Physiology 3120 Lecture Notes - Lecture 4: Aortic Valve, Heart Valve, Cardiac Output

• School: Western University
• Department: Physiology
• Course: Physiology 3120
• Professor: Tom Stavraky

Document Summary

Mechanical performance of the heart cardiac output. It shows all the mechanical and electrical events during a single contraction. Includes: pressure changes in aorta, left atrium and left ventricle, volume changes in left ventricle, ecg, phonocardiogram. Consists of a period of ventricular: diastole lasting 0. 53s (relaxation event of heart, systole lasting 0. 27s (contraction event of heart) There are 7 phases: atrial systole, isovolumetric (ventricular) contraction, (rapid) ejection period, protodiastole, isovolumetric (ventricular) relaxation, rapid inflow, diastasis (1) atrial systole, p wave atria contract, p-wave: represents the depolarization of atria, contraction increases atrial pressure. Ventricular pressure (av valves are already open) (cid:498)last(cid:499) 30% of ventricular filling end diastolic. Volume (edv: edv: volume of blood in the ventricles after diastole (2) isovolumetric (ventricular) contraction. Qrs complex ventricles begin contracting: qrs complex: represents depolarization of ventricles, contract from bottom up, pressure builds up. Ventricular p > atrial p (av valves close: 1st heart sound.