Long-Term Trends in Newly Diagnosed Brugada Syndrome: Implications for Risk Stratification

Abstract

Background: A proband of Brugada syndrome (BrS) is the first patient diagnosed in a family. There are no data regarding this specific, high-risk population.

Objectives: This study sought to investigate the Brugada probands diagnosed from 1986 through the next 28 years.

Methods: We included 447 probands belonging to families with a diagnostic type 1 electrocardiogram Brugada pattern. The database was divided into 2 periods: the first period identified patients who were part of the initial cohort that became the consensus document on BrS in 2002 (early group); the second period reflected patients first diagnosed from 2003 to January 2014 (latter group).

Results: There were 165 probands in the early group and 282 in the latter group. Aborted sudden death as the first manifestation of the disease occurred in 12.1% of the early group versus 4.6% of the latter group (p = 0.005). Inducibility during programmed electrical stimulation was achieved in 34.4% and 19.2% of patients, respectively (p < 0.001). A spontaneous type 1 electrocardiogram pattern at diagnosis was present in 50.3% early versus 26.2% latter patients (p = 0.0002). Early group patients had a higher probability of a recurrent arrhythmia during follow-up (19%) than those of the latter group (5%) (p = 0.007). The clinical suspicion and use of a sodium-channel blocker to unmask BrS has allowed earlier diagnoses in many patients.

Conclusions: Since being first described, the presentation of BrS has changed. There has been a decrease in aborted sudden cardiac death as the first manifestation of the disease among patients who were more recently diagnosed. These variations in initial presentation have important clinical consequences. In this setting, the value of inducibility to stratify individuals with BrS has changed.

Keywords: electrophysiology; implantable cardioverter-defibrillator; sodium channel; sudden death; tachyarrhythmias.