Background—Five years ago, we described a specific ECG pattern of right bundle-branch block and ST-segment elevation in leads V₁ through V₃ associated with sudden death in patients without demonstrable structural heart disease. Information on long-term outcome has become available due to pooled data on a large cohort of patients with this syndrome who are followed at 33 centers worldwide.

Methods and Results—Data on 63 patients (57 men; mean age, 38±17 years) with the described ECG pattern were analyzed in terms of arrhythmic events and sudden death. Events were analyzed for patients with at least one episode of aborted sudden death or syncope of unknown origin before recognition of the syndrome (symptomatic patients, n=41) and for patients in whom the ECG pattern was recognized by chance or because of screening related to sudden death of a relative (asymptomatic patients, n=22). During a mean follow-up of 34±32 months, an arrhythmic event occurred in 14 symptomatic patients (34%) and 6 asymptomatic patients (27%). An automatic defibrillator was implanted in 35 patients, 15 received pharmacological therapy with β-blockers and/or amiodarone, and 13 did not receive treatment The incidence of arrhythmic events was similar in all therapy groups (log-rank 0.86); however, total mortality was 0% in the implantable defibrillator group, 26% in the pharmacological group, and 31% in the no therapy group (log-rank 0.0005). All mortality was due to sudden death.

Conclusions—Patients without demonstrable structural heart disease and an ECG pattern of right bundle-branch block and ST-segment elevation in leads V₁ through V₃ are at risk for sudden death. Amiodarone and/or β-blockers do not protect them against sudden death, and an implantable defibrillator seems to be the present treatment of choice.