BMS 460 Lecture Notes - Cytoskeleton, Sarcomere, Childbirth
Document Summary
Ischemic heart disease: imbalance between myocardial oxygen supply and demand hypoxia and metabolic build-up. Major symptom is angina pectoris or strangling in the heart . Unstable angina preinfarctional, active clots on vulnerable plaque. Silent angina diabetes, not very painful due to subdued nerve endings. Perfusion pressure: predominance of flow during diastole vs. systole. External compression during systole: subendocardium most prone to ischemia. Intrinsic tone via autoregulation: local metabolites, mediators of tone from. Mismatching occurs between supply and demand in coronary artery disease when poor perfusion (plaque, platelet aggregation, vasospasm) occurs or vascular tone doesn"t decrease (dysfunctional endothelium) to meet demands. Sns enhanced venoconstriction and hr and co. Raas enhanced fluid retention hr and co. Result: sv and co but this increases workload of compromised heart as afterload, heart rate and contractility increase. 6 month mortality rate of 25% and if untreated death. Bacteria rheumatic valve disease, congenital bicuspid aortic valve, normal aortic valve (virulent bacteria) endocarditis.