NURS 3550H Lecture Notes - Lecture 3: Vascular Smooth Muscle, Atrioventricular Node, Coronary Circulation
28 Dec 2018
School
Department
Course
Professor
Document Summary
Mechanism: works at the channel, blocks calcium channel by binding to the receptor on the channel, can work at the heart and/or vascular smooth muscle. Two families of ccbs: verpamil, diltiazem, works at both the heart and vsm, dihydropyridines, works at vsm only, can work at heart at very toxic dosages, prototype drug: nifedipine. Verapamil effects: at the arteries and arterioles, causes vasodilation. Increases coronary perfusion: at the heart, sa node decreases in hr, av node decrease in conduction, muscle decrease in contractility. Verapamil indications: htn, due to vasodilation, decrease in hr, angina. Increase oxygen delivery to the heart through increasing perfusion of the coronary arteries: decrease oxygen demand by decreasing hr, conduction, and muscle contractility. Decreases workload on heart: cardiac dysrhythmias, tardive dyskinesia, migraines, due to vasodilation. Verapamil drug interactions: b-blockers, additive effects, b-receptors open calcium channels, digoxin, digoxin is used to treat a failing heart, slows conductance through av node and clearance, grapefruit juice.
