Arrhythmic Events in Brugada Syndrome: A Nationwide Israeli Survey of the Clinical Characteristics, Treatment; and Long-Term Follow-up (ISRABRU-VF).

BACKGROUND: Limited information exists about detailed clinical characteristics and management of the small subset of Brugada syndrome (BrS) patients who had an arrhythmic event (AE). OBJECTIVES: To conduct the first nationwide survey focused on BrS patients with documented AE. METHODS: Israeli electrophysiology units participated if they had treated BrS patients who had cardiac arrest (CA) (lethal/aborted; group 1) or experienced appropriate therapy for tachyarrhythmias after prophylactic implantable cardioverter defibrillator (ICD) implantation (group 2). RESULTS: The cohort comprised 31 patients: 25 in group 1, 6 in group 2. Group 1: 96% male, mean CA age 38 years (range 13-84). Nine patients (36%) presented with arrhythmic storm and three had a lethal outcome; 17 (68%) had spontaneous type 1 Brugada electrocardiography (ECG). An electrophysiology study (EPS) was performed on 11 patients with inducible ventricular fibrillation (VF) in 10, which was prevented by quinidine in 9/10 patients. During follow-up (143 ± 119 months) eight patients experienced appropriate shocks, none while on quinidine. Group 2: all male, age 30-53 years; 4/6 patients had familial history of sudden death age < 50 years. Five patients had spontaneous type 1 Brugada ECG and four were asymptomatic at ICD implantation. EPS was performed in four patients with inducible VF in three. During long-term follow-up, five patients received ≥ 1 appropriate shocks, one had ATP for sustained VT (none taking quinidine). No AE recurred in patients subsequently treated with quinidine. CONCLUSIONS: CA from BrS is apparently a rare occurrence on a national scale and no AE occurred in any patient treated with quinidine.

Clinical and electrophysiologic outcomes of patients undergoing percutaneous endocardial ablation of scar-related ventricular tachycardia: a single-center experience.

BACKGROUND: For patients with ventricular tachyarrhythmias, implantable cardioverter defibrillators are a mainstay of therapy to prevent sudden death. However, ICD shocks are painful, can result in clinical depression, and do not offer complete protection against death from arrhythmia. Radiofrequency catheter ablation of ventricular tachycardia in the setting of ischemic cardiomyopathy has emerged recently as a useful adjunctive therapy to ICD. OBJECTIVES: To assess the feasibility, safety and efficacy of our initial experience in ablation of scar-related VT. METHODS: Eleven patients (all males, mean age 71 +/- 8 years) with drug-refractory ischemic VT were referred to our center for scar mapping and ablation procedures using the CARTO navigation system. RESULTS: Eleven clinical VTs (mean cycle length 436 +/- 93 ms) were induced in all patients. An endocardial circuit, identified by activation, entrainment and/or pace mapping, was found in eight patients with stable VT. These patients were mapped and ablated during VT. Three patients had predominantly unstable VT and linear ablation lesions were performed during sinus rhythm. Acute success, defined as termination of VT and/or non-inducibility during programmed electrical stimulation, was found in 9 patients (82%). During followup, a significant reduction in tachyarrythmia burden was observed in all patients who had successful initial ablation, except for one who had recurrence of VT 2 days after the procedure and died 2 weeks later. CONCLUSIONS: Ablation of ischemic VT using electroanatomic scar mapping is feasible, has an acceptable success rate and should be offered for ischemic patients with recurrent uncontrolled VT.

Importance of ventricular tachycardia storms not terminated by implantable cardioverter defibrillators shocks in patients with CASQ2 associated catecholaminergic polymorphic ventricular tachycardia.

In this study, the clinical and implantable cardioverter-defibrillator (ICD)-related follow-up of patients with catecholaminergic polymorphic ventricular tachycardia (CPVT) with homogenous missense mutations in CASQ2 was summarized. Patients were followed in a pediatric cardiology clinic and an ICD clinic. All patients were treated with high-dose ß blockers. ICDs were recommended for patients who remained symptomatic despite medical treatment. Twenty-seven patients were followed for 1 to 15 years (median 9). Twenty patients (74%) were symptomatic at diagnosis; 13 (65%) remained symptomatic after treatment with high-dose ß blockers and thus were advised to receive ICDs. Eight of these patients refused ICDs, and eventually 6 (75%) died suddenly. Four of the 5 patients who received ICDs had ventricular tachycardia storms treated but not terminated by recurrent ICD shocks. These ventricular tachycardia storms (2 episodes in 2 patients and 1 episode in 2 patient) terminated spontaneously after finishing the programmed ICD shocks, without degeneration to ventricular fibrillation. None of the patients who received ICDs died. In conclusion, patients with CASQ2-associated CPVT should be recommended to receive ICDs to prevent sudden death when medical therapy is not effective. These patients may have recurrent ventricular tachycardia storms treated but not terminated by recurrent ICD shocks, without degeneration to ventricular fibrillation.