What are the effects of nitrates on the cardiac preload, afterload, and MVO2?
Nitrates are endothelium-independent vasodilators with peripheral and coronary vascular effects. By dilating the capacitance vessels, nitrates decrease cardiac preload and reduce ventricular wall tension. More modest effects on the arterial circulation result in afterload reduction and further decrease in MVO2. This may be partially offset by reflex increases in heart rate and contractility, which counteract the reduction in MVO2 unless a beta blocker is concurrently administered.