Right Bundle-Branch Block and ST-Segment Elevation in Leads V1 Through V3
A Marker for Sudden Death in Patients Without Demonstrable Structural Heart Disease
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.
In 1992, we1 described eight cases of aborted sudden death in patients without demonstrable structural heart disease and a peculiar ECG pattern consisting of right bundle-branch block and ST-segment elevation in leads V1 to V3 (Fig 1⇓). Since then, new reports have appeared in the worldwide literature suggesting a more common than previously suspected disorder.2 3 4 5 In this article, we present the data and follow-up for a large cohort of patients with this ECG abnormality.
The population consisted of 56 men and 7 women with a mean age at the time of diagnosis of 38±17 years. Twenty-seven patients had a family history of sudden death, and 9 were family members of affected individuals. These patients have been identified in 33 centers around the world (“Appendix”). Only the patients in whom the physician definitively excluded demonstrable structural heart disease after extensive invasive and noninvasive tests were included. Noninvasive tests included enzymatic and electrolytic profile in all, echocardiogram in all, ergonovine test in 53 patients, stress test in 55 patients, and nuclear magnetic resonance imaging in 22 patients. Invasive test included coronary angiography in 49 patients, left ventriculography in 48 patients, right ventriculography in 43 patients, and endomyocardial biopsies in 17 patients. In none of these tests could structural heart disease be demonstrated, and all were informed as normal. Patients were treated depending on the physician preferences. Information about last follow-up was obtained from the primary physician.
A patient was considered to have an arrhythmic event if he or she had a documented episode of syncopal ventricular arrhythmia or sudden death or received an appropriate shock from an implantable defibrillator. Shocks were considered appropriate shocks when ventricular tachycardia or ventricular fibrillation was documented using the stored electrograms of the device or when syncope or dizziness preceded the shock if electrograms were not available.
The probability of survival and event-free analysis was estimated with the Kaplan-Meier method. The statistical significance of each comparison was calculated with the log-rank test. Cross-comparisons were done using χ2 analysis.
In 41 patients, the abnormal ECG pattern was first identified after an episode of aborted sudden death (n=32) or syncope of unknown origin (n=9) (symptomatic patients). In 12 of the 32 patients with aborted sudden death, a previous history of recurrent sincopal episodes was present before the cardiac arrest. In two of these patients, nonsustained polymorphic ventricular tachycardia was documented during such episodes. In the remaining 22 patients, the abnormal ECG was identified during routine ECG (n=13) or during screening after an episode of sudden death in a family member (n=9) (asymptomatic patients). All patients were not taking drugs when the abnormal ECG was identified. During follow-up, 6 of these 22 asymptomatic patients developed symptoms (4, sudden death; 2, aborted sudden death). Therefore, 47 of the 63 patients have developed symptoms at least once in their lifetime. The age of first arrhythmic event ranged from 2 to 77 years, with a mean age of 41±18 years.
In 46 of the 63 patients, programmed ventricular stimulation while off drugs was performed. Because patients were seen at different centers, the stimulation protocol that was used was not uniform. However, in all cases, up to three ventricular extrastimuli were used in at least one right ventricular site. In 37 of the 46 patients (80%), ventricular fibrillation (n=30) or long runs (>10 seconds) of nonsustained polymorphic ventricular tachycardia (n=7) were repeatedly induced with one (n=2), two (n=19), or three (n=16) premature ventricular stimuli. Inducibility was similar in symptomatic (25 of 32) and asymptomatic (12 of 14) patients (P=NS).
Treatment was decided by the primary physician and could be not randomized at that time. Thirty-five patients received an implantable defibrillator, 15 patients received pharmacological treatment (β-blockers and/or amiodarone), and 13 patients had no therapy. Patients who received a defibrillator were more often symptomatic and inducible at the electrophysiological study (Table 1⇓). During a mean follow-up of 34±32 months, an arrhythmic event was detected in 11 patients with an implantable defibrillator (31%) (Fig 2⇓), 5 patients in the pharmacological group (33%), and 4 patients in the no therapy group (31%) (P=NS). No patient died in the implantable defibrillator group, 4 patients died in the pharmacological group, and 4 patients died in the no therapy group (P<.002). All mortality was due to sudden death. In Figs. 3⇓ and 4⇓, the Kaplan-Meier curves are shown for recurrent arrhythmic events and mortality depending on the therapy group. No variable was found to be predictable for a recurrent arrhythmic event (Table 2⇓).
In Fig 5⇓, Kaplan-Meier curves of recurrent arrhythmic event in symptomatic patients are compared with the first arrhythmic event in asymptomatic patients. During a mean follow-up of 37±31 months, 14 of the 41 symptomatic patients had recurrent arrhythmic events compared with 6 of 22 asymptomatic patients who developed symptoms (P=NS) during a mean follow-up of 27±32 months.
In this study, we present data on 63 patients recruited in 33 centers around the world in whom an abnormal ECG was documented consisting of right bundle-branch block and ST-segment elevation in leads V1 to V3. We have previously shown that the administration of IV ajmaline or procainamide can unmask the presence of such an ECG pattern in patients previously recognized with the abnormal ECG but with transient normalization or in family members of affected individuals.6 7 Because we do not know whether these patients are similar to those in whom the abnormal ECG is documented spontaneously without pharmacological intervention, in the present series only those with a basal off-drugs abnormal ECG were included to have an homogeneous group of patients. Some patients underwent extensive noninvasive and invasive evaluation, specially the symptomatic ones, whereas others (specially the asymptomatic ones) underwent a more limited evaluation including, however, in all cases, at least an echocardiogram; in most cases, a stress test and an ergonovine test; and in a large group, coronary angiography, left and right ventriculography, and electrophysiological study. Because not all tests were performed in all patients, we cannot exclude that some minor forms of structural heart disease might have remained undiagnosed. However, the fact that follow-up failed to show any progression to some form of right or left cardiomyopathy argues against it.
The present data show that patients with no demonstrable structural heart disease and an abnormal ECG pattern consisting of right bundle-branch block and ST-segment elevation in leads V1 through V3 are at risk of sudden death. Most patients were first identified after an episode of aborted sudden death. In this group, incidence of recurrent arrhythmic events during follow-up was 34%, similar to the incidence described in survivors of idiopathic ventricular fibrillation.8 However, asymptomatic patients in whom the abnormal ECG was identified during routine ECG test or family screening had also an incidence of arrhythmic events during follow-up of 27%. These results strongly stress the need for careful evaluation of asymptomatic patients with this ECG pattern and the need for family ECG screening in survivors of cardiac arrest. With the present data, an abnormal ECG like the one described should be considered a marker of high risk of sudden death during follow-up and careful evaluation of the need for therapy should be done. Mortality rate is very high in patients treated with pharmacological agents such as amiodarone and β-blockers, but no mortality occurred in patients with an implantable defibrillator. Follow-up of patients with an implantable defibrillator has shown a high incidence of recurrent arrhythmic events appropriately treated by the device; this justifies the implantation of such a device in all patients with the ECG described despite the uncertainties associated with the pathophysiology of the syndrome.
In conclusion, patients with the abnormal ECG consisting on right bundle-branch block and ST-segment elevation in leads V1 to V3 and without demonstrable structural heart disease are at high risk for sudden death. Asymptomatic patients with the ECG anomaly have the same risk of arrhythmic events as do patients who have had an episode of aborted sudden death. Pharmacological treatment with amiodarone and/or β-blockers does not protect patients against sudden arrhythmic death, and an implantable defibrillator is at present the treatment of choice.
Physicians and Centers
A. Asso, Hospital Miguel Servet, Zaragoza, Spain; J. Atié, Universidad Federal Rio de Janeiro, Brasil; J. Brugada, L. Mont, Hospital Clínic, Universidad de Barcelona, Spain; P. Brugada, OLV Hospital, Aalst, Belgium; J. Cabrera, Hospital NaSra. del Pino, Las Palmas, Spain; J.R. Carmona, Hospital de Navarra, Pamplona, Spain; J.P. Cebron, Saint Henri Hospital, Nantes, France; L. De Roy, Mont-Godine Hospital, Yvoir, Belgium; P. Della Bella, Università degli Studi di Milano, Italy; A. Ebagosti, CHG Martigues, France; J. Farré, Fundación Jimenez Diaz, Madrid, Spain; M. Fromer, CHU Vaudois, Lausanne, Switzerland; R. Hauer, University Hospital Utrecht, The Netherlands; C. Lafuente, Hospital General Albacete, Spain; J. Martinez, F. Picó, Hospital Virgen de la Arrixaca, Murcia, Spain; J. Metzger, Hopital Cantonal, Geneva, Switzerland; C. Moro, Hospital Ramón y Cajal, Madrid, Spain; A. Moya, Hospital Vall d’Hebró, Barcelona, Spain; J. Ollitrault, Hospital Saint Joseph, Paris, France; M. Pavón, Hospital Virgen de la Macarena, Sevilla, Spain; J. Pelegrin, Hospital Clínico Zaragoza, Spain; D. Potenza, San Giovanni Rotondo, Italy; S. Priori, Università di Milano, Italy; J. Rodriguez, Hospital Virgen de Valme, Sevilla, Spain; X. Sabaté, Hospital Bellvitge, Barcelona, Spain; P. Scanu, CHU Caen, France; E. Sosa, INCOR, Sao Paolo, Brasil; W. Stevenson, Brigham and Women’s Hospital, Boston, Mass; R. Stroobandt, St Jozef Hospital, Oostende, Belgium; V. Taramasco, CHU Marseille, France; J.K. Triedman, Children’s Hospital, Boston, Mass; P. Vanzini, Asociación Española, Montevideo, Uruguay; J. Villacastin, Hospital Gregorio Marañon, Madrid, Spain.
- Received September 18, 1997.
- Accepted October 13, 1997.
- Copyright © 1998 by American Heart Association
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