Primary Prevention Implantable Cardioverter-defibrillator Placement Research Articles

Racial differences in setting of implantable cardioverter-defibrillator placement in older adults with heart failure and association with disparate post-implant outcomes.

Implantable cardioverter-defibrillator (ICD) placement in heart failure (HF) patients during or early after (≤90 days) unplanned cardiovascular hospitalizations has been associated with poor outcomes. Racial and ethnic differences in this "peri-hospitalization" ICD placement have not been well described. Using a 20% random sample of Medicare beneficiaries, we identified older (≥66 years) patients with HF who underwent ICD placement for primary prevention from 2008 to 2018. We investigated racial and ethnic differences in frequency of peri-hospitalization ICD placement using modified Poisson regression. We utilized Kaplan-Meier analyses and Cox regression to investigate the association of peri-hospitalization ICD placement with differences in all-cause mortality and hospitalization (HF, cardiovascular and all-cause) within and between race and ethnicity groups for up to 5-year follow-up. Among the 61,710 beneficiaries receiving ICDs (35% female, 82% White, 10% Black, 6% Hispanic), 44% were implanted peri-hospitalization. Black [adjusted rate ratio (RR) 95% Confidence Interval (95% CI): 1.16 (1.12, 1.20)] and Hispanic [RR (95% CI): 1.10 (1.06, 1.14)] beneficiaries were more likely than White beneficiaries to have ICD placement peri-hospitalization. Peri-hospitalization ICD placement was associated with an at least 1.5× increased risk of death, 1.5× increased risk of re-hospitalization and 1.7× increased risk of HF hospitalization during 3-year follow-up in fully adjusted models. Although beneficiaries with peri-hospitalization placement had the highest mortality and readmission rates 1- and 3-year post-implant (log-rank p < 0.0001), the magnitude of the associated risk did not differ significantly by race and ethnicity (p = NS for interaction). ICD implantation occurring during the peri-hospitalization period was associated with worse prognosis and occurred at higher rates among Black and Hispanic compared to White Medicare beneficiaries with HF during the period under study. The risk associated with peri-hospitalization ICD placement did not differ by race and ethnicity. Future paradigms aimed at enhancing real-world effectiveness of ICD therapy and addressing disparate outcomes should consider timing and setting of ICD placement in HFrEF patients who otherwise meet guideline eligibility.

Wearable defibrillator use in patients with high risk of sudden cardiac death: a brief report from a single center

Devices such as implantable cardioverter defibrillators (ICDs) and wearable cardioverter defibrillators (WCDs) have opened up new paths in the treatment of Sudden Cardiac Death. Guidelines advocate ICD placement for primary prevention after at least three months of optimal medical therapy following the first diagnosis of heart failure with reduced FE from any cause, and at least 40 days after an acute myocardial infarction with FE 35% notwithstanding medication. In these and other cases documented in the guidelines, the use of a wearable defibrillator (WCD), a noninvasive device that guards against malignant arrhythmias while waiting for arrhythmic risk to be defined and medication therapy to be optimized, may be considered. In our Cardiology/Utic Department, we treated 26 patients with a preliminary indication for ICD implantation: the use of the WCD allowed us to swiftly put them in clinical safety, avoiding potentially fatal arrhythmias while waiting for pharmacological therapy to be optimized. At the end of the periodic follow-up, FE had normalized in ten patients, allowing them to avoid ICD. Only 10 of the 26 participants with WCD had a proven indication for final implantation. There were no fatalities or problems in any of the patients.

Abstract 13009: Time to Implantable Cardioverter Defibrillator in Patients With Left Ventricular Ejection Fraction ≤ 35%

Background: Implantable cardioverter-defibrillators (ICDs) are endorsed by the current American Heart Association (AHA) Guidelines as the cornerstone in the primary prevention of mortality in patients with reduced ejection fraction (EF) (≤35%). The timing for ICD therapy in non-ischemic cardiomyopathy (NICM) is not specified in the current guidelines. The objective of this study was to determine the timing for ICD insertion for patients with NICM versus ICM in the real-world population. Methods: Retrospective design study of patients with ICDs implantation from 2019 to 2022 at our community hospital. Data was obtained via the Device Implant Registry. All eligible participants had confirmed diagnosis of ICM and NICM on chart review; while confirmed EF≤35% on echocardiography. Categorical predictors and clinical outcomes were analyzed using Pearson’s chi-square test or Fisher’s exact test. Quantitative predictors and clinical outcomes were analyzed using Student's t-test or the Wilcoxon rank sum test. Results: Our cohort included 62 patients undergoing ICD placement for primary prevention. There was no statistical significance between patients based on age, sex, race, and EF. Average time to ICD placement was 134 days for patients with ICM and 274 days for patients with NICM, a difference that favoured NICM; p =0.009 ( p &lt;0.05). In the majority of patients, 64.5%, ICD implantation was deferred for at least 90 days compared to 35.5% patients who had an ICD placed by 90 days; p =0.001 ( p &lt;0.05). The mortality in our study was 13% over a median of 2 years, with a predominance of ICM as compared to NICM, 75% versus 25%, respectably. Logistics regression demonstrated that timing to ICD implantation was not an independent variable of mortality. The mean overall survival was 274.4 days (SD +/- 50) in NICM compared to 134.3 days (SD +/- 21) in the ICM group, p =0.007 ( p &lt;0.05). Conclusions: In a real-world population, time to ICD implantation was statistically different in ICM compared to NICM. ICM remains a significant risk of all-cause mortality despite the progress made in both medical and procedural treatments. Further studies are necessary to determine the appropriate time to ICD implantation in patients with NICM and reduced EF.

Combination of late gadolinium enhancement and genotype improves prediction of prognosis in non‐ischaemic dilated cardiomyopathy

AimsGenotype and left ventricular scar on cardiac magnetic resonance (CMR) are increasingly recognized as risk markers for adverse outcomes in non‐ischaemic dilated cardiomyopathy (DCM). We investigated the combined influence of genotype and late gadolinium enhancement (LGE) in assessing prognosis in a large cohort of patients with DCM.Methods and resultsOutcomes of 600 patients with DCM (53.3 ± 14.1 years, 66% male) who underwent clinical CMR and genetic testing were retrospectively analysed. The primary endpoints were end‐stage heart failure (ESHF) and malignant ventricular arrhythmias (MVA). During a median follow‐up of 2.7 years (interquartile range 1.3–4.9), 24 (4.00%) and 48 (8.00%) patients had ESHF and MVA, respectively. In total, 242 (40.3%) patients had pathogenic/likely pathogenic variants (positive genotype) and 151 (25.2%) had LGE. In survival analysis, positive LGE was associated with MVA and ESHF (both, p < 0.001) while positive genotype was associated with ESHF (p = 0.034) but not with MVA (p = 0.102). Classification of patients according to genotype (G+/G−) and LGE presence (L+/L−) revealed progressively increasing events across L−/G−, L−/G+, L+/G− and L+/G+ groups and resulted in optimized MVA and ESHF prediction (p < 0.001 and p = 0.001, respectively). Hazard ratios for MVA and ESHF in patients with either L+ or G+ compared with those with L−/G− were 4.71 (95% confidence interval: 2.11–10.50, p < 0.001) and 7.92 (95% confidence interval: 1.86–33.78, p < 0.001), respectively.ConclusionClassification of patients with DCM according to genotype and LGE improves MVA and ESHF prediction. Scar assessment with CMR and genotyping should be considered to select patients for primary prevention implantable cardioverter‐defibrillator placement.

External Validation of a Risk Prediction Model for Ventricular Arrhythmias in Arrhythmogenic Right Ventricular Cardiomyopathy

The new 5-year ventricular arrhythmia (VA) occurrence risk model is a major breakthrough for arrhythmia risk stratification in the challenging population of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). In the original study, the model resulted in a 20.6% reduction in implantable cardioverter-defibrillator (ICD) placement compared with the 2015 consensus, for the same protection level. However, only internal validation was performed, limiting generalisation. We externally validated the model in a European tertiary care cohort of 128 patients with ARVC with restrictive indications for primary prevention ICD placement. Overall, 74% were men, none had VA history, and a single patient had an ICD at baseline. Median age at diagnosis was 38 years (interquartile range [IQR] 28-50). During a median follow-up of 7.8 years (IQR 6.1-9.7), 15 patients (12%) experienced VA. The model provided good discrimination, with a C-index for 5-year VA risk prediction of 0.84 (95% confidence interval 0.74-0.93). However, the model led to an overestimation of the 5-year VA risk when applying thresholds < 50%. With a < 10% predicted risk, no patient showed VA. With a 7.5% predicted risk, the ICD:VA ratio was 6.3 vs 3.4 in the original study. The model still outperformed the 2015 International Task Force Consensus. Overall, in a relatively large European ARVC cohort with restrictive indications for ICD placement, the ARVC model for VA prediction successfully identified ARVC patients with VA during follow-up. Yet, our study underscores the need for careful threshold selection, considering the model’s associated risk overestimation in low- to intermediate-risk patients.

Relationship of LVEF and Myocardial Scar to Long-Term Mortality Risk and Mode of Death in Patients With Nonischemic Cardiomyopathy.

Nonischemic cardiomyopathy is a leading cause of reduced left ventricular ejection fraction (LVEF) and is associated with high mortality risk from progressive heart failure and arrhythmias. Myocardial scar on cardiovascular magnetic resonance imaging is increasingly recognized as a risk marker for adverse outcomes; however, left ventricular dysfunction remains the basis for determining a patient's eligibility for primary prophylaxis with implantable cardioverter-defibrillator. We investigated the relationship of LVEF and scar with long-term mortality and mode of death in a large cohort of patients with nonischemic cardiomyopathy. This study is a prospective, longitudinal outcomes registry of 1020 consecutive patients with nonischemic cardiomyopathy who underwent clinical cardiovascular magnetic resonance imaging for the assessment of LVEF and scar at 3 centers. During a median follow-up of 5.2 (interquartile range, 3.8, 6.6) years, 277 (27%) patients died. On survival analysis, LVEF ≤35% and scar were strongly associated with all-cause (log-rank test P=0.002 and P<0.001, respectively) and cardiac death (P=0.001 and P<0.001, respectively). Whereas scar was strongly related to sudden cardiac death (SCD; P=0.001), there was no significant association between LVEF ≤35% and SCD risk (P=0.57). On multivariable analysis including established clinical factors, LVEF and scar are independent risk markers of all-cause and cardiac death. The addition of LVEF provided incremental prognostic value but insignificant discrimination improvement by C-statistic for all-cause and cardiac death, but no incremental prognostic value for SCD. Conversely, scar extent demonstrated significant incremental prognostic value and discrimination improvement for all 3 end points. On net reclassification analysis, the addition of LVEF resulted in no significant improvement for all-cause death (11.0%; 95% CI, -6.2% to 25.9%), cardiac death (9.8%; 95% CI, -5.7% to 29.3%), or SCD (7.5%; 95% CI, -41.2% to 42.9%). Conversely, the addition of scar extent resulted in significant reclassification improvement of 25.5% (95% CI, 11.7% to 41.0%) for all-cause death, 27.0% (95% CI, 11.6% to 45.2%) for cardiac death, and 40.6% (95% CI, 10.5% to 71.8%) for SCD. Myocardial scar and LVEF are both risk markers for all-cause and cardiac death in patients with nonischemic cardiomyopathy. However, whereas myocardial scar has strong and incremental prognostic value for SCD risk stratification, LVEF has no incremental prognostic value over clinical measures. Scar assessment should be incorporated into patient selection criteria for primary prevention implantable cardioverter-defibrillator placement.

Abstract 16519: Meta-analysis of Outcome After Implantable Cardioverter Defibrillator Therapy in Patients With Cardiac Amyloidosis

Introduction: Cardiac amyloidosis is associated with high risk for sudden cardiac death. However, the potential benefit of implantable cardioverter defibrillator (ICD) implantation in CA is unknown due to limited available data regarding outcomes following ICD implantation in this patient population. We sought to perform a meta-analysis of trials that evaluated the outcomes of ICD implantation in CA. Methods: We performed a systematic literature review in PubMed, SCOPUS, and Cochrane to identify all studies that evaluated ICD therapy in CA until May 2020. Outcomes analyzed were all-cause mortality and appropriate ICD therapy rates. A random effects model was used to calculate percentages and 95% confidence intervals (CI) of outcomes. Results: Of the screened articles, 5 observational studies were included for analysis. A total of 151 patients were analyzed. Mean age of population was 61.6 +/- 0.7 years and 79.2% were male. The all-cause mortality rate was 33% (95% CI:16 to 51%) and the incidence of appropriate ICD therapy was 23% (95% CI:16 to 30%) over a mean follow up period of 16 months (Figure). In trials that evaluated ICD therapy in non-ischemic cardiomyopathy such as DANISH, DEFINITE and SCD-HeFT trials mortality rates in the ICD arm were 21.6 % over 67.6 months, 9.4% over 29 months and 16.7% over 45.5 months, respectively. The incidence of appropriate therapy in DANISH, DEFINITE and SCD-HeFT trials were 28.9%, 19.8 % and 21% respectively. Conclusions: CA patients with ICD have equivalent appropriate therapy with disproportionately higher mortality over a shorter follow up compared to randomized trials of primary prevention ICD placement in NICMP. The benefit of ICD placement for mortality reduction in CA remains unclear and further large-scale studies are required to address this issue.

Value of CMR and PET in Predicting Ventricular Arrhythmias in Ischemic Cardiomyopathy Patients Eligible for ICD

ObjectivesThis study presents a head-to-head comparison of the value of cardiac magnetic resonance (CMR)-derived left-ventricular (LV) function and scar burden and positron emission tomography (PET)-derived perfusion and innervation in predicting ventricular arrhythmias (VAs). BackgroundImproved risk stratification of VA is important to identify patients who should benefit of prophylactic implantable cardioverter-defibrillator (ICD) implantation. Perfusion abnormalities, sympathetic denervation, and scar burden have all been linked to VA, although comparative studies are lacking. MethodsSeventy-four patients with ischemic cardiomyopathy and left-ventricular ejection fraction (LVEF) ≤35%, referred for primary prevention ICD placement were enrolled prospectively. Late gadolinium-enhanced (LGE) CMR was performed to assess LV function and scar characteristics. [15O]H2O and [11C]hydroxyephedrine positron emission tomography (PET) were performed to quantify resting and hyperemic myocardial blood flow (MBF), coronary flow reserve (CFR), and sympathetic innervation. During follow-up of 5.4 ± 1.9 years, the occurrence of sustained VA, appropriate ICD therapy, and mortality were evaluated. ResultsIn total, 20 (26%) patients experienced VA. CMR and PET parameters showed considerable overlap between patients with VA and patients without VA, caused by substantial heterogeneity within groups. Univariable analyses showed that lower LVEF (hazard ratio [HR]: 0.92; p = 0.03), higher left-ventricular end-diastolic volume index (LVEDVi) (HR 1.02; p < 0.01), and larger scar border zone (HR 1.11; p = 0.03) were related to VA. Scar core size, resting MBF, hyperemic MBF, perfusion defect size, innervation defect size, and the innervation-perfusion mismatch were not found to be associated with VA. ConclusionsIn patients with ischemic cardiomyopathy, lower LVEF, higher LVEDVi, and larger scar border zone were related to VA. PET-derived perfusion and sympathetic innervation, as well as CMR-derived scar core size were not associated with VA. These results suggest that improved prediction of VA by advanced imaging remains challenging for the individual patient.

Automatic implantable cardioverter defibrillator: when not to implant.

The implantable cardioverter-defibrillator (ICD) is the mainstay therapy for primary prevention of sudden cardiac death in patients with heart failure with a reduced ejection fraction. Current indications for prophylactic ICD are based on the results of randomized controlled trials dating back to 15-20 years ago, which have usually enrolled highly selected patients with few comorbidities and only a small number of patients aged >75 years. Existing literature suggest an age-dependent attenuation of the efficacy of the ICD. Because of the ageing of the population, there is need for data addressing device efficacy among older patients that also considers the impact of geriatric syndromes on health status. The assessment of frailty may be of value in identifying elderly patients who may or may not benefit from ICD placement for primary prevention of sudden cardiac death.

Frailty, Implantable Cardioverter Defibrillators, and Mortality: a Systematic Review.

Evidence for the benefit of implantable cardioverter defibrillators (ICD) in preventing sudden cardiac death (SCD) in older adults is mixed; age alone may not predict benefit. Frailty may help identify patients in whom an ICD does not improve overall mortality risk. Structured search of PubMed, Embase, Web of Science, and Cochrane Central Register of Controlled Trials on 1/31/2019, without language restriction, with terms for ICD, frailty, and mortality. Frailty was defined broadly using any validated single component (e.g., walking speed, weight loss) or multi-component tool (e.g., cumulative deficit index). Each study was assessed for quality and risk of bias. We identified and screened 2649 titles, reviewed 280 abstracts, and extracted 71 articles. Nine articles, including two RCTs, one prospective cohort, and six retrospective cohort studies met all criteria. The most common reason for exclusion was a lack of frailty definition. Frailty definitions were heterogeneous, including cumulative deficit models, low weight, and walking speed. Follow-up time for mortality differed: from days to > 6years. All studies indicated that mortality was higher amongst individuals identified as frail, regardless of definition. In one RCT, slow walkers did not benefit from ICD therapy after 3years. A cohort of 83,792 Medicare beneficiaries in an ICD registry reported higher 1-year mortality following ICD in those with frailty or dementia. Four studies reported an association between being underweight and increased mortality following ICD placement. Existing literature suggests that individuals with frailty may not benefit from ICD placement for primary prevention of SCD.

Is Time From Last Hospitalization for Heart Failure to Placement of a Primary Prevention Implantable Cardioverter-Defibrillator Associated With Patient Outcomes?

Landmark studies have demonstrated the safety and efficacy of implantable cardioverter-defibrillators (ICDs) in selected stable ambulatory patients with heart failure (HF) with a reduced ejection fraction receiving optimal medical therapy. It is not known whether a recent hospitalization for HF before ICD placement is associated with subsequent outcomes. A post hoc analysis was performed of Medicare beneficiaries enrolled in the National Cardiovascular Data Registry's ICD Registry with a known diagnosis of HF and an ejection fraction ≤35% underdoing a new ICD placement for primary prevention. Patients were grouped based on the timing of ICD placement from the last hospitalization for HF. The association between timing of ICD placement and outcomes was assessed by using multivariable logistic regression models. The final analytic cohort included 81 180 patients undergoing initial ICD placement for primary prevention who were currently hospitalized for HF (n=11 563, 14%), hospitalized for HF within 3 months (n=6252, 8%), or hospitalized for HF >3 months previously or had no previous hospitalizations for HF (n=63 365, 78%). Patients currently or recently hospitalized for HF had a higher unadjusted composite periprocedural complication rate (2.60% versus 1.71% versus 1.25%, P<0.001). After adjusting for potential confounders, patients currently hospitalized for HF were at higher risk for death (odds ratio, 2.25; 95% CI, 2.02-2.52; P <0.001) and all-cause readmission (odds ratio, 1.89; 95% CI, 1.79-1.99; P <0.001) at 90 days. Older patients currently or recently hospitalized for HF undergoing initial ICD placement for primary prevention experienced a higher rate of periprocedural complications and were at increased risk of death in comparison with those receiving an ICD without recent HF hospitalization. Additional prospective, real-world, pragmatic, comparative effectiveness studies should be conducted to define the optimal timing of ICD placement.

Moving Beyond the Hospital.

Moving Beyond the Hospital.

Implantable Cardioverter-Defibrillator Placement for Primary Prevention in 2,346 Patients: Predictors of One-Year Survival.

Guidelines suggest that patients who receive implantable cardioverter-defibrillators (ICDs) for primary prevention should be expected to live more than one year after placement. However, tools for validating this prognosis are not sufficiently predictive. We sought to identify definitive predictors of one-year survival after ICD placement. By reviewing medical records and the Social Security Death Index, we analyzed baseline characteristics and survival outcomes of 3,164 patients who underwent ICD placement at our institution from January 2006 through March 2014. Survival outcome could be confirmed for 2,346 patients (74%). Of these, 184 (7.8%) died within one year of ICD placement. We noted significant differences in numerous variables between those who lived and died. However, multivariable analysis revealed only 5 independent predictors of earlier death: worse New York Heart Association functional class (hazard ratio [HR]=1.87 per class [95% CI, 1.22-2.87]; P <0.01); lower serum sodium level (HR=0.93 per 1 mEq/L increase [95% CI, 0.88-0.99]; P=0.04); atrial fibrillation (HR=1.81 [95% CI, 1.03-3.21]; P=0.04); chronic lung disease (HR=2.05 [95% CI, 1.20-3.51]; P <0.01), and amiodarone use (HR=10.1 [95% CI, 4.51-22.5]; P <0.01). Using receiver operating characteristic curves, we developed a model with an area under the curve of 0.718 that predicted death at one year after ICD implantation. Despite significant univariate differences between the ICD recipients who did and did not live beyond one year, we found only moderate predictors of survival. Better tools are needed to predict outcomes when considering ICD placement for primary prevention.

The wearable defibrillator: current technology, indications and future directions.

The wearable cardioverter-defibrillator has been available for over a decade. In recent years, the device has been prescribed increasingly for a wide range of indications. The purpose of this review is to describe the technical and clinical aspects of the wearable cardioverter-defibrillator. The available literature on safety, efficacy and cost-effectiveness is reviewed, and indications for use will be discussed. The wearable cardioverter-defibrillator has been used successfully in more than 100 000 patients for a variety of indications. These include high-risk patients after myocardial infarction or revascularization or with heart failure and newly diagnosed cardiomyopathy. It has also been used to bridge the time period of postponed implantable cardioverter-defibrillator implantation or reimplantation, or until heart transplantation. It has been shown that the device safely and effectively terminates ventricular tachycardia and fibrillation with high first shock success. Patient compliance has been high. Although no randomized trial has been published yet, several guidelines recommend wearable cardioverter-defibrillator use in different patient populations and clinical scenarios. The wearable cardioverter-defibrillator effectively bridges a limited time period in patients with a real or perceived high risk for sudden cardiac arrest and may become a helpful tool for risk stratification to better select patients for primary prevention implantable cardioverter-defibrillator placement.

Outcomes After Implantable Cardioverter-Defibrillator Generator Replacement for Primary Prevention of Sudden Cardiac Death.

The effectiveness of implantable cardioverter-defibrillators (ICDs) for primary prevention of sudden death in patients with an ejection fraction (EF) ≤ 35% and clinical heart failure is well established. However, outcomes after replacement of the ICD generator in patients with recovery of EF to >35% and no previous therapies are not well characterized. Between 2001 and 2011, generator replacement was performed at 2 tertiary medical centers in 253 patients (mean age, 68.3 ± 12.7 years; 82% men) who had previously undergone ICD placement for primary prevention but subsequently never received appropriate ICD therapy. EF had recovered to > 35% in 72 of 253 (28%) patients at generator replacement. During median (quartiles) follow-up of 3.3 (1.8-5.3) years after generator replacement, 68 of 253 (27%) experienced appropriate ICD therapy. Patients with EF ≤ 35% were more likely to experience ICD therapy compared with those with EF > 35% (12% versus 5% per year; hazard ratio, 3.57; P = 0.001). On multivariable analysis, low EF predicted appropriate ICD therapy after generator replacement (hazard ratio, 1.96 [1.35-2.87] per 10% decrement; P = 0.001). Death occurred in 25% of patients 5 years after generator replacement. Mortality was similar in patients with EF ≤ 35% and > 35% (7% versus 5% per year; hazard ratio, 1.10; P = 0.68). Atrial fibrillation (3.24 [1.63-6.43]; P < 0.001) and higher blood urea nitrogen (1.28 [1.14-1.45] per increase of 10 mg/dL; P < 0.001) were associated with mortality. Although approximately one fourth of patients with a primary prevention ICD and no previous therapy have EF >35% at the time of generator replacement, these patients continue to be at significant risk for appropriate ICD therapy (5% per year). These data may inform decisions on ICD replacement.

Use of Guideline-Directed Medications for Heart Failure Before Cardioverter-Defibrillator Implantation

BackgroundGuideline-directed medical therapy (GDMT) for heart failure with reduced ejection fraction (HFrEF) is recommended before primary prevention implantable cardioverter-defibrillator (ICD) placement. Adherence to this recommendation and associated outcomes are unknown. ObjectivesThis study examined the use of GDMT (≥1 prescription filled for both a renin-angiotensin inhibitor [RAI] and a heart failure–approved beta-blocker [HFBB]) within 90 days before primary prevention ICD placement in patients with HFrEF. MethodsData from the National Cardiovascular Data Registry ICD Registry were merged with a 40% random sample of Medicare administrative data. Prescription fills for recipients of primary prevention ICD between 2007 and 2011 were examined, analyzing GDMT overall and for each U.S. hospital referral region. We identified characteristics associated with GDMT and the association with 1-year mortality. ResultsAmong 19,733 patients with HFrEF and primary prevention ICD, 61.1% filled any GDMT before implantation. Across hospital referral regions, GDMT was applied in 51% to 71%. The strongest predictors of any GDMT included absence of chronic renal disease or nonsustained ventricular tachycardia, low-income prescription benefits subsidy, and less recent left ventricular ejection fraction evaluation. Patients receiving GDMT versus those without had a lower 1-year mortality rate after ICD implantation (11.1% vs. 16.2%), even after adjustment for comorbidities, left ventricular ejection fraction, and functional heart failure class. ConclusionsRates of GDMT for HFrEF before primary prevention ICD implantation were low, and failure to achieve GDMT was associated with significantly decreased 1-year survival.

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.

Circulation : Clinical Summaries

<i>Circulation</i> : Clinical Summaries

Survival after primary prevention implantable cardioverter-defibrillator placement among patients with chronic kidney disease.

Guidelines recommend that implantable cardioverter-defibrillator (ICD) candidates have an estimated longevity of ≥1 year. Longevity can be affected by chronic kidney disease (CKD). Using the National Cardiovascular Data Registry ICD registry linked with the Social Security Death Master File, we assessed the rate of death after primary prevention ICD placement between January 1, 2006, and December 31, 2007, according to CKD stage. Using Cox models, we identified factors associated with death among patients with CKD. Compared with patients without CKD (n=26,056), those with CKD (n=21,226) were older, less commonly men, more often white, and more frequently had comorbid illness. Compared with patients without CKD, patients with a glomerular filtration rate 30 to 60, glomerular filtration rate <30, and end-stage renal disease on dialysis had a higher risk of death after ICD placement (hazard ratio, 2.08; 95% confidence interval, 1.99-2.18; P<0.0001; hazard ratio, 4.20; 95% confidence interval, 3.92-4.50; P<0.0001; and hazard ratio, 4.80; 95% confidence interval, 4.46-5.17; P<0.0001, respectively). Corresponding 1-year death rates were 4.4%, 9.1%, 20.2%, and 22.4%. Among patients with CKD, factors associated with increased risk of death included CKD severity, age >65 years, heart failure symptoms, diabetes mellitus, lung disease, serum sodium <140 mEq/L, atrial fibrillation or flutter, and a lower ejection fraction. The risk of death after primary prevention ICD placement is proportional to CKD severity. Among patients with CKD, several factors are prognostically significant and could inform clinical decision making on primary prevention ICD candidacy.

Abstract 91: 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 NCDR ®

Background: Trends in the use and outcomes of ICDs in community practice settings are not well characterized. Our objective was to determine the temporal trends in characteristics and outcomes among patients undergoing primary prevention ICD therapy. Methods: We identified Medicare beneficiaries aged 65 years and older with an ejection fraction &lt;35% undergoing ICD implantation for primary prevention between 2006 and 2010 in the NCDR ICD Registry™. Using a probabilistic method, eligible subjects were matched to Medicare claims data to capture outcomes using age, gender, admission date or procedure date, and hospital Medicare provider number. We tested the significance of trends in characteristics over time with χ2 tests for categorical variables and ANOVA for continuous variables. Standardized outcome rates were calculated adjusting for demographics and characteristics. Results: A total of 117,100 patients were included in the analysis. Between 2006 and 2010, small but significant increases were observed in the prevalence of hypertension, diabetes, and NYHA Class III symptoms, and decreases in the prevalence of ischemic heart disease and NYHA Class IV symptoms (Table 1). There was minimal change in age, gender, and race of patients receiving ICDs over the study period; fewer single lead and more biventricular devices were used over time. Risk-standardized six-month re-hospitalization and complication rates decreased and risk-standardized six-month all-cause mortality was stable over the study period (Table 1). Conclusions: Modest changes in patient characteristics undergoing primary prevention ICD implantation were observed between 2006 and 2010. There have simultaneously been significant improvements in outcomes after accounting for these patient trends, suggesting the possibility that there have been improvements in care of this patient population.