Chest Pain in Emergency Department Patients: If the Pain is Relieved by Nitroglycerin, is it More Likely to be Cardiac Chest Pain?

Abstract

It is often believed that chest pain relieved by nitroglycerin is indicative of coronary artery disease origin. To determine if relief of chest pain with nitroglycerin can be used as a diagnostic test to help differentiate cardiac chest pain and non-cardiac chest pain. Prospective observational cohort study with a 4-week follow-up of patients enrolled. Academic tertiary care hospital, with 60,000 visits/year. Adult patients presenting to the emergency department with active chest pain who received nitroglycerin and were admitted for chest pain. Patients with acute myocardial infarction diagnosed after obtaining an ECG, patients whose chest pain could not be quantified, those for whom no cardiac work-up was done, or those who received emergent cardiac catheterization. 270 patients were enrolled. Nitroglycerin relieved chest pain in 66% of the subjects. The diagnostic sensitivity of nitroglycerin to determine cardiac chest pain was 72% (64%-80%), and the specificity was 37% (34%-41%). The positive likelihood ratio for having coronary artery disease if nitroglycerin relieved chest pain was 1.1 (0.96-1.34). Telephone follow-up at 4 weeks was performed, with a 95% follow-up rate. Relief of chest pain with nitroglycerin is not a reliable diagnostic test and does not distinguish between cardiac and non-cardiac chest pain.