Nonculprit Artery Myocardial Infarction and Complex Coronary Lesions in Anterior ST-Elevated Myocardial Infarction Patients: Data from the CIRCUS Study.

Aims: Periprocedural myocardial infarctions have been reported in the setting of planned percutaneous coronary intervention (PCI). We assessed the prevalence of nonculprit artery acute myocardial infarction (NCAMI) and its relationship with coronary artery characteristics, final infarct size, and 1-year adverse clinical outcomes in a population of anterior ST-elevated myocardial infarction (STEMI) patients.

Methods And Results: Late gadolinium-enhanced cardiac magnetic resonance (LGE-CMR) studies were performed within 7 days of admission in 129 anterior STEMI patients from the CIRCUS trial treated by primary PCI. Infarct in the noninfarct artery territory (circumflex, right coronary) was assessed on LGE-CMR and T2-weighted images. Eleven (8.5%) patients exhibited NCAMI. The only independent characteristic significantly associated with NCAMI was the presence of multiple complex coronary lesions (odds ratio = 12.9, 95% confidence interval [3.1-53.4]; p < 0.001). There was a significantly increased infarct size in NCAMI patients compared to patients without NCAMI (45.8 ± 20.4% of the left ventricle [LV] vs. 31.0 ± 15.1% of LV, respectively; p = 0.02), with lower LV ejection fraction (46 ± 10% vs. 34 ± 8%, respectively; p < 0.001).

Conclusion: NCAMIs are present in 8.5% of anterior STEMI patients and are significantly associated with multiple complex coronary lesions without significant relationship to any revascularization procedural technique. NCAMI was associated with a greater infarct size and reduced LVEF but not worse clinical outcomes at 1 year.