Association between the mortality rate and operator volume in patients undergoing emergency or elective percutaneous coronary interventions.

Background: Previous studies have suggested that low operator and institutional volume may be associated with an increased risk of adverse events in patients undergoing percutaneous coronary intervention (PCI).
Aims: The aim of the study was to assess the relationship between operator volume and procedure- -related mortality in the emergent and elective settings.
Methods: Data were obtained from a national registry of PCIs, maintained in cooperation with the Association of Cardiovascular Interventions of the Polish Cardiac Society. Registry data for the period from January 2014 to December 2017 were collected. During the study, there were 162 active catheterization laboratories, in which a total of 456 732 PCIs were performed.
Results: The median number of PCIs performed in a single laboratory was 2643.5 (interquartile range [IQR], 1875-3598.5) over 4 years. The median number of PCIs performed by a single operator was 557 (IQR, 276.25-860.5) per year. We did not confirm a significant relationship between the operator volume and mortality in the overall group of patients treated with emergency and elective PCI. However, we noted a lower mortality rate for high-‑volume operators (odds ratio [OR], 0.79; 95% CI, 0.63-0.99; P = 0.04). When the operator volume was assessed as a continuous variable, there was a trend toward significance (OR, 0.94; 95% CI; 0.88-1.0007; P = 0.052) in patients treated with emergency PCI.
Conclusions: High operator volume was associated with a lower periprocedural mortality rate than low operator volume in patients undergoing PCI due to acute coronary syndromes.