288
Letters to the Editor
Terminological clarification of Brugada Phenocopy, Brugada Syndrome, and the Brugada ECG pattern Re. Early repolarization pattern in patients with provocable Brugada Phenocopy: A marker of additional arrhythmogenic cardiomyopathy Daniel D. Anselm, Adrian Baranchuk ⁎ Division of Cardiology, Kingston General Hospital, Queen's University, Kingston, Ontario, Canada
a r t i c l e
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Article history: Received 22 August 2013 Accepted 25 November 2013 Available online 4 December 2013 Keywords: Brugada Phenocopy Brugada Syndrome Early repolarization Arrhythmogenic right ventricular cardiomyopathy
We read the recent paper by Dr. Peters [1] with great interest and noted that the term Brugada Phenocopy (BrP) was used in the title; however, the discussion focuses on early repolarization pattern (ERP) in the context of arrhythmogenic right ventricular cardiomyopathy and provocable Brugada ECG pattern with sodium channel blockers. We have been publishing extensively on the subject of BrP [2–9] and would like to suggest a clarification on terminology so as to facilitate future research on BrP and avoid confusion with other forms of ERP. As previously described, Bayés de Luna et al. articulated the ECG criteria for type 1 and type 2 Brugada ECG patterns in the most recent consensus report [10]. In our recent publications [2–9], we have established the diagnostic criteria for BrP and would like to identify salient features that differentiate BrP from true congenital Brugada Syndrome (BrS). First, patients with BrP and BrS both have identical type 1 or type 2 ECG patterns in precordial leads V1–V3. Second, patients with BrP have an identifiable underlying condition that elicits the Brugada ECG pattern and once this underlying condition resolves, the ECG normalizes. Additionally, patients with BrS have a high clinical pretest probability of true congenital BrS, while patients with BrP have a low clinical pretest probability of true congenital BrS suggested by lack of symptoms, medical history, or family history. Most importantly,
⁎ Corresponding author at: Cardiac Electrophysiology and Pacing, Kingston General Hospital, Queen's University, K7L 2V7, Canada. Tel.: +1 613 549 6666x3801; fax: + 1 613 548 1387. E-mail address: [email protected] (A. Baranchuk).
0167-5273/$ – see front matter © 2013 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijcard.2013.11.080
patients with BrP have a negative provocative challenge with sodium channel blockers such as procainamide, flecainide, or ajmaline while patients with true congenital BrS have a positive provocative challenge. As such, right ventricular outflow tract sodium channel dysfunction in patients with BrS may have a different pathophysiological basis compared to patients with BrP; however, the underlying mechanisms have yet to be elucidated. We thank Dr. Peters for incorporating the relatively new term Brugada Phenocopy into his literature but we would like to emphasize that this term should not be used for cases where the Brugada ECG pattern is provoked by the use of sodium channel blockers [2]. We are developing an international online registry at www.brugadaphenocopy.com and encourage all investigators working on BrP to submit their cases online in order to provide long-term follow-up and insight into the clinical evolution of this emerging phenomenon. The authors of this manuscript certify that they comply with the Principles of Ethical Publishing in the International Journal of Cardiology. References [1] Peters S. Early repolarization pattern in patients with provocable Brugada Phenocopy: a marker of additional arrhythmogenic cardiomyopathy? Int J Cardiol 2013;168(5):4928–9. [2] Baranchuk A, Nguyen T, Ryu MH, et al. Brugada Phenocopy: new terminology and proposed classification. Ann Noninvasive Electrocardiol 2012;17:299–314. [3] Wang JG, McIntyre WF, Kong W, Baranchuk A. Electrocution-induced Brugada Phenocopy. Int J Cardiol 2012;160:e35–7. [4] Anselm DD, Baranchuk A. Brugada Phenocopy in the context of pulmonary embolism. Int J Cardiol 2013;168(1):560. [5] Anselm DD, Baranchuk A. Brugada Phenocopy: redefinition and updated classification. Am J Cardiol 2013;111:453. [6] Anselm DD, Baranchuk A. Brugada Phenocopy emerging as a new concept. Rev Esp Cardiol 2013;66:755. [7] Anselm DD, Rodriguez Genaro N, Baranchuk A. Possible Brugada Phenocopy induced by hypokalemia in a patient with congenital hypokalemic periodic paralysis. Arq Bras Cardiol 2013 [in press]. [8] Awad SFM, Barbosa-Barros R, de Sousa Belem L, et al. Brugada Phenocopy in a patient with pectus excavatum: systematic review of the ECG manifestations associated with pectus excavatum. Ann Noninvasive Electrocardiol 2013;18(5):415–20. [9] Anselm DD, Barbosa-Barros R, de Sousa Belém L, Nogueira de Macedo R, PérezRiera AR, Baranchuk A. Brugada Phenocopy induced by acute inferior ST-segment elevation myocardial infarction with right ventricular involvement. Inn Card Rhythm Manag 2013;4:1092–4. [10] Bayés de Luna A, Brugada J, Baranchuk A, et al. Current electrocardiographic criteria for diagnosis of Brugada pattern: a consensus report. J Electrocardiol 2012;45:433–42.
Letters to the Editor
Terminological clarification of Brugada Phenocopy, Brugada Syndrome, and the Brugada ECG pattern Re. Early repolarization pattern in patients with provocable Brugada Phenocopy: A marker of additional arrhythmogenic cardiomyopathy Daniel D. Anselm, Adrian Baranchuk ⁎ Division of Cardiology, Kingston General Hospital, Queen's University, Kingston, Ontario, Canada
a r t i c l e
i n f o
Article history: Received 22 August 2013 Accepted 25 November 2013 Available online 4 December 2013 Keywords: Brugada Phenocopy Brugada Syndrome Early repolarization Arrhythmogenic right ventricular cardiomyopathy
We read the recent paper by Dr. Peters [1] with great interest and noted that the term Brugada Phenocopy (BrP) was used in the title; however, the discussion focuses on early repolarization pattern (ERP) in the context of arrhythmogenic right ventricular cardiomyopathy and provocable Brugada ECG pattern with sodium channel blockers. We have been publishing extensively on the subject of BrP [2–9] and would like to suggest a clarification on terminology so as to facilitate future research on BrP and avoid confusion with other forms of ERP. As previously described, Bayés de Luna et al. articulated the ECG criteria for type 1 and type 2 Brugada ECG patterns in the most recent consensus report [10]. In our recent publications [2–9], we have established the diagnostic criteria for BrP and would like to identify salient features that differentiate BrP from true congenital Brugada Syndrome (BrS). First, patients with BrP and BrS both have identical type 1 or type 2 ECG patterns in precordial leads V1–V3. Second, patients with BrP have an identifiable underlying condition that elicits the Brugada ECG pattern and once this underlying condition resolves, the ECG normalizes. Additionally, patients with BrS have a high clinical pretest probability of true congenital BrS, while patients with BrP have a low clinical pretest probability of true congenital BrS suggested by lack of symptoms, medical history, or family history. Most importantly,
⁎ Corresponding author at: Cardiac Electrophysiology and Pacing, Kingston General Hospital, Queen's University, K7L 2V7, Canada. Tel.: +1 613 549 6666x3801; fax: + 1 613 548 1387. E-mail address: [email protected] (A. Baranchuk).
0167-5273/$ – see front matter © 2013 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijcard.2013.11.080
patients with BrP have a negative provocative challenge with sodium channel blockers such as procainamide, flecainide, or ajmaline while patients with true congenital BrS have a positive provocative challenge. As such, right ventricular outflow tract sodium channel dysfunction in patients with BrS may have a different pathophysiological basis compared to patients with BrP; however, the underlying mechanisms have yet to be elucidated. We thank Dr. Peters for incorporating the relatively new term Brugada Phenocopy into his literature but we would like to emphasize that this term should not be used for cases where the Brugada ECG pattern is provoked by the use of sodium channel blockers [2]. We are developing an international online registry at www.brugadaphenocopy.com and encourage all investigators working on BrP to submit their cases online in order to provide long-term follow-up and insight into the clinical evolution of this emerging phenomenon. The authors of this manuscript certify that they comply with the Principles of Ethical Publishing in the International Journal of Cardiology. References [1] Peters S. Early repolarization pattern in patients with provocable Brugada Phenocopy: a marker of additional arrhythmogenic cardiomyopathy? Int J Cardiol 2013;168(5):4928–9. [2] Baranchuk A, Nguyen T, Ryu MH, et al. Brugada Phenocopy: new terminology and proposed classification. Ann Noninvasive Electrocardiol 2012;17:299–314. [3] Wang JG, McIntyre WF, Kong W, Baranchuk A. Electrocution-induced Brugada Phenocopy. Int J Cardiol 2012;160:e35–7. [4] Anselm DD, Baranchuk A. Brugada Phenocopy in the context of pulmonary embolism. Int J Cardiol 2013;168(1):560. [5] Anselm DD, Baranchuk A. Brugada Phenocopy: redefinition and updated classification. Am J Cardiol 2013;111:453. [6] Anselm DD, Baranchuk A. Brugada Phenocopy emerging as a new concept. Rev Esp Cardiol 2013;66:755. [7] Anselm DD, Rodriguez Genaro N, Baranchuk A. Possible Brugada Phenocopy induced by hypokalemia in a patient with congenital hypokalemic periodic paralysis. Arq Bras Cardiol 2013 [in press]. [8] Awad SFM, Barbosa-Barros R, de Sousa Belem L, et al. Brugada Phenocopy in a patient with pectus excavatum: systematic review of the ECG manifestations associated with pectus excavatum. Ann Noninvasive Electrocardiol 2013;18(5):415–20. [9] Anselm DD, Barbosa-Barros R, de Sousa Belém L, Nogueira de Macedo R, PérezRiera AR, Baranchuk A. Brugada Phenocopy induced by acute inferior ST-segment elevation myocardial infarction with right ventricular involvement. Inn Card Rhythm Manag 2013;4:1092–4. [10] Bayés de Luna A, Brugada J, Baranchuk A, et al. Current electrocardiographic criteria for diagnosis of Brugada pattern: a consensus report. J Electrocardiol 2012;45:433–42.
