Efficacy and safety of the subcutaneous implantable cardioverter defibrillator in patients with and without obesity: An international, bicentric retrospective registry.

Defibrillation Testing During Implantation of Subcutaneous Implantable Cardioverter Defibrillators.

Efficacy and safety of the subcutaneous implantable cardioverter-defibrillator in patients with and without obesity: A meta-analysis

Screening tests conducted at rest may be inadequate for the prediction of the T-wave oversensing (TWOS) in subcutaneous implantable cardioverter defibrillator (S-ICD) candidates with Brugada syndrome (BrS) because of the dynamic nature of electrocardiogram (ECG) morphology. We evaluated the utility of ECG screening during drug challenge (DC) for prediction of TWOS in BrS patients implanted with an S-ICD. The study enrolled 6 consecutive BrS patients implanted with an S-ICD. In addition to baseline ECG screening, pre-implant screening during DC using a sodium channel blocker was performed in all patients. All patients underwent appropriate morphological analysis on baseline ECG screening; however, 2 BrS patients (33%) showed inappropriate sensing during DC. During 243days of follow-up after S-ICD implantation, no patient experienced an appropriate shock. TWOS was confirmed during exercise testing in one of 2 patients who showed inappropriate sensing during DC. However, one patient with appropriate sensing during DC experienced recurrent episodes of inappropriate shocks due to TWOS during exercise. The present initial experience indicates that further studies are needed to detect the risk for TWOS from an S-ICD in BrS patients.

T-wave oversensing during drug challenge test after subcutaneous implantable cardioverter-defibrillator implantation in a patient with Brugada syndrome

Implantable Defibrillators for Primary Prevention of Sudden Death in Patients on Dialysis

The current status of primary prevention of sudden cardiac death (SCD) with implantable cardioverter defibrillator (ICD) in patients with heart failure with reduced ejection fraction remains to be fully elucidated in Japan. In the chronic heart failure (CHF) cohort study, the CHART-2 Study, we enrolled 2,778 consecutive patients with NYHA class II-III. According to the Japanese Circulation Society guideline of prophylactic ICD, we divided them into 3 groups: group A, class I indication; B, class IIa; and C, no indication. During the (median) 3.2-year follow-up, 79 fatal arrhythmic events (FAE), defined as composite of sudden cardiac/arrhythmic death, ventricular tachycardia/fibrillation and appropriate ICD therapy, occurred. In the groups A, B and C, the prevalence of FAE was 16.1%, 8.9% and 1.9%, respectively; the use of prophylactic ICD among those with FAE, however, was only 44%, 9% and 6%, respectively. In the groups A and B combined, chronic atrial fibrillation (cAF) and left ventricular end-diastolic dimension (LVDd) ≥ 65 mm were independent predictors of FAE, and, when combined, their prognostic impact was highly significant (hazard ratio, 7.01; P<0.001). Primary prevention of SCD with ICD in CHF patients is validated but is still underused in Japan, and the combination of cAF and LVDd ≥ 65 mm may be a useful indication of prophylactic ICD implantation.

The eligibility of patients with Brugada syndrome (BrS) for implantation of a subcutaneous implantable cardioverter defibrillator (S-ICD) is not well known. This study aimed to clarify the eligibility of BrS patients for S-ICD using electrocardiography (ECG) at rest and during exercise testing. We also analyzed factors associated with ineligibility for S-ICD from standard 12-lead ECG at rest. We enrolled 110 consecutive BrS patients who visited Okayama university hospital from December 2015 to December 2016. All patients were assessed for S-ICD eligibility, which required one lead to satisfy the S-ICD screening template. We assessed standard 12-lead ECG parameters in all participants. Of those who passed S-ICD screening, 45 patients were assessed for S-ICD eligibility during treadmill stress test. Mean age of study patients was 54 ± 13 years and 108 (98%) were men. In total, 89 patients (81%) satisfied S-ICD indications at rest. Existence of complete right bundle branch block (CRBBB) on standard 12-lead ECG was a significant predictor of ineligibility for S-ICD (odds ratio, 5.00; P=0.03; 95%CI, 1.14-21.98). Of the 45 patients who underwent treadmill stress testing, 11 patients (24%) showed ineligibility for S-ICD during the test. CRBBB was a predictor of ineligibility for S-ICD in patients with BrS. Sinus tachycardia changes ECG morphology in some patients and stress testing should be considered before S-ICD implantation.

ObjectivesThe objective of this meta-analysis of randomised controlled trials (RCTs) is to evaluate the role of primary prevention implantable cardioverter defibrillator (ICD) in patients with non-ischaemic cardiomyopathy (NICM).SettingA meta-analysis of...

Rationale, design, and baseline characteristics of the DANish randomized, controlled, multicenter study to assess the efficacy of Implantable cardioverter defibrillators in patients with non-ischemic Systolic Heart failure on mortality (DANISH)

BackgroundThe effect of implantable cardioverter defibrillators (ICD) in patients with continuous flow left ventricular assist devices (LVADs) on outcomes has not been evaluated in a randomized clinical trial.Methods and ResultsThis is a retrospective single‐center study that included patients who underwent continuous flow LVAD implantation at the Cleveland Clinic between October 2004 and March 2017. Patients were evaluated according to the presence or absence of ICD at the time of LVAD insertion. Among 486 patients in the study cohort, 387 (79.6%) had an ICD before LVAD insertion. Patients with ICD before LVAD were older and had lower use of pre‐LVAD inotropes, extracorporeal membrane oxygenation, and mechanical ventilation. There were 81 patients (21.4% of patients with ICD) who required 93 procedures after LVAD: 74 generator exchanges, 12 lead revisions, and 7 complete system removals because of infection. Of the 99 patients without ICD, 52 (53%) underwent ICD implantation: 29 for primary prevention and 23 for secondary prevention. Patients were followed for a median of 401 (interquartile range 150–966) days. The presence of a pre‐LVAD ICD was not associated with mortality in a multivariable model (hazard ratio 1.19, 95% CI 0.73–1.93, P=0.492), nor was the presence of an ICD at any point when analyzed as a time‐varying covariate (hazard ratio 1.05, 95% CI 0.50–2.20, P=0.907).ConclusionsThere is no apparent mortality benefit associated with an ICD in a contemporary cohort of patients with continuous flow LVADs to balance considerable morbidity involving ICD‐related procedures and complications.

Implantable Cardioverter Defibrillators in Patients with Continuous Flow Left Ventricular Assist Devices: Utilization Patterns, Shock Therapies and Complications.

Aims According to current guidelines, defibrillation testing (DT) for efficacy can be omitted in patients undergoing transvenous implantable cardioverter–defibrillator (T-ICD) implantation. DT is still recommended for patients at risk for a high defibrillation threshold (e.g. hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, right-sided implantations) and for ICD generator changes. Moreover, a class I recommendation remains to perform DT during the implantation of subcutaneous ICD (S-ICD). The aim of the present survey was to analyze the current practice of DT during T-ICD and S-ICD implantations in Italy. Methods In March 2021, an ad hoc questionnaire on the current performance of DT and the standard practice adopted during testing was completed by 72 operators at Italian centers implanting S-ICD and T-ICD. Results 48 (67%) operators reported never performing DT during de-novo T-ICD implantations, while no operators perform it systematically. The remaining respondents perform it in specific cases: right sided implantations (54%), poor signal sensing (46%), secondary prevention patients (42%), arrhythmic syndromes (13%), hypertrophic cardiomyopathy (8%). DT is never performed at T-ICD generator change. At the time of de-novo S-ICD implantation, DT is never performed by 9 (13%) operators and performed systematically by 48 (66%). The remaining operators perform DT in cases of: secondary prevention patients (73%), sub-optimal S-ICD placement (33%), non-compromised ejection fraction (33%) or obese patients (7%). DT is not performed at S-ICD generator change by 92% of operators. DT is conducted by delivering a first shock energy of 65J by 60% of operators, while the remaining 40% test lower energy values. The most frequently reported conditions for revising the system at the end of de- novo implantation procedure is high shock impedance (54%) and sub-optimal S-ICD placement or high PRAETORIAN score (50%). With adequately low shock impedance and optimal system placement, 37% of operators would accept a defibrillation margin &amp;lt;15J. Conclusion In current clinical practice, the vast majority of operators omit DT at T-ICD implantation, even when still recommended in the guidelines. DT is also frequently omitted at S-ICD implantation. We also report a wide variability among operators in the procedures followed during DT and in the criteria applied for defining the procedural success. Funding Acknowledgement Type of funding sources: None.

Background While strong evidence supports omitting defibrillation testing (DT) in transvenous implantable cardioverter defibrillator (ICD), the same cannot be assumed for subcutaneous ICD (S-ICD), where DT is still recommended due to limited evidence. Purpose This study aims to compare the long-term outcomes of S-ICD recipients with and without DT, focusing on cause-specific mortality, especially sudden cardiac death (SCD), and the incidence of shocks. Methods We analyzed data from the HONEST cohort, which includes 4,924 patients who received an S-ICD between 2012 and 2019 across150 French centers. Clinical follow-up and remote monitoring were used to track outcomes, including overall death, cardiovascular (CV) death, sudden cardiac death (SCD), a composite of SCD and deaths from unknown causes, as well as the incidence of appropriate and inappropriate shocks. Vital status was confirmed via the National Institute of Statistics and Economic Studies database, which tracks all deaths in France. Causes of death were adjudicated and classified following ESC guidelines. Propensity score weighting was used to adjust for confounding variables in comparisons between patients with DT (S-ICD Testing (+)) and those without DT (S-ICD Testing (-)). database Results In the HONEST cohort, 82.6% of the 4,924 patients underwent DT at S-ICD implantation, with a high success rate of 97.3%. Patients without DT were generally older (51.2 vs. 49.6 years, SMD=0.107), had a lower LVEF (37.6 vs. 43.3%, SMD=0.343), and were more frequently receiving S-ICD for primary prevention (68.0 vs. 62.4%, SMD=0.118). Crude analysis suggested lower overall mortality with DT (10.6 vs. 13.6%, HR=0.68, 95% CI 0.55–0.84, p&amp;lt;0.001), though this association did not remain significant after propensity score weighting (HR=0.89, 95% CI 0.73–1.10, p=0.285). No significant differences were observed in cardiovascular mortality (5.34 vs. 8.15%, HR=0.80, 95% CI 0.61–1.05, p=0.112), SCD (0.12 vs. 0.59%, HR=0.82, 95% CI 0.44–1.50, p= .978), or the composite of SCD and unknown causes (2.56 vs. 2.71%, HR=0.74, 95% CI 0.54–1.02, p=0.066). Rates of appropriate (12.10 vs. 12.34%, HR=0.92, 95% CI 0.74–1.14, p=0.442) and inappropriate shocks (12.20 vs. 10.10%, HR=1.07, 95% CI 0.85–1.35, p=0.572) were also similar. Conclusions Routine DFT does not significantly impact long-term outcomes, including overall mortality, cardiovascular death, SCD, composite outcomes of SCD and unknown death, or the incidence of appropriate and inappropriate shocks in the general population of S-ICD recipients.

Subcutaneous implantable cardioverter defibrillator in patients with arrhythmogenic right ventricular cardiomyopathy: Results from an Italian multicenter registry

Introduction: The subcutaneous implantable cardioverter defibrillator (SICD) serves as an alternative to traditional transvenous implantable cardioverter defibrillators in patients who meet criteria for ICD implantation without concurrent need for cardiac pacing. Data on SICD extraction is limited. This study examines the rates of SICD extraction. Methods: A retrospective study of all patients who underwent SICD implantation between 2010 and 2022 at a single healthcare system was performed. The primary endpoint was rate of SICD extraction. Results: A total of 402 patients (67.4% male; 48.5 ± 14.4 years old) underwent SICD implantation. Of these, 158 (39.3%) were for primary prevention in patients with heart failure with reduced ejection fraction, 125 (31.1%) for secondary prevention of ventricular tachyarrhythmias, and 69 (17.2%) for primary prevention in patients with hypertrophic cardiomyopathy with high-risk features. 29 (7.2%) patients (86.2% male; 51.5 ±12.9 years old) underwent SICD extraction during a mean follow up of 4.5 years. The median length of time between implant and explant was 49.1 [26.7-64.9] months. The most common indications for SICD extraction were need for pacing (17.2%), infection (17.2%), inappropriate shocks due to oversensing (13.8%), and lead failure (10.3%). There were no significant differences in average age, sex, or comorbidity profile between those who did and did not necessitate SICD extraction (extraction: 51.5 ± 12.9 years; no extraction: 48.4 ± 14.5 years; p=0.26) (Table). Conclusions: In appropriately selected patients undergoing implantation of the SICD, the likelihood of needing the device extracted was low at only 7.2% over 4.5 years, with the most common indications for extraction being need for pacing and infection. Further work must be done to determine whether these results regarding rates of, and indications for, SICD extractions are transferrable to other health systems.