Impact of Annual Operator and Institutional Volume on Percutaneous Coronary Intervention Outcomes: A 5-Year United States Experience (2005 - 2009)
Background—The relationship between operator or institutional volume and outcomes amongst patients undergoing percutaneous coronary interventions (PCI) is unclear.
Methods and Results—Cross sectional study based on the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample between 2005-2009. Subjects were identified by International Classification of Diseases, 9th Revision, Clinical Modification procedure code, 36.06 and 36.07. Annual operator and institutional volumes were calculated using unique identification numbers and then divided into quartiles. Three level hierarchical multivariate mixed models were created. The primary outcome was in-hospital mortality; secondary outcome was a composite of in-hospital mortality and peri-procedural complications. A total of 457,498 PCIs were identified representing a total of 2,243,209 PCIs performed in the US during the study period. Overall in-hospital, all-cause mortality was 1.08%, and the overall complication rate was 7.10%. The primary and secondary outcomes of procedures performed by operators in 4th [annual procedural volume; primary and secondary outcomes] [>100; 0.59% and 5.51%], 3rd [45-100; 0.87% and 6.40%], and 2nd quartile [16-44; 1.15% and 7.75%] were significantly less (p<0.001) when compared to those by operators in the 1st quartile [<=15; 1.68% and 10.91%]. Spline analysis also showed significant operator and institutional volume outcome relationship. Similarly operators in the higher quartiles witnessed a significant reduction in length of hospital stay (LOS) and cost of hospitalization (p<0.001).
Conclusions—Overall in-hospital mortality after PCI is low. An increase in operator and institutional volume of PCI was found to be associated with a decrease in adverse outcomes, LOS, and cost of hospitalization.
- Operator volume
- Institutional volume
- percutaneous coronary intervention
- hospital costs
- hospital stay
- Received February 13, 2014.
- Revision received July 15, 2014.
- Accepted August 4, 2014.