How does nitroglycerin assist the heart?

Nitroglycerin assists the heart primarily by dilating the coronary arteries. It is a vasodilator, which means it relaxes and expands blood vessels. When nitroglycerin is administered, it helps to alleviate chest pain (angina) by increasing blood flow to the heart muscle. This is crucial because the heart requires a sufficient supply of oxygen-rich blood to function effectively, and any increase in blood flow can help to relieve ischemic conditions.

By dilating the coronary arteries, nitroglycerin reduces the workload of the heart and lowers the oxygen demand. This mechanism is especially beneficial during episodes of angina, as it directly addresses the reduced blood supply to the heart muscle. This contrasts with choices that suggest increasing heart rate or decreasing blood flow, which would not be supportive mechanisms in the context of managing heart conditions.