High-risk atrioventricular block occurred in 2.7% of Brugada syndrome patients with syncope and was strongly associated with the presence of first-degree AVB (83% vs 15%; p=0.0005).
Cohort (n=223)
Yes
What are the clinical characteristics and incidence of high-risk atrioventricular block in Brugada syndrome patients with a history of syncope?
High-risk AVB is a rare but important cause of syncope in Brugada syndrome patients, particularly in those with baseline first-degree AVB, highlighting the need to consider bradyarrhythmias before ICD placement.
Absolute Event Rate: 83% vs 15%
p-value: p=0.0005
BACKGROUND: Determining the etiology of syncope is challenging in Brugada syndrome (BrS) patients. Implantable cardioverter defibrillator placement is recommended in BrS patients who are presumed to have arrhythmic syncope. However, arrhythmic syncope in BrS patients can occur in the setting of atrioventricular block (AVB), which should be managed by cardiac pacing. The clinical characteristics of BrS patients with high-risk AVB remain unknown. METHODS: This study included 223 BrS patients with a history of syncope from two centers. The clinical characteristics of patients with high-risk AVB (Mobitz type II second-degree AVB, high-degree AVB, or third-degree AVB) were investigated. RESULTS: During the 99 ± 78 months of follow-up, we identified six BrS patients (2.7%) with high-risk AVB. Three of the six patients (50%) with AVB presented with syncope associated with prodromes or specific triggers. Four patients (67%) were found to have paroxysmal third-degree AVB during the initial evaluation for BrS and syncope, while two patients developed third-degree AVB during the follow-up period. The incidence of first-degree AVB was significantly higher in AVB patients than in non-AVB patients (83% vs. 15%; p = .0005). There was no significant difference in the incidence of ventricular fibrillation between AVB and non-AVB patients (AVB 17%, non-AVB 12%; p = .56). CONCLUSION: High-risk AVB can occur in BrS patients with various clinical presentations. Although rare, the incidence is worth considering, especially in BrS patients with first-degree AVB.
Kamakura et al. (Fri,) conducted a cohort in Brugada syndrome with a history of syncope (n=223). High-risk atrioventricular block vs. Non-AVB was evaluated on First-degree AVB (p=0.0005). High-risk atrioventricular block occurred in 2.7% of Brugada syndrome patients with syncope and was strongly associated with the presence of first-degree AVB (83% vs 15%; p=0.0005).