Background: Among patients hospitalized for an ST-elevation myocardial infarction, the presence of concomitant angiographically severe (≥70%) stenoses in noninfarct-related coronary arteries is associated with poorer in-hospital outcomes. However, there are limited data on patients with angiographically mild-to-moderate (< 70%) noninfarct-related artery (IRA) stenoses.
Methods: We studied 642 consecutive patients with a first STelevation myocardial infarction presenting to a tertiary medical center. We compared the clinical characteristics and outcomes of patients with isolated IRA disease versus patients with one or more mild-to-moderate non-IRA stenoses versus patients with one or more severe non-IRA stenoses.
Results: Of the 642 patients, 29.8% had isolated IRA disease, 22.6% had one or more mild-to-moderate non-IRA stenoses and 47.7% had one or more severe non-IRA stenoses. The age distribution was 54±12 versus 57±12 versus 58±11 years, with a P value of less than 0.001 and the diabetes prevalence was 27, 28, and 40%, respectively (P=0.003). Among the three groups, the in-hospital mortality was 3.1, 5.5, and 9.8% (P=0.013), the left ventricular ejection fraction was 48, 48, and 45% (P=0.013), and the rate of revascularization was 98, 95, and 88%, respectively (P<0.001).
Conclusion: Patients with one or more mild-to-moderate non-IRA stenoses had favorable in-hospital outcomes that were comparable with the patients with isolated IRA disease, despite having adverse clinical characteristics that were similar to patients with severe non-IRA stenoses. These results highlight the incremental prognostic importance of angiographical data in patients with ST-elevation myocardial infarction. More research is needed to understand the influence of mild-to-moderate non-IRA stenoses on late outcomes.