PNB 2265 Lecture Notes - Lecture 6: Heart Murmur, Coronary Artery Disease, Ductus Arteriosus

• School: UConn
• Department: Physiology and Neurobiology
• Course: PNB 2265
• Professor: Kristen Kimball

Document Summary

Must have pressure in order to flow. Valve = can only flow one direction. Pumping supplies the pressure to move through a set of capillaries. The average heart is the size of a fist. Contracts about 2. 5 billion times in an average (human) lifetime. Pathological accumulation of fluid in pericardial cavity. Fluid building up may be caused by infection, trauma. Places pressure and strain on the heart muscle (decrease stroke volume) Myocardium = cardiac muscle (thickest, where myocytes are, contracting) Atrioventricular valves are attached to chordae tendinae. Chordae tendinae attach the av valves to papillary muscles. Stabilize valves, not open and close (pressure gradient opens and closes) Av valves open when ventricles are relaxed. Sl valves open when ventricles are contracted. Each atria and each ventricle pass through systolic (contraction) and diastolic (relaxation) phases in unison. Av and semilunar valves must open and close to accommodate these phases. Foramen ovale - blood can move from right to left atrium directly.