Study Assesses Impact of Lesion Severity on Coronary Event Risk
(HealthDay News) – Contrary to previous evidence, angiographic lesion severity may predict subsequent risk of ST-segment elevation myocardial infarction (STEMI) within three months, according to a study published in the July 15 issue of The American Journal of Cardiology.
To examine the impact of interval from initial angiogram to subsequent clinical event, Tarique Zaman, MD, of the Jacobi Medical Center in Bronx, NY, and colleagues conducted a study from 2003–2010. Participants in the study included 84 patients with non-STEMI (NSTEMI) and 41 patients with STEMI in vessels that had been evaluated in one or more previous angiographic studies but had not received a previous intervention.
The researchers found that, with an interval of more than three months from initial angiogram to MI event, 71% of STEMI and 63% of NSTEMI patients had <50% baseline stenosis at the target site. Lesions that resulted in a STEMI within three months or less of evaluation were more severe than those leading to STEMI more than three months after evaluation, with >50% stenosis seen in 57% of lesions. Most baseline lesions examined three months or less before STEMI showed significant luminal narrowing, although most MIs occurred at sites that did not have significant obstruction when examined more than three months prior to MI.
"In summary, this study proposes an explanation for the uncoupling of degree of narrowing in coronary arteries and subsequent events observed previously," the authors write. "Contrary to previous studies it shows that high-grade coronary stenosis may be an important predictor of STEMI in subsequent months."