| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
(Circulation. 2003;108:3092-3096.)
© 2003 American Heart Association, Inc.
Clinical Investigation and Reports |
From the Arrhythmia Section, Cardiovascular Institute, Hospital Clínic, University of Barcelona, Spain (J.B.); the Masonic Medical Research Laboratory, Utica, New York (R.B.); and the Cardiovascular Research and Teaching Institute, Aalst, Belgium (P.B.).
Correspondence to Josep Brugada, MD, PhD, Arrhythmia Section, Cardiovascular Institute, Hospital Clínic, University of Barcelona, Villarroel 170, 08036 Barcelona, Spain. E-mail jbrugada{at}clinic.ub.es
Received March 6, 2003; de novo received July 9, 2003; revision received September 12, 2003; accepted September 18, 2003.
| Abstract |
|---|
|
|
|---|
Methods and Results A total of 547 patients with an ECG diagnostic of Brugada syndrome and no previous cardiac arrest were studied. The mean age was 41±15 years, and 408 were male. The diagnostic ECG was present spontaneously in 391 patients. In the remaining 156 individuals, the abnormal ECG was noted only after the administration of an antiarrhythmic drug. One hundred twenty-four patients had suffered from at least 1 episode of syncope. During programmed ventricular stimulation, a sustained ventricular arrhythmia was induced in 163 of 408 patients. During a mean follow-up of 24±32 months, 45 patients (8%) suffered sudden death or documented ventricular fibrillation. Multivariate analysis identified the inducibility of a sustained ventricular arrhythmia (P<0.0001) and a history of syncope (P<0.01) as predictors of events. Logistic regression analysis showed that a patient with a spontaneously abnormal ECG, a previous history of syncope, and inducible sustained ventricular arrhythmias had a probability of 27.2% of suffering an event during follow-up.
Conclusions Individuals with Brugada syndrome and no previous cardiac arrest have a high risk of sudden death. Inducibility of ventricular arrhythmias and a previous history of syncope are markers of a poor prognosis.
Key Words: fibrillation sudden death electrocardiography arrhythmia genetics
| Introduction |
|---|
|
|
|---|
| Methods |
|---|
|
|
|---|
0.2 mV, with a slowly descending ST segment in continuation with a flat or negative T wave (coved-type ECG) appeared spontaneously in leads V1 to V3 (Figure 1). The ECG was also defined as abnormal when the described ECG abnormalities became evident after the intravenous administration of an antiarrhythmic drug with potent sodium-channel blocking properties, such as ajmaline, flecainide, or procainamide.11 Structural heart disease was excluded by clinical history, noninvasive methods (echocardiogram, stress test, nuclear magnetic resonance), and invasive methods (coronary angiography, left and right ventriculography, and myocardial biopsies) used at the discretion of the treating physician.
|
The abnormal ECG was identified during the investigation of syncope of unknown origin in 124 patients, during routine ECG screening in 170 individuals and during study of family members of patients with the syndrome in 253 individuals.
Electrophysiological study included basal measurements of conduction intervals and programmed ventricular stimulation. The protocol recommended used a single site of stimulation (right ventricular apex), 3 basic pacing cycles (600, 500, and 430 ms), and induction of 1, 2, and 3 ventricular premature beats down to a minimum of 200 ms. A patient was considered inducible if a sustained ventricular arrhythmia (ventricular fibrillation, polymorphic ventricular tachycardia, or monomorphic ventricular tachycardia lasting >30 seconds or requiring emergency intervention) was induced.
Statistical Analysis
Data were analyzed by use of the STATA Statistical Software (StataCorp., 1999, 7.0). The Fisher exact test or the
2 test was used for categorical variables. One-way ANOVA was used for comparisons of continuous variables among the different groups. Survival curves were plotted by the Kaplan-Meier method and analyzed by the log-rank test. Cox regression models were used to analyze factors associated with occurrence of events. The variables that were significant were used in a logistic regression model to predict the probability of having an event. A probability value of P<0.05 was considered statistically significant. Where applicable, data are presented as mean±SD.
| Results |
|---|
|
|
|---|
|
Follow-Up
The individuals were followed up prospectively for a mean of 24±33 months (range, 1 to 160 months) after the diagnostic ECG was recognized.
In 45 of the 547 individuals (8.2%), sudden cardiac death (16 patients) or ventricular fibrillation (29 patients) occurred during the follow-up period (Figure 2). By univariate analysis, inducibility of a sustained ventricular arrhythmia, a previous episode of syncope, a spontaneously abnormal ECG, and male sex were predictors of events (Table 2). Multivariate analysis identified inducibility of a sustained ventricular arrhythmia and a history of syncope as predictors of sudden death or ventricular fibrillation (Table 2). Figure 3 shows the Kaplan-Meier curves of arrhythmic events during follow-up depending on the presence of a previous history of syncope and inducibility of arrhythmias during electrophysiological study.
|
|
|
By logistic regression analysis of these 2 variables and the presence or absence of a spontaneously abnormal ECG, 8 groups were identified with a risk of sudden death or documented ventricular fibrillation during follow-up varying from 0.5% to 27.2% (Table 3). The lowest-risk group is an individual with an ECG diagnostic of Brugada syndrome seen only after drug administration who is not inducible during programmed ventricular stimulation and who has no previous syncope. The highest-risk group included individuals with a spontaneously abnormal ECG who are inducible during programmed ventricular stimulation and have suffered at least 1 syncopal episode. The other risk categories are shown in Table 3.
|
| Discussion |
|---|
|
|
|---|
How the diagnosis was made in this population varied. In some individuals, a spontaneously abnormal ECG was recorded as part of a routine screening, for instance, before surgery or to obtain a license for competitive sports. In others, it was observed after an episode of syncope of unknown origin. In still others, the abnormal ECG was observed because of a family history of sudden death or Brugada syndrome. In this last case, the abnormal ECG appeared in some individuals only during the administration of a sodium channel blocker to identify carriers of the disease within the family. Finally, in some individuals, the diagnostic ECG was seen during treatment with antiarrhythmic drugs given against atrial fibrillation or other cardiac arrhythmias.
The strongest predictor of outcome in patients with an ECG diagnostic of Brugada syndrome and no previous cardiac arrest is inducibility during programmed ventricular stimulation. Inducible individuals have a 6 times higher risk of suffering sudden death or ventricular fibrillation during the subsequent 2 years compared with noninducible individuals. The next best predictor was a previous history of syncope. Patients with a previous history of syncope have a 2.5 times higher risk than asymptomatic patients. Factors identified by univariate analysis, which were no longer predictive by multivariate analysis, included a spontaneously abnormal ECG and male sex. However, it has to be stressed that the prognostic value of programmed ventricular stimulation was highest in the group with no symptoms at all, i.e., without a previous history of syncope. Noninducible patients with a previous history of syncope still had an unacceptably high risk of (aborted) sudden arrhythmic death during the follow-up.
The implications of these observations can be very relevant for the daily management of individuals with Brugada syndrome and no previous cardiac arrest, as follows.
Individuals with a Brugada ECG and a previous history of syncope have a high risk for sudden death (27.2% in inducible patients but still 4.1% in noninducible patients at 2 years of follow-up with an upper 95% CI of 11.7%). Patients with a previous history of syncope probably do not require programmed ventricular stimulation for risk stratification. Implantation of a defibrillator in these patients seems to be as mandatory as it is in patients with resuscitated sudden arrhythmic death until other effective therapeutic alternatives become available.
Programmed ventricular stimulation should be performed in asymptomatic individuals to stratify the risk. Those inducible during programmed ventricular stimulation should undergo implantation of a defibrillator. Noninducible individuals should be followed up carefully and made aware of the risks of fever, antiarrhythmic drugs, and other possible triggers of ventricular arrhythmias in Brugada syndrome.
Limitations of the Study
The principal limitation in this study is the way in which patients were selected for drug challenge or electrophysiological study determined in part by physician expertise and biases. This may have affected the outcome of the study.
A second important limitation is the mean follow-up of only 24 months, which is too short a period to allow for definitive conclusions about the management of patients with Brugada syndrome. It is quite conceivable that in some groups of patients, prognosis might worsen as follow-up prolongs. Only with large numbers of patients and long-term follow-up can one meaningfully ascertain the magnitude of the risk and, in turn, determine whether the level of risk in noninducible patients is sufficiently low as to justify not implanting an ICD.
Finally, the use of the information collected from the electrograms stored in the ICD might cause some overestimation of the risk of sudden death. This is because of (1) the difficult differentiation between some supraventricular tachycardias and ventricular arrhythmias and (2) the presence of some ventricular arrhythmias that might not cause sudden death because they are either well-tolerated or self-limited. In our study, patients had either sudden death or documented ventricular fibrillation. This significantly diminished the bias: first, because ventricular fibrillation episodes almost never are misdiagnosed as supraventricular, and second, because it can be reasonably assumed that most, if not all, cases of ventricular fibrillation produce subsequent sudden death if not treated.
| Conclusions |
|---|
|
|
|---|
2 years. The lowest-risk group can be defined by the absence of syncopal episodes, a diagnostic ECG only after antiarrhythmic drug challenge, and noninducibility during programmed ventricular stimulation (0.5% incidence of events). The highest-risk group is defined by a combination of a previous history of syncope, a spontaneously abnormal ECG, and inducible sustained arrhythmias during programmed ventricular stimulation (27.2% incidence of events). | Appendix |
|---|
|
|
|---|
| Acknowledgments |
|---|
| References |
|---|
|
|
|---|
2. Miyasaka T, Tsuji H, Yamada K, et al. Prevalence and mortality of the Brugada-type electrocardiogram in one city in Japan. J Am Coll Cardiol. 2001; 38: 771774.
3. Brugada J, Brugada R, Brugada P. 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. Circulation. 1998; 97: 457460.
4. Brugada R, Brugada J, Antzelevitch C, et al. Sodium channel blockers identify risk for sudden death in patients with ST-segment elevation and right bundle-branch block but structurally normal hearts. Circulation. 2000; 101: 510515.
5. Brugada P, Geelen P, Brugada R, et al. Prognostic value of electrophysiologic investigations in Brugada syndrome. J Cardiovasc Electrophysiol. 2001; 12: 10041007.[CrossRef][Medline] [Order article via Infotrieve]
6. Brugada J, Brugada R, Antzelevitch C, et al. Long-term follow-up of individuals with the electrocardiographic pattern of right bundle-branch block and ST-segment elevation in precordial leads V1 to V3. Circulation. 2002; 105: 7378.
7. Priori SG, Napolitano C, Gasparini M, et al. Natural history of Brugada syndrome: insights for risk stratification and management. Circulation. 2002; 105: 13421347.
8. Boveda S, Albenque JP, Baccar H, et al. Prophylactic value of automatic implantable defibrillators: a case report of a patient with asymptomatic Brugada syndrome. Arch Mal Coeur Vaiss. 2001; 94: 7984.[Medline] [Order article via Infotrieve]
9. Takenada S, Kusano KF, Hisamatsu K, et al. Relatively benign course in asymptomatic patients with Brugada-type electrocardiogram without family history of sudden death. J Cardiovasc Electrophysiol. 2001; 12: 26.[CrossRef][Medline] [Order article via Infotrieve]
10. Wilde A, Antzelevitch C, Borggrefe M, et al. Proposed diagnostic criteria for the Brugada syndrome. Circulation. 2002; 106: 25142518.
11. Miyazaki T, Mitamura H, Miyoshi S, et al. Autonomic and antiarrhythmic drug modulation of ST segment elevation in patients with Brugada syndrome. J Am Coll Cardiol. 1996; 27: 10611070.[Abstract]
This article has been cited by other articles:
![]() |
S. Kamakura, T. Ohe, K. Nakazawa, Y. Aizawa, A. Shimizu, M. Horie, S. Ogawa, K. Okumura, K. Tsuchihashi, K. Sugi, et al. Long-Term Prognosis of Probands With Brugada-Pattern ST-Elevation in Leads V1-V3 Circ Arrhythm Electrophysiol, October 1, 2009; 2(5): 495 - 503. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Veltmann, C. Wolpert, F. Sacher, P. Mabo, R. Schimpf, F. Streitner, J. Brade, F. Kyndt, J. Kuschyk, H. Le Marec, et al. Response to intravenous ajmaline: a retrospective analysis of 677 ajmaline challenges Europace, October 1, 2009; 11(10): 1345 - 1352. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Veltmann, C. Wolpert, R. Schimpf, P. Mabo, H. LeMarec, M. Borggrefe, and V. Probst The ajmaline challenge and a strange ECG: reply Europace, October 1, 2009; 11(10): 1406 - 1407. [Full Text] [PDF] |
||||
![]() |
C. Pappone, A. Radinovic, F. Manguso, G. Vicedomini, S. Sala, F. M. Sacco, G. Ciconte, M. Saviano, M. Ferrari, E. Sommariva, et al. New-onset atrial fibrillation as first clinical manifestation of latent Brugada syndrome: prevalence and clinical significance Eur. Heart J., August 20, 2009; (2009) ehp326v1. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. P. Sidik, C. N. Quay, F. C. Loh, and L. Y. Chen Prevalence of Brugada sign and syndrome in patients presenting with arrhythmic symptoms at a Heart Rhythm Clinic in Singapore Europace, May 1, 2009; 11(5): 650 - 656. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Giustetto, S. Drago, P. G. Demarchi, P. Dalmasso, F. Bianchi, A. S. Masi, P. Carvalho, E. Occhetta, G. Rossetti, R. Riccardi, et al. Risk stratification of the patients with Brugada type electrocardiogram: a community-based prospective study Europace, April 1, 2009; 11(4): 507 - 513. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Benito, A. Sarkozy, L. Mont, S. Henkens, A. Berruezo, D. Tamborero, D. Arzamendi, P. Berne, R. Brugada, P. Brugada, et al. Gender Differences in Clinical Manifestations of Brugada Syndrome J. Am. Coll. Cardiol., November 4, 2008; 52(19): 1567 - 1573. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Francis and C. Antzelevitch Atrial Fibrillation and Brugada Syndrome J. Am. Coll. Cardiol., March 25, 2008; 51(12): 1149 - 1153. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Hayashi, S. Takatsuki, P. Maison-Blanche, A. Messali, A. Haggui, P. Milliez, A. Leenhardt, and F. Extramiana Ventricular Repolarization Restitution Properties in Patients Exhibiting Type 1 Brugada Electrocardiogram With and Without Inducible Ventricular Fibrillation J. Am. Coll. Cardiol., March 25, 2008; 51(12): 1162 - 1168. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Sarkozy, T. Boussy, G. Kourgiannides, G.-B. Chierchia, S. Richter, T. De Potter, P. Geelen, F. Wellens, M. D. Spreeuwenberg, and P. Brugada Long-term follow-up of primary prophylactic implantable cardioverter-defibrillator therapy in Brugada syndrome: reply Eur. Heart J., November 2, 2007; 28(22): 2820 - 2821. [Full Text] [PDF] |
||||
![]() |
E. A. Stephenson and C. I. Berul Electrophysiological Interventions for Inherited Arrhythmia Syndromes Circulation, August 28, 2007; 116(9): 1062 - 1080. [Full Text] [PDF] |
||||
![]() |
C. Veltmann, R. Schimpf, C. Echternach, L. Eckardt, J. Kuschyk, F. Streitner, S. Spehl, M. Borggrefe, and C. Wolpert A prospective study on spontaneous fluctuations between diagnostic and non-diagnostic ECGs in Brugada syndrome: implications for correct phenotyping and risk stratification Eur. Heart J., November 1, 2006; 27(21): 2544 - 2552. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Schulze-Bahr Arrhythmia Predisposition: Between Rare Disease Paradigms and Common Ion Channel Gene Variants J. Am. Coll. Cardiol., October 27, 2006; 48(9_Suppl_A): A67 - A78. [Abstract] [Full Text] [PDF] |
||||
![]() |
Developed in Collaboration With the European Heart, D. P. Zipes, A. J. Camm, M. Borggrefe, A. E. Buxton, B. Chaitman, M. Fromer, G. Gregoratos, G. Klein, A. J. Moss, et al. ACC/AHA/ESC 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death--Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death) J. Am. Coll. Cardiol., September 5, 2006; 48(5): 1064 - 1108. [Full Text] [PDF] |
||||
![]() |
Developed in Collaboration With the European Heart, D. P. Zipes, A. J. Camm, M. Borggrefe, A. E. Buxton, B. Chaitman, M. Fromer, G. Gregoratos, G. Klein, A. J. Moss, et al. ACC/AHA/ESC 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death: A Report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death) J. Am. Coll. Cardiol., September 5, 2006; 48(5): e247 - e346. [Full Text] [PDF] |
||||
![]() |
D. P. Zipes, D. P. Zipes, A. J. Camm, M. Borggrefe, A. E. Buxton, B. Chaitman, M. Fromer, G. Gregoratos, G. Klein, A. J. Moss, et al. ACC/AHA/ESC 2006 guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death--executive summary: A report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for Management of Patients with Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death) Developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society. Eur. Heart J., September 1, 2006; 27(17): 2099 - 2140. [Full Text] [PDF] |
||||
![]() |
Writing Committee Members, D. P. Zipes, A. J. Camm, M. Borggrefe, A. E. Buxton, B. Chaitman, M. Fromer, G. Gregoratos, G. Klein, A. J. Moss, et al. ACC/AHA/ESC 2006 guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: A report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death) Developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society Europace, September 1, 2006; 8(9): 746 - 837. [Full Text] [PDF] |
||||
![]() |
T. Aiba, W. Shimizu, I. Hidaka, K. Uemura, T. Noda, C. Zheng, A. Kamiya, M. Inagaki, M. Sugimachi, and K. Sunagawa Cellular Basis for Trigger and Maintenance of Ventricular Fibrillation in the Brugada Syndrome Model: High-Resolution Optical Mapping Study J. Am. Coll. Cardiol., May 16, 2006; 47(10): 2074 - 2085. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Castro Hevia, C. Antzelevitch, F. Tornes Barzaga, M. Dorantes Sanchez, F. Dorticos Balea, R. Zayas Molina, M. A. Quinones Perez, and Y. Fayad Rodriguez Tpeak-Tend and Tpeak-Tend Dispersion as Risk Factors for Ventricular Tachycardia/Ventricular Fibrillation in Patients With the Brugada Syndrome J. Am. Coll. Cardiol., May 2, 2006; 47(9): 1828 - 1834. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. A. Marill and P. T. Ellinor Case 37-2005 -- A 35-Year-Old Man with Cardiac Arrest while Sleeping N. Engl. J. Med., December 8, 2005; 353(23): 2492 - 2501. [Full Text] [PDF] |
||||
![]() |
P. Brugada, R. Brugada, J. Brugada, S. G. Priori, C. Napolitano, P. Brugada, R. Brugada, J. Brugada, S. G. Priori, and C. Napolitano Should patients with an asymptomatic Brugada electrocardiogram undergo pharmacological and electrophysiological testing? Circulation, July 12, 2005; 112(2): 279 - 292. [Full Text] [PDF] |
||||
![]() |
D. P. Zipes, M. J. Ackerman, N.A. M. Estes III, A. O. Grant, R. J. Myerburg, and G. Van Hare Task Force 7: Arrhythmias J. Am. Coll. Cardiol., April 19, 2005; 45(8): 1354 - 1363. [Full Text] [PDF] |
||||
![]() |
C. Antzelevitch, P. Brugada, M. Borggrefe, J. Brugada, R. Brugada, D. Corrado, I. Gussak, H. LeMarec, K. Nademanee, A. R. Perez Riera, et al. Brugada Syndrome: Report of the Second Consensus Conference: Endorsed by the Heart Rhythm Society and the European Heart Rhythm Association Circulation, February 8, 2005; 111(5): 659 - 670. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Eckardt, V. Probst, J. P.P. Smits, E. S. Bahr, C. Wolpert, R. Schimpf, T. Wichter, P. Boisseau, A. Heinecke, G. Breithardt, et al. Long-Term Prognosis of Individuals With Right Precordial ST-Segment-Elevation Brugada Syndrome Circulation, January 25, 2005; 111(3): 257 - 263. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. J.J. Wellens Cardiac arrhythmias: The quest for a cure: A historical perspective J. Am. Coll. Cardiol., September 15, 2004; 44(6): 1155 - 1163. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. H. Thrall Personalized Medicine Radiology, June 1, 2004; 231(3): 613 - 616. [Full Text] [PDF] |
||||
![]() |
A. Oto Brugada sign: a normal variant or a bad omen? Insights for risk stratification and prognostication Eur. Heart J., May 2, 2004; 25(10): 810 - 811. [Full Text] [PDF] |
||||
![]() |
D. P. Zipes The year in electrophysiology J. Am. Coll. Cardiol., April 7, 2004; 43(7): 1306 - 1314. [Full Text] [PDF] |
||||
![]() |
Brugada Syndrome Predicts Sudden Death Journal Watch Emergency Medicine, March 3, 2004; 2004(303): 3 - 3. [Full Text] |
||||
![]() |
H. J.J. Wellens and A. P. Gorgels The Electrocardiogram 102 Years After Einthoven Circulation, February 10, 2004; 109(5): 562 - 564. [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2003 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |