Abstract 4127: Dual Chamber ICD Selection is Associated with Racial and Socioeconomic Disparities and Increased Complication Rates Among Patients Enrolled in the NCDR ICD Registry
Background: Dual chamber implantable cardioverter-defibrillators (ICDs) offer potential advantages over single chamber devices. Definitive evidence demonstrating improved outcomes with dual chamber ICDs is lacking, however, and the choice of such devices remains controversial. The prevalence, predictors, and procedural complication rates of single versus dual chamber devices in patient populations not enrolled in randomized trials are unknown.
Methods and Results: Between January 2006 and December 2007, the NCDR ICD Registry recorded 104,049 first-time implantations of single or dual chamber ICDs. Dual chamber devices were implanted in 64,489 patients (62%). After adjusting for potential confounding factors and clustering on patient center using hierarchical logistic regression models, characteristics associated with lower odds of dual chamber ICD implantation included black race (odds ratio (OR), 0.89; 95% confidence interval (CI), 0.85 – 0.93), Medicaid insurance (OR, 0.88; CI, 0.82 – 0.94), diabetes (OR, 0.94; CI, 0.91 – 0.97), and end-stage renal disease (OR, 0.82; CI, 0.76 – 0.89). Complications were more frequent with dual chamber device implantation, including cardiac arrest (0.31% vs. 0.23%, P = 0.01), hematoma (0.92% vs. 0.71%, P < 0.001), pneumothorax (0.53% vs. 0.36%, P < 0.001), pericardial tamponade (0.09% vs. 0.05%, P = 0.01), lead dislodgement (0.88% vs. 0.50%, P < 0.001), and any complication (3.2% vs. 2.1%, P < 0.001). The increased risk of complications associated with dual chamber ICD selection persisted after adjusting for patient demographic characteristics, medical comorbidities, and ICD indication (OR, 1.40; CI, 1.28 – 1.52; P < 0.001).
Conclusions: While dual chamber ICD selection is more common than single chamber implantation among patients enrolled in the NCDR ICD Registry, both blacks and patients insured with Medicaid are less likely to receive dual chamber devices. Further investigation is needed to determine whether the benefits of dual chamber ICD therapy outweigh the greater risk of peri-procedural complications.