Left main and/or three-vessel disease in patients with non-ST-segment elevation myocardial infarction and low-risk GRACE score: Prevalence, clinical outcomes and predictors.

INTRODUCTION: A low-risk GRACE score identifies patients with a lower incidence of major cardiac events, however it can erroneously classify patients with severe coronary artery disease as low-risk. We assessed the prevalence, clinical outcomes and predictors of left main and/or three-vessel disease (LM/3VD) in non-ST-elevation acute myocardial infarction (NSTEMI) patients with a GRACE score of ≤108 at admission.

METHODS: Using data from the Portuguese Registry on Acute Coronary Syndromes, 1196 patients with NSTEMI and a GRACE score of ≤108 who underwent coronary angiography were studied. Independent predictors of LM/3VD and its impact on in-hospital complications and one-year mortality were retrospectively analyzed.

RESULTS: LM/3VD was present in 18.2% of patients. Its prevalence was higher in males and associated with hypertension, diabetes, previous myocardial infarction, heart failure and peripheral arterial disease (PAD). Although there were no differences in in-hospital complications, these patients had higher mortality (0.9 vs. 0.0%) and more major adverse cardiac and cerebrovascular events (MACCE) (4.1 vs. 2.5%, p=0.172), and higher one-year mortality (2.4 vs. 0.5%, p=0.005). Independent predictors of LM/3VD were age (OR 1.03; 95% CI 1.01-1.0, p=0.003), male gender (OR 2.56; 95% CI 1.56-4.17, p<0.001), heart rate (1.02; 95% CI 1.01-1.03, p<0.001), PAD (OR 3.21; 95% CI 1.47-7.00, p<0.001) and heart failure (OR 3.38; 95% CI 1.02-11.15, p=0.046).

CONCLUSIONS: LM/3VD was found in one in five patients. These patients had a tendency for higher in-hospital mortality and more MACCE, and higher one-year mortality. Simple clinical variables could help predict this severe coronary anatomy.