PHA 3112 Chapter Notes - Chapter 51: Coronary Vasospasm, Angina Pectoris, Calcium Channel Blocker

• School: University of Ottawa
• Department: Pharmacology
• Course: PHA 3112
• Professor: Pierre Fortier

Document Summary

Angina pectoris: sudden pain beneath sternum (chest bone), radiating to left shoulder & arm. Angina occurs when oxygen supply to heart is insufficient to meet oxygen demand. Angina is seen as symptom, not disease = often occurs secondary to atherosclerosis of coronary arterie. Determinants of cardiac oxygen demand and oxygen supply. Cardiac oxygen demand factors/principal determinants are: (drugs reduce oxygen demand & 3 factors: heart rate, myocardial contractility, , intramyocardial wall tension (most imp, determined by cardiac preload & cardiac afterload) Cardiac oxygen supply is determined by: myocardial blood flow (perfusion): only occurs during diastole (heart relaxes, not systole) Under resting conditions, heart extracts nearly all oxygen delivered by coronary vessels = only way to accumulate increase oxygen demand is to increase bf. Bf increase coronary arterioles dilate decrease vascular resistance allow bf to increase. Does(cid:374)"t o(cid:272)(cid:272)u(cid:396) du(cid:396)i(cid:374)g systole (cid:272)uz (cid:373)yo(cid:272)a(cid:396)diu(cid:373) supply (cid:448)essels a(cid:396)e s(cid:395)ueezed shut (cid:449)he(cid:374) hea(cid:396)t (cid:272)o(cid:374)t(cid:396)a(cid:272)ts.