Implantable Cardioverter Defibrillator Recipients Research Articles

Impact of a Chronic Total Coronary Occlusion on the Incidence of Appropriate Implantable Cardioverter-Defibrillator Shocks and Mortality: A Substudy of the Dutch Outcome in ICD Therapy (DO-IT)) Registry.

Chronic total coronary occlusions (CTO) substantially increase the risk for sudden cardiac death. Among patients with chronic ischemic heart disease at risk for sudden cardiac death, an implantable cardioverter defibrillator (ICD) is the favored therapy for primary prevention of sudden cardiac death. This study sought to investigate the impact of CTOs on the risk for appropriate ICD shocks and mortality within a nationwide prospective cohort. This is a subanalysis of the nationwide Dutch-Outcome in ICD Therapy (DO-IT) registry of primary prevention ICD recipients in The Netherlands between September 2014 and June 2016 (n=1442). We identified patients with chronic ischemic heart disease (n=663) and assessed available coronary angiograms for CTO presence (n=415). Patients with revascularized CTOs were excluded (n=79). The primary end point was the composite of all-cause mortality and appropriate ICD shocks. Clinical follow-up was conducted for at least 2 years. A total of 336 patients were included, with an average age of 67±9 years, and 20.5% was female (n=69). An unrevascularized CTO was identified in 110 patients (32.7%). During a median follow-up period of 27 months (interquartile range, 24-32), the primary end point occurred in 21.1% of patients with CTO (n=23) compared with 11.9% in patients without CTO (n=27; P=0.034). Corrected for baseline characteristics including left ventricular ejection fraction, and the presence of a CTO was an independent predictor for the primary end point (hazard ratio, 1.82 [95% CI, 1.03-3.22]; P=0.038). Within this nationwide prospective registry of primary prevention ICD recipients, the presence of an unrevascularized CTO was an independent predictor for the composite outcome of all-cause mortality and appropriate ICD shocks.

Mortality Benefit Among Primary Prevention Implantable Cardioverter-Defibrillator Recipients on Contemporary Heart Failure Treatment

BackgroundPast clinical trials have shown the benefit of implantable cardioverter-defibrillators (ICDs) for reducing sudden cardiac death in at-risk patients. However, heart failure management and ICD technology have changed since these trials were first published. An updated assessment of ICD mortality benefit is needed. ObjectivesThe purpose of this study was to compare mortality rates between patients with a primary prevention (PP) indication for an ICD who did or did not receive an ICD using a contemporary, real-world data set. MethodsData was obtained from a large electronic health record data set covering patients in the United States from 2012 through 2020 who had a PP indication for an ICD and survived at least 1-year postindication. ResultsA total of 25,296 patients were identified as having a PP indication for ICD implantation, of which 2,118 (8.4%) were treated with an ICD within a year. Treated patients were younger than nontreated patients (age 63.4 years vs 66.1 years) with a smaller proportion of women (25.0% vs 36.7%). After 4-to-1 propensity matching, treated patients had similar clinical characteristics to nontreated patients. A Cox proportional hazard model estimated a 24.3% lower risk of all-cause mortality in patients when treated vs not treated with an ICD (HR: 0.757; 95% CI: 0.678-0.835; P <0.001). There was no detectable difference in ICD benefit between patients with ischemic and nonischemic heart disease (P = 0.50). ConclusionsICD treatment of patients with a PP indication is associated with improved mortality even in the context of evolving adjunctive HF treatment, consistent with earlier landmark trials.

Comparison of novel intrinsic versus conventional antitachycardia pacing for ventricular tachycardia among implantable cardioverter-defibrillator recipients.

Intrinsic antitachycardia pacing (iATP) is a novel automated antitachycardia pacing (ATP) that provides individual treatment to terminate ventricular tachycardia (VT). However, the clinical efficacy of iATP in comparison with conventional ATP is unknown. We aim to compare the termination rate of VT between iATP and conventional ATP in patients with implantable cardioverter-defibrillators using a unique setting of different sequential orders of both ATP algorisms. Patients with the iATP algorithm were assigned to iATP-first and conventional ATP-first groups sequentially. In the iATP-first group, a maximum of seven iATP sequences were delivered, followed by conventional burst and ramp pacing. In contrast, in the conventional ATP-first group, two bursts and ramp pacing were initially programmed, followed by iATP sequences. We compared the success rates of VT termination in the first and secondary programmed ATP zones between the two groups. Fifty-eight and 56 patients were enrolled in the iATP-first and conventional ATP-first groups, and 67 and 44 VTs were analyzed in each group, respectively. At the first single ATP therapy, success rates were 64% and 70% in the iATP and conventional groups, respectively. At the end of the first iATP treatment zone, the success rate increased from 64% to 85%. Moreover, secondary iATP therapy following the failure of conventional ATPs increased the success rate from 80% to 93%. There was a significant benefit of alternative iATP for VT termination compared to secondary conventional ATP (100% vs. 33%, p = .028). iATP may be beneficial as a secondary therapy after failure of conventional ATP to terminate VT.

Differences in underlying cardiac substrate among S-ICD recipients and its impact on long-term device-related outcomes: Real-world insights from the iSUSI registry

BackgroundOutcome comparisons among subcutaneous implantable cardioverter-defibrillator (S-ICD) recipients with nonischemic cardiomyopathies are scarce. ObjectiveThe aim of this study was to evaluate differences in device-related outcomes among S-ICD recipients with different structural substrates. MethodsPatients enrolled in the i-SUSI (International SUbcutaneouS Implantable cardioverter defibrillator registry) project were grouped according to the underlying substrate (ischemic vs nonischemic) and subgrouped into dilated cardiomyopathy, hypertrophic cardiomyopathy, Brugada syndrome (BrS), arrhythmogenic right ventricular cardiomyopathy (ARVC). The main outcome of our study was to compare the rates of appropriate and inappropriate shocks and device-related complications. ResultsAmong 1698 patients, the most common underlying substrate was ischemic (31.7%), followed by dilated cardiomyopathy (20.5%), BrS (10.8%), hypertrophic cardiomyopathy (8.5%), and ARVC (4.4%). S-ICD for primary prevention was more common in the nonischemic cohort (70.9% vs 65.4%; P = .037). Over a median (interquartile range) follow-up of 26.5 (12.6–42.8) months, no differences were observed in appropriate shocks between ischemic and nonischemic patients (4.8%/y vs 3.9%/y; log-rank, P = .282). ARVC (9.0%/y; hazard ratio [HR] 2.492; P = .001) and BrS (1.8%/y; HR 0.396; P = .008) constituted the groups with the highest and lowest rates of appropriate shocks, respectively. Device-related complications did not differ between groups (ischemic: 6.4%/y vs nonischemic: 6.1%/y; log-rank, P = .666), nor among underlying substrates (log-rank, P = .089). Nonischemic patients experienced higher rates of inappropriate shocks than did ischemic S-ICD recipients (4.4%/y vs 3.0%/y; log-rank, P = .043), with patients with ARVC (9.9%/y; P = .001) having the highest risk, even after controlling for confounders (adjusted HR 2.243; confidence interval 1.338–4.267; P = .002). ConclusionMost S-ICD recipients were primary prevention nonischemic cardiomyopathy patients. Among those, patients with ARVC tend to receive the most frequent appropriate and inappropriate shocks and patients with BrS the least frequent appropriate shocks.

Factors Associated With Non-Uptake of Implantable Cardioverter-Defibrillator (ICD) Among Eligible Patients at a Tertiary Hospital in Kenya.

Efficacy of Implantable Cardioverter-Defibrillator (ICD) implantation in both primary and secondary prevention of Sudden Cardiac Death (SCD) in at-risk population is well established. ICD implantation rates remain low particularly in Africa with a paucity of data regarding factors associated with non-uptake. The primary study objective was to determine the factors associated with non-uptake of ICD among heart failure (HF) patients with reduced ejection fraction (EF<35%). Reasons for ICD refusal among eligible patients were reviewed as a secondary objective. This was a retrospective study among HF patients eligible for ICD implantation evaluated between 2018 to 2020. Comparison between ICD recipient and non-recipient categories was made to establish determinants of non-uptake. Of 206 eligible patients, only 69 (33.5%) had an ICD. Factors independently associated with non-uptake were lack of private insurance (42.3% vs 63.8%; p = 0.005), non-cardiology physician (16.1% vs 5.8%; p = 0.045) and non-ischemic cardiomyopathy (54.7% vs 36.4% p = 0.014). The most common (75%) reason for ICD refusal was inability to pay for the device. ICDs are underutilized among eligible HF with reduced EF patients in Kenya. The majority of patients without ICD had no private insurance, had non-ischemic cardiomyopathy and non-cardiology primary physician. Early referral of HF with reduced EF patients to HF specialists to optimize guideline-directed medical therapy and make ICD recommendation is needed.

Association of Device-Detected Atrial High-Rate Episodes With Long-term Cardiovascular and All-Cause Mortality: A Cohort Study

BackgroundDevice-detected atrial high-rate episodes (AHREs) were associated with an increased thromboembolic risk. Although limited data regarding the long-term prognosis of patients with AHRE were controversial, this study aimed to identify the association of device-detected AHRE with mortality. MethodsThis observational study included patients with implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D) placement and no history of atrial fibrillation (AF), atrial flutter (AFL), or atrial tachycardia (AT). During follow-up, patients with at least 1 day of AHRE duration ≥ 15 minutes were identified. The primary endpoint was cardiovascular mortality, and the secondary endpoint was all-cause mortality. ResultsDuring a mean follow-up period of 4.2 years, AHREs were detected in 124 of 343 (36.2%) patients. Of these, 44 deaths (35.5%) occurred in 124 patients with AHREs, which was significantly higher than those without AHREs (43 of 219; 19.6%; P = 0.001). The multivariate analysis revealed that patients with AHRE had a significantly higher risk of cardiovascular (hazard ratio [HR], 2.40; 95% confidence interval [CI], 1.23-4.67; P = 0.010), and all-cause mortality (HR, 2.31; 95% CI, 1.49-3.59; P < 0.001). Further analysis indicated that this association remained significant in patients with higher burden (≥ 6 hours) but not in patients with lower burden (≥ 15 minutes to 6 hours). Notably, even after excluding the patients diagnosed with clinical AF during follow-up, the remaining patients with AHREs still exhibited a higher risk of cardiovascular and all-cause mortality compared with patients without AHREs. ConclusionsAHREs were prevalent in ICD or CRT-D recipients with no history of clinical AF, AFL, or AT and were associated with more than twice the risk of cardiovascular and all-cause mortality. Clinical Trial RegistrationNo. ChiCTR-ONRC-13003695.

Changes in medical therapy after cardiac resynchronization in patients with heart failure: insights from the U.S. Veterans Affairs healthcare system

Abstract Background Patients with heart failure with reduced ejection fraction (HFrEF) are often not treated with comprehensive guideline directed medical therapy (GDMT) due to hemodynamic and renal limitations. Cardiac resynchronization therapy (CRT) improves hemodynamics in patients with HFrEF and ventricular dyssynchrony. Whether CRT facilitates intensification of GDMT in patients with HFrEF has not been well-studied. Purpose To assess pre-procedure GDMT (B-blocker, ACEI [angiotensin converting enzyme inhibitor]/ARB [angiotensin receptor blocker], ARNI [angiotensin receptor neprilysin inhibitor], MRA [mineralocorticoid receptor antagonist], SGLT2i [sodium-glucose cotransporter-2 inhibitor]) utilization in HFrEF patients who received CRT and to compare changes in GDMT in patients who received CRT with patients who received implantable cardioverter-defibrillator (ICD). Methods Veterans with left ventricular ejection fraction (LVEF) 35% who received CRT or ICD from Feb 22, 2000 – Jul 28, 2022 were identified. Patients with end-stage renal disease were excluded. Changes in GDMT 12-months following device implant were characterized and compared between CRT and ICD recipients. Mixed effects logistic regression models were generated to evaluate associations between receipt of CRT and the composite of therapy initiation, dose increase, or target dose achievement compared with ICD. Models were adjusted for clinical characteristics and pre-implant GDMT utilization. Similar models were developed to evaluate the adjusted associations between CRT and changes in estimated glomerular filtration rate (eGFR) and blood pressure (BP) compared with ICD. Results A total of 2,082 CRT recipients and 7,263 ICD recipients were identified. Pre-procedure heart rate, BP, serum potassium, and eGFR were within normal ranges and similar between groups. Prior to device implant, ACEI/ARB/ARNI were most frequently prescribed (91%), followed by -blockers (88%), MRA (46%), and SGLT2i (33% in post-SGLT2i era). Pre-procedure GDMT was similar between CRT and ICD recipients. At 12 months follow-up, CRT was independently associated with increased odds of therapy initiation, dose increase, or target dose achievement for ACEI/ARB/ARNI, ARNI, B-blockers, and MRA (Figure 1). ICD was associated with a decline in eGFR while CRT was associated with an increase in eGFR (mean [standard deviation]: -0.95 [0.17] vs. +0.6 [0.29]; p&amp;lt;0.01), while no differences were observed in BP or LVEF at 12 months. Conclusions In a large, contemporary cohort of patients with HFrEF, most patients were not prescribed MRA or SGLT2i prior to receiving CRT or ICD despite no apparent renal or blood pressure-related contraindications. CRT is associated with increased odds of the composite of initiation, dose increase, or target dose achievement for ACEI/ARB/ARNI, ARNI, B-blockers, and MRA compared with ICD. GDMT intensification may be mediated by beneficial changes in kidney function in CRT recipients.Figure 1

Temporal trends in baseline characteristics of implantable cardioverter defibrillator recipients for primary prevention of sudden cardiac death- The DAIPP program

Abstract Introduction Since expanding the indication for implantable cardioverter defibrillators (ICD) to primary prevention, the patient population of ICD carriers continues to evolve over time. In pursuit of progressively decreasing the burden of sudden cardiac death, improved patient selection and risk-benefit assessment demand, among others, awareness of these temporal changes in clinical baseline characteristics of the ICD population. Purpose The aim was to explore the temporal differences in baseline characteristics of ICD recipients implanted for primary prevention of sudden cardiac death (SCD), and perioperative complications, to improve understanding of ICD population selection over the last two decades in a real-world setting. Methods The Primary Prevention ICD French Registry (DAI-PP program) was initiated in 2002 with an overall aim to assess the risk-benefit ratio of the introduction of ICD for primary prevention over a 20-year period, including a pilot evaluation that finished in 2012. The pilot study laid ground for the ongoing prospective DAIPP Consortium that started in 2018 and is aiming to follow 10000 patients under remote monitoring, using a specific integrational research platform. The two cohorts are in this study compared with regards to baseline characteristics as well as perioperative outcomes, i.e., early mortality and procedural complications. Results This study included 8432 participants, 5521 from the pilot study and 2211 from the prospective trial, with a median follow up of 2.36 (IQR 1.25-3.75) years. Median age was 64 (IQR 56-71) years, 17% female and 61% had ischemic heart disease. Baseline characteristics that remained stable over time were age, cancer burden. Compared to the 2002-2012 period, recent findings found a significant increase in the proportion of females (15 vs 20%, p &amp;lt;0.001), pauci-symptomatic patients (New York Heart Association Functional class-NYHA II, 41 vs. 57%, p &amp;lt;0.001), narrow QRS patients (31 vs. 43%, p&amp;lt;0.001), use of subcutaneous ICD (0 vs. 14%, P&amp;lt;0.001) and more comorbidities including an increase in diabetes, and slight increase in stroke. Regarding pharmacological treatment, there was an increase in use of 2 or 3 medications (2: 6.5% to 16% p&amp;lt;0.001; 3: 20% to 33%, p&amp;lt;0.001) where more received beta blockers and amiodarone in the contemporary study. Perioperative complications decreased over time (13% to 7.9% p&amp;lt;0.001) with a decrease in early reinterventions (1.3% to 0.1% p&amp;lt;0.001) and discrete fall in number of infections (0.7% to 0.1%, p&amp;lt;0.001) and pocket hematoma (4.4% to 3.0% p&amp;lt;0.001). A slight upward trend in number of lead dislodgements was seen over time (1.3% to 1.7% p&amp;lt;0.001). See Table 1 for perioperative complications. Conclusion The primary prevention ICD population has significantly changed over time. An increase in women, comorbidities, and use of 2-3 medications was seen, coupled with more participants receiving a subcutaneous ICD. Perioperative complications decreased over time.

Cardiac magnetic resonance for prophylactic implantable-cardioVerter defibrillator therapy international registry in patients with ischemic cardiomyopathy

Abstract Background Sudden cardiac death (SCD) in patients with ischemic cardiomyopathy (ICM) remains a leading cause of death. Current guidelines provide a class I recommendation for implantable cardioverter–defibrillator (ICD) implantation in ICM patients with transthoracic echocardiographic (TTE) left ventricular ejection fraction (LVEF) ≤35%. and NYHA functional class II or III. The current paradigm is suboptimal in identifying patients who are likely to benefit. In fact, only a relatively small proportion of ICD recipients for SCD primary prevention receive appropriate device therapy and instead there is a not negligible percentage of patients who experienced SCD event despite not fulfilling criteria for implantation. Purpose The DERIVATE-ICM registry sought to evaluate the additional prognostic value for the indication of ICD implantation using cardiac magnetic resonance (CMR) as compared to standard of care based on TTE in a large cohort of ICM patients. Methods We enrolled 861 ICM patients (86% male, mean age 65±11 years) with chronic heart failure and TTE-LVEF&amp;lt;50%. Major adverse arrhythmic cardiac events (MAACE), defined as the combination of SCD, aborted SCD event, and sustained ventricular tachycardia. were the primary endpoint. Independent predictors were used to calculate a CMR risk score for each patient. Risk levels were defined as low (quantile 1 [Q1]), medium (Q2 and Q3) and high (Q4). Results During a median follow-up of 1054 days, MAACE occurred in 88 (10.2%). Left ventricular end-diastolic volume index (HR:1.007, 95%CI:1.000-1.011, p=0.05), CMR-LVEF (HR:0.972, 95%CI: 0.945-0.999, p=0.045) and late gadolinium enhancement (LGE) mass (HR:1.010, 95%CI: 1.002–1.018, p=0.015) were independent predictors of MAACE. Based on the multivariate analysis, CMR weighted risk score was developed according to the following equation [0.005 * EDV/BSA (mL/m2) – 0.029 * LVEF (%) + 0.010 * LGE ischemic mass (g)]. A multiparametric CMR weighted predictive derived score effectively identifies subjects at high risk for MAACE as compared to TTE-LVEF cut-off of 35% with a Continuous NRI: 31.7% (95%CI: 8.6%-54.8%, p=0.007) (Figure 1, Figure 2). Conclusions In this large multicenter registry, a multi-parametric CMR predictive model provides additional prognostic stratification for MAACE predictions in a large cohort of ICM patients as compared to standard of care. This model identifies a large number of patients with TTE-LVEF&amp;lt;35% at low risk of SCD event and on the other side it identifies a subset of patients who are at high risk of MAACE despite TTE-LVEF≥35% (i.e. the population currently not fulfilling the guideline-based criteria for ICD implantation). Further randomized trials to test a CMR guided strategy for ICD implantation versus standard of care are now needed.Kaplan-Meier curvesEvent rate redistribution

Information provision and follow-up of French patients with implantable cardioverter-defibrillators: The APODEC survey

BackgroundImplantable cardioverter-defibrillators reduce mortality, but the electric shocks delivered can impact the patient's quality of life. Patient education is an efficient way to reduce the stress related to both the device and the disease. AimsWe assessed the evolution of knowledge and satisfaction of implantable cardioverter-defibrillator recipients regarding their cardiac disease, implantable cardioverter-defibrillator implantation, follow-up complications, remote monitoring and daily life recommendations. Quality of life, implantable cardioverter-defibrillator-related stress levels and remote monitoring benefits were also evaluated. MethodsA self-administered questionnaire of 43 items was published on the French Association of Cardiac Electrical Device Wearers (APODEC) website and sent to registered patients. ResultsOverall, 330 patients completed the survey. Physicians were the patients’ principal information source regarding their cardiac disease (86.7%) and implantable cardioverter-defibrillator (93.3%), and 90% looked for further information after the procedure, mainly on websites (78.8%). More than half of the patients were not sufficiently informed about implantable cardioverter-defibrillators before implantation (61.2%). In the patients’ opinion, the best sources of further information were their physician (81.8%), patient associations (63.6%) and the Internet (45.8%). Although patient knowledge increased during follow-up, their knowledge could be improved regarding daily life with an implantable cardioverter-defibrillator (52.1%), remote monitoring (34.2%) and their cardiac disease (32.1%). Remote monitoring follow-up was used by 92.1% of patients and mostly improved their peace of mind (67.8%). Implantable cardioverter-defibrillator shocks were associated with major stress for patients receiving them (46.6%). ConclusionThese findings highlight the lack of information provided to implantable cardioverter-defibrillator recipients before implantation, a concerning issue to be addressed in the near future.

Machine learning-derived cycle length variability metrics predict spontaneously terminating ventricular tachycardia in implantable cardioverter defibrillator recipients.

Implantable cardioverter defibrillator (ICD) therapies have been associated with increased mortality and should be minimized when safe to do so. We hypothesized that machine learning-derived ventricular tachycardia (VT) cycle length (CL) variability metrics could be used to discriminate between sustained and spontaneously terminating VT. In this single-centre retrospective study, we analysed data from 69 VT episodes stored on ICDs from 27 patients (36 spontaneously terminating VT, 33 sustained VT). Several VT CL parameters including heart rate variability metrics were calculated. Additionally, a first order auto-regression model was fitted using the first 10 CLs. Using features derived from the first 10 CLs, a random forest classifier was used to predict VT termination. Sustained VT episodes had more stable CLs. Using data from the first 10 CLs only, there was greater CL variability in the spontaneously terminating episodes (mean of standard deviation of first 10 CLs: 20.1 ± 8.9 vs. 11.5 ± 7.8 ms, P < 0.0001). The auto-regression coefficient was significantly greater in spontaneously terminating episodes (mean auto-regression coefficient 0.39 ± 0.32 vs. 0.14 ± 0.39, P < 0.005). A random forest classifier with six features yielded an accuracy of 0.77 (95% confidence interval 0.67 to 0.87) for prediction of VT termination. Ventricular tachycardia CL variability and instability are associated with spontaneously terminating VT and can be used to predict spontaneous VT termination. Given the harmful effects of unnecessary ICD shocks, this machine learning model could be incorporated into ICD algorithms to defer therapies for episodes of VT that are likely to self-terminate.

QRS complex and T wave planarity for the efficacy prediction of automatic implantable defibrillators

ObjectiveTo test the hypothesis that in recipients of primary prophylactic implantable cardioverter-defibrillators (ICDs), the non-planarity of ECG vector loops predicts (a) deaths despite ICD protection and (b) appropriate ICD shocks.MethodsDigital...

Association between nighttime heart rate and cardiovascular mortality in patients with implantable cardioverter-defibrillator: A cohort study

Although studies have shown that an increased resting heart rate measured randomly at a single point of the day has been associated with adverse cardiovascular outcomes, the utility of continuous monitoring of nighttime heart rate (NTHR) has remained largely uninvestigated. This study aimed to explore the association between NTHR and cardiovascular mortality. The Study of Home Monitoring System Safety and Efficacy in Cardiac Implantable Electronic Device-implanted Patients, which is a prospective cohort study, enrolled patients with implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy defibrillator between 2010 and 2015. Baseline NTHR was measured during the programmed sleep period from 30 to 60 days after implantation. The primary outcome was cardiovascular mortality, fitted by a restricted cubic spline function. A total of 534 implantable cardioverter-defibrillator recipients with sinus rhythm during the detection window were included in the study. The mean baseline NTHR was 59.6 ± 8.0 beats/min. During the follow-up period of 60.4 ± 21.8 months, 88 (16.5%) patients experienced cardiovascular mortality. After considering potential confounders, a linear association was observed. Each 1 beat/min increase in NTHR was associated with a 7.8%, 10.1%, and 5.7% increase in the risk of cardiovascular mortality in the total population, patients with heart failure, and patients without heart failure, respectively. Continuous monitoring of NTHR may identify patients at high risk of cardiovascular mortality in a timely manner, with the potential for "preemptive" action. No. ChiCTR-ONRC-13003695.

Effect of Carvedilol vs Metoprolol on Atrial and Ventricular Arrhythmias Among Implantable Cardioverter-Defibrillator Recipients

BackgroundBoth selective and nonselective beta-blockers are used to treat patients with heart failure (HF). However, the data on the association of beta-blocker type with risk of atrial arrhythmia and ventricular arrhythmia (VA) in HF patients with a primary prevention implantable cardioverter-defibrillator (ICD) are limited. ObjectivesThis study sought to evaluate the effect of metoprolol vs carvedilol on the risk of atrial tachyarrhythmia (ATA) and VA in HF patients with an ICD. MethodsThis study pooled primary prevention ICD recipients from 5 landmark ICD trials (MADIT-II, MADIT-CRT, MADIT-RIT, MADIT-RISK, and RAID). Fine and Gray multivariate regression models, stratified by study, were used to evaluate the risk of ATA, inappropriate ICD shocks, and fast VA (defined as ventricular tachycardia ≥200 beats/min or ventricular fibrillation) by beta-blocker type. ResultsAmong 4,194 patients, 2,920 (70%) were prescribed carvedilol and 1,274 (30%) metoprolol. The cumulative incidence of ATA at 3.5 years was 11% in patients treated with carvedilol vs 15% in patients taking metoprolol (P = 0.003). Multivariate analysis showed that carvedilol treatment was associated with a 35% reduction in the risk of ATA (HR: 0.65; 95% CI: 0.53-0.81; P < 0.001) when compared to metoprolol, and with a corresponding 35% reduction in the risk of inappropriate ICD shocks (HR: 0.65; 95% CI: 0.47-0.89; P = 0.008). Carvedilol vs metoprolol was also associated with a 16% reduction in the risk of fast VA. However, these findings did not reach statistical significance (HR: 0.84; 95% CI: 0.70-1.02; P = 0.085). ConclusionsThese findings suggests that HF patients with ICDs on carvedilol treatment experience a significantly lower risk of ATA and inappropriate ICD shocks when compared to treatment with metoprolol.

Efficacy of a web-based healthcare innovation to advance the quality of life and care of patients with an implantable cardioverter defibrillator (ACQUIRE-ICD): a randomized controlled trial.

Modern clinical management of patients with an implantable cardioverter defibrillator (ICD) largely consists of remote device monitoring, although a subset is at risk of mental health issues post-implantation. We compared a 12-month web-based intervention consisting of goal setting, monitoring of patients' mental health-with a psychological intervention if needed-psychoeducational support from a nurse, and an online patient forum, with usual care on participants' device acceptance 12 months after implantation. This national, multi-site, two-arm, non-blinded, randomized, controlled, superiority trial enrolled 478 first-time ICD recipients from all 6 implantation centres in Denmark. The primary endpoint was patient device acceptance measured by the Florida Patient Acceptance Survey (FPAS; general score range = 0-100, with higher scores indicating higher device acceptance) 12 months after implantation. Secondary endpoints included symptoms of depression and anxiety. The primary endpoint of device acceptance was not different between groups at 12 months [B = -2.67, 95% confidence interval (CI) (-5.62, 0.29), P = 0.08]. Furthermore, the secondary endpoint analyses showed no significant treatment effect on either depressive [B = -0.49, 95% CI (-1.19; 0.21), P = 0.17] or anxiety symptoms [B = -0.39, 95% CI (-0.96; 0.18), P = 0.18]. The web-based intervention as supplement to usual care did not improve patient device acceptance nor symptoms of anxiety and depression compared with usual care. This specific web-based intervention thus cannot be recommended as a standardized intervention in ICD patients.

Body image concerns in patients with an implantable cardioverter defibrillator: associations with other patient-reported outcomes

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction Implantation with an implantable cardioverter defibrillator (ICD) is for some patients associated with body image concerns (BICs). The associations of BICs with other patient-reported outcomes (PROs) have not yet been investigated. Purpose The purpose of this study was to investigate the associations between BICs and other PROs in a cohort of ICD-recipients. Methods A cross-sectional survey design was used. Patients who had the ICD in minimum 3 months up to 2 years, age &amp;gt;18 years, implanted with a first-time ICD (both VVI-ICD, DDD-ICD and CRT-D) completed the 39-item ICD Body Image Concerns Questionnaire (ICD-BICQ) together with the Generalized Anxiety Disorder scale (GAD-7), Patient Health Questionnaire (PHQ-9), Type D Scale (DS14) and the Florida Patient Acceptance Survey (FPAS). Data were analyzed using linear regression to compare personality constructs between patients with and without BICs. Logistic repression and Reciever Operating Characteristic (ROC) curves were used to predict patients with BICs based on other PROs. Results In total 331 patients completed the ICD-BICQ and other PRO questionnaires. Five patients were excluded due to re-operations, and one patient did not complete the ICD-BICQ, leaving 325 patients in the analyses. As anticipated 20% of patients reported body image concerns with a cut-off at the recommended 36 points. We found that patients with BICs reported higher anxiety and depression levels, lower device acceptance using the FPAS, and lower health status, while they were more likely to have a Type D personality as compared to patients without BICs. We observed that FPAS was moderately able to predict BICs, while other PROs only had limited ability to predict BICs in patients, hence indicating that the ICD-BICQ provides relevant clinical information. Conclusion(s) In this study, we found that patients with BICs generally reported worse PRO scores. The included PRO instruments were not able to predict BICs the ICD recipients, hence in clinical practice, health care professionals can use the ICD-BICQ to identify and obtain a nuanced picture of patients with BICs. In case of implementing new operation techniques, the ICD-BICQ can be used as a tool for evaluation.

Effect of myocardial scar size on the risk of ventricular arrhythmias in patients with chronic total coronary occlusion

BackgroundThe presence of an untreated chronic total coronary occlusion (CTO) is associated with a higher risk of ventricular arrhythmias (VAs). This increased risk may be modulated by the presence of an existing scar. ObjectivesTo evaluate whether scar size is associated with VA in patients with an implantable cardioverter-defibrillator (ICD) and a CTO. MethodsIn this retrospective study we included patients with a CTO that received an ICD between 2005 and 2015. Scar size was estimated using the Selvester QRS score on a baseline 12‑lead ECG. The primary endpoint was any appropriate ICD therapy. ResultsOur study population comprised 148 CTO patients with a median scar size at baseline of 18% (IQR, 9–27%). Patients with a scar size ≥18% more often had a CTO located in the left anterior descending artery and a higher proportion of poor left ventricular function (<35%) and infarct-related CTO compared to patients with a smaller scar size (<18%). During a median follow-up of 35 months (interquartile range [IQR], 8–60 months), 42 patients (28%) received appropriate ICD therapy. The cumulative 5-year event rate was higher in the patients with a large scar in comparison to those with a smaller or no scar (36% versus 19%, P = 0.04). Multivariable Cox regression analysis demonstrated that large scar and diabetes mellitus were independent factors associated with appropriate ICD therapy. ConclusionIn ICD recipients with an untreated CTO, a larger scar is an independent factor associated with an increased risk of VA.

Arrhythmia and Survival Outcomes Among Black Patients and White Patients With a Primary Prevention Defibrillator.

Black Americans have a higher risk of nonischemic cardiomyopathy (NICM) than White Americans. We aimed to evaluate differences in the risk of tachyarrhythmias among patients with an implantable cardioverter-defibrillator (ICD). The study population comprised 3895 ICD recipients in the United States enrolled in primary prevention ICD trials. Outcome measures included ventricular tachyarrhythmia (VTA), atrial tachyarrhythmia (ATA), ICD therapies, VTA burden (using Andersen-Gill recurrent event analysis), death, and the predicted benefit of the ICD. All events were adjudicated blindly. Outcomes were compared between self-reported Black patients versus White patients with cardiomyopathy (ischemic and NICM). Black patients were more likely to be female (35% versus 22%) and younger (57±12 versus 62±12 years) with a higher frequency of comorbidities. In NICM, Black patients had a higher rate of first VTA, fast VTA, ATA, and appropriate and inappropriate ICD therapy (VTA ≥170 bpm, 32% versus 20%; VTA ≥200 bpm, 22% versus 14%; ATA, 25% versus 12%; appropriate therapy, 30% versus 20%; and inappropriate therapy, 25% versus 11%; P<0.001 for all). Multivariable analysis showed that Black patients with NICM experienced a higher risk of all types of arrhythmia or ICD therapy (VTA ≥170 bpm, hazard ratio [HR] 1.71; VTA ≥200 bpm, HR 1.58; ATA, HR 1.87; appropriate therapy, HR 1.62; inappropriate therapy, HR 1.86; P≤0.01 for all), higher burden of tachyarrhythmias or therapies (VTA, HR 1.84; appropriate therapy, HR 1.84; P<0.001 for both), and a higher risk of death (HR 1.92; P=0.014). In contrast, in ischemic cardiomyopathy, the risk of all types of tachyarrhythmia, ICD therapy, or death was similar between Black patients and White patients. Both Black patients and White patients derived a significant and similar benefit from ICD implantation. Among patients with NICM with an ICD for primary prevention, Black patients compared with White patients had a high risk and burden of VTA, ATA, and ICD therapies with a lower survival rate. Nevertheless, the overall benefit of the ICD was maintained and was similar to that of White patients.

Appropriate Implantable Cardioverter-Defibrillator Therapy in Patients with Ventricular Arrhythmia of Unclear Cause in Secondary Prevention of Sudden Cardiac Death.

In this study, we sought to investigate the occurrence of appropriate implantable cardioverter-defibrillator (ICD) therapies and inappropriate shocks in secondary prevention ICD recipients with ventricular arrhythmia of unclear cause and ventricular arrhythmia in the context of underlying heart disease. In this retrospective study, consecutive patients with an ICD implanted for secondary prevention in the University Medical Center Groningen (UMCG), the Netherlands between 1 January 2012 and 31 December 2018 were included. Patients were classified as having ventricular arrhythmia of unclear cause if no clear cause was found which could explain the index ventricular arrhythmia. The primary outcome was appropriate ICD therapy. The study population consisted of 257 patients. In 220 patients, an underlying heart disease could be identified as the cause of ventricular arrhythmia, while 37 patients had an unclear cause of ventricular arrhythmia. The median age was 64 years (interquartile range (IQR) 53-72 years). Forty-five (18%) patients were women. During a median duration of follow-up of 6.2 years (IQR 4.8-7.8 years), appropriate ICD therapy occurred in 95 (37%) patients. This number was 90 (41%) in the group with a clear etiology and 5 (14%) in the group with an unclear etiology. In multivariable analysis, index ventricular arrhythmia of unclear cause was associated with fewer appropriate ICD therapies (HR 0.37 [95% CI 0.14-0.99]; p = 0.048), as well as an increased risk of inappropriate ICD shocks (HR 3.71 [95% CI 1.17-11.80]; p = 0.026). Index ventricular arrhythmia of unclear cause was significantly associated with fewer appropriate ICD therapies.

Long-term Clinical Outcomes of Implantable Cardioverter Defibrillator Recipients in New Zealand

The long-term clinical outcomes of implantable cardioverter defibrillator (ICD) recipients across New Zealand are unknown. This study provides a detailed analysis of long-term clinical outcomes of ICD recipients in New Zealand over the past decade. All patients with an ICD implant between 2010 and 2019 were identified using the National Minimum Dataset, which collects all public hospital admissions in New Zealand using International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification (ICD10-AM) procedure coding. There were 4,261 patients with a mean follow-up of 4.85±2.76 years. There were 1,739 (40.8%) primary prevention and 2,522 (59.2%) secondary prevention ICD recipients. The median age was 62 years and 78.9% were male. There was no significant difference in all-cause mortality between primary prevention or secondary prevention ICD recipients (21.7% vs 21.9%, p=0.99). In the primary prevention ICD group, heart failure (HF) hospitalisation more frequently occurred (32.7% vs 26.1%, p<0.001) but hospitalisations with ventricular arrhythmia (VA) were less common (16.7% vs 27.1%, p<0.001). Compared with ICD recipients with non-ischaemic aetiology for HF, those with ischaemic HF had higher all-cause mortality (30.0% vs 16.1%, p<0.001), HF hospitalisation (38.0% vs 22.4%, p<0.001), and hospitalisation with VA (27.9% vs 19.4%, p<0.001). In New Zealand ICD recipients, there was no difference in all-cause mortality between primary prevention and secondary prevention ICD implants. However, ICD recipients with ischaemic aetiology for HF had significantly higher all-cause mortality, HF hospitalisation, and hospitalisation with VA.