Radiofrequency catheter ablation of ventricular tachycardia in ischemic heart disease in light of current practice: a systematic review and meta-analysis of randomized controlled trials

Optimal cardiac rhythm during substrate mapping in scar-related ventricular tachycardia: Significance of wavefront direction on identifying critical sites

BACKGROUND

A rotational activation pattern (RAP) around the localized line of a conduction block often correlates with sites specific to the critical zones of ventricular tachycardia (VT). The wavefront direction during substrate mapping affects manifestation of the RAP and line of block.

OBJECTIVE

The purpose of this study was to investigate the most optimal cardiac rhythm for identifying RAP and line of block in substrate mapping.

METHODS

We retrospectively evaluated 71 maps (median 3205 points/map) in 46 patients (65 ± 15 years; 33% with ischemic cardiomyopathy) who underwent high-density substrate mapping and ablation of scar-related VT. Appearance of a RAP during sinus, right ventricular (RV)-paced, left ventricular (LV)-paced, and biventricular-paced rhythms was investigated.

RESULTS

RAP was identified in 24 of 71 maps (34%) in the region where wavefronts from a single direction reached but not in the region where wavefronts from multiple directions centripetally collided. The probability of identifying the RAP depended on scar location; that is, anteroseptal and inferoseptal, inferior and apical, and basal lateral RAPs were likely to be identified during sinus/atrial, RV-paced, and LV-paced rhythms, respectively. In 13 patients, the RAP was not evident in the baseline map but became apparent during remapping in the other rhythm, in which the wavefront reached the site earlier within the entire activation time.

CONCLUSION

The optimal rhythm for substrate mapping depends on the spatial distribution of the area of interest. A paced rhythm with pacing sites near the scar may facilitate the identification of critical VT zones.

Percutaneous mechanical support in catheter ablation of ventricular arrhythmias: hype or hope?

Catheter ablation (CA) has become an established treatment strategy for managing recurrent ventricular tachycardias (VTs) in patients with structural heart disease. In recent years, percutaneous mechanical circulatory support (PMCS) devices have been increasingly used intra-operatively to improve the ablation outcome. One indication would be rescue therapy for patients who develop haemodynamic deterioration during the ablation. However, more efforts are focused on identifying subjects who are at high risk of such deterioration and could benefit from the pre-emptive use of the PMCS. The third reason to use PMCS could be the inability to identify diffuse substrate, especially in non-ischaemic cardiomyopathy. This paper reviews available experiences using various types of PMCS in different clinical scenarios. Although PMCS allows mapping during VT, it does not significantly influence acute outcomes and not convincingly long-term outcomes. On the contrary, the complication rate appears to be higher in PMCS cohorts. Our data suggest that even in patients with severe left ventricular dysfunction, the substrate modification can be performed without the need for general anaesthesia and risk of haemodynamic decompensation. In end-stage heart failure associated with the electrical storm, implantation of a left ventricular assist device (or PMCS with a transition to the left ventricular assist device) might be the preferred strategy before CA. In high-risk patients who are not potential candidates for these treatment options, radiotherapy could be considered as a bail-out treatment of recurrent VTs. These approaches should be studied in prospective trials.

Outcomes of ventricular tachycardia ablation in patients with ischemic and non-ischemic cardiomyopathy: A propensity-score matched analysis

INTRODUCTION AND OBJECTIVES

Catheter ablation (CA) is effective in the treatment of ventricular tachycardia (VT). Although some observational data suggest patients with non-ischemic cardiomyopathy (NICM) have less favorable outcomes when compared to those with an ischemic etiology (ICM), direct comparisons are rarely reported. We aimed to compare the outcomes of VT ablation in a propensity-score matched population of ICM or NICM patients.

METHODS

Single-center retrospective study of consecutive patients undergoing VT ablation from 2012 to 2023. A propensity score (PS) was used to match ICM and NICM patients in a 1:1 fashion according to age, sex, left ventricular ejection fraction (LVEF), NYHA class, electrical storm (ES) at presentation, and previous endocardial ablation. The outcomes of interest were VT-free survival and all-cause mortality.

RESULTS

The PS yielded two groups of 71 patients each (mean age 63±10 years, 92% male, mean LVEF 35±10%, 36% with ES at presentation, and 23% with previous ablation), well matched for baseline characteristics. During a median follow-up of 2.3 (interquartile range IQR 1.3-3.8) years, patients with NICM had a significantly lower VT-free survival (53.5% vs. 69.0%, log-rank p=0.037), although there were no differences regarding all-cause mortality (22.5% vs. 16.9%, log-rank p=0.245). Multivariate analysis identified NICM (HR 2.34 [95% CI 1.32-4.14], p=0.004), NYHA class III/IV (HR 2.11 [95% CI 1.11-4.04], p=0.024), and chronic kidney disease (HR 2.23 [95% CI 1.25-3.96], p=0.006), as independent predictors of VT recurrence.

CONCLUSION

Non-ischemic cardiomyopathy patients were at increased risk of VT recurrence after ablation, although long-term mortality did not differ.

Catheter Ablation of Ventricular Tachycardia in Ischemic Heart Disease: What Is Known and New Perspectives

PURPOSE OF THE REVIEW

This review aims to evaluate current evidence regarding ventricular tachycardia ablation in patients with ischemic heart disease and explore novel approaches currently developing to improve procedural and long-term outcomes.

RECENT FINDINGS

Recently published trials (PARTITA, PAUSE-SCD, and SURVIVE-VT) have demonstrated the prognostic benefit of prophylactic ventricular tachycardia ablation compared to current clinical practice. Advanced cardiac imaging provides a valuable pre-procedural evaluation of the arrhythmogenic substrate, identifying ablation targets non-invasively. Advanced cardiac mapping techniques allow to better characterize arrhythmogenic substrate during ablation procedure. Emerging technologies like pulsed field ablation and ultra-low temperature cryoablation show promise in ventricular tachycardia ablation. Advancements in mapping techniques, ablation technologies, and pre-procedural cardiac imaging offer promise for improving ventricular tachycardia ablation outcomes in ischemic heart disease.

Management of patients with an electrical storm or clustered ventricular arrhythmias: a clinical consensus statement of the European Heart Rhythm Association of the ESC-endorsed by the Asia-Pacific Heart Rhythm Society, Heart Rhythm Society, and Latin-American Heart Rhythm Society

Electrical storm (ES) is a state of electrical instability, manifesting as recurrent ventricular arrhythmias (VAs) over a short period of time (three or more episodes of sustained VA within 24 h, separated by at least 5 min, requiring termination by an intervention). The clinical presentation can vary, but ES is usually a cardiac emergency. Electrical storm mainly affects patients with structural or primary electrical heart disease, often with an implantable cardioverter-defibrillator (ICD). Management of ES requires a multi-faceted approach and the involvement of multi-disciplinary teams, but despite advanced treatment and often invasive procedures, it is associated with high morbidity and mortality. With an ageing population, longer survival of heart failure patients, and an increasing number of patients with ICD, the incidence of ES is expected to increase. This European Heart Rhythm Association clinical consensus statement focuses on pathophysiology, clinical presentation, diagnostic evaluation, and acute and long-term management of patients presenting with ES or clustered VA.

Catheter Ablation of Ventricular Arrhythmia in Patients With an Implantable Cardioverter-Defibrillator: A Systematic Review and Meta-analysis

BACKGROUND

Implantable cardioverter-defibrillator (ICD) shocks are associated with higher rates of mortality and reduced quality of life. In this study we aimed to investigate the effectiveness of catheter ablation (CA) of ventricular tachycardia in patients with an ICD.

METHODS

An electronic literature search was conducted to identify randomized controlled trials that compared CA vs control. The primary outcomes were recurrence of ventricular arrhythmia (ventricular tachycardia or ventricular fibrillation) and mortality. Kaplan-Meier curves for these outcomes were digitized to obtain individual patient data, which were pooled in a 1-stage meta-analysis to determine hazard ratios (HRs) and 95% confidence intervals (CIs). Secondary outcomes included cardiac hospitalization, electrical storm, syncope, appropriate ICD therapies, appropriate ICD shocks, and inappropriate shocks. For these, study-level HRs or risk ratios were obtained and pooled in random effects meta-analyses. Subgroup analysis was performed for trials that investigated prophylactic CA (before or during ICD implantation).

RESULTS

Data on 9 studies and 1103 patients were retrieved. CA significantly reduced ventricular tachycardia/ventricular fibrillation recurrence compared with control (shared frailty HR, 0.63; 95% CI, 0.49-0.81; P < 0.001) but not mortality (shared frailty HR, 0.84; 95% CI, 0.57-1.23; P = 0.361). CA was associated with significantly lower rates of cardiac hospitalization, electrical storm, appropriate ICD therapies and shocks, but not syncope or inappropriate shocks. Subgroup analysis showed similar results for prophylactic CA except that no significant difference was observed for cardiac hospitalizations.

CONCLUSIONS

CA is associated with reduced ventricular arrhythmia recurrence, appropriate ICD therapies/shocks, electrical storm, and cardiac hospitalization, and might be effective in preventing future morbidity. Future trials are needed to support the continued benefit of these promising results, and to investigate the optimal timing of ablation.

A systematic review and meta-analysis comparing radiofrequency catheter ablation with medical therapy for ventricular tachycardia in patients with ischemic and non-ischemic cardiomyopathies

BACKGROUND

In patients with cardiomyopathy, radiofrequency catheter ablation (CA) for ventricular tachycardia (VT) is an adjunctive and alternative treatment option to long-term anti-arrhythmic drug therapy. We sought to compare CA with medical therapy for the management of VT in patients with ischemic and non-ischemic cardiomyopathies.

METHODS

MEDLINE, Cochrane, and ClinicalTrials.gov databases were evaluated for relevant studies.

RESULTS

Eleven studies with 2126 adult patients were included (711 in CA, 1415 in medical therapy). In the randomized controlled trial (RCT) analysis, CA reduced risk of recurrent VT (risk ratio (RR) 0.79 [95% CI 0.67 to 0.93], p = 0.005), ICD shocks (RR 0.64 [95% CI 0.45 to 0.89] p = 0.008), and cardiac hospitalizations (RR 0.76 [95% CI 0.63 to 0.92] p = 0.005). There was no difference in all-cause mortality (RR 0.94, p = 0.71). In combined RCT and observational study analysis, there was a trend for reduction in all-cause mortality (RR 0.75 [95% CI 0.55 to 1.02] p = 0.07). In subgroup analysis of studies with mean left ventricular ejection fraction (LVEF) < 35%, CA demonstrated reduction in mortality (RR 0.71, p = 0.004), ICD shocks (RR 0.63, p = 0.03), VT recurrence (RR 0.76, p = 0.004), and cardiac hospitalizations (RR 0.75, p = 0.02). The subgroup of early CA prior to ICD shocks demonstrated reduction in ICD shocks (RR 0.57, p < 0.001) and VT recurrence (RR 0.74, p = 0.01).

CONCLUSIONS

CA for VT demonstrated a lower risk of VT recurrence, ICD shocks, and hospitalization in comparison to medical therapy. The subgroups of early CA and LVEF < 35% demonstrated better outcomes.

Impact of early ventricular tachycardia ablation in patients with an implantable cardioverter-defibrillator: An updated systematic review and meta-analysis of randomized controlled trials

BACKGROUND

There is limited information on whether early catheter ablation (CA) for ventricular tachycardia (VT) is associated with better outcomes compared with alternative strategies in patients with implantable cardioverter-defibrillator (ICD).

OBJECTIVE

The purpose of this article was to assess the efficacy of early VT CA in patients with ICD.

METHODS

EMBASE, PubMed, and Cochrane were searched from inception to April 2022. Randomized controlled trials comparing the efficacy of early VT CA with control groups, both in patients with ICD, were included in the analysis. Data on effect estimates in individual studies were extracted and combined via random effects meta-analysis using the DerSimonian and Laird method, a generic inverse variance strategy.

RESULTS

Nine randomized controlled trials with 1106 patients (n = 1018, 92.1% with ischemic cardiomyopathy and n = 88, 7.9% with nonischemic cardiomyopathy) were evaluated. VT CA was associated with reduced VT recurrences (odds ratio [OR] 0.64; P = .007), appropriate ICD shocks (OR 0.53; P = .002), ICD therapies (OR 0.54; P = .002), and cardiovascular hospitalization (OR 0.67; P = .004). However, no significant differences were observed in terms of mortality rate, heart failure hospitalization, and quality of life between the early VT CA and control groups.

CONCLUSION

Early CA was beneficial in reducing VT burden and ICD therapies. However, it did not affect mortality rate and quality of life. Since most patients in the included studies presented with ischemic cardiomyopathy, further studies on nonischemic cardiomyopathy should be conducted to validate if early CA has similar outcomes.

Outcomes of early catheter ablation for ventricular tachycardia in adult patients with structural heart disease and implantable cardioverter-defibrillator: An updated systematic review and meta-analysis of randomized trials

Aims

Catheter ablation (CA) for ventricular tachycardia (VT) can improve outcomes in patients with ischemic cardiomyopathy. Data on patients with non-ischemic cardiomyopathy are scarce. The purpose of this systematic review and meta-analysis is to compare early CA for VT to deferred or no ablation in patients with ischemic or non-ischemic cardiomyopathy.

Methods and results

Studies were selected according to the following PICOS criteria: patients with structural heart disease and an implantable cardioverter-defibrillator (ICD) for VT, regardless of the antiarrhythmic drug treatment; intervention–early CA; comparison–no or deferred CA; outcomes–any appropriate ICD therapy, appropriate ICD shocks, all-cause mortality, VT storm, cardiovascular mortality, cardiovascular hospitalizations, complications, quality of life; published randomized trials with follow-up ≥12 months. Random-effect meta-analysis was performed. Outcomes were assessed using aggregate study-level data and reported as odds ratio (OR) or mean difference with 95% confidence intervals (CIs). Stratification by left ventricular ejection fraction (LVEF) was also done. Eight trials (n = 1,076) met the criteria. Early ablation was associated with reduced incidence of ICD therapy (OR 0.53, 95% CI 0.33–0.83, p = 0.005), shocks (OR 0.52, 95% CI 0.35–0.77, p = 0.001), VT storm (OR 0.58, 95% CI 0.39–0.85, p = 0.006), and cardiovascular hospitalizations (OR 0.67, 95% CI 0.49–0.92, p = 0.01). All-cause and cardiovascular mortality, complications, and quality of life were not different. Stratification by LVEF showed a reduction of ICD therapy only with higher EF (high EF OR 0.40, 95% CI 0.20–0.80, p = 0.01 vs. low EF OR 0.62, 95% CI 0.34–1.12, p = 0.11), while ICD shocks (high EF OR 0.54, 95% CI 0.25–1.15, p = 0.11 vs. low EF OR 0.50, 95% CI 0.30–0.83, p = 0.008) and hospitalizations (high EF OR 0.95, 95% CI 0.58–1.58, p = 0.85 vs. low EF OR 0.58, 95% CI 0.40–0.82, p = 0.002) were reduced only in patients with lower EF.

Conclusion

Early CA for VT in patients with structural heart disease is associated with reduced incidence of ICD therapy and shocks, VT storm, and hospitalizations. There is no impact on mortality, complications, and quality of life. (The review protocol was registered with INPLASY on June 19, 2022, #202260080).

Systematic review registration

[https://inplasy.com/], identifier [202260080].