Emergent role of dynamic optimization in cardiac resynchronization therapy: Systematic review and network meta-analysis.

AIMS: Suboptimal device programming is frequent in non-responders to cardiac resynchronization therapy (CRT). However, the role of device optimization and the most appropriate technique are still unknown. The aim of our study was to analyse the effect of different CRT optimization techniques within a network meta-analysis. METHODS: A systematic search was conducted on MEDLINE, Embase and CENTRAL for studies comparing outcomes with empirical device settings or optimization using echocardiography, static algorithms or dynamic algorithms. Studies investigating the effect of optimization in non-responders were also analysed. RESULTS: A total of 17 studies with 4346 patients were included in the quantitative analysis. Of the treatments and outcomes examined, a significant difference was found only between dynamic algorithms and echocardiography, with the former leading to a higher echocardiographic response rate [odds ratio (OR): 2.02, 95% confidence interval (CI) 1.21-3.35], lower heart failure hospitalization rate (OR: 0.75, 95% CI 0.57-0.99) and greater improvement in 6-minute walk test [mean difference (MD): 45.52 m, 95% credible interval (CrI) 3.91-82.44 m]. We found no significant difference between empirical settings, static algorithms and dynamic algorithms. Seven studies with 228 patients reported response rates after optimization in non-responders. Altogether, 34.3%-66.7% of initial non-responders showed improvement after optimization, depending on response criteria. CONCLUSIONS: At the time of CRT implantation, dynamic algorithms may serve as a resource-friendly alternative to echocardiographic optimization, with similar or better mid-term outcomes. However, their superiority over empirical device settings needs to be investigated in further trials. For non-responders, CRT optimization should be considered, as the majority of patients experience improvement.

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

BACKGROUND: The subcutaneous implantable cardioverter-defibrillator (S-ICD) has emerged as an alternative to transvenous systems for prevention of sudden cardiac death. However, concerns have been raised regarding its efficacy and safety in obese individuals. OBJECTIVE: The purpose of this study was to perform a meta-analysis to evaluate the efficacy and safety of the S-ICD in patients with obesity by assessing the relationship between body mass index (BMI) and clinical outcomes. METHODS: A comprehensive search of multiple databases was conducted for English-language peer-reviewed studies reporting clinical outcomes in S-ICD recipients with (BMI ≥30 kg/m2) and without obesity (BMI <30 kg/m2). Data on preimplantation screening failure, defibrillation testing, complications, appropriate and inappropriate shocks, and survival were analyzed using standard, random-effects, meta-analytical techniques. RESULTS: Twenty-nine studies involving 20,486 patients were included. There was no statistically significant difference in mean BMI values of patients with failed or successful preimplantation screening (mean difference -0.60 kg/m2; 95% confidence interval [CI] -2.06 to 0.86). Obesity was associated with higher rates of failed defibrillation testing at ≤65 J (odds ratio [OR] 2.16; 95% CI 1.39-3.35), and malpositioning/suboptimal positioning occurred more frequently in obese compared to nonobese patients (OR 3.37; 95% CI 1.76-6.44). Increased BMI as a continuous variable (per increase in 1 kg/m2 BMI) was associated with elevated defibrillation thresholds (OR 1.05; 95% CI 1.03-1.08); higher risk of complications (hazard ratio [HR] 1.04; 95% CI 1.02-1.05); a trend toward an increased number of appropriate shocks (HR 1.02; 95% CI 1.00-1.04); and no significant increase in the risk of inappropriate shocks (HR 1.01; 95% CI 0.99-1.03). CONCLUSION: This meta-analysis underscores the importance of considering obesity in S-ICD implantation decisions. Although S-ICD remains effective in obese patients, attention to potential technical challenges and higher complication rates is warranted.

Risk of Cardiac Implantable Electronic Device Infection after Early versus Delayed Lead Repositioning.

(1) Background: Early reintervention increases the risk of infection of cardiac implantable electronic devices (CIEDs). Some operators therefore delay lead repositioning in the case of dislocation by weeks; however, there is no evidence to support this practice. The aim of our study was to evaluate the impact of the timing of reoperation on infection risk. (2) Methods: The data from consecutive patients undergoing lead repositioning in two European referral centers were retrospectively analyzed. The odds ratio (OR) of CIED infection in the first year was compared among patients undergoing early (≤1 week) vs. delayed (>1 week to 1 year) reoperation. (3) Results: Out of 249 patients requiring CIED reintervention, 85 patients (34%) underwent an early (median 2 days) and 164 (66%) underwent a delayed lead revision (median 53 days). A total of nine (3.6%) wound/device infections were identified. The risk of infection was numerically lower in the early (1.2%) vs. delayed (4.9%) intervention group yielding no statistically significant difference, even after adjustment for typical risk factors for CIED infection (adjusted OR = 0.264, 95% CI 0.032-2.179, p = 0.216). System explantation/extraction was necessary in seven cases, all being revised in the delayed group. (4) Conclusions: In this bicentric, international study, delayed lead repositioning did not reduce the risk of CIED infection.

Evaluating the predictive value of late gadolinium enhancement assessed by cardiac magnetic resonance on sudden cardiac death in patients selected for implantable cardioverter defibrillator and cardiac resynchronization therapy implantation: a systematic review and meta-analysis.

AIMS: Late gadolinium enhancement (LGE) assessed by cardiovascular magnetic resonance (CMR) can evaluate myocardial scar associated with a higher risk of sudden cardiac death (SCD), which can guide the selection between cardiac resynchronization therapy with or without a defibrillator (CRT-P/CRT-D). Our aim was to investigate the association between LGE and SCD risk in patients with CRT using the LGE-CMR technique. METHODS AND RESULTS: We performed a systematic literature search using four databases. The target population was CRT candidates. The primary endpoint was SCD. The risk of bias was assessed using the QUIPS tool. Fifteen eligible articles were included with a total of 2494 patients, of whom 27%, 56%, and 19% had an implantable cardioverter defibrillator (ICD), CRT-D, and CRT-P, respectively. Altogether, 54.71% of the cohort was LGE positive, who had a 72% higher risk for SCD (HR 1.72; 95% CI 1.18-2.50) compared to LGE negatives. In non-ischemic patients, the proportion of LGE positivity was 46.6%, with a significantly higher risk for SCD as compared to LGE negatives (HR 2.42; 95% CI 1.99-2.94). The subgroup of CRT-only patients showed no difference between the LGE-positive vs. negative candidates (HR 1.17; 95% CI 0.82-1.68). Comparable SCD risk was observed between articles with short- (OR 7.47; 95% CI 0.54-103.12) vs. long-term (OR 6.15; 95% CI 0.96-39.45) follow-up time. CONCLUSION: LGE-CMR positivity was associated with an increased SCD risk; however, in CRT candidates, the difference in risk reduction between LGE positive vs. negative patients was statistically not significant, suggesting a role of reverse remodeling. LGE-CMR before device implantation could be crucial in identifying high-risk patients even in non-ischemic etiology.

Indications for mexiletine in the new ESC guidelines and beyond.

INTRODUCTION: Mexiletine is a class IB sodium-channel blocker. Unlike class IA or IC antiarrhythmic drugs, mexiletine rather shortens than prolongs action potential duration; therefore, it is less associated with proarrhythmic effects. AREAS COVERED: Recently, new European Guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death were published, including a reappraisal of some established older antiarrhythmic drugs. EXPERT OPINION: Mexiletine offers a first-line, genotype-specific treatment strategy for LQT3 patients as emphasized by the most recent guidelines. Besides this recommendation, current study reports suggest that in therapy-refractory ventricular tachyarrhythmias and electrical storms adjunctive mexiletine treatment may offer the possibility of stabilizing patients with or without concomitant interventional therapy such as catheter ablation.

A head-to-head comparison of laser vs. powered mechanical sheaths as first choice and second line extraction tools.

AIMS: During transvenous lead extraction (TLE) longer dwelling time often requires the use of powered sheaths. This study aimed to compare outcomes with the laser and powered mechanical tools. METHODS AND RESULTS: Single-centre data from consecutive patients undergoing TLE between 2012 and 2021 were retrospectively analysed. Efficacy and safety of the primary extraction tool were compared. Procedures requiring crossover between powered sheaths were also analysed. Moreover, we examined the efficacy of each level of the stepwise approach. Out of 166 patients, 142 (age 65.4 ± 13.7 years) underwent TLE requiring advanced techniques with 245 leads (dwelling time 9.4 ± 6.3 years). Laser sheaths were used in 64.9%, powered mechanical sheaths in 35.1% of the procedures as primary extraction tools. Procedural success rate was 85.5% with laser and 82.5% with mechanical sheaths (P = 0.552). Minor and major complications were observed in similar rate. Procedural mortality occurred only in the laser group in the case of three patients. Crossover was needed in 19.5% after laser and in 12.8% after mechanical extractions (P = 0.187). Among crossover procedures, only clinical success favoured the secondary mechanical arm (87.1 vs. 54.5%, aOR: 0.09, 95% CI: 0.01-0.79, P = 0.030). After step-by-step efficacy analysis, procedural success was 64.9% with the first-line extraction tool, 75.1% after crossover, 84.5% with bailout femoral snare, and 91.8% by non-emergency surgery. CONCLUSION: The efficacy and safety of laser and mechanical sheaths were similar, however in the subgroup of crossover procedures mechanical tools had better performance regarding clinical success. Device diversity seems to help improving outcomes, especially in the most complicated cases.

Reimplantation and long-term mortality after transvenous lead extraction in a high-risk, single-center cohort.

PURPOSE: The use of cardiac implantable electronic devices (CIEDs) has increased significantly over the last decades. With the development of transvenous lead extraction (TLE), procedural success rates also improved; however, data regarding long-term outcomes are still limited. The aim of our study was to analyze the outcomes after TLE, including reimplantation data, all-cause and cause-specific mortality. METHODS: Data from consecutive patients undergoing TLE in our institution between 2012 and 2020 were retrospectively analyzed. Periprocedural, 30-day, long-term, and cause-specific mortalities were calculated. We examined the original and the revised CIED indications and survival rate of patients with or without reimplantation. RESULTS: A total of 150 patients (age 66 ± 14 years) with 308 leads (dwelling time 7.8 ± 6.3 years) underwent TLE due to pocket infection (n = 105, 70%), endocarditis (n = 35, 23%), or non-infectious indications (n = 10, 7%). All-cause mortality data were available for all patients, detailed reimplantation data in 98 cases. Procedural death rate was 2% (n = 3), 30-day mortality rate 2.6% (n = 4). During the 3.5 ± 2.4 years of follow-up, 44 patients died. Arrhythmia, as the direct cause of death, was absent. Cardiovascular cause was responsible for mortality in 25%. There was no significant survival difference between groups with or without reimplantation (p = 0.136). CONCLUSIONS: Despite the high number of pocket and systemic infection and long dwelling times in our cohort, the short- and long-term mortality after TLE proved to be favorable. Moreover, survival without a new device was not worse compared to patients who underwent a reimplantation procedure. Our study underlines the importance of individual reassessment of the original CIED indication, to avoid unnecessary reimplantation.