Ankle-Brachial Index in Addition to Stress Testing in Patients Who Presented With Chest Pain and 1-Year Major Cardiovascular Events.

Abstract

BACKGROUND\nChest pain is a common presentation to the emergency department, and the best approach for risk stratification with long-term outcomes is limited. Our goal was to assess the utility of ankle-brachial index (ABI) in addition to stress testing among patients (males >40 and females >50 years old) who presented with chest pain, undetectable biomarkers, and unchanged electrocardiogram.\n\n\nMETHODS\nA total of 348 consecutive patients were enrolled in a prospective cohort study and completed an ABI and cardiovascular stress test.\n\n\nRESULTS\nPatients with an abnormal ABI were twice as likely to have an abnormal stress test (odds ratio = 2.03; 95% confidence interval [CI], 1.11-3.70). At 1 year, the incidence of adjusted major cardiovascular events (MCE) was lowest (8.2%) among those with a normal ABI and normal stress test. When compared with this low-risk group, the adjusted risk of 1-year MCE was 8.4% higher (95% CI, -1.0% to 17.8%; P = 0.080) in the normal ABI with abnormal stress test group; 5.3% higher (95% CI, -4.5% to 15.1%; P = 0.291) in the abnormal ABI with normal stress test group; and finally, 12.1% higher (95% CI, -2.5% to 26.6%; P = 0.105) in the abnormal ABI with abnormal stress test group.\n\n\nCONCLUSIONS\nAlthough additional research needs to be conducted, either an abnormal stress test or abnormal ABI suggested an increase of MCE at 1 year with abnormal stress test and ABI demonstrating the highest risk. The addition of ABI to patients undergoing stress testing may enhance risk stratification in patients who present with chest pain.