CARDIOVASCULAR CARDIOVASCULAR SYSTEMSYSTEM
THE HEARTChapter 18
Physical CharacteristicsPhysical Characteristics
Located in the mediastinum between the lungs and behind the sternum
About the size of a clenched fist
Shaped like an inverted cone
Apex vs. Base
Coverings and LayersCoverings and Layers Covering Around the Heart
– Pericardium Fibrous pericardium Serous pericardium
– Parietal layer
– Visceral layer (epicardium)
– Serous fluid
Walls of the Heart– Epicardium– Myocardium– Endocardium
ChambersChambers
Atria– Right atrium– Left atrium– Interatrial septum– Fossa ovalis
Ventricles– Right ventricle– Left ventricle– Interventricular septum
Differences between the Differences between the VentriclesVentricles
ValvesValves Atrioventricular valves
– Tricuspid– Bicuspid (mitral)
Semilunar valves– Pulmonary semilunar– Aortic semilunar
Associated Structures– Chordae tendineae– Papillary muscles
ValvesValves
AV ValvesAV Valves
Semilunar ValvesSemilunar Valves
Heart Valve VideoHeart Valve Video
Microscopic AnatomyMicroscopic Anatomy
Microscopic AnatomyMicroscopic Anatomy
Blood FlowBlood Flow
Pulmonary CircuitSystemic CircuitCoronary CircuitVenous Drainage
Blood Flow Animation
Pulmonary vs. SystemicPulmonary vs. Systemic
Pulmonary CirculationPulmonary Circulation
Superior and inferior vena cava and coronary sinus
Right atrium Tricuspid Right Ventricle Pulmonary semilunar Pulmonary arteries Lungs
Systemic CirculationSystemic Circulation
Pulmonary veins Left atrium Bicuspid valve Left ventricle Aortic semilunar Systemic aorta Coronary artery
Coronary CirculationCoronary Circulation Left coronary artery
– Anterior interventricular artery
– Circumflex artery
Right coronary artery– Posterior
interventricular artery– Marginal artery
Arterial anatomoses
Posterior ViewPosterior View
Venous DrainageVenous Drainage
Superior vena cava Inferior vena cava Great cardiac vein Small cardiac vein Middle cardiac vein Coronary sinus
Posterior ViewPosterior View
Posterior ViewPosterior View
Anastomoses of Coronary Anastomoses of Coronary CirculationCirculation
Cardiac Conduction SystemsCardiac Conduction Systems
Intrinsic Cardiac Intrinsic Cardiac Conduction System AnimationConduction System Animation
Extrinsic Cardiac Extrinsic Cardiac Conduction SystemConduction System
Autonomic Innervation– Sympathetic nervous
system– Parasympathetic nervous
system
Cardiac PhysiologyCardiac Physiology
EKG
Heart Sounds
Cardiac Cycle
ElectrocardiographElectrocardiograph
EKG and ConductionEKG and Conduction
EKG AnimationEKG Animation
Abnormal ECGAbnormal ECG
Heart SoundsHeart Sounds
Auscultate Stethoscope Lub-dup, pause, lub-dup,
pause, etc Lub= AV valves closing Dup=Semilunar valves
closing
Cardiac Cycle AnimationCardiac Cycle Animation
Cardiac OutputCardiac Output
Cardiac output (CO) = the amount of blood pumped by each ventricle per minute
– CO = SV X HR– SV=“stroke volume” or the amount of blood
pumped by a ventricle in a single beat– HR=“heart rate” or number of beats per minute
Factors Affecting SVFactors Affecting SV
Factors Affecting SVFactors Affecting SV
ContractilityContractilityPositive Inotropic Agents
- Sympathetic NS
- Digitalis
- Glucagon (pancreas)
- Epinephrine
- Hypercalcemia
Negative Inotropic Agents- Hyperkalemia
- Hypocalcemia
- Cardiac hypoxia
- Cardiac hypercapnia
Factors Affecting HRFactors Affecting HR
Autonomic nervous systemHormones: epinephrine and thyroxineAge, gender, fitness, emotional stateBody temperatureIon concentrations in body fluidsBlood pressure
HomeostasisHomeostasis
Cardiac DisordersCardiac Disorders Valve disorders
– Heart murmur Stenosis Incompetent valve Mitral valve prolapse
– Rheumatic fever or Streptococcus infection– Sclerosis and thickening of valve flaps
Arrhythmias– Tachycardia– Bradycardia– Fibrillation– Heart block
Cardiac DisordersCardiac Disorders Other related heart problems
– Ischemia and hypoxia– Angina pectoralis – Myocardial infarction– Heart palpitation– Asystole– Myocarditis– Endocarditis– Cardiac tamponade– Pericarditis– Congenital defects– Congestive heart failure