PCI Outcomes Evaluated in Relation to Procedural Characteristics and Operator Volumes

June 12, 2017—In a study published in Journal of the American College of Cardiology (JACC), Alexander C. Fanaroff, MD, et al describe percutaneous coronary intervention (PCI) operator procedure volumes, characteristics of low-, intermediate-, and high-volume operators, and the relationship between operator volume and clinical outcomes in a large, contemporary, nationwide sample in the United States (2017;69:2913–2924).

The investigators advised that the background of the study is that the professional guidelines have reduced the recommended minimum number to an average of 50 PCI procedures performed annually by each operator; however, operator volume patterns and associated outcomes since this change are unknown.

As summarized in JACC, the investigators used data from the National Cardiovascular Data Registry that were collected between July 1, 2009, and March 31, 2015. They examined operator annual PCI volume and divided operators into low- (< 50 PCIs/y), intermediate- (50–100 PCIs/y), and high-volume (> 100 PCIs/y) groups, and then determined the adjusted association between annual PCI volume and in-hospital outcomes, including mortality.

The median annual number of procedures performed per operator was 59; 44% of operators performed < 50 PCI procedures per year.

The investigators found that low-volume operators more frequently performed emergency and primary PCI procedures and practiced at hospitals with lower annual PCI volumes. Unadjusted in-hospital mortality was 1.86% for low-volume operators, 1.73% for intermediate-volume operators, and 1.48% for high-volume operators. The adjusted risk of in-hospital mortality was higher for PCI procedures performed by low- and intermediate-volume operators compared with those performed by high-volume operators (adjusted odds ratio was 1.16 for low volume vs high volume; adjusted odds ratio was 1.05 for intermediate volume vs high volume), as was the risk for new dialysis after PCI. No volume relationship was observed for post-PCI bleeding.

The investigators concluded that many PCI operators in the United States are performing fewer than the recommended number of PCI procedures annually. Although absolute risk differences are small and may be partially explained by unmeasured differences in case mix between operators, there remains an inverse relationship between PCI operator volume and in-hospital mortality that persisted in risk-adjusted analyses, reported the investigators in JACC.