Trends and outcomes of cardiac resynchronization therapy upgrade procedures: A comparative analysis using a United States National Database 2003-2013

BACKGROUND While outcomes after de novo cardiac resynchronization therapy (CRT) implantations have been reported, there are limited data on CRT upgrade procedures. OBJECTIVE The purpose of this study was to examine trends and inhospital outcomes of patients undergoing CRT upgrade procedures by using a large national inpatient database. METHODS Using the National Inpatient Sample database, we identified all patients undergoing CRT upgrade and de novo CRT implants between 2003 and 2013. Rates of in-hospital adverse events such as death, cardiac perforation, pneumothorax, and lead revision were examined. Multivariate regression analysis was performed to compare outcomes after CRT upgrade and those after de novo CRT implant procedures. RESULTS Between 2003 and 2013, 19,546 CRT upgrade procedures and 464,246 de novo CRT implants were recorded. Rates of in-hospital mortality of patients undergoing CRT upgrade were significantly higher than those of patients undergoing de novo CRT implant (1.9% vs 0.8%; P,.001). Compared with de novo CRT implants, CRT upgrades were independently associated with increased mortality (adjusted odds ratio [OR] 1.91; 95% confidence interval [CI] 1.67-2.19; P,.001), cardiac perforation (OR 3.20; 95% CI 2.71-3.77; P,.001), and need for lead revision (OR 2.09; 95% CI 1.88-2.3; P,.001). CONCLUSION In a large national inpatient cohort, CRT upgrade procedures were associated with higher rates of in-hospitalmortality and procedural complications as compared with de novo CRT implants.