Abstract 2808: Prognostic Implications of Elevated Troponin in Patients with Suspected Acute Coronary Syndrome With Nonobstructive Coronary Disease
Background Acute Coronary Syndromes (ACS) account for over 1.4 million hospitalizations annually in the United States. A subgroup of ACS patients arenoted to have elevated troponin levels without critical epicardial CAD on angiography. The goal of this project is to elucidate risk factors, treatment strategies, and prognostic implications in this selected patient population.
Methods Between January 2003 and December 2005, 800 patients with suspected ACS underwent coronary angiography at Ben Taub Hospital in Houston, Texas. Upon review, 83 patients were identified to have elevated troponin levels and less than 50% stenosis of any major coronary artery on angiography. We performed a chart review to evaluate risk profiles and a primary combined endpoint of death or repeat myocardial infarction (MI) over a follow up period of 2.5 years. Baseline characteristics were identified, including mean troponin level, and the presence of cardiac risk factors. Outcomes were then compared to 78 matched controls without troponin elevation and without critical epicardial disease over a follow up period of 2.5 years.
Results Study patients presented with a mean troponin level of 32 ng/ml, versus control patients who presented with mean troponin level of 0.298 ng/ml (p = <0.001). Patients who presented with elevated troponin had a significant increased rate of primary combined endpoint of death or repeat MI, as well as, individual outcomes of repeat MI or death from all causes (table⇓)
Conclusions Patients with elevated troponin and nonobstructive coronary disease have an increased incidence of death and recurrence of cardiac injury at 2.5 year follow up compared to matched controls. Compared to patients with similar diagnosis, elevated troponin is an independent marker of poor prognosis. The results of this study implicate that these patients require aggressive risk factor modification and treatment of underlying disease, in order to reduce risks for future adverse events.