Abstract 10241: Inferolateral Early Repolarization Syndrome Consists of Two Types of Sudden Death Syndrome Showing Different Clinical Profiles
Purpose: Although inferolateral early repolarization syndrome (ERS) excludes type-1 Brugada-type ECG according to Haïssaguerre et al., we previously reported that about 35% of patients with inferolateral ERS and a history of ventricular fibrillation (VF) showed saddleback ST elevation in the upper chest leads. We postulated that inferolateral ERS is a mixture of the sudden death syndrome with or without features of Brugada syndrome.
Methods: Drug provocation tests with a sodium channel blocker were conducted during standard and high costal (2nd and 3rd) ECG recordings in 25 inferolateral ERS patients with VF (23 males, mean age; 40.0 ± 13.9 years). Patients were put into 2 groups according to the results: the Brugada-like ERS group (BER: n=9) and the pure ERS group (PER: n=16). BER patients were defined as those with J waves in at least 2 inferolateral leads and type-2 or type-3 ST elevation in the upper chest leads, which never changes to type-1 even after drug test. PER patients were defined as those with only J waves. Clinical features were compared among 9 patients with BER, 16 patients with PER, 40 type-1 Brugada patients with prior VF (BS), and 13 patients with idiopathic VF and no J waves (IVF). Patients with arrhythmogenic hereditary syndrome, hypothermia, and organic heart disease were excluded from IVF. Mean follow-up for BER, PER, BS, and IVF groups was 89 ± 55, 58 ± 38, 104 ± 63, and 82 ± 50 months, respectively.
Results: VF was seen during sleep or near sleep in 8 of 9 (89%) patients with BER and in 22 of 40 (55%) with BS, but also in 1 of 16 (6%) patients with PER and in 1 of 13 (8%) with IVF (BER and BS vs PER, p<0.001). VF inducibility by electrical stimulation was 66% in BER, 81% in BS, 22% in PER, and 27% in IVF group. VF recurrence including electrical storm was significantly higher in patients with BER (56%), BS (55%), and BER with a J wave in lead I (57%), compared with PER (6%), where J waves were noted in the inferior or global leads in 13 of 16 cases, and IVF (15%) (VF recurrence; BER and BS vs PER; p<0.01).
Conclusions: Inferolateral ERS with VF comprises 2 subtypes with different clinical profiles. The BER group is similar to type-1 Brugada with poor outcome and the PER group is similar to IVF group with few arrhythmic events. The distribution of J waves was not prognostic in the PER group.
- © 2011 by American Heart Association, Inc.