The Impact of SYNTAX Score of Non-Infarct-Related Artery on Long- Term Outcome among Patients with Acute ST Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

OBJECTIVE: We investigated the impact of the severity of stenosis in a non-infarct-related artery (IRA) on the long-term prognosis of patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). METHODS: Three hundred one consecutive patients (age: 59.7 ± 13.2 years, 85.5% men) underwent primary PCI during 2009–2012. Receiver operating characteristic curve analysis found the optimal cutoff for non-IRA SYNTAX score (SS) to be 2.5. We divided the patients into two groups according to this cutoff value. RESULTS: By multivariable analysis, non-IRA SS (≥2.5) was an independent predictor of major adverse cardiac events (hazard ratio [HR]: 2.15, 95% confidence interval [CI]: 1.21–3.79, P = 0.008) and all-cause mortality (HR: 3.49, 95% CI: 1.13–10.8, P = 0.03). However, the prediction of cardiovascular mortality had only borderline significance (HR: 3.29, 95% CI: 0.90–12.08, P = 0.07). CONCLUSION: STEMI patients treated with primary PCI and moderate to severe non-IRA stenosis (SS ≥2.5) have more subsequent cardiac events. Those populations should be treated with more aggressive preventive and medical management.