"The Pain Was Relieved by Nitro": Helpful Information?

Relief with nitroglycerin is thought by some to be characteristic of anginal chest pain. What is the prognostic value of this clinical observation? Researchers in Maryland prospectively studied 459 patients who received nitroglycerin (0.4 mg) after they presented with chest pain to an emergency department.

Symptom relief was defined as ≥50% decrease in self-reported chest pain within 5 minutes of receiving nitroglycerin. Active CAD was defined as ≥70% stenosis on cardiac catheterization; any serum troponin T elevation; a positive exercise-test result; or physician diagnosis of CAD, confirmed by a cardiologist who was blinded to nitroglycerin-relief status.

Active CAD was present in 141 patients (31%). Nitroglycerin relieved chest pain in 181 …