Data Registry Implantable Cardioverter-defibrillator Research Articles

Longitudinal Outcomes Associated With Non-Evidence-Based Implantable Cardioverter-Defibrillators Among Medicare Beneficiaries (From the National Cardiovascular Data Registry)

Primary prevention implantable cardioverter-defibrillators (ICDs) in patients with recent myocardial infarction or coronary revascularization and those with newly diagnosed or severe heart failure (HF) are considered non-evidence-based, as defined by pivotal randomized clinical trials. Although non-evidence-based ICDs have been associated previously with greater risk of in-hospital adverse events, longitudinal outcomes are not known. We used Medicare-linked data from the National Cardiovascular Data Registry's ICD Registry to identify patients discharged alive following first-time primary prevention ICD implantations performed between 2010 and 2013. We compared longitudinal outcomes, including all-cause mortality and all-cause hospital readmission among patients receiving non-evidence-based versus evidence-based ICDs, up to 4.75 years after implantation, using multivariable time-to-event analyses. Of 71,666 ICD implantations, 9,609 (13.4%) were classified as non-evidence-based. Compared to patients receiving evidence-based ICDs, non-evidence-based ICD recipients had greater mortality risk at 90 days (HR=1.44, CI: 1.37 - 1.52, p <0.0001) and at 1 year (HR=1.19, CI: 1.15 - 1.24, p <0.0001), but similar mortality risk at 3 years (HR=1.03, CI: 0.98 - 1.08, p=0.2630). Risk of all-cause hospitalization was higher in patients with non-evidence-based ICDs at 90 days (HR=1.17, CI: 1.14 - 1.20, p <0.0001), but the difference diminished at 1 year (HR=1.04, CI 1.00 - 1.07, p=0.0272) and at 3 years (HR=0.94, CI: 0.90 - 0.99, p=0.0105). In conclusion, among patients undergoing primary prevention ICD implantations between 2010 and 2013, those with non-evidence-based ICDs were at increased risk of mortality and readmission during longitudinal follow-up. Differences in the risk of mortality and hospitalization were highest in the first year following device implantation.

Temporal Trends in and FactorsAssociated With Use of Single-VersusDual-Coil Implantable Cardioverter-Defibrillator Leads: Data From the NCDR ICD Registry.

This analysis evaluated temporal trends and factors associated with the use of dual-coil implantable cardioverter-defibrillator (ICD) leads. Data suggest that dual-coil ICD leads are not associated with lower mortality and can be more difficult to extract than single-coil leads. A total of 435,772 patients at 1,690 hospitals underwent ICD lead insertion in the National Cardiovascular Data Registry's ICD Registry between April 2010 and December 2015. Hospitals were classified into 3 pre-specified groups (low, decreasing, or high use) based on the frequency of dual-coil lead use. Nationally, the use of dual-coil leads has decreased over time, from 87% of ICD leads in early 2010 to 55% at the end of 2015. Hospitals in the low-use (n= 292) or decreasing-use (n= 561) group had more ICDs inserted by electrophysiologists compared to the high-use (n= 837) group (90% or 80% vs 46%; p< 0.001 for both) and more extractions performed (median 7 or 11 vs 2; p< 0.001 for both). Despite statistical differences, there were no clinically significant differences in patient characteristics across all 3 groups. Although the use of dual-coil ICD leads has decreased over time, it continues to represent the majority of insertions in the United States. Hospital-level factors, but not patient factors, were associated with use of dual-coil ICD leads. Whether decreasing dual-coil ICD lead use has improved patient outcomes remains unknown and should be examined in large, multicenter, contemporaneous patient groups.

Abstract 9920: Outcomes Associated With Lead Abandonment versus Lead Extraction Strategies for Revision of Sterile Leads: An NCDR® Analysis

Introduction: While implantable cardioverter defibrillator (ICD) systems are lifesaving, leads often require replacement over time. When ICD leads require replacement, the existing lead can either be left in (abandoned) or be extracted, yet there are insufficient comparative data between these 2 strategies. Methods: We examined in-hospital events among propensity matched subjects undergoing lead replacement where the existing lead was either abandoned or extracted from National Cardiovascular Data Registry (NCDR) ICD Registry (2010 - 2011). Six month complication and 90-day and 1-year mortality rates were examined in a subset of Medicare subjects. We excluded those procedures involving infection and those performed by a cardiothoracic surgeon (extraction predetermined). Results: After 1:1 matching, we had 41744 subjects with in hospital outcomes, of which 2362 were Medicare aged and had 6-month complications and survival information. About 1/4 were women; average age was 66 yrs overall and 75 yrs in the Medicare cohort. In hospital events included 2.22% (n=463) and 3.63% (n=758) procedure related complications, and death in 0.21% (n=44) and 0.45% (n=94) in abandonment and extraction patients, respectively (p&lt;0.001 for both). In the Medicare cohort, at 6 months, there was no difference with respect to bleeding (4.92% vs 5.40%), tamponade (0.38% vs 0.66%), infection (2.27 % vs 3.03%), upper extremity thrombosis (0.76% vs 0.95%), pulmonary embolism (0.28% vs 0.57%), or urgent surgery (1.70% vs 0.85%) (p&gt;0.05 for all). At 90 days and 1 year, there was no difference in survival (p=0.55) (See Figure). Conclusion: Among propensity-matched patients undergoing ICD lead replacement, there were more in-hospital complications and deaths among extraction versus abandonment subjects. Among a Medicare subset, there were no differences in longer term outcomes. Thus, abandonment may be a reasonable alternative to extraction for sterile lead revision in some cases.

Defibrillator implantations for primary prevention in the United States: Inappropriate care or inadequate documentation: Insights from the National Cardiovascular Data ICD Registry

Prior studies have reported that more than 20% of implantable cardioverter-defibrillator (ICD) implantations in the United States do not adhere to trial-based criteria. We sought to investigate the patient characteristics associated with not meeting the inclusion criteria of the clinical trials that have demonstrated the efficacy of primary prevention ICDs. Using data from the National Cardiovascular Data Registry's ICD Registry, we identified patients who received ICDs for primary prevention from January 2006 to December 2008. We determined whether patients met the inclusion criteria of at least 1 of the 4 ICD primary prevention trials: Multicenter Automatic Defibrillator Implantation Trial (MADIT), MADIT-II, Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT), and the Multicenter Unsustained Tachycardia Trial (MUSTT). Among 150,264 patients, 86% met criteria for an ICD implantation based on trial data. The proportion of patients who did not meet trial-based criteria increased as age decreased. In multivariate analysis, the significant predictors for not meeting trial criteria included prior cardiac transplantation (odds ratio [OR] 2.1), pediatric electrophysiology operator (OR 2.0), and high-grade atrioventricular conduction disease (OR 1.4). Among National Cardiovascular Data Registry registrants receiving first-time ICDs for primary prevention, the majority met trial-based criteria. Multivariate analyses suggested that many patients who did not meet the trial-based criteria may have had clinical circumstances that warranted ICD implantation. These findings caution against the use of trial-based indications to determine site quality metrics that could penalize sites that care for younger patients. The planned incorporation of appropriate use criteria into the ICD registry may better characterize patient- and site-level quality and performance.

Primary prevention implantable cardioverter defibrillators in end-stage kidney disease patients on dialysis: a matched cohort study

Sudden cardiac death is the leading cause of death among end-stage kidney disease patients (ESKD) on dialysis, but the benefit of primary prevention implantable cardioverter defibrillators (ICDs) in this population is uncertain. We conducted this investigation to compare the mortality of dialysis patients receiving a primary prevention ICD with matched controls. We used data from the National Cardiovascular Data Registry's ICD Registry to select dialysis patients who received a primary prevention ICD, and the Get with the Guidelines-Heart Failure Registry to select a comparator cohort. We matched ICD recipients and no-ICD patients using propensity score techniques to reduce confounding, and overall survival was compared between groups. We identified 108 dialysis patients receiving primary prevention ICDs and 195 comparable dialysis patients without ICDs. One year (3-year) mortality was 42.2% (68.8%) in the ICD registry cohort compared with 38.1% (75.7%) in the control cohort. There was no significant survival advantage associated with ICD [hazard ratio (HR) 0.87, 95% confidence interval (CI) 0.66-1.13, log-rank P = 0.29]. After propensity matching, our analysis included 86 ICD patients and 86 matched controls. Comparing the propensity-matched cohorts, 1 year (3 years) mortality was 43.4% (74.0%) in the ICD cohort and 39.7% (76.6%) in the control cohort; there was no significant difference in mortality outcome between groups (HR = 0.94, 95% CI: 0.67-1.31, log-rank P = 0.71). We did not observe a significant association between primary prevention ICDs and reduced mortality among ESKD patients receiving dialysis. Consideration of the potential risks and benefits of ICD implantation in these patients should be undertaken while awaiting the results of definitive clinical trials.

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.

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. 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). 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.

Comparative Effectiveness of Cardiac Resynchronization Therapy With an Implantable Cardioverter-Defibrillator Versus Defibrillator Therapy Alone

Trials comparing implantable cardioverter-defibrillator (ICD) therapy with cardiac resynchronization therapy with a defibrillator (CRT-D) are limited to selected patients treated at centers with extensive experience. To compare outcomes after CRT-D versus ICD therapy in contemporary practice. Retrospective cohort study using the National Cardiovascular Data Registry's ICD Registry linked with Medicare claims. 780 U.S. hospitals implanting both CRT-D and ICD devices. 7090 propensity-matched patients older than 65 years with reduced left ventricular ejection fraction (&lt;0.35) and prolonged QRS duration on electrocardiography (≥120 ms) having CRT-D or ICD implantation between 1 April 2006 and 31 December 2009. Risks for death, readmission, and device-related complications over 3 years. Compared with ICD therapy, CRT-D was associated with lower risks for mortality (cumulative incidence, 25.7% vs. 29.8%; adjusted hazard ratio [HR], 0.82 [99% CI, 0.73 to 0.93]), all-cause readmission (cumulative incidence, 68.6% vs. 72.8%; adjusted HR, 0.86 [CI, 0.81 to 0.93]), cardiovascular readmission (cumulative incidence, 45.0% vs. 52.4%; adjusted HR, 0.80 [CI, 0.73 to 0.88]), and heart failure readmission (cumulative incidence, 24.3% vs. 29.4%; adjusted HR, 0.78 [CI, 0.69 to 0.88]). It was also associated with greater risks for device-related infection (cumulative incidence, 1.9% vs. 1.0%; adjusted HR, 1.90 [CI, 1.07 to 3.37]). The lower risks for heart failure readmission associated with CRT-D compared with ICD therapy were most pronounced among patients with left bundle branch block or a QRS duration at least 150 ms and in women. Patients were not randomly assigned to treatment groups, and few patients could be propensity-matched. The findings may not extend to younger patients or those outside of fee-for-service Medicare. In older patients with reduced left ventricular ejection fraction and prolonged QRS duration, CRT-D was associated with lower risks for death and readmission than ICD therapy alone. Agency for Healthcare Research and Quality.

Acute Lead Dislodgements and In-Hospital Mortality in Patients Enrolled in the National Cardiovascular Data Registry Implantable Cardioverter Defibrillator Registry

We sought to describe the incidence of acute lead dislodgements and the consequences of these events in patients enrolled in the National Cardiovascular Data Registry (NCDR) Implantable Cardioverter-Defibrillator (ICD) Registry. Lead dislodgements are common adverse events in patients undergoing ICD implants. Little is known regarding who is at risk and the consequences of these events. Patients enrolled between April 2006 and September 2008 were included. Acute lead dislodgement was defined as movement of the lead requiring another procedure for repositioning before discharge. Acute dislodgement occurred in 2,628 of 226,764 patients. Univariate variables associated with dislodgements included older age, female sex, and patients with atrial fibrillation, chronic lung disease, cerebrovascular disease, nonischemic cardiomyopathy, and lower ejection fractions (all p < 0.002). After multivariate adjustment, factors associated with an increased risk for dislodgement included New York Heart Association functional class IV heart failure, atrial fibrillation/flutter, having a cardiac resynchronization therapy-defibrillator device, and procedures performed by physicians trained under alternative pathways. A teaching/training hospital setting was not a factor (p = 0.64). Acute dislodgements had increased odds for other adverse events including cardiac arrest, cardiac tamponade, device infection, pneumothorax, and in-hospital death even after adjustment for potential confounders (all p < 0.0001). Acute lead dislodgements occur more often in patients with more comorbidities and in patients undergoing implants by nonelectrophysiology-trained implanters. These events were strongly associated with increased odds for in-hospital death.