Chest pain relief by nitroglycerin does not predict active coronary artery disease.

BACKGROUND: The belief that chest pain relief with nitroglycerin indicates the presence of active coronary artery disease is common. However, this hypothesis has not been tested. OBJECTIVE: To define the diagnostic and prognostic value of chest pain relief with nitroglycerin. DESIGN: Prospective observational cohort study. SETTING: Urban community teaching hospital. PATIENTS: 459 consecutive patients with chest pain admitted through the emergency department who received nitroglycerin from emergency services personnel or an emergency department nurse. Follow-up was obtained by telephone contact at 4 months. MEASUREMENTS: Chest pain relief was defined as a decrease of at least 50% in patients' self-reported pain within 5 minutes of the initial dose of sublingual or spray nitroglycerin. Active coronary artery disease was defined as any elevated serum enzyme levels, coronary angiography demonstrating a 70% or greater stenosis, or a positive exercise test result. RESULTS: Nitroglycerin relieved chest pain in 39% of patients (181 of 459). In patients with active coronary artery disease as the likely cause of their chest pain, 35% (49 of 141) had chest pain relief with nitroglycerin. In contrast, in patients without active coronary artery disease, 41% (113 of 275) had chest pain relief (P > 0.2). Four-month clinical outcomes were similar in patients with or without chest pain relief with nitroglycerin (P > 0.2). CONCLUSIONS: These data suggest that, in a general population admitted for chest pain, relief of pain after nitroglycerin treatment does not predict active coronary artery disease and should not be used to guide diagnosis.

Prognostic usefulness of marginal troponin T elevation.

Marginal elevations of troponin T among patients with chest pain are often considered to be insignificant. We sought to define the prognostic value of marginal troponin T elevations in patients presenting to the emergency department with suspected myocardial ischemia. Four hundred twenty-eight consecutive patients presenting to the emergency department with ongoing chest pain were evaluated, followed through their hospital course, and contacted for follow-up 4 months after discharge. Two hundred ninety-nine patients had undetectable troponin T levels (<0.01 microg/L), 76 had marginal troponin T elevations (0.01 to 0.09 microg/L), and 53 had frank troponin T elevations (> or =0.1 microg/L). Patients with either marginally or frank elevated troponin levels were older and more likely to be men, but did not differ from patients with undetectable troponin levels with regard to the prevalence of coronary artery disease risk factors, history of coronary disease, or race. While in the hospital, the undetectable and marginal troponin groups were referred for cardiac testing in equal proportions (58% and 59%, respectively), whereas 87% of the elevated group underwent further testing. After adjustment for possible confounders, a significantly increased rate of death/myocardial infarction/revascularization was observed in the marginal troponin group compared with the undetectable troponin group (p = 0.004). Marginal elevations of troponin T identified a currently underevaluated high-risk subgroup of patients with suspected myocardial ischemia who are more likely to have adverse clinical outcomes than those with undetectable troponin levels.