Which medication class is used for chest pain relief in ACS provided blood pressure is adequate?

• A. Beta-blockers
• B. Nitrates
• C. Morphine
• D. ACE inhibitors

Answer: (B)

Nitrates are used for chest pain relief in ACS when blood pressure is adequate because they rapidly reduce myocardial oxygen demand while potentially increasing oxygen supply. They achieve this mainly through venodilation, which lowers preload and wall stress, decreasing the heart’s oxygen requirements. They also provide some coronary vasodilation, which can help improve blood flow to ischemic areas. Because nitrates can cause a drop in blood pressure, they’re given only if the patient is hemodynamically stable with a sufficient systolic BP. Sublingual nitroglycerin acts quickly and can be repeated if pain persists, with IV nitroglycerin available for ongoing relief under careful monitoring. If blood pressure isn’t adequate, nitrates are withheld and alternative pain relief strategies are used. Other drug classes have important roles in ACS but are not the immediate chest pain-relief choice when BP is sufficient: beta-blockers help reduce oxygen demand but aren’t the first-line analgesic; morphine provides analgesia but has systemic effects and is not the primary option for pain relief; ACE inhibitors are mainly for afterload reduction and remodeling prevention after stabilization.