What role does nitroglycerin (NTG) play in Coronary Artery Disease (CAD)?

Nitroglycerin plays a critical role in the management of Coronary Artery Disease (CAD) by dilating blood vessels. This vasodilation is primarily beneficial because it decreases the workload on the heart and improves blood flow to the myocardium (heart muscle), particularly in areas that may be compromised due to narrowed or blocked arteries.

By expanding both arteries and veins, nitroglycerin reduces the amount of blood returning to the heart (preload) and the resistance the heart must work against to pump blood (afterload). This results in lower oxygen demand by the heart while simultaneously enhancing oxygen delivery to the tissues. This mechanism is particularly useful during episodes of angina, where pain results from reduced blood flow and oxygen delivery to the heart.

In contrast, options suggesting that nitroglycerin increases heart rate, reduces blood volume, or strengthens heart contractions do not accurately reflect the pharmacological effects of nitroglycerin. Thus, the correct understanding of its role in CAD relates directly to its vasodilatory properties.