Concomitant thoracoscopic left cardiac sympathectomy and RVOT epicardial ablation of the arrhythmogenic substrate in a patient with Long QT and Brugada syndromes related to uncommon sodium channel beta-subunit mutation

Implantable Cardioverter-Defibrillator Therapy in Brugada Syndrome: A 30-Year Single-Center Experience

BACKGROUND

Brugada syndrome (BrS) continues to pose clinical challenges, despite 3 decades of dedicated research and therapeutic advancements. The pivotal role of implantable cardioverter-defibrillator (ICD) therapy in safeguarding high-risk BrS patients from sudden cardiac death due to ventricular arrhythmias is undeniable. However, the debate on risk stratification and the use of ICDs for primary prevention remains ongoing.

OBJECTIVES

This study aimed to evaluate the clinical features, management, and long-term outcomes of ICD therapy in patients with Brugada syndrome.

METHODS

BrS-diagnosed patients were prospectively enrolled. Inclusion criteria were: 1) a Brugada type 1 electrocardiogram pattern, either spontaneous or drug induced; 2) ICD implantation; and 3) consistent follow-up. Risk stratification was based on prior arrhythmic events, and the multiparametric Brussel risk score was used from 2017. High-risk patients underwent video-thoracoscopic epicardial ablation starting in 2016. ICD implantation strategies evolved over time, guided by patients' clinical and demographic characteristics.

RESULTS

A total of 306 consecutive Brugada patients (186 male [61%]; mean age 41 ± 17 years; range: 1-82 years) received ICDs at our institution from 1992 to 2022. ICDs were implanted for secondary prevention in 16% of patients. Over the 3 decades, the proportions of secondary prevention implants and asymptomatic patients remained stable, while risk factors fluctuated in the first two decades before stabilizing. During long-term follow-up (median 103 months [63-147 months]), 14% of patients experienced at least 1 sustained ventricular arrhythmia (VA) (1.59 per 100 person-years), 15% had at least 1 inappropriate ICD shock-unaffected by the presence of single or dual leads-and 27% required device revision and/or lead replacement. Patients with secondary prevention ICDs had a higher incidence of both ventricular and supraventricular arrhythmias compared to those with primary prevention ICDs. Loss-of-function mutations and prior nonsustained VAs were associated with sustained VAs. Among high-risk patients, those who underwent epicardial ablation experienced significantly fewer ventricular events. The overall mortality rate was 5.88%, with 22.2% of deaths attributed to cardiac causes.

CONCLUSIONS

This 30-year study highlights ICD therapy's critical role in preventing fatal arrhythmias in Brugada syndrome, but also reveals frequent device-related complications, especially in younger patients. Thoracoscopic epicardial ablation significantly reduced VA in high-risk patients, offering a promising adjunctive therapy. These findings emphasize the need for individualized treatment strategies to balance the benefits of ICDs with their risks, and underscore the potential of ablation to improve long-term outcomes.

Efficacy and safety of catheter ablation for Brugada syndrome: an updated systematic review

BACKGROUND

Patients with Brugada syndrome (BrS) may experience recurrent ventricular arrhythmias (VAs). Catheter ablation is becoming an emerging paradigm for treatment of BrS.

OBJECTIVE

To assess the efficacy and safety of catheter ablation in BrS in an updated systematic review.

METHODS

We comprehensively searched the databases of Pubmed/Medline, EMBASE, and Cochrane Central Register of Controlled Trials from inception to 11th of August 2021.

RESULTS

Fifty-six studies involving 388 patients were included. A substrate-based strategy was used in 338 cases (87%), and a strategy of targeting premature ventricular complex (PVCs)/ventricular tachycardias (VTs) that triggered ventricular fibrillation (VF) in 47 cases (12%), with combined abnormal electrogram and PVC/VT ablation in 3 cases (1%). Sodium channel blocker was frequently used to augment the arrhythmogenic substrate in 309/388 cases (80%), which included a variety of agents, of which ajmaline was most commonly used. After ablation procedure, the pooled incidence of non-inducibility of VA was 87.1% (95% confidence interval [CI], 73.4-94.3; I2 = 51%), and acute resolution of type I ECG was seen in 74.5% (95% CI [52.3-88.6]; I2 = 75%). Over a weighted mean follow up of 28 months, 7.6% (95% CI [2.1-24]; I2 = 67%) had recurrence of type I ECG either spontaneously or with drug challenge and 17.6% (95% CI [10.2-28.6]; I2 = 60%) had recurrence of VA.

CONCLUSION

Catheter ablation appears to be an efficacious strategy for elimination of arrhythmias or substrate associated with BrS. Further study is needed to identify which patients stand to benefit, and optimal provocation protocol for identifying ablation targets.

Ablation therapy of postural orthostatic tachycardia syndrome, inappropriate sinus tachycardia and primary electrical diseases: new insights in invasive treatment options in severely symptomatic patients

Achieving the goal management of some arrhythmic syndromes can be challenging; medical treatment for inappropriate sinus tachycardia (IST) and postural orthostatic tachycardia syndrome (POTS) may be ineffective, necessitating multidisciplinary team treatment. Implantable defibrillator devices (ICDs), along with anti-arrhythmic drugs (AADs), remain the first-line treatment for primary electrical diseases that pose a risk of sudden cardiac death (SCD). Ablation of the arrhythmogenic substrate is not always suggested in patients with these pathologies, but it may be a valuable support for reducing arrhythmic burden, improving quality of life, and treating pathologies that are resistant to pharmacological treatment; however, this option is not often considered due to the potential risks associated with an invasive approach. Minimally invasive hybrid ablation in these syndromes, such as a hybrid thoracoscopic approach and the use of non-invasive mapping systems, reduces post-surgery complications and ensures the best possible outcome for the patient.