Which of the following is a contraindication to nitroglycerin administration in chest pain?

• A. Suspected RV infarct
• B. SBP 115 mmHg
• C. History of migraines
• D. Recent meal

Answer: (A)

Nitroglycerin lowers preload by dilating veins, which reduces the amount of blood returning to the heart. In a right ventricular infarct, the right ventricle relies on adequate preload to maintain cardiac output. Pushing more venodilation here can drop preload further and cause a dangerous fall in output and blood pressure. That’s why suspected right ventricular infarct is a contraindication to nitroglycerin.

A systolic BP of 115 mmHg isn’t by itself a reason to withhold nitro, as long as the patient remains hemodynamically stable and there are no other contraindications. A history of migraines and a recent meal don’t contraindicate nitroglycerin in this context; they’re not reasons to avoid the drug. If RV infarct is suspected, the focus is on avoiding preload reduction and often supporting preload with fluids while closely monitoring.