| [ | |
| { | |
| "slide_number": 1, | |
| "slide_title": "The Heart", | |
| "chunk_id": "slide1_chunk0", | |
| "text": "The Heart Unit 3" | |
| }, | |
| { | |
| "slide_number": 2, | |
| "slide_title": "Syllabus of unit 3", | |
| "chunk_id": "slide2_chunk0", | |
| "text": "Syllabus of unit 3 Anatomy of Heart, Heart Valve and Circulation of Blood, Properties of Cardiac Muscles, Conduction System, Cardiac Cycle, Heart Sounds, Cardiac Output, Regulation of Heart Rate, Blood Pressure and Its Regulation. Electrocardiogram. Structure and Function of Blood Vessels-Artery, Vein and Capillaries, Capillary Exchange, Factors Affecting Blood Flow, Development of Blood Vessels." | |
| }, | |
| { | |
| "slide_number": 3, | |
| "slide_title": "Cardiovascular system", | |
| "chunk_id": "slide3_chunk0", | |
| "text": "Cardiovascular system Cardio + vascular : it involves all the blood, blood vessels and heart which pumps the blood through blood vessels. The cardiovascular system contributes to homeostasis of other body systems by transporting and distributing blood throughout the body to deliver materials (such as oxygen, nutrients, and hormones) and carry away wastes. The scientific study of the normal heart and the diseases associated with it is cardiology." | |
| }, | |
| { | |
| "slide_number": 4, | |
| "slide_title": "", | |
| "chunk_id": "slide4_chunk0", | |
| "text": "Amazing Facts about the Human Heart The heart is about the same size as your fist. The heart beats on average 70 times per minute; 4,200 beats per hour; 100,000 beats per day; 365 million beats per year; 30 billion beats in an average life time of 80 years. An adult heart pumps 7,500 liters of blood daily. It takes about 20 seconds to pump blood to every cell in your body. If you lined up all the blood vessels in your body end-to-end, they would wrap around the earth twice." | |
| }, | |
| { | |
| "slide_number": 5, | |
| "slide_title": "Anatomy of heart", | |
| "chunk_id": "slide5_chunk0", | |
| "text": "Anatomy of heart The heart rests on the diaphragm, near the midline of the thoracic cavity. The heart lies in the mediastinum, an anatomical region that extends from the sternum to the vertebral column, from the first rib to the diaphragm, and between the lungs. Heart is covered by a membrane called pericardium. Apex of heart Base of heart Diaphragm" | |
| }, | |
| { | |
| "slide_number": 6, | |
| "slide_title": "Pericardium", | |
| "chunk_id": "slide6_chunk0", | |
| "text": "Pericardium The membrane that surround and protects the heart. It confines the heart into its position in the mediastinum, while allowing sufficient movement for vigorous and rapid contraction. It consists of 2 parts: Fibrous pericardium and Serous pericardium Superficial Fibrous pericardium: Composed of tough, inelastic, dense irregular connective tissue. Its open end is fused to the connective tissues of the blood vessels entering and leaving the heart. It prevents the out stretching of heart, provides protection, and anchors the heart in mediastinum. At apex it is slightly fused with diaphragm." | |
| }, | |
| { | |
| "slide_number": 7, | |
| "slide_title": "Pericardium", | |
| "chunk_id": "slide7_chunk0", | |
| "text": "Pericardium Serous pericardium Thinner, more delicate membrane that forms a double layer around heart. The outer parietal layer of the serous pericardium is fused to the fibrous pericardium. The inner visceral layer of serous pericardium- epicardium Between the two layer is a space that contains a few milliliters of pericardial fluid called pericardial cavity. This fluid helps in reduction of friction between the layers of serous pericardium as heart moves." | |
| }, | |
| { | |
| "slide_number": 8, | |
| "slide_title": "Layers of heart", | |
| "chunk_id": "slide8_chunk0", | |
| "text": "Layers of heart Walls of heart has 3 layers: Epicardium The epicardium is composed of two tissue layers. The outermost is called the visceral layer of the serous pericardium. It houses major coronary and cardiac vessels of the heart. Myocardium Responsible for pumping action of heart and composed of cardiac muscle tissue. Endocardium A thin layer of endothelium overlying a thin layer of connective tissue. It provides the smooth lining for the chambers of the heart and covers the valves of heart." | |
| }, | |
| { | |
| "slide_number": 10, | |
| "slide_title": "", | |
| "chunk_id": "slide10_chunk0", | |
| "text": "Sulci: series of grooves that contains coronary blood vessels and variable amount of fat. Each sulcus marks the external boundary between two chambers Coronary sulcus- marks the external boundary between the superior atria and inferior ventricles Anterior interventricular sulcus Posterior interventricular sulcus" | |
| }, | |
| { | |
| "slide_number": 11, | |
| "slide_title": "Chambers of heart", | |
| "chunk_id": "slide11_chunk0", | |
| "text": "Chambers of heart" | |
| }, | |
| { | |
| "slide_number": 12, | |
| "slide_title": "Comparison of left and right ventricles", | |
| "chunk_id": "slide12_chunk0", | |
| "text": "Comparison of left and right ventricles" | |
| }, | |
| { | |
| "slide_number": 13, | |
| "slide_title": "Fibrous skeleton of heart", | |
| "chunk_id": "slide13_chunk0", | |
| "text": "Fibrous skeleton of heart A dense connective tissue that forms fibrous skeleton of heart. There are 4 rings that surrounds the valve and form structural foundation of heart valve. It prevents overstretching of valves as blood passes through them. Act as an electrical insulator between the atria and ventricles." | |
| }, | |
| { | |
| "slide_number": 14, | |
| "slide_title": "Heart valves", | |
| "chunk_id": "slide14_chunk0", | |
| "text": "Heart valves Heart valves open and close as response to pressure changes as heart contracts and relaxes. Ensure one way flow of blood Regurgitation" | |
| }, | |
| { | |
| "slide_number": 15, | |
| "slide_title": "Systemic and pulmonary circulation", | |
| "chunk_id": "slide15_chunk0", | |
| "text": "Systemic and pulmonary circulation" | |
| }, | |
| { | |
| "slide_number": 16, | |
| "slide_title": "Coronary circulation and collateral circulation", | |
| "chunk_id": "slide16_chunk0", | |
| "text": "Coronary circulation and collateral circulation Anastomoses Collateral circulation Reperfusion- blockage of coronary artery deprive heart muscles from oxygen" | |
| }, | |
| { | |
| "slide_number": 17, | |
| "slide_title": "Muscle tissue", | |
| "chunk_id": "slide17_chunk0", | |
| "text": "Muscle tissue" | |
| }, | |
| { | |
| "slide_number": 18, | |
| "slide_title": "How much you know?", | |
| "chunk_id": "slide18_chunk0", | |
| "text": "How much you know? Define the terms? Auricle Atria Aorta Ventricle Papillary muscles Name of all 4 valves Chordae tendineae Coronary vein Pulmonary vein Systemic flow Pulmonary circulation Coronary circulation" | |
| }, | |
| { | |
| "slide_number": 20, | |
| "slide_title": "", | |
| "chunk_id": "slide20_chunk0", | |
| "text": "Cardiac Muscle" | |
| }, | |
| { | |
| "slide_number": 21, | |
| "slide_title": "Cardiac Muscle", | |
| "chunk_id": "slide21_chunk0", | |
| "text": "Cardiac Muscle They are shorter in length and less circular in transvers section. Exhibit branching The ends of cardiac muscle fibers connect to neighboring fibers by irregular transvers thickenings of the sarcolemma called intercalated disk. The disk contains desmosomes and gap junctions. Large numbers of mitochondria (25%). Small sarcoplasmic reticulum indicates less storage of calcium ions." | |
| }, | |
| { | |
| "slide_number": 23, | |
| "slide_title": "Auto rhythmic fibers", | |
| "chunk_id": "slide23_chunk0", | |
| "text": "Auto rhythmic fibers “Surgeons are better plumbers than electricians” ANS and epinephrine can modify the timing and strength of each heart beat." | |
| }, | |
| { | |
| "slide_number": 24, | |
| "slide_title": "Auto rhythmic fibers", | |
| "chunk_id": "slide24_chunk0", | |
| "text": "Auto rhythmic fibers On their own, auto rhythmic fibers in the SA node would initiate an action potential about every 0.6 second, or 100 times per minute. Thus, the SA node sets the rhythm for contraction of the heart—it is the natural pacemaker. This rate is faster than that of any other auto rhythmic fibers. Because action potentials from the SA node spread through the conduction system and stimulate other areas before the other areas are able to generate an action potential at their own, slower rate, the SA node acts as the natural pacemaker of the heart. Nerve impulses from the autonomic nervous system (ANS) and blood-borne hormones (such as epinephrine) modify the timing and strength of each heartbeat, but they do not establish the fundamental rhythm." | |
| }, | |
| { | |
| "slide_number": 25, | |
| "slide_title": "SA node action potential", | |
| "chunk_id": "slide25_chunk0", | |
| "text": "SA node action potential" | |
| }, | |
| { | |
| "slide_number": 26, | |
| "slide_title": "Action potential and contraction of contractile fibers", | |
| "chunk_id": "slide26_chunk0", | |
| "text": "Action potential and contraction of contractile fibers" | |
| }, | |
| { | |
| "slide_number": 27, | |
| "slide_title": "ECG", | |
| "chunk_id": "slide27_chunk0", | |
| "text": "ECG Electrocardiogram Electrocardiograph Enlargements: Large P wave- arterial enlargement Enlarged Q wave- myocardial infraction Enlarged R wave- enlarged ventricles Flatten T wave- insufficient oxygen Lengthen P-Q – coronary artery disease" | |
| }, | |
| { | |
| "slide_number": 28, | |
| "slide_title": "ECG", | |
| "chunk_id": "slide28_chunk0", | |
| "text": "ECG By comparing ECG with one another and with normal records, it is possible to determine (1) if the conducting pathway is abnormal, (2) if the heart is enlarged, (3) if certain regions of the heart are damaged, and (4) the cause of chest pain Size wise information: 1) Larger P waves indicate enlargement of an atrium; 2) an enlarged Q wave may indicate a myocardial infarction; and 3) An enlarged R wave generally indicates enlarged ventricles. 4) The T wave is flatter than normal when the heart muscle is receiving insufficient oxygen—as, for example, in coronary artery disease. 5) The T wave may be elevated in hyperkalemia (high blood K level). Interval and segments: 1) the P–Q interval lengthens- coronary artery disease and rheumatic fever. 2) The S–T segment is elevated (above the" | |
| }, | |
| { | |
| "slide_number": 28, | |
| "slide_title": "ECG", | |
| "chunk_id": "slide28_chunk1", | |
| "text": "wave may be elevated in hyperkalemia (high blood K level). Interval and segments: 1) the P–Q interval lengthens- coronary artery disease and rheumatic fever. 2) The S–T segment is elevated (above the baseline) in acute myocardial infarction and depressed (below the baseline) when the heart muscle receives insufficient oxygen." | |
| }, | |
| { | |
| "slide_number": 31, | |
| "slide_title": "Cardiac cycle", | |
| "chunk_id": "slide31_chunk0", | |
| "text": "Cardiac cycle Cardiac Cycle" | |
| }, | |
| { | |
| "slide_number": 33, | |
| "slide_title": "Heart sounds", | |
| "chunk_id": "slide33_chunk0", | |
| "text": "Heart sounds S1- closure of AV valves S2-closure of SL valves Third sound- rushing of blood during ventricular filling Fourth sound- contraction of atrial muscles" | |
| }, | |
| { | |
| "slide_number": 34, | |
| "slide_title": "Cardiac output", | |
| "chunk_id": "slide34_chunk0", | |
| "text": "Cardiac output Volume of blood ejected from the left ventricle into the aorta each minute. CO=SV(70mL/beat) x HR(75 beats/min)=5,250mL/min Cardiac reserve: is the difference between a person’s maximum cardiac output and cardiac output at rest. End diastolic volume End systolic volume Ejection fraction: fraction of EDV that is ejected out by each ventricles. It is 54%, 70mL of 130mL (EDV). EDV-SV=ESV Regulation of stroke volume: 3 factors regulate the SV and ensure that the left and right ventricles pump equal volume of blood. a) Preload b)Contractility c)Afterload" | |
| }, | |
| { | |
| "slide_number": 35, | |
| "slide_title": "Volume changes in each heart beat per ventricle", | |
| "chunk_id": "slide35_chunk0", | |
| "text": "Volume changes in each heart beat per ventricle Remember both ventricles eject same amount of blood even though pressure in right ventricle is 25mmHg and on left side 120mmHg. It is required to maintain homeostasis. If right ventricle pumps more blood into the lungs than left – blood accumulates in lungs, causing pulmonary hypertension, edema, and a risk of drowning in one’s own body fluid. If left ventricle pumps more blood- blood accumulate in systemic circulation, causing hypertension and systemic edema (dropsy). In principle, if the output of the left ventricle were just 1% greater than output of the right, it would completely drain the lungs of blood in less than 10 minutes (although death would occur much sooner). Fluid accumulation in either circuit due to insufficiency of" | |
| }, | |
| { | |
| "slide_number": 35, | |
| "slide_title": "Volume changes in each heart beat per ventricle", | |
| "chunk_id": "slide35_chunk1", | |
| "text": "er than output of the right, it would completely drain the lungs of blood in less than 10 minutes (although death would occur much sooner). Fluid accumulation in either circuit due to insufficiency of ventricular pumping is called congestive heart failure." | |
| }, | |
| { | |
| "slide_number": 36, | |
| "slide_title": "Factors affecting cardiac output", | |
| "chunk_id": "slide36_chunk0", | |
| "text": "Factors affecting cardiac output" | |
| }, | |
| { | |
| "slide_number": 37, | |
| "slide_title": "Physiological variations in cardiac output", | |
| "chunk_id": "slide37_chunk0", | |
| "text": "Physiological variations in cardiac output Age Gender Body Build Diurnal Variations Environment temperature Emotional condition After meals Exercise High altitudes Posture Sleep pregrnancy" | |
| }, | |
| { | |
| "slide_number": 38, | |
| "slide_title": "Pathological variations", | |
| "chunk_id": "slide38_chunk0", | |
| "text": "Pathological variations Increase in cardiac output Fever Anemia Hyperthyroidism Decrease in cardiac output Hypothyroidism Atrial fibrillation Incomplete heart block Congestive heart failure" | |
| }, | |
| { | |
| "slide_number": 39, | |
| "slide_title": "Factors maintaining cardiac output", | |
| "chunk_id": "slide39_chunk0", | |
| "text": "Factors maintaining cardiac output Venous return Heart rate Peripheral resistance Force of contraction" | |
| }, | |
| { | |
| "slide_number": 40, | |
| "slide_title": "Regulation of SV", | |
| "chunk_id": "slide40_chunk0", | |
| "text": "Regulation of SV Preload(effect of stretching) the degree of stretch on the heart before it contracts (more diastole more contraction) SV proportional EDV Afterload(pressure that must be overcome before a semilunar valve can open. An increase in afterload causes stroke volume to decrease. Contractility the forcefulness of contraction of individual ventricular muscle fibers at any given preload. Ca++ inotropic positive agent. Preload Ventricular filling (EDV) Duration of Venous ventricular diastole return" | |
| }, | |
| { | |
| "slide_number": 42, | |
| "slide_title": "Heart Rate", | |
| "chunk_id": "slide42_chunk0", | |
| "text": "Heart Rate Normal range: 60 to 80 beats Tachycardia : above 100 beats per minute Bradycardia : below 60 beats per minutes Regulation of heart rate Vasomotor center Motor nerve fibers Sensory nerve fibers" | |
| }, | |
| { | |
| "slide_number": 43, | |
| "slide_title": "Regulation of heart rate", | |
| "chunk_id": "slide43_chunk0", | |
| "text": "Regulation of heart rate" | |
| }, | |
| { | |
| "slide_number": 44, | |
| "slide_title": "Regulation of heart rate", | |
| "chunk_id": "slide44_chunk0", | |
| "text": "Regulation of heart rate" | |
| }, | |
| { | |
| "slide_number": 45, | |
| "slide_title": "Chemical regulation", | |
| "chunk_id": "slide45_chunk0", | |
| "text": "Chemical regulation" | |
| }, | |
| { | |
| "slide_number": 46, | |
| "slide_title": "Blood pressure", | |
| "chunk_id": "slide46_chunk0", | |
| "text": "Blood pressure The hydrostatic pressure exerted by blood on the walls of a blood vessel. It is determined by Cardiac output, blood volume and vascular resistance. MAP=DP+(1/3)(SP-DP) MAP=CO x R" | |
| }, | |
| { | |
| "slide_number": 47, | |
| "slide_title": "Vascular resistance", | |
| "chunk_id": "slide47_chunk0", | |
| "text": "Vascular resistance It is the opposition of blood flow due to friction between blood and walls of blood vessels. VR depends on : Size of blood vessel lumen (Rα 1/d4 ) Blood viscosity :depends mostly on ratio of RBC to plasma volume and concentration of protein. Total blood vessel length Systemic vascular resistance" | |
| }, | |
| { | |
| "slide_number": 49, | |
| "slide_title": "Regulation of blood pressure", | |
| "chunk_id": "slide49_chunk0", | |
| "text": "Regulation of blood pressure Nervous system Renal mechanism Hormonal mechanism Local mechanism Vasomotor center Vasoconstrictor fibre Vasomotor tone" | |
| }, | |
| { | |
| "slide_number": 52, | |
| "slide_title": "Hormonal mechanism", | |
| "chunk_id": "slide52_chunk0", | |
| "text": "Hormonal mechanism Adrenaline : it increases SP by increasing the force of contraction and decreases DP by decreasing peripheral resistance. Noradrenaline: vasoconstrictor Thyroxin: Increase SP and decrease DP Aldosterone: retention of sodium and water Prostaglandins : vasodilator" | |
| } | |
| ] |