Use and Outcomes of Dual Chamber or Cardiac Resynchronization Therapy Defibrillators Among Older Patients Requiring Ventricular Pacing in the National Cardiovascular Data Registry Implantable Cardioverter Defibrillator Registry.

Importance: Frequent right ventricular (RV) pacing can cause and exacerbate heart failure. Cardiac resynchronization therapy (CRT) has been shown to be associated with improved outcomes among patients with reduced left ventricular ejection fraction who need frequent RV pacing, but the patterns of use of CRT vs dual chamber (DC) devices and the associated outcomes among these patients in clinical practice is not known. Objective: To assess outcomes, variability in use of device type, and trends in use of device type over time among patients undergoing implantable cardioverter defibrillator (ICD) implantation who were likely to require frequent RV pacing but who did not have a class I indication for CRT. Design, Setting, and Participants: This retrospective cohort study used the National Cardiovascular Data Registry (NCDR) ICD Registry. A total of 3100 Medicare beneficiaries undergoing first-time implantation of CRT defibrillator (CRT-D) or DC-ICD from 2010 to 2016 who had a class I or II guideline ventricular bradycardia pacing indication but not a class I indication for CRT were included. Data were analyzed from August 2018 to October 2019. Exposures: Implantation of a CRT-D or DC-ICD. Main Outcomes and Measures: All-cause mortality, heart failure hospitalization, and complications were ascertained from Medicare claims data. Multivariable Cox proportional hazards models and Fine-Gray models were used to evaluate 1-year mortality and heart failure hospitalization, respectively. Multivariable logistic regression was used to evaluate 30-day and 90-day complications. All models accounted for clustering. The median odds ratio (MOR) was used to assess variability and represents the odds that a randomly selected patient receiving CRT-D at a hospital with high implant rates would receive CRT-D if they had been treated at a hospital with low CRT-D implant rates. Results: A total of 3100 individuals were included. The mean (SD) age was 76.3 (6.4) years, and 2500 (80.6%) were men. The 1698 patients (54.7%) receiving CRT-D were more likely than those receiving DC-ICD to have third-degree atrioventricular block (828 [48.8%] vs 432 [30.8%]; P < .001), nonischemic cardiomyopathy (508 [29.9%] vs 255 [18.2%]; P < .001), and prior heart failure hospitalizations (703 [41.4%] vs 421 [30.0%]; P < .001). Following adjustment, CRT-D was associated with lower 1-year mortality (hazard ratio [HR], 0.70; 95% CI, 0.57-0.87; P = .001) and heart failure hospitalization (subdistribution HR, 0.77; 95% CI, 0.61-0.97; P = .02) and no difference in complications compared with DC-ICD. Hospital variation in use of CRT was present (MOR, 2.00), and the use of CRT in this cohort was higher over time (654 of 1351 [48.4%] in 2010 vs 362 of 594 [60.9%] in 2016; P < .001). Conclusions and Relevance: In this cohort study of older patients in contemporary practice undergoing ICD implantation with a bradycardia pacing indication but without a class I indication for CRT, CRT-D was associated with better outcomes compared with DC devices. Variability in use of device type was observed, and the rate of CRT implantation increased over time.

Use of cell phone adapters is associated with reduction in disparities in remote monitoring of cardiac implantable electronic devices.

BACKGROUND: Remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) is standard of care. However, it is underutilized. In July 2012, our institution began providing cell phone adapters (CPAs) to patients free of charge following CIED implantation to improve remote transmission (RT) adherence. METHODS: Patients in our institution's RM database from January 1, 2010, thru June 30, 2015, were retrospectively reviewed. There were 2157 eligible patients. Remote transmission proportion (RTP) and time to transmission (TT) were compared pre- and post-implementation of free CPA. Chi-squared analysis and Kruskal-Wallis tests were performed to compare RTP and TT. RESULTS: There was a significant increase in RTP (134 [18.4%] vs 99 [54.7%]; p < 0.001) and decrease in median TT in days (189[110-279] vs 58 [10-149]; p < 0.001) after CPAs were provided to patients. Caucasian patients were more likely than African Americans and Hispanics to use RM prior to CPAs (p = 0.04). After the implementation of CPAs, there was a significant increase in RTP for all racial groups (< 0.001) with no difference in RTP among racial groups (p = 0.18). The RTP for urban residents was significantly greater than non-urban residents with CPAs (p = 0.008). Patients greater than 70 years of age were significantly less likely to participate in RT before and after CPAs were provided (p = 0.03, p = 0.01, respectively). CONCLUSIONS: CPAs significantly improve RTP and reduce median TT for all patients regardless of race, geographic residence, and age (> 70 years old to lesser extent). Broad institution of CPAs following ICD implantation could potentially reduce disparity in RTP and deserves more study.

Survival After Secondary Prevention Implantable Cardioverter-Defibrillator Placement: An Analysis From the NCDR ICD Registry.

OBJECTIVES: This study sought to define the characteristics and risks of death of patients receiving a physician-designated secondary prevention implantable cardioverter-defibrillator (ICD) in contemporary clinical practice. BACKGROUND: Data on utilization and outcomes of ICDs for the secondary prevention of sudden cardiac death (SCD) are limited. METHODS: Patients enrolled in the National Cardiovascular Data Registry's (NCDR) ICD Registry from 2006 to 2009 with a physician-designated secondary prevention indication for ICD implantation were identified and linked to the Social Security Death Master File. Those patients with a history either of tachycardic arrest or sustained ventricular tachycardia (SCD/VT) or of syncope without SCD/VT were included. Kaplan-Meier survival analysis was used to assess mortality. Cox proportional hazards survival modeling was used to assess the risk of death in these groups, adjusting for patient characteristics. RESULTS: In the study cohort of 46,685 patients (mean age 66 ± 14 years, 73.5% male, 85% white), 78% had SCD/VT and 22% had syncope. Overall mortality was 10.4% at 1 year and 16.4% at 2 years. Compared with patients having SCD/VT, the adjusted hazard of death at 1 year was lower in the patients having syncope (hazard ratio: 0.89; 95% confidence interval: 0.83 to 0.96) but was not significantly different by 2 years (hazard ratio: 0.96; 95% confidence interval: 0.90 to 1.01). CONCLUSIONS: Nearly 9 of 10 patients receiving a secondary prevention ICD in clinical practice are alive 1 year after implantation. The risk of death varies by indication and is highest among patients who survive SCD or sustained VT in the first year after device implantation.

Temporal trends in patient characteristics and outcomes among Medicare beneficiaries undergoing primary prevention implantable cardioverter-defibrillator placement in the United States, 2006-2010. Results from the National Cardiovascular Data Registry's Implantable Cardioverter-Defibrillator Registry.

BACKGROUND: Contemporary patterns of use and outcomes of implantable cardioverter-defibrillators (ICDs) in community practice settings are not well characterized. We assessed temporal trends in patient characteristics and outcomes among older patients undergoing primary prevention ICD therapy in US hospitals between 2006 and 2010. METHODS AND RESULTS: Using the National Cardiovascular Data Registry's ICD Registry, we identified Medicare fee-for-service beneficiaries aged ≥65 years and older with left ventricular ejection fraction ≤35% who underwent primary prevention ICD implantation, including those receiving concomitant cardiac resynchronization therapy between 2006 and 2010 and could be matched to Medicare claims. Outcomes were mortality and hospitalization (all-cause and heart failure) at 180 days, and device-related complications. We used multivariable hierarchical logistic regression to assess temporal trends in outcomes accounting for changes in patient, physician, and hospital characteristics. The cohort included 117 100 patients. Between 2006 and 2010, only modest changes in patient characteristics were noted. Fewer single lead devices and more cardiac resynchronization therapy devices were used over time. Between 2006 and 2010, there were significant improvements in all outcomes, including 6-month all cause mortality (7.1% in 2006, 6.5% 2010; adjusted odds ratio, 0.88; 95% confidence interval, 0.82-0.95), 6-month rehospitalization (36.3% in 2006, 33.7% in 2010; adjusted odds ratio, 0.87; 95% confidence interval, 0.83-0.91), and device-related complications (5.8% in 2006, 4.8% in 2010; adjusted odds ratio, 0.80; 95% confidence interval, 0.74-0.88). CONCLUSIONS: The clinical characteristics of this national population of Medicare patients undergoing primary prevention ICD implantation were stable between 2006 and 2010. Simultaneous improvements in outcomes suggest meaningful advances in the care for this patient population.