Abstract 2435: Charlson Comorbidity Index and Risk of Cardiac Rhythm Device Generator Replacement: Results From the REPLACE Registry
Introduction: The complication rates from pacemaker (PPM) and implantable cardiac defibrillator (ICD) replacement procedures have recently been quantified from the prospective multicenter REPLACE Registry. The REPLACE Registry included patients undergoing generator replacement from all manufacturers without (Cohort 1) and with planned system modification (Cohort 2). We assessed the pre-specified hypothesis that the Charlson Comorbidity Index (CCI), a validated instrument summing individual risk factors weighted 1 to 6, would identify a subset of patients with increased risk of complications after cardiac rhythm management (CRM) generator replacement.
Methods: Patients undergoing elective CRM generator replacement from 68 US centers were enrolled, prospectively followed for 6 months, and data collected to determine pre-defined major and minor complication rates. All events were adjudicated by an independent, blinded clinical events committee. The CCI was calculated from baseline variables at the time of study enrollment. Comparisons were made based on median CCI and correlated with complication rate and device type.
Results: REPLACE enrolled 1031 patients in Cohort 1 who underwent generator replacement. An ICD was present in 49%, and a PPM in 51% of patients. The overall complication rate was 10.9% with a total complication rate of 8.5% in PPM patients and 13.3% in ICD patients. A CCI of ≤1 was present in 48% and CCI ≥2 in 52 % of patients. The CCI mean±SD in PPM patients was 1.9±2.3, versus 2.6±2.6 in ICD patients (p<0.001). In patients with a CCI of ≤1, the complication rate was 8.5% and 13.1% for a CCI of ≥2 (p=0.021). Stepwise logistic regression analysis resulted in an odds ratio (OR) of 1.54 for ICD versus PPM (p= 0.03), and an OR of 1.50 for CCI ≤1 versus CCI ≥2 (p=0.05).
Conclusions: ICD patients experienced a greater complication rate compared to PPM patients. ICD patients had a higher CCI than those with a PPM. Both CCI and device type were significant predictors of patients who experience a higher complication rate when undergoing CRM generator replacement.