Long-term outcomes and operators' experience in primary percutaneous coronary intervention for ST-segment elevation myocardial infarction.

Primary percutaneous coronary intervention (pPCI) for ST-segment elevation myocardial infarction (STEMI) is typically performed by experienced operators. Therefore, the safety of pPCI for STEMI performed by less experienced operators with the support of experienced operators remains unknown. We aimed to investigate the long-term outcomes of pPCI for STEMI performed by less experienced operators with the support of experienced operators. In total, 775 STEMI patients were enrolled and divided into groups according to operator experience in PCI: less experienced (n = 384) and experienced (n = 391) operator groups. Experienced operators were defined as those who had performed > 50 elective PCI procedures per year as the first operator or instructional assistant, whereas less experienced operators were defined as others. When less experienced operators performed the pPCI, experienced operators supported them. The primary endpoint was any cardiovascular event, defined as a composite of cardiovascular death, nonfatal myocardial infarction, and unplanned hospitalization for heart failure. In the propensity score-matched analysis, 324 patients were included in each group. The cumulative incidence of the primary endpoint over a median of 5 years in the less experienced operator group was similar to that in the experienced operator group (15% vs. 18%, P = 0.209). In the multivariate Cox proportional hazards model, there was no excess risk for patients operated upon by less experienced operators for the primary endpoint (adjusted hazard ratio, 0.85; 95% confidence interval, 0.58-1.25; P = 0.417). pPCI for STEMI by less experienced operators did not increase the risk of in-hospital mortality or 5-year long-term cardiovascular events if supported by experienced operators.