heart
Page 1: The Cardiovascular System: The Heart Anatomy
Page 2: Heart Anatomy
Size: Approximately the size of a fist
Location:
Superior surface of the diaphragm
Left of the midline
Anterior to the vertebral column, posterior to the sternum
Page 3: Heart Anatomy Midsternal Line
Key anatomical landmarks include:
2nd rib, sternum, diaphragm
Point of maximal intensity: Left lung (PMI)
Major vessels:
Aorta (a)
Parietal pleura (cut)
Pulmonary trunk
Right and left lungs
Parietal pericardium (b, anterior cut)
Apex of the heart
(c) diaphragm
Page 4: Coverings of the Heart: Anatomy
Pericardium: A double-walled sac surrounding the heart
Superficial fibrous pericardium
Deep two-layer serous pericardium:
Parietal layer (lines internal surface of fibrous pericardium)
Visceral layer (epicardium, lines surface of heart)
Pericardial cavity: Fluid-filled space between layers
Page 5: Coverings of the Heart: Physiology
Function of the Pericardium:
Protects and anchors the heart
Prevents overfilling with blood
Provides a friction-free environment for heart movement
Page 6: Pericardial Layers of the Heart
Fibrous pericardium
Parietal layer of serous pericardium
Myocardium
Pericardial cavity
Visceral layer of serous pericardium (epicardium)
Endocardium
Page 7: Heart Wall
Epicardium: Visceral layer of serous pericardium
Myocardium: Cardiac muscle layer that forms heart's bulk
Fibrous skeleton: Connective tissue framework
Endocardium: Inner layer of heart's surface
Page 8: Major Blood Vessels Returning Blood to the Heart
Superior and inferior venae cavae
Right and left pulmonary veins
Vessels conveying blood away:
Pulmonary trunk (splits into right and left pulmonary arteries)
Ascending aorta and its branches
Brachiocephalic, left common carotid, subclavian arteries
Page 9: External Heart: Major Vessels (Anterior View)
Coronary arteries (right and left in atrioventricular groove)
Marginal, circumflex, anterior interventricular arteries
Cardiac veins include small, anterior, and great cardiac veins
Page 10: External Heart: Anterior View
Key structures:
Brachiocephalic artery, left common carotid, left subclavian artery, aortic arch
Ascending aorta, left pulmonary artery and veins, circumflex artery, etc.
Page 11: Major Vessels of the Heart (Posterior View)
Vessels returning blood:
Right and left pulmonary veins, superior and inferior venae cavae
Vessels conveying blood away:
Aorta, right and left pulmonary arteries
Page 12: Posterior View of Heart Vessels
Right coronary artery, posterior interventricular artery
Major cardiac veins: great cardiac vein, coronary sinus
Page 13: External Heart: Posterior View
Key components:
Aorta, left and right pulmonary arteries, auricles of the atria, etc.
Page 14: Gross Anatomy of Heart: Frontal Section
Structures including aorta, pulmonary veins, mitral (bicuspid) valve, tricuspid valve, etc.
Page 15: Atria of the Heart
Atria serve as receiving chambers
Each atrium features a protruding auricle
Blood flow: right atrium (superior/inferior venae cavae, coronary sinus); left atrium (pulmonary veins)
Page 16: Ventricles of the Heart
Ventricles as discharging chambers
Structures: papillary muscles, trabeculae carneae
Blood flow: right ventricle (to pulmonary trunk); left ventricle (to aorta)
Page 17: Myocardial Thickness and Function
Varies by chamber function:
Thin-walled atria deliver blood to ventricles
Thicker-walled ventricles: right for pulmonary circulation, left for systemic
Page 18: Thickness of Cardiac Walls
Left ventricle is thicker than the right ventricle
Page 19: Atrial Septal Defect
A defect affecting inter-atrial septum
Page 20: Ventricular Septal Defect
A defect in the ventricular septum
Page 21: Pathway of Blood Through the Heart and Lungs
Sequence:
Right atrium -> tricuspid valve -> right ventricle
Right ventricle -> pulmonary semilunar valve -> pulmonary arteries -> lungs
Lungs -> pulmonary veins -> left atrium
Left atrium -> bicuspid valve -> left ventricle
Left ventricle -> aortic semilunar valve -> aorta -> systemic circulation
Page 22: Pathway of Blood Through the Heart and Lungs
Involves pulmonary circuit (gas exchange occurs in capillary beds of lungs)
Oxygen-rich from lungs to left atrium; oxygen-poor from tissues back to right atrium
Page 23: Coronary Circulation
Functional blood supply to the heart muscle
Collateral routes for blood delivery to the heart muscle
Page 24: Coronary Circulation: Arterial Supply
Major arteries: left and right coronary arteries
Anastomosis connects coronary vessels
Page 25: Coronary Circulation: Venous Supply
Superior vena cava, great cardiac vein, coronary sinus, small cardiac vein
Page 26: Heart Valves
Ensure unidirectional blood flow
Atrioventricular valves: between atria and ventricles, prevent backflow into atria
Anchored by chordae tendineae
Page 27: Heart Valves
Semilunar valves: prevent backflow into ventricles
Aortic semilunar valve: between left ventricle and aorta
Pulmonary semilunar valve: between right ventricle and pulmonary trunk
Page 28: Heart Valves Structure
Includes bicuspid (mitral), tricuspid, aortic semilunar, and pulmonary semilunar valves
Page 29: Heart Valves Function
Atrioventricular valve function explained
Allows filling and prevents backflow associated with ventricular contraction
Page 30: Atrioventricular Valve Function
Sequence during atrial and ventricular contraction
Involvement of chordae tendineae and papillary muscles in preventing valve eversion
Page 31: Semilunar Valve Function
Function during ventricular contraction and relaxation explained
Page 32: Mitral Valve Prolapse
One leaflet of the mitral valve fails to close properly
Page 33: Microscopic Anatomy of Heart Muscle
Properties of cardiac muscle: striated, short, branched
Importance of intercalated discs for connection and electrical impulse transmission between cardiac cells
Page 34: Microscopic Anatomy of Heart Muscle
Diagram illustrating cellular structure, including intercalated discs and mitochondria
Page 35: Cardiovascular System: The Heart Physiology
Page 36: Cardiac Muscle Contraction
Heart muscle is stimulated by nerves and is self-excitable
Contracts as a unit, with a long refractory period
Similar contraction mechanism to skeletal muscle
Page 37: Heart Physiology: Intrinsic Conduction System
Role of autorhythmic cells in generating action potentials
Importance of calcium influx for action potential phase
Page 38: Pacemaker and Action Potentials of the Heart
Detailed overview of the pacemaker potential graph, including ion movements
Page 39: Heart Physiology: Sequence of Excitation
SA node initiates impulses at approximately 75 beats/min
AV node delays impulse for coordination
Page 40: Heart Physiology: Sequence of Excitation
Impulse travels from atria to ventricles via AV bundle, splits into bundle branches
Purkinje fibers carry impulses to ventricular walls
Page 41: Heart Physiology: Sequence of Excitation
Overview of the conduction pathway through the heart, beginning with SA node
Page 42: Heart Excitation Related to ECG
Relations between SA node generation and ECG patterns explained
Page 43: Extrinsic Innervation of the Heart
Autonomic regulation: sympathetic (accelerating) and parasympathetic (inhibiting)-
Page 44: Electrocardiography
Recording of electrical activity with key waveforms: P wave, QRS complex, T wave
Page 45: Electrocardiography
Insights into the timing of electrical signals and heart valve closures through the ECG diagram
Page 46: Heart Sounds
Sounds correspond to heart valve closures:
"Lub" sound (AV valves close) marks ventricular systole
"Dup" sound (SL valves close) signifies ventricular diastole
Page 47: Cardiac Cycle
Definition and components of the cardiac cycle explained
Systole: contraction phase
Diastole: relaxation phase
Page 48: Phases of the Cardiac Cycle
Description of ventricular filling and initial atrial events
Page 49: Phases of the Cardiac Cycle
Description of ventricular systole, internal pressure changes and valve actions
Page 50: Phases of the Cardiac Cycle
Event sequence of isovolumetric relaxation explained
Page 51: Phases of the Cardiac Cycle
Detailed overview of each phase of the cardiac cycle demonstrated via a chart
Page 52: Cardiac Output (CO) and Reserve
Definition of CO: blood volume ejected by each ventricle per minute
Calculated as product of heart rate (HR) and stroke volume (SV)
Page 53: Cardiac Output: Example
Example calculation: CO = HR (75 BPM) x SV (70 ml/beat) = 5250 ml/min (5.25 L/min)
Page 54: Regulation of Stroke Volume
Relationship: Stroke Volume = End Diastolic Volume (EDV) - End Systolic Volume (ESV)
Page 55: Factors Affecting Stroke Volume
Key factors: preload, contractility, afterload
Page 56: Frank-Starling Law of the Heart
Preload determines stroke volume based on stretch dynamics
Page 57: Preload and Afterload
Diagram illustrating the concepts of preload and afterload in relation to cardiac output
Page 58: Extrinsic Factors Influencing Stroke Volume
Factors that positively influence contractility outlined
Page 59: Extrinsic Factors Influencing Stroke Volume
Factors that negatively influence contractility outlined
Page 60: Contractility and Norepinephrine
Mechanism of sympathetic stimulation concerning cardiac contractility explained
Page 61: Regulation of Heart Rate
Factors that influence heart rate, including caffeine (positive) and sedatives (negative)
Page 62: Regulation of Heart Rate: Autonomic Nervous System
Distinction between effects of SNS (accelerating) and PNS (slowing)
Page 63: Atrial (Bainbridge) Reflex
Sympathetic reflex activated by increased blood volume in the atria
Page 64: Chemical Regulation of the Heart
Hormones and ion concentrations' effects on heart rate regulation described
Page 65: Factors Involved in Regulation of Cardiac Output
Overview of physiological responses to various stimuli affecting CO
Page 66: Congestive Heart Failure (CHF)
Causes include coronary atherosclerosis, high blood pressure, myocardial infarcts, DCM
Page 67: Developmental Aspects of the Heart
Fetal heart structures bypassing pulmonary circulation explained
Page 68: Examples of Congenital Heart Defects
Various congenital defects with accompanying explanations
Page 69: Age-Related Changes Affecting the Heart
Changes include valve sclerosis, cardiac reserve decline, cardiac muscle fibrosis
Page 70: Congestive Heart Failure
Detailed mechanisms causing left and right heart failure described
Page 71: Coronary Artery Disease
Insufficient blood supply to heart muscle due to narrowed vessels, with treatment options
Page 72: Clinical Problems
Overview of conditions such as myocardial infarction, angina pectoris, and treatments
Page 73: By-pass Graft
Surgery process of grafting a vessel to bypass an obstruction
Page 74: Percutaneous Transluminal Coronary Angioplasty
Procedure elaborated: uses a balloon catheter to widen narrowed arteries.
Page 75: Artificial Heart
Information regarding advancements and function of artificial hearts.