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Cardiology 2

Cardiology II: In this lecture, Professor Diamond continues her conversation on the heart, reviewing its chambers and discussing heart valves, heart sounds, cardiac cycle, pathways of the blood through the heart, conduction mechanism, and nerve supply. She first describes distinguishing characteristics of the ventricles, such as the thicker walls of the left ventricle. She also details the atrioventricular (AV) and semilunar (SL) valves that control blood flow within the heart and touches on valve disorders and challenges with current valve replacement technologies. Professor Diamond then relates sounds of the heart to valves, noting that the stronger lub sound is caused by the AV valves and the dub sound by the SL valves. She describes how the valves open and close alternately during the cardiac cycle and discusses how blood flows from the vena cava into the heart, through the lungs, back to the heart, and into the aorta. Professor Diamond next details the conduction mechanism for the heart. She concludes by reviewing the autonomic nervous system and its sympathetic and parasympathetic components, and discussing how these control the nodes that determine the heart’s pace.