Impact of institutional procedural volume on inhospital outcomes after cardiac resynchronization therapy device implantation: US national database 2003–2011

Abstract

The relationship between hospital volume and outcomes for cardiac resynchronization therapy (CRT) implantations has not been well established. The purpose of this study was to examine outcomes after CRT device implantation stratified by hospital volume using a large national inpatient database. Using the National Inpatient Sample database, we identified all patients undergoing de novo CRT implants between 2003 and 2011. Hospitals were categorized according to tertiles of annual CRT procedural volume. Rates of inhospital adverse events including death, cardiac perforation, pneumothorax, and lead revision were examined. A multivariate logistic regression analysis was performed to compare outcomes across hospital volume categories. Between 2003 and 2011, 410,104 de novo CRT implantations were performed. More than half (50.9%) of hospitals performed ≤16 CRT implants/y. Overall complication rates were higher in the lower-volume centers (3.9%, 3.5%, and 3.2%; P=.001) when stratified by first, second, and third tertiles of CRT volume, respectively. The lowest tertile of CRT volume was independently associated with increased inhospital all-cause mortality (adjusted odds ratio [OR] 1.37; 95% confidence interval [CI] 1.10-1.70; P = .005), any complication (adjusted OR 1.21, 95% CI 1.07-1.37; P = .003), and lead revision (adjusted OR 1.27; 95% CI 1.03-1.58; P = .03). Lower CRT hospital volume was associated with worse outcomes, including inhospital death, overall complications, and lead revision. Establishment of standards defining minimum CRT volume thresholds to identify centers of excellence may result in improved outcomes.