Primary Implantable Cardioverter-defibrillator Research Articles

Risk stratification for a primary prevention ICD: Performance of the MADIT-ICD Benefit Score in contemporary real world patients

Abstract Background We have recently developed the MADIT-ICD Benefit Score to improve risk stratification for primary implantable cardioverter defibrillator (ICD) implantation by assessing the competing risk of life-threatening ventricular tachyarrhythmia (VTA) vs. non-arrhythmic mortality based using simple clinical variables. Patients with a MADIT-ICD Benefit Score of < 50 are more likely to experience non-arrhythmic mortality than life-threatening VTA, and therefore derive limited benefit from a prophylactic ICD. Purpose We aimed to provide data on the performance of the MADIT-ICD Benefit Score in a real world population, comprising patients with HFrEF and either ischemic or nonischemic cardiomyopathy (ICM/NICM) who are treated with contemporary guideline-directed medical therapy (GDMT). Methods The study population comprised 2875 patients who were implanted with a primary prevention ICD and prospectively followed in a large tertiary healthcare system (the University of Rochester Medical Center, including 3 affiliated hospitals in Upstate New York) between 2017 through 2023. Arrhythmic events were captured from device interrogation data, which were blindly adjudicated by 2 electrophysiologists. Results Among the 2875 study patients, mean age was 62 ± 15 years, 1265 (44%) were women, and 1667 (58%) had ICM. Guideline-directed medical therapies, including angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, angiotensin receptor/neprilysin inhibitors, beta-blockers, mineralocorticoid receptor antagonists, and sodium-glucose transport protein 2 (SGLT2) inhibitors, were prescribed to 43%, 36%, 96%, 67% and 32% of study patients, respectively. The 2-year cumulative incidence of VTA, after accounting for the competing risk of death, was 19% vs. 11% in patients with a Score of ≥50 vs. <50, respectively (p<0.001; Figure 1A). Findings regarding ICD shocks were consistent (8% vs. 4%, respectively, p<0.001; Figure 1B) The rate of VTA events at 4 years was directly correlated with increasing quartiles of the MADIT-ICD Benefit Score, while the corresponding rates of non-arrhythmic mortality were inversely correlated with score quartiles (Figure 1C). A similar direct correlation with increasing Benefit Score quartiles was observed when the endpoint of ICD shocks was assessed (Figure 1D). Accordingly, the benefit of the ICD (calculated as the difference between predicted rates of VTA/shock events and corresponding rates of non-arrhythmic mortality) was attenuated with decreasing quartiles of the MADIT-ICD Benefit Score (Figures 1C and 1D; right column). Conclusions We show good performance of the MADIT-ICD Benefit Score in a large cohort of real world ICD recipients who are treated with contemporary GDMT. These data support the use of the MADIT-ICD Benefit Score for improved risk stratification and for shared decision-making in contemporary candidates for a primary prevention ICD.

Ventriculo-arterial (VA) coupling and fQRS as new selection criteria for primary prevention ICD placement

For decades, left ventricular ejection fraction (LVEF < 35%) has been a mainstay for identifying heart failure (HF) patients most likely to benefit from an implantable cardioverter defibrillator (ICD). However, LVEF is a poor predictor of sudden cardiac death (SCD) and ignores 50% of HF patients with mildly reduced and preserved LVEF. The current international guidelines for primary prophylaxis ICD therapy are inadequate. Instead of LVEF, which is not a good measure of LV contractility or hemodynamic characterization, we hypothesize ventriculo-arterial (VA) coupling combined with fragmented QRS (fQRS) will improve risk stratification and patient suitability for an ICD. Quantifying cardiac and aortic mechanics, and predicting active arrhythmogenic substrate, from varying fQRS morphologies, may help to stratify ischemic and non-ischemic patients with different functional capacities and predisposition for lethal arrhythmias. We propose HF patients with a low physiological reserve may not benefit from ICD therapy, whereas those patients with higher reserves and extensive arrhythmogenic substrate may benefit. Our hypothesis combining VA coupling with fQRS changes has the potential to widen HF patient participation (low and high LVEF) and advance personalized medicine for HF patients at high risk of SCD.

Impact of preventive substrate catheter ablation on implantable cardioverter-defibrillator interventions in patients with ischaemic cardiomyopathy and infarct-related coronary chronic total occlusion.

Primary prevention patients with ischaemic cardiomyopathy and chronic total occlusion of an infarct-related coronary artery (CTO) are at a particularly high risk of implantable cardioverter-defibrillator (ICD) therapy occurrence. The trial was designed to evaluate the efficacy of preventive CTO-related substrate ablation strategy in ischaemic cardiomyopathy patients undergoing primary prevention ICD implantation. The PREVENTIVE VT study was a prospective, multicentre, randomized trial including ischaemic patients with ejection fraction ≤40%, no documented ventricular arrhythmias (VAs), and evidence of scar related to the coronary CTO. Patients were randomly assigned 1:1 to a preventive substrate ablation before ICD implantation or standard therapy with ICD implantation only. The primary outcome was a composite of appropriate ICD therapy or unplanned hospitalization for VAs. Secondary outcomes included the primary outcome's components, the incidence of appropriate ICD therapies, cardiac hospitalization, electrical storm, and cardiovascular (CV) mortality. Sixty patients were included in the study. During the mean follow-up of 44.7 ± 20.7 months, the primary outcome occurred in 5 (16.7%) patients undergoing preventive substrate ablation and in 13 (43.3%) patients receiving only ICD [hazard ratio (HR): 0.33; 95% confidence interval (CI): 0.12-0.94; P = 0.037]. Patients in the preventive ablation group also had fewer appropriate ICD therapies (P = 0.039) and the electrical storms (Log-rank: P = 0.01). While preventive ablation also reduced cardiac hospitalizations (P = 0.006), it had no significant impact on CV mortality (P = 0.151). Preventive ablation of the coronary CTO-related substrate in patients undergoing primary ICD implantation is associated with the reduced risk of appropriate ICD therapy or unplanned hospitalization due to VAs.

MRI Assessment of Myocardial Deformation for Risk Stratification of Major Arrhythmic Events in Patients With Non-Ischemic Cardiomyopathy Eligible for Primary Prevention Implantable Cardioverter Defibrillators.

Implantable cardioverter-defibrillator (ICD) intervention is an established prophylactic measure. Identifying high-benefit patients poses challenges. To assess the prognostic value of cardiac magnetic resonance imaging (MRI) parameters including myocardial deformation for risk stratification of ICD intervention in non-ischemic cardiomyopathy (NICM) while accounting for competing mortality risk. Retrospective and prospective. One hundred and fifty-nine NICM patients eligible for primary ICD (117 male, 54 ± 13 years) and 49 control subjects (38 male, 53 ± 5 years). Balanced steady state free precession (bSSFP) and three-dimensional phase-sensitive inversion-recovery late gadolinium enhancement (LGE) sequences at 1.5 T or 3 T. Patients underwent MRI before ICD implantation and were followed up. Functional parameters, left ventricular global radial, circumferential and longitudinal strain, right ventricular free wall longitudinal strain (RV FWLS) and left atrial strain were measured (Circle, cvi42). LGE presence was assessed visually. The primary endpoint was appropriate ICD intervention. Models were developed to determine outcome, with and without accounting for competing risk (non-sudden cardiac death), and compared to a baseline model including LGE and clinical features. Wilcoxon non-parametric test, Cox's proportional hazards regression, Fine-Gray competing risk model, and cumulative incidence functions. Harrell's c statistic was used for model selection. A P value <0.05 was considered statistically significant. Follow-up duration was 1176 ± 960 days (median: 896). Twenty-six patients (16%) met the primary endpoint. RV FWLS demonstrated a significant difference between patients with and without events (-12.5% ± 5 vs. -16.4% ± 5.5). Univariable analyses showed LGE and RV FWLS were significantly associated with outcome (LGE: hazard ratio [HR] = 3.69, 95% CI = 1.28-10.62; RV FWLS: HR = 2.04, 95% CI = 1.30-3.22). RV FWLS significantly improved the prognostic value of baseline model and remained significant in multivariable analysis, accounting for competing risk (HR = 1.73, 95% CI = 1.12-2.66). In NICM, RV FWLS may provide additional predictive value for predicting appropriate ICD intervention. 2 TECHNICAL EFFICACY: Stage 5.

Two-year outcomes of primary prophylactic use of defibrillators with ischemic and non-ischemic cardiomyopathy: propensity score-matched analysis from NIPPON STORM Study

Abstract Background In 2016, the DANISH study showed negative results regarding the efficacy of implantable cardioverter defibrillators (ICDs) for patients with non-ischemic cardiomyopathy (NICM) and reduced left ventricular ejection fraction (LVEF). Thus, the ESC guidelines downgraded the indication for primary ICD prophylaxis for NICM patients with reduced LVEF from Class I to IIa. However, the change might be felt somewhat improper in the real wolrd ICD therapy and decided to use the Nippon storm study, a prospective registry study in Japan, to determine whether the DANISH results are of equal value in the clinical setting. Objective To determine the efficacy of ICDs as primary prevention in patients with NICM, the incidence of ICD appropriate therapy in patients with NICM was compared with that in patients with ischemic cardiomyopathy (ICM) for which primary ICD efficacy is generally recognized as a Class I indication. Methods We selected 1274 patients with underlying cardiac disease from a total of 1548 patients enrolled in the Nippon storm study. We analyzed data of 451 patients with LVEF ≤35% owing to NICM or ICM who underwent ICD implantation of primary prophylaxis (men, 78%; age, 65±12 years; LVEF, 25±1.4%; cardiac resynchronization therapy, 20%; ICM, 33%). All patients were followed up for at least 2 years. Patient selection was performed by employing the propensity score matching method with a digit-matching algorithm for clinical factors, ie, age, sex, cardiac resynchronization therapy with a defibrillator, LVEF. After all propensity score matches had been performed, we compared baseline covariates between the 2 groups: 132 patients with NICM and 132 with ICM. The cumulative incidences of ICD therapies (including both anti-tachycardia pacing and shock therapies) were calculated using competing risk analysis, because death is a competing risk for loss to follow-up. Results In the matched cohort, the 2-year appropriate ICD therapy risks were 27.7% and 12.2% in NICM and ICM groups, respectively (HR = 0.390 [95% CI, 0.218–0.701; P = 0.002) (Figure A). Two-year appropriate ATP therapy risks were 25.5% and 11.4% in NICM and ICM groups, respectively (HR = 0.417 [95% CI, 0.226– 0.776; P = .005]) (Figure B), and appropriate shock therapy risks were 6.3% and 1.6% in NICM and ICM groups, respectively (HR = 0.230 [95% CI, 0.049–1.085; P = .063]) (Figure C). Conclusion The present subanalysis of the Nippon Storm Study revealed that the risk for appropriate ICD therapy was significantly higher in the patients with NICM than in those with ICM based on our propensity score–matching method.

Long-Term Clinical Outcomes of Implantable Cardioverter Defibrillator Recipients in New Zealand: A Subanalysis by Sex, Age Group, and Ethnicity

The long-term clinical outcomes of implantable cardioverter defibrillator (ICD) recipients across New Zealand are unknown. This study provides a detailed subanalysis of long-term clinical outcomes of ICD recipients by sex, age group, and ethnicity. 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. The median age was 62 years and 78.9% were male. The all-cause mortality was higher in males compared with females (23.1% vs 17.2%; p<0.001). There was no significant difference by primary and secondary prevention indication ICD in each sex group. Heart failure (HF) hospitalisation was higher in males compared with females (29.4% vs 26.6%; p=0.009). All-cause mortality was highest in the age group of ≥80 years and lowest in those <40 years (44.1% vs 8.4%, p<0.001). HF hospitalisation was highest in the age group of 70–79 years and lowest in the age group <40 years (36.5% vs 16.1%; p<0.001). All-cause mortality was highest in Māori and lowest in Asians (26.7% vs 15.9%; p<0.001). Heart failure hospitalisation was highest in Māori and lowest in Europeans (36.1% vs 26.3%; p<0.001). In New Zealand, all-cause mortality and HF hospitalisation was highest in males and Māori ICD recipients. These disparities in clinical outcomes warrant further investigation.

From premature ventricular complexes to sustained ventricular tachycardia : An overview of innovations in the 2022 ESC Guideline on the therapy of ventricular arrhythmias

The recent 2022 European Society of Cardiology Guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death are an update of the former 2015 European guidelines. With multiple tables, algorithms, and comprehensive integration of underlying study data, the new guideline is auser-oriented reference book for clinical practice that also covers special clinical situations such as cardiac arrhythmias in pregnancy or in the context of sports. Regarding the acute treatment of ventricular arrhythmias, cardioversion is now recommended in case of hemodynamically tolerated arrhythmias. Beyond that, the guideline places special emphasis on the management of the electrical storm. In long-term therapy, recommendations for drug therapy have been aligned with current heart failure guidelines. Catheter ablation of ventricular arrhythmias has gained importance not only for recurrent ventricular tachycardia under chronic amiodarone therapy and as an alternative to implantable cardioverter-defibrillators (ICDs) in selected patients with coronary artery disease, but especially for the treatment of idiopathic premature ventricular contractions and tachycardias. Risk stratification and criteria for primary preventive ICDs are still controversial topics, which are discussed in detail based on the specific disease entities.

Prediction of Left Ventricular Ejection Fraction Change Following Treatment With Sacubitril/Valsartan

BackgroundSacubitril/valsartan (Sac/Val) improves left ventricular ejection fraction (LVEF) in heart failure (HF) with reduced ejection fraction regardless of previous treatments. Improvements in LVEF may change eligibility for primary implantable cardioverter-defibrillator (ICD) placement. Awaiting LVEF improvement may expose patients to potential risks for arrhythmic complications. ObjectivesThe authors sought to develop a model predicting LVEF change after Sac/Val therapy. MethodsA total of 416 persons with HF and LVEF of <35% were included in this analysis. Following initiation of Sac/Val, echocardiographic parameters were measured serially for 1 year. A machine learning algorithm was implemented to develop a risk model for predicting the persistence of LVEF of <35% after 1 year and was validated in a separate group of study participants. ResultsBaseline LVEF, left ventricular mass index, HF duration, age, N-terminal pro–B-type natriuretic peptide concentration at baseline and change by day 14, and body mass index were the most significant factors for identifying lack of LVEF improvement to ≥35% after 1 year. In the training and validation cohorts, the areas under the model curve for predicting lack of LVEF improvement were 0.92 and 0.86, respectively. Three categories of likelihood for LVEF of <35% after 1 year of Sac/Val treatment were developed based on the model predictions: 3.8%, 30.1%, and 83.7%. During follow-up, arrhythmia event rates were 0.9%, 2.9%, and 6.7% in these groups, respectively. ConclusionsMany persons with HF with reduced ejection fraction eligible for ICD insertion experience an increase in LVEF to ≥35% after treatment with Sac/Val. Early identification of those less likely to improve their LVEF might allow for more refined selection of primary ICD candidates. (Effects of Sacubitril/Valsartan Therapy on biomarkers, Myocardial Remodeling, and Outcomes [PROVE-HF]; NCT02887183)

Pacemaker implantation due to cardiac conduction disease in patients with subsequent cardiac sarcoidosis may be a marker of early disease and is associated with adverse 5-year clinical outcome

Abstract Background Sarcoidosis is a rare chronic granulomatous disease of unknown aetiology with potential multi-organ involvement and end-organ dysfunction. Cardiac sarcoidosis (CS) occurs in 5–10% of patients with sarcoidosis though an up to 25% prevalence has been reported by imaging and autopsy studies, suggesting undiagnosed silent disease. Progression of CS, especially if undiagnosed and untreated, may lead to heart failure, atrioventricular block (AVB), ventricular arrhythmias and sudden cardiac death. Aim We sought to determine whether signs of cardiac conduction disease (CCD) prior to the clinical diagnosis of sarcoidosis is associated with poor long-term prognosis in patients with imaging-confirmed cardiac involvement. Method All patients diagnosed with CS since January 1, 2000, at a tertiary centre (n=112) with either primary cardiac localisation (n=70) or cardiac involvement in otherwise primary non-cardiac sarcoidosis (n=42) as per imaging were included. Swedish pacemaker and ICD registry was used to identify patients who received cardiac implantable electronic device (CIED). CCD-related indications for CIED implant were defined as AVB, bi- or trifascicular block. Kaplan-Meier curve analysis and time-dependent Cox regression analysis were used for estimation of risk of death from any cause (primary endpoint), death or upgrade to cardiac resynchronization therapy (CRT, secondary endpoint) at 5 years after CS diagnosis, stratified for history of CIED implantation due to CCD. Hazard ratios were calculated in a univariate model and adjusted for age, gender and the use of implantable cardioverter-defibrillator (ICD). Results Mean age at CS diagnosis was 59±13 years (54% male). Forty-nine patients received CIED implant at a mean age of 54±13 years (14 pacemakers (29%), 14 primary prevention ICDs (29%), 13 secondary prevention ICDs (27%) and 8 CRT-D (16%)). The median time in years from CS diagnosis to CIED implant was for pacemaker −2.5 [IQR 8.5], primary ICD −0.3 [IQR 3.8], secondary ICD −4.0 [IQR 10.4] and CRT-D −0.03 [IQR 1.5]. CIED was implanted prior to CS diagnosis in 29 patients of whom 17 had CCD [MOU1] as the indication for implant. At 5-year follow-up in the CS cohort, 16 patients died and 2 underwent device upgrade to CRT (median 3.2 years [IQR 1.2]). CIED implant prior to CS diagnosis was associated with the primary (HRuni 3.5, 95% CI 1.2–10, p=0.021, Figure 1; HRadj 10.5, 95% CI 1.7–63, p=0.01) and the secondary (HR 3.5, 95% CI 1.2–10, p=0.019; HRadj 8.2, 95% CI 1.6–41.1, p=0.011) endpoints. Conclusion CIED implantation due to CCD can be an early manifestation of undiagnosed CS. It was observed in 15% of all patients with CS and was associated with adverse outcome. Identification of signs of CCD necessitating CIED implant in a middle-aged patient may motivate further diagnostic work-up aimed at timely detection of concealed CS. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Hjärt-Lung fondenAvtal om Läkarutbildning och Forskning

CRT-D non-responders have worse cardiovascular outcome than patients after primary ICD implantation with similar baseline left ventricular ejection fraction

Abstract Background Cardiac resynchronisation therapy (CRT) fails to improve echocardiographic parameters and outcome in 20–40% of heart failure (HF) patients with reduced ejection fraction (EF) referred to as CRT non-responders (CRT-NR). The aim of this study was to compare the outcomes of CRT-NR patients who received a CRT defibrillator (CRT-D) device with patients after primary implantable cardioverter-defibrillator (ICD) implantation for impaired left ventricular (LV) function. Methods CRT-NR status was defined as no or less than 10% improvement in LV EF 12 months post implantation. CRT-NR patients and those after primary ICD implantation for LV EF&amp;lt;35% were identified in our database between 2010 and 2019. CRT-NR patients were further categorized as progressors (decrease in LV EF ≥5%) or non-progressors (LV EF change between +9 to −5%). Primary endpoint was all-cause mortality or the need for heart transplantation during follow-up. Statistical significance was assessed by Log-rank test of Kaplan-Meier survival analysis. Results 151 CRT-NR patients and 219 patients after primary ICD implantation were identified with a mean ± SEM follow-up of 43.7±2.5 and 47.3±2.2 months, respectively. Baseline (preoperative) LV EFs were higher (p&amp;lt;0.05) for the overall CRT-NR group (EF = 27.4±0.4%) than for the ICD group (EF = 25.2±0.3%) Further, both CRT-NR subgroups of progressors (n=49; EF = 28.6±0.7%) and non-progressors (n=102; EF = 26.9±0.5%) had also significantly higher baseline LV EF as compared to ICD patients (p&amp;lt;0.05). No statistical significance was found between the two CRT-NR subgroups. Event free median survival for the overall CRT-NR group (55.6 months) was significantly worse than for the ICD group (79.6; p&amp;lt;0.05). This difference was driven by progressor patients who had a significantly worse event free survival (37.8 months, p&amp;lt;0.05) than ICD patients, while vent free survival in non-progressors (60.8 months) was comparable to ICD patients (p=0.18). Conclusion Progressor subgroup of CRT-NR have worse outcome as compared to non-progressors and also to those after primary prevention ICD implantation. The poor prognosis of these patients should have implications for timely decision regarding all therapeutic measures currently available for the management of heart failure. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Project no. TKP2021-EGA-18 has been implemented with the support provided from the National Research, Developement and Innovation Fund of Hungary, financed under the TKP2021-EGA funding scheme

Arrhythmia in hypertrophic cardiomyopathy: Risk prediction using contrast enhanced MRI, T1 mapping, and personalized virtual heart technology

BackgroundHypertrophic cardiomyopathy (HCM), a disease with myocardial fibrosis manifestation, is a common cause of sudden cardiac death (SCD) due to ventricular arrhythmias (VA). Current clinical risk stratification criteria are inadequate in identifying patients who are at risk for VA and in need of an implantable cardioverter defibrillator (ICD) for primary prevention. ObjectiveWe aimed to develop a risk prediction approach based on imaging biomarkers from the combination of late gadolinium contrast-enhanced (LGE) MRI and T1 mapping. We then aimed to compare the prediction to a virtual heart computational risk assessment approach based on LGE-T1 virtual heart models. MethodsThe methodology involved combining short-axis LGE-MRI with post-contrast T1 maps to define personalized thresholds for diffuse and dense fibrosis. The combined LGE-T1 maps were used to evaluate imaging biomarkers for VA risk prediction. The risk prediction capability of the biomarkers was compared with that of the LGE-T1 virtual heart arrhythmia inducibility simulation. VA risk prediction performance from both approaches was compared to clinical outcome (presence of clinical VA). ResultsImage-based biomarkers, including hypertrophy, signal intensity heterogeneity, and fibrotic border complexity, could not discriminate high vs low VA risk. LGE-T1 virtual heart technology outperformed all the image-based biomarker metrics and was statistically significant in predicting VA risk in HCM. ConclusionsWe combined two MR imaging techniques to analyze imaging biomarkers in HCM. Raw and processed image-based biomarkers cannot discriminate patients with VA from those without VA. Hybrid LGE-T1 virtual heart models could correctly predict VA risk for this cohort and may improve SCD risk stratification to better identify HCM patients for primary preventative ICD implantation.

QRS fragmentation is associated with increased risk of ventricular arrhythmias in high-risk patients; Data from the SMASH 1 Study.

IntroductionQRS fragmentation (fQRS), defined as the presence of additional spikes within the QRS complex, has been associated with myocardial conduction abnormalities and arrhythmogenicity.ObjectiveWe aimed to assess whether fQRS is associated with incident ventricular arrhythmias (VA) in high‐risk patients treated with implantable cardioverter‐defibrillator (ICD) for primary and secondary prevention.MethodsIn a prospective observational multicenter study, we included 495 patients treated with ICD. fQRS was analyzed according to previously validated criteria, by two physicians blinded for outcome data. Incident VA were obtained from ICD recordings.ResultsECG recordings interpretable for fQRS were available in 459 patients (93%), aged 66 ± 12 years with left ventricular ejection fraction 40% ± 13%. fQRS was present in 52 patients (11%) with comparable baseline characteristics to patients without fQRS, except higher age, higher prevalence of coronary artery disease (CAD), lower prevalence of cardiomyopathy, and more frequently a secondary prevention ICD indication. Among patients with native QRS, those with fQRS had similar QRS duration and axis to those without fQRS. During 3.1 ± 0.7 years follow‐up, 126 patients (28%) had ≥1 VA . fQRS was associated with increased risk of VA (HR 3.41 [95% CI 2.27–5.13], p < .001), which persisted after adjusting for age, gender, sex, BMI, CAD, heart failure, renal function, ICD indication, QRS duration, QRS axis, Q waves, and bundle branch block. fQRS was more strongly associated with VA in patients with a primary (HR 6.05 [95% CI 3.16–11.60]) versus secondary (HR 2.39 [95% CI 1.41–4.04]) ICD indication (p‐for‐interaction = .047).ConclusionsfQRS is associated with threefold increased risk of VA in high‐risk patients, independent of established risk factors.

Arrhythmic and Mortality Outcomes Among Ischemic Versus Nonischemic Cardiomyopathy Patients Receiving Primary ICD Therapy.

This study sought to determine the association of cardiomyopathy etiology with the likelihood of ventricular arrhythmias, appropriate implantable cardioverter-defibrillator (ICD) therapy, and mortality. There are conflicting data on the benefit of primary prevention ICD therapy in patients with ischemic versus nonischemic cardiomyopathy (ICM/NICM). The study population comprised 4803 patients with ICM (n=3,106) or NICM (n=1,697) with a primary prevention ICD enrolled in 5 randomized trials conducted between 1997 and 2017. The primary end point was sustained ventricular tachycardia (VT)≥200 beats/min or ventricular fibrillation (VF). Secondary end points included appropriate ICD therapy and all-cause mortality. Differences in cause-specific mortality, including noncardiac, sudden cardiac, and non-sudden cardiac death, were also examined. Patients with ICM were significantly older and had more comorbid conditions, whereas those with NICM had a more advanced heart failure class at enrollment and were more often prescribed medical or cardiac resynchronization therapy for heart failure. Multivariate analysis showed that ICM versus NICM had a similar risk of VT/VF events (HR: 0.98 [95%CI: 0.79-1.20]) and appropriate ICD therapy (HR: 1.03 [95%CI: 0.87-1.22]), whereas the risk of all-cause mortality was 1.8-fold higher among ICM versus NICM patients (HR: 1.84 [95%CI: 1.42-2.38]), dominated by non-sudden cardiac mortality. Combined data from 5 landmark ICD clinical trials show that ICM patients experience a similar risk of life-threatening ventricular arrhythmic events but have an increased risk of all-cause mortality, dominated by non-sudden cardiac death, compared with NICM patients.

Depressive symptoms in patients after primary and secondary prophylactic ICD implantation.

Implantable cardioverter defibrillators (ICD) are successfully used to treat life-threatening arrhythmias and prevent sudden cardiac death. However, they are also known to have a major psychological impact leading to higher prevalence of depression and anxiety in a substantial proportion of patients. The aim of this study was to assess the prevalence of depressive symptoms in a large cohort of ICD carriers with a different clinical background and to compare prevalence and risk factors between patients with primary and secondary prophylactic indication for ICD implantation. 315 out of 622 patients (50.6%), who regularly attended ICD assessments at the University Hospital Zurich completed the Beck Depression Inventory (BDI I-II) to estimate current depressive symptoms. Overall, depressive symptoms were common in ICD patients, with 20.3% of the patients showing clinically relevant depression (12.4% mild depressive symptoms, 6.0% moderate, 1.9% severe). Moderate to severe depressive symptoms seem to be more likely in patients with secondary prophylactic indication of the ICD as compared to a group of patients with primary prophylactic implantation. Patients that received more than 5 ICD shocks since implantation reveal more depressive symptoms than those with less events. Mean BDI Score in total (n = 315) was at 8.44 ± 7.56 without a statistically significant difference between the primary (M = 8.04 ± 7.10, n = 153) and secondary (M = 8.81 ± 7.98, n = 162) preventive group (p value = 0.362), even after adjustment for various clinical characteristics. ICD patients should therefore be well supported and advised concerning the psychological impact of their device and particular aspects of daily life concerns (e.g. physical activity), with a special focus on patients, who have received multiple shocks.

Survival among ischemic and non-ischemic heart failure patients with primary implantable cardioverter defibrillator therapy in Korea: a nationwide cohort study

Abstract Background Concerns still exist about the efficacy of prophylactic implantable electrocardiogram defibrillators (ICD) in patients with non-ischemic heart failure (HF). We evaluated the mortality and predictors of mortality in patients with prophylactic ICD implantation for ischemic and non-ischemic HF. Methods From 2008 to 2017, 1097 patients (667 non-ischemic; 430 ischemic) with prophylactic ICD implantation who were aged 19 years or older were identified from the Korean National Health Insurance Service database. We used propensity score overlap weighting to correct for differences between two groups. Results Compared with non-ischemic HF patients, ischemic HF patients were older (67.0±10.1 years vs. 61.8±14.2), more often male (71.4% vs. 63.7%), and had more comorbidities. During a median follow-up of 37.3 months (interquartile range (IQR), 14.2–53.8 months), all-cause death was higher in unweighted ischemic than non-ischemic HF patients (10.9 and 6.4 per 100 person-years, hazard ratio [HR] 1.74, 95% confidence interval [CI] 1.38–2.20, p&amp;lt;0.001). However, after weighting, annual all-cause mortality rate was similar in both groups (9.5 vs. 8.8 per 100 person-years) without difference in the risk of all-cause death (HR 1.08, 95% CI 0.68–1.71, p=0.755). Older age and chronic kidney disease were independent predictors of all-cause mortality in both groups. There was also no difference in cardiac and non-cardiac mortality between weighted non-ischemic and ischemic HF groups. Conclusions All-cause, cardiac and non-cardiac mortality were similar between non-ischemic and ischemic HF patients undergoing prophylactic ICD implantation. Our findings support the current guidelines recommendation for primary-prevention ICD in HFrEF patients with ischemic and non-ischemic HF. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Korean Healthcare Technology R&amp;D project funded by the Ministry of Health and Welfare

Novel Implantable Cardioverter Defibrillator Programming With High Rate Cut-Off, Long Detection Intervals and Multiple Anti-Tachycardia Pacing Reduces Mortality.

Implantable cardioverter defibrillator (ICD) therapies, even when appropriate, are associated with increased risk. Therapy-reducing strategies have been shown to reduce the mortality rate.Methods and Results:In total, 895 patients with ICD and cardiac resynchronization therapy with defibrillation function (CRT-D) were included in the study; of these, 506 (57%) patients undergoing secondary prevention were included. Devices implanted before May 2014 were programmed according to conventional programming (CP), the others according to our novel programming (NP) with high rate cut-off, longer detection intervals and 4-6 anti-tachycardia pacing (ATP) trains in the ventricular tachycardia (VT) zone. Time-to-first-event for mortality, appropriate and inappropriate therapies were analyzed. Follow-up time was 24.0 months (IQR 13.0-24.0 months). There was a significant reduction in mortality rate (11.4% vs. 25.4%, P<0.001) and in the rate of appropriate (18.8% vs. 42.2%, P<0.001) and inappropriate therapies (5.2% vs. 18.0%, P<0.001) with NP according to Kaplan-Meier analyses. In multivariate analysis, NP (hazard ratio [HR]=0.35; P<0.001), chronic kidney disease (HR=1.55), reduced ejection fraction (EF) (HR=1.35), secondary ICD indication (HR=2.35) and age at implantation (HR=1.02) were associated with mortality reduction. NP was also associated with significant reduction in the rate of appropriate and inappropriate therapies. These results were consistent after stratification for primary and secondary prevention. Novel ICD programming reduced mortality and morbidity due to appropriate or inappropriate ICD therapies in secondary as well as in primary ICD indication.

The impact of transvenous cardioverter-defibrillator implantation on quality of life, depression and optimism in dialysis patients: report on the secondary outcome of QOL in the randomized controlled ICD2 trial

RationaleThe impact of prophylactic implantable cardioverter-defibrillator (ICD) implantation on the psychological well-being of patients on dialysis is unknown.ObjectiveWe aimed to identify the effect of primary ICD implantation on quality of life (QoL), mood and dispositional optimism in patients undergoing dialysis.Methods and resultsWe performed a prespecified subanalysis of the randomized controlled ICD2 trial. In total, 177 patients on chronic dialysis, with an age of 55–81 years, and a left ventricular ejection fraction of ≥ 35%, were included in the per-protocol analysis. Eighty patients received an ICD for primary prevention, and 91 patients received standard care. The Short Form-36 (SF-36), Geriatric Depression Scale-15 (GDS-15), Revised Life Orientation Test (LOT-R) questionnaires were administered prior to ICD implantation (T0), and at 1-year follow-up (T1) to assess QoL, depression and optimism, respectively. The patients were predominantly male (76.0%), with a median age of 67 years. Hemodialysis was the predominant mode of dialysis (70.2%). The GDS-15 score difference (T1 − T0) was 0.5 (2.1) in the ICD group compared with 0.3 (2.2) in the control group (mean difference − 0.3; 95% CI − 1.1 to 0.6; P = 0.58). The LOT-R score difference was − 0.2 (4.1) in the ICD group compared with − 1.5 (4.0) in the control group (mean difference − 1.1 (0.8); 95% CI − 2.6 to 0.4; P = 0.17). The mean difference scores of all subscales of the SF-36 were not significantly different between randomization groups.ConclusionsIn our population of patients on dialysis, ICD implantation did not affect QoL, mood or dispositional optimism significantly during 1-year follow-up.Clinical Trial RegistrationUnique identifier: ISRCTN20479861. http://www.controlled-trials.com.

Extent of peri-infarct scar on late gadolinium enhancement cardiac magnetic resonance imaging and outcome in patients with ischemic cardiomyopathy

Only a minority of patients who receive an implantable cardioverter-defibrillator (ICD) on the basis of left ventricular ejection fraction receive appropriate ICD therapy. Peri-infarct scar zone assessed by late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) is a possible substrate for ventricular tachyarrhytmias (VTAs). The aim of our prospective study was to determine whether LGE-CMR parameters can predict the occurrence of VTA in patients with ischemic cardiomyopathy (ICM). Two hundred sixteen patients with ICM underwent CMR imaging before primary or secondary ICD implantation and were prospectively followed. We assessed CMR indices and CMR scar characteristics (infarct core and peri-infarct zone) to predict outcome and VTAs. Patients were followed up for 1497 days (interquartile range 697-2237 days). Forty-seven patients (21%) received appropriate therapy during follow-up. Patients with appropriate ICD therapy had smaller core scar (31.5% ± 8.5% vs 36.8% ± 8.9%; P = .0004) but larger peri-infarct scar (12.4% ± 2.6% vs 10.5% ± 2.9%; P=.0001) than did patients without appropriate therapy. In multivariate Cox regression analysis, peri-infarct scar (hazard ratio 1.15; 95% confidence interval 1.07-1.24; P = .0001) was independently and significantly associated with VTAs whereas left ventricular ejection fraction, right ventricular ejection fraction, core scar, and left atrial ejection fraction were not. Scar extent of peri-infarct border zone was significantly associated with appropriate ICD therapy. Thus, LGE-CMR parameters can identify a subgroup of patients with ICM and an increased risk of life-threatening VTAs.

Cognitive Function of Recipients of Primary or Secondary Defibrillator Therapy: A Comparative Study Involving Nondefibrillator Patients With Systolic Heart Failure.

The extent to which cognitive function differs between patients who receive implantable cardioverter-defibrillator (ICD) therapy and patients with heart failure (HF) who do not receive ICD therapy remains to be elucidated. The aim of this study was to compare the cognitive function between patients with primary or secondary ICDs and patients with HF without an ICD. This descriptive, comparative study included 116 patients who received ICDs and 74 patients with HF who did not receive ICDs. Patients underwent neuropsychological assessment for general cognition, memory, and executive function. Immediate recall memory loss (18.9%) occurred more often in patients with HF without an ICD than in patients with primary (3.1%) and secondary (7.1%) ICDs (P = .018). After adjusting for age and education, delayed recall memory of patients with HF without ICDs was significantly worse than that of patients with primary ICDs (4.0 vs 6.5; P < .001), whereas delayed recall memory of patients with primary ICDs was better than that of patients with secondary ICDs (6.0 vs 6.5; P = .006). Executive function of patients with HF without ICDs was significantly worse than that of patients with primary (35 vs 58 seconds; P < .001) and secondary (28 vs 58 seconds; P = .0012) ICDs. Patients with ICDs, regardless of primary or secondary indication, had less impairment of memory and executive function than patients with HF without ICDs, implying that ICD therapy did not interfere with cognitive performance. Cognitive screening as a part of routine care could be helpful for identifying impairment and implementing early cognitive training, especially in patients with HF.

Effect of physical and psychocognitive function and perceived health status on 12-month adverse cardiac events among implantable cardioverter-defibrillator recipients

BackgroundPost-implant recovery in patients with implantable cardioverter-defibrillators (ICDs) is often compromised because of reduced physical and psycho-cognitive function and poor health perception, leading to short event-free survival. ObjectivesTo examine the effects of psychocognitive function, health perception, and ICD-related factors on 12-month cardiac events among ICD patients. MethodsUsing a prospective study design, ICD patients underwent baseline assessment and were followed for 12 months to assess cardiac events. ResultsCardiac events occurred in 14 patients (18.9%) (N = 74: age, 58 years; primary ICDs, 45.9%). Time after ICD implant (odds ratio [OR] = 1.002; p = .028) and executive function (OR = 1.021; p = .027) were significant predictors of 12-month cardiac events, while other physical and psychological indices were not. ConclusionsReduced executive function and longer time after implant predicted the events. Healthcare professionals need to assess executive function and provide treatment and support to improve executive function.