HLSC 3P90 Lecture Notes - Lecture 1: Endoplasmic Reticulum, Myosin Head, Calcium Atpase
Document Summary
Amount of blood pumped by each ventricle per minute (l/min: represents the blood flow for the entire cardiovascular system, reflects the heart"s ability to meet the body"s need for blood flow. Q (l/min) = hr (bpm) x sv (ml) Factors affecting the heart rate do so by changing the depolarization and repolarization of pacemaker cells. This is controlled by the autonomic nervous system: sympathetic (sns, parasympathetic (pns) Amounts of blood ejected from the ventricle per beat. 3 important factors that affect the sv: preload, afterload, contractility. Amount of blood returned to the heart in diastole. Frank-starling law an increased stretch in myocardium enhances contractile force of myocardium, causing more blood to be ejected. Provides an intrinsic mechanism to balance output form left and right ventricles. Amount of blood in ventricle is determined by: venous return, ventricular filling-time (heart rate) Sv = end diastolic volume end systolic volume: sv = (edv esv) Frank-starling mechanism matched out venous return with cardiac output.