Cardiac Physiology

Components of the CV system 7 A arteries deliver blood from heart to the tissue B capillaries exchange occurs C veins to the circulation circulation is in the The central pump heart and the generic Valves term of the 4 chambered arterial systole heart systemic A B vena heart delivery Semilunar and the to Atrioventricular ventricles I and systole separate great vessels valves separat atria Tricuspid right II Mi trial aorta circulation valves from v en ou cava refers to a ventricular ventricle semilunar pump arteries artery pulmonary central is in the veins and is composed of the to the heart return blood return D heart Pulmonary where Av valve left Av valve valves open during systole and open during diastole atri ventricular valves Spontaneous depolarization at the sinai node SA node is what causes the heart to begin Steps of ventricular left Congestion a ventricles of lower pressure a and AV node t delay contraction contract in unison up of blood due to a blockage back Blood flows from the contraction and depolarization right and atrial SA node depolarization contraction depolarization contraction region of higher pressure to down the pressure gradient highest pressure in the heart is the a regio pulmonary artery and the next highest is the left ventricle BP measurements Systemic circulation During systole systolic diastolic is higher pressure than pulmonary ventricular BP great vessel pressure ventricular BPL great vessel pressure During diastole t blood flow is directly related to pressure difference inversely related to vascular resistance The SA node depolarizes spontaneously resting membrane an because it has n potential movement of cast causes spontaneous depolarization The AV node allows for sequential atrioventricular The more gap junctions are present the faster a will travel contract i signal purkinje fibers AV node is slowest are fastest Specialized myocytes are working myocytes responsible for contraction are Plateau in the action allows responsible potential of for sustained a for excitation and working myocyte contraction ECG wave s atrial depolarization ventricular repolarization A if 1 PR I o 1 QT Heart sounds 51 flub is semilunar dub is semilunar and 54 is atrial Murmurs ventricular depolarization valves valves opening 52 closing 53 is ventricular filling contraction represent turbulent blood flow Erdacyce electrical and mechanical with each heart beat one systole events that occur diastole the cardiac cycle is inversely related to heart rate 4 phases of the cardiac cycle I filling diastole II Iso volumetric contraction during iso volumetric III ejection systole stages all valves are closed II i so volumetric Electrical activity precedes mechanical relaxation activity Heart sounds mark the beginning and end of systole Preload is the tension in the walls at the end of diastole t increased preload increased filling associated After load is the tension in the walls during ejection to how much heart contracts Contractility is how much a w exercise related decreases stroke volume heart will contract