3 μm, SV 7 μm, and verapamil 0.1 μm. SV increased nodal conduction time and refractoriness by AA pacing. Different simulated models of slow/fast and fast/slow reentry were induced. SV caused inhibitory effects on the slow anterograde conduction (origin of refractoriness) more than on the fast anterograde conduction time, leading to an increase of tachycardia cycle length, tachycardia wavelength and termination of slow/fast reentrant tachyarrhythmia. Verapamil significantly suppressed the basic and frequency-dependent intrinsic nodal properties. In addition, SV decreased the incidence of gap and echo beats. The present study showed that SV in a concentration and rate-dependent manner increased the AV effective refractory period and reentrant tachycardia wavelength that lead to slowing or termination of experimental fast AVNRT. The direction-dependent inhibitory effect of SV on the anterograde and retrograde dual pathways explains its specific antireentrant actions. |
11,695 | Circadian rhythm and day to day variability of serum potassium concentration: a pilot study. | Hyperkalemia is a common and life-threatening complication frequently seen in patients with acute kidney injury, end-stage renal disease and chronic heart failure. Cardiac arrest and ventricular fibrillation are possible consequences. Biosensors are currently being developed to measure serum potassium under ambulatory conditions and trigger an alarm if the potassium concentration exceeds normal limits. Only few studies exist on the circadian rhythm of potassium; and its dependence on age and kidney function is less clear.</AbstractText>Our observational monocentric exploratory study included 30 subjects of which 15 had impaired renal function (RF) (GFR <60 ml/min/1.73 m(2)). Subjects were further categorized into three age groups: 18-39 years (N normal RF = 5, N impaired RF = 4), 40-59 years (N normal RF = 5, N impaired RF = 6), 60-80 years (N normal RF = 5, N impaired RF = 5). Serum potassium levels were measured every 2 h during a 24 h period and repeated once after 2, 4, or 6 days.</AbstractText>In the 15 subjects with normal RF, the lowest mean potassium level (3.96 ± 0.14 mmol/l) was observed at 9 p.m. and the greatest (4.23 ± 0.23 mmol/l) at 1 p.m. In patients with impaired RF the lowest mean potassium level (4.20 ± 0.32 mmol/l) was observed at 9 p.m. and the highest (4.57 ± 0.46 mmol/l) at 3 p.m. The range between the mean of minimum and maximum was greater in patients with impaired RF (0.71 ± 0.45 mmol/l) than in subjects with normal RF (0.53 ± 0.14 mmol/l) [p < 0.001]. No difference in the circadian rhythm was found between the first and second examination.</AbstractText>Our results indicate that patients with normal and impaired RF have comparable circadian patterns of serum potassium concentrations, but higher fluctuations in patients with impaired RF. These results have clinical relevance for developing an automatic biosensor to measure the potassium concentration in blood under ambulatory conditions in patients at high risk for potassium fluctuations.</AbstractText> |
11,696 | [Catheter renal denervation in treatment of resistant hypertension: reality or fiction?]. | Catheter renal denervation is one of the most dynamically emerging subspecialties in cardiology in the last five years. Initial indications for the treatment of resistant hypertension have been extended to other research areas - sleep apnea syndrome, heart failure, insulin resistance, atrial fibrillation, ventricular tachycardias and many others. Just as in other areas of cardiology, for example, the issue of stem cells, was unfortunately little space devoted to experimental studies and clinical studies phase II. Clinical application was ahead of a substantial part of the development of new technologies. Originally Symplicity HTN-1 and -2 showed promising results, now have been recently challenged by early termination of the Symplicity HTN-3 study, which had significantly harder endopoints than previous studies. What was the precise cause of the inefficiency of this treatment, it is currently impossible to say exactly. Interesting conclusions could bring original Czech study PRAGUE 15, designed by professor Petr Widimský, where control treatment in both arms is verified by gold standard - ambulatory blood pressure monitoring and as well emphasis the compliance of the pharmacology treatment. |
11,697 | Prognostic stratification of patients with chronic systolic heart failure using biomarkers and Doppler echocardiography. | To verify whether a combined assessment of left-ventricular filling pattern at Doppler echocardiography, plasma levels of brain natriuretic peptide (BNP) and high-sensitive troponin I (hsTnI) improves prognostic stratification in patients with chronic systolic heart failure.</AbstractText>Three predictors of prognosis were evaluated in 200 consecutive outpatients with heart failure and left-ventricular ejection fraction 35% or less: left-ventricular filling pattern at Doppler echocardiography, BNP plasma levels and hsTnI plasma levels.</AbstractText>During a median follow-up period of 44 months, 15 deaths, two urgent cardiac transplantations, two episodes of ventricular fibrillation and 50 heart failure hospitalizations were observed. The end point of survival analysis was the composite of hard events and hospitalization for acute heart failure. At univariable analysis, the E-wave deceleration time at Doppler echocardiography and BNP plasma level on a continuous log-scale were significantly associated with event-free survival, whereas hsTnI plasma level was not statistically significant. A hierarchical multivariable analysis was performed including a restrictive left-ventricular filling pattern at Doppler as the first prognostic indicator; the subsequent addition of BNP plasma levels above 138  pg/ml (median value) and hsTnI above 0.018  ng/ml (median value) did not further improve prognostic stratification.</AbstractText>A restrictive left-ventricular filling pattern at Doppler echocardiography is the most important prognostic indicator in chronic heart failure patients. Plasma levels of BNP and hsTnI do not provide additional relevant information to identify patients at higher risk of cardiovascular outcomes.</AbstractText> |
11,698 | Polymorphisms of β 1-adrenoreceptor gene and cardiovascular complications in patients with thyrotoxicosis. | Human cardiac β 1-AR perform a crucial role in mediating the cardiostimulating effects of norepinephrine. Gly389Arg and Ser49Gly polymorphisms of β 1-adrenoreceptors ( β 1-AR) can influence the cardiovascular prognosis. However, the possible effect of Gly389Arg and Ser49Gly polymorphisms on heart function in thyrotoxicosis has not been studied. We investigated the possible link between Gly389Arg and Ser49Gly polymorphisms and echocardiography parameters in 165 normotensive patients with a thyrotoxicosis without any cardiovascular disorders. Echo-CG was performed according to standard protocol before and during the thyreostatic treatment. Our data demonstrate that both Gly389Arg and Ser49Gly polymorphisms have very moderate influence on the risk of left ventricular hypertrophy and atrial fibrillation with no statistically significant effects on cardiac function and the development of cardiovascular complications. |
11,699 | Long-term prognosis in patients with Brugada syndrome based on Class II indication for implantable cardioverter-defibrillator in the HRS/EHRA/APHRS Expert Consensus Statement: multicenter study in Japan. | The HRS/EHRA/APHRS Expert Consensus Statement for implantable cardioverter-defibrillator (ICD) in Brugada syndrome (BrS) has recently been published. However, the validity of the Class II indication for ICD in BrS patients is still unknown.</AbstractText>The purpose of this study was to evaluate the validity of the Class II indication for ICD implantation in the Consensus Statement with a large Japanese cohort of BrS.</AbstractText>Among 410 patients with BrS, a total of 213 consecutive BrS patients with the Class II indication for ICD implantation (mean age 53 ± 14 years, 199 men) were enrolled. Clinical outcomes were compared between patients with Class IIa (n = 66) and those with Class IIb (n = 147) indication according to the Consensus Statement.</AbstractText>The incidence of cardiac events (documented ventricular tachyarrhythmias or sudden cardiac death) during follow-up of 62 ± 34 months was significantly higher in patients with Class IIa (n = 8, 2.2% per year) than those with Class IIb indication (n = 4, 0.5% per year; P = .01).</AbstractText>We confirmed that Class IIa indication identified a group of patients with increased risk compared to Class IIb indication for ICD in the Consensus Statement of 2013. In patients with Class II indication, the combination of a history of syncope and spontaneous type 1 ECG may be an important factor in distinguishing intermediate- from low-risk patients with BrS in Japan.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
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