Typical ECG Changes Unmasked by Ajmaline in a Patient with Brugada Syndrome and Left Bundle Branch Block

Brugada syndrome is a channelopathy associated with right bundle branch block and ST segment elevation in the right precordial leads. These electrocardiographic signs may not be apparent most of the time but can be unmasked by certain antiarrhythmic agents. Until now, all of the reports on this syndrome have focused on patients with no significant intraventricular conduction delay at baseline electrograms. In this report, we describe a patient with Brugada syndrome with left bundle branch block at baseline ECG. After intravenous ajmaline, the patient developed right bundle branch block and ST segment elevations in the right precordial leads.     

Brugada syndrome,Brugada phenocopy or none?

Brugada syndrome is a form of inherited arrhythmia syndrome characterized by a distinct ST‐segment elevation in the right precordial leads. Brugada phenocopies are clinical entities that present with an electrocardiographic pattern identical to Brugada syndrome and may obey to various clinical conditions. We present a case of a suicidal attempt using a high dose of propafenone causing a Brugada‐type electrocardiographic pattern. Is this a Brugada syndrome case, a Brugada phenocopy or something else?     

Paradoxical effect of ajmaline in a patient with Brugada syndrome.

AIMS: The typical Brugada ECG pattern consists of a prominent J-wave associated with ST-segment elevation localized in the right precordial leads V1-V3. In many patients, the ECG presents periods of transient normalization and the Brugada-phenotype can be unmasked by the administration of class-I antiarrhythmics. Reports have documented the heterogeneity of the Brugada syndrome ECG-phenotype characterized by unusual localization of the ECG abnormalities in the inferior leads. Case report A 51-year-old man, without detectable structural heart disease, was referred to us because of a history of syncope, dizziness, and palpitations. The ECG showed a J-wave and ST-segment elevation in the right precordial leads, suggesting Brugada syndrome. As other causes of the ECG abnormalities were excluded, the patient underwent an electrophysiological study that documented easy induction of ventricular fibrillation. During infusion of ajmaline, new prominent J-waves and ST-segment elevation appeared in the inferior leads, whereas the basal ECG abnormalities in the right precordial leads normalized. After infusion of isoprenaline, the ECG-pattern resumed the typical Brugada pattern. An implantable cardioverter-defibrillator was recommended. CONCLUSION: In our patient, the double localization of the typical Brugada-pattern and the paradoxical effect of ajmaline on the ECG abnormalities confirmed the possibility of a phenotype heterogeneity in the Brugada syndrome.     

Body surface potential mapping in patients with Brugada syndrome: right precordial ST segment variations and reverse changes in left precordial leads

OBJECTIVE: The aim of this study was to perform quantitative signal analysis of high-resolution body surface potential mapping (BSPM) recordings to assess its usefulness for the electrocardiographic characterization of patients with Brugada syndrome. The diagnostic value of the QRS integral and of the gradient of the ST segment have not been elucidated in Brugada syndrome. METHODS: In 27 subjects (16 with Brugada syndrome and 11 healthy subjects), 120-lead BSPMs were recorded at baseline and after pharmacological provocation with intravenous administration of ajmaline (1 mg/kg). The recordings were analyzed for two regions outside the positions of the standard ECG leads: the right precordial leads (RPL) on the second and third intercostal space (high RPL) and the left precordial leads (LPL) between the fifth and seventh intercostal space (low LPL). RESULTS: At baseline, in high RPL regions, patients with Brugada syndrome showed more positive QRS integrals (-5+/-8 vs. -16+/-8 mV ms) and a steeper negative ST segment gradient (-0.62+/-0.41 vs. -0.29+/-0.40 mV/s) compared to healthy subjects, P<0.001. In contrast, in low LPL regions, reduced QRS integrals and positive ST segment gradients were observed. These ECG signs were even more pronounced after intravenous ajmaline and showed a better discrimination for patients with Brugada syndrome than differences in RPL or LPL during baseline, respectively. CONCLUSIONS: In the left precordial leads, patients with Brugada syndrome showed ECG changes which were reversed in relation to the ECG changes observed in right precordial leads. BSPM measurement is a useful tool to improve the understanding of the electrocardiographic changes in the Brugada syndrome.     

Rhabdomyoma of the interventricular septum presenting as a Brugada phenocopy

Brugada syndrome is a channelopathy characterised electrocardiographically by distinctive coved ST-segment elevation in the right precordial leads and is associated with a predisposition for sudden death secondary to ventricular arrhythmias in otherwise healthy patients. Previously known as Brugada-like patterns, Brugada phenocopies include agents and conditions that mimic true Brugada syndrome, presenting with an acquired Brugada Type-1 ECG pattern. We describe the first reported case of a 17-month-old female with an asymptomatic rhabdomyoma of the interventricular septum that presented as a Brugada phenocopy.     

Syncope in male--let us think about Brugada syndrome! Presentation of 3 cases

Brugada syndrome is a genetic disease characterised by ST segment elevation in right precordial leads and the occurrence of episodes of polymorphic ventricular tachycardia. It is also associated with a high risk of sudden death. We describe three males in whom Brugada syndrome was finally diagnosed after several hospitalisations due to syncope and ventricular tachycardia.     

Right ventricular cardiomyopathy showing right bundle branch block and right precordial ST segment elevation

A 73-year-old man who had a family history of sudden death, experienced syncope. His electrocardiogram (ECG) presented right bundle branch block and right precordial ST segment elevation which are findings identical with those in Brugada syndrome. The cardiac MRI showed right ventricular mild dilatation, and endomyocardial biopsy revealed fatty replacement of myocardial fibers. Though no ventricular tachyarrhythmias were induced during an electrophysiologic test, the effects on ECG of antiarrhythmic agents and autonomic modulations were similar to those in Brugada syndrome. This case may suggest the relationship between Brugada syndrome and right ventricular cardiomyopathy.     

T Wave Alternans Does not Assess Arrhythmic Risk in Patients with Brugada Syndrome

Background: Brugada syndrome is associated with a risk for sudden death, but the arrhythmic risk in an individual Brugada syndrome patient is difficult to predict. Pathologic changes in the early repolarization phase of the ventricular action potential probably constitute part of the arrhythmogenic substrate in Brugada syndrome. Microvolt T wave alternans (TWA) assesses dynamic beat‐to‐beat changes in repolarization and has been suggested as a marker for repolarization‐related sudden death. We therefore tested whether TWA is an indicator for arrhythmias in Brugada syndrome with a focus on right precordial ECG leads. Methods: We assessed TWA in nine symptomatic, inducible patients with established Brugada syndrome and in seven healthy controls. TWA was assessed at rest and during exercise using both standard methods and an algorithm that assesses TWA in the early ST segment and the right precordial leads. Results : None of the Brugada patients developed TWA in this study irrespective of analysis at rest or during exercise, neither using standard methods nor when the early ST segment was included in the analysis. When the early ST segment was included in the analysis, nonsustained TWA was found in three out of seven, and sustained TWA in one control. Conclusion: T wave alternans is not an appropriate test to detect arrhythmic risk in patients with Brugada syndrome.     

Spontaneous onset of ventricular fibrillation in Brugada syndrome with J wave and ST-segment elevation in the inferior leads.

We report the case of a 52-year-old man with variant Brugada syndrome who was successfully resuscitated from ventricular fibrillation (VF). Resting ECG showed J wave and ST-segment elevation in the inferior leads but no coved or saddleback ST-segment elevation in the right precordial leads. Pilsicainide infusion provoked coved-type ST-segment elevation in the right precordial leads and mild ST-segment elevation 80 ms after the J point in the inferior leads. During an emergency, 12-lead ECG showed that spontaneous onset of VF was preceded by left bundle branch block and superior axis-type ventricular extrasystoles. The present case provides additional information on the site of origin of VF in patients with Brugada syndrome.     

Current electrocardiographic criteria for diagnosis of Brugada pattern: a consensus report

Brugada syndrome is an inherited heart disease without structural abnormalities that is thought to arise as a result of accelerated inactivation of Na channels and predominance of transient outward K current (I(to)) to generate a voltage gradient in the right ventricular layers. This gradient triggers ventricular tachycardia/ventricular fibrillation possibly through a phase 2 reentrant mechanism. The Brugada electrocardiographic (ECG) pattern, which can be dynamic and is sometimes concealed, being only recorded in upper precordial leads, is the hallmark of Brugada syndrome. Because of limitations of previous consensus documents describing the Brugada ECG pattern, especially in relation to the differences between types 2 and 3, a new consensus report to establish a set of new ECG criteria with higher accuracy has been considered necessary. In the new ECG criteria, only 2 ECG patterns are considered: pattern 1 identical to classic type 1 of other consensus (coved pattern) and pattern 2 that joins patterns 2 and 3 of previous consensus (saddle-back pattern). This consensus document describes the most important characteristics of 2 patterns and also the key points of differential diagnosis with different conditions that lead to Brugada-like pattern in the right precordial leads, especially right bundle-branch block, athletes, pectus excavatum, and arrhythmogenic right ventricular dysplasia/cardiomyopathy. Also discussed is the concept of Brugada phenocopies that are ECG patterns characteristic of Brugada pattern that may appear and disappear in relation with multiple causes but are not related with Brugada syndrome.     

QT-interval prolongation in right precordial leads: an additional electrocardiographic hallmark of Brugada syndrome

OBJECTIVES: The aim of this study was to evaluate whether the occurrence of the Brugada Syndrome typical electrocardiogram (ECG) pattern (i.e., right bundle branch block, coved-type ST-segment elevation, and T-wave inversion in the right precordial leads) is characterized by a concomitant lengthening of QT intervals in the right precordial leads. BACKGROUND: It has been suggested that the typical ECG pattern of Brugada syndrome is due to a decreased net inward current during phase 1 of the action potential, which also leads to its prolongation in the right epicardium. METHODS: Thirty-two subjects (19 males) age 37 +/- 15 years with a suspicious baseline ECG, or who were relatives of Brugada syndrome patients, underwent 12-lead ECG before and after the administration of flecainide. RESULTS: The flecainide test was negative in 14 and positive in 18 subjects. After flecainide administration, the positive ECGs were characterized by a greater QT interval corrected for heart rate (QTc) prolongation in the right precordial leads than that in the negative ECGs (78.2 +/- 35.5 ms vs. 22.0 +/- 28.4 ms in V(1) and 107.1 +/- 43.8 ms vs. 26.7 +/- 30.1 ms in V(2); p < 0.01), whereas there was no difference in the QTc prolongation in the left precordial leads (55.2 +/- 25.3 ms vs. 35.1 +/- 28.1 ms in V(5) and 53.1 +/- 32.8 ms vs. 27.3 +/- 22.4 ms in V(6); p = NS). CONCLUSIONS: In accordance with the electrophysiological background, the typical ECG pattern of Brugada syndrome is also characterized by a considerable prolongation of the QT interval in right precordial leads.     

Brugada Phenocopy: New Terminology and Proposed Classification

Brugada syndrome is a channelopathy characterized on ECG by coved ST‐segment elevation (≥2 mm) in the right precordial leads and is associated with an increased risk of malignant ventricular arrhythmias. The term Brugada phenocopy is proposed to describe conditions that induce Brugada‐like ECG manifestations in patients without true Brugada syndrome. An extensive review of the literature identified case reports that were classified according to their suspected etiological mechanism. Future directions to learn more about these intriguing cases is discussed.     

Brugada-like electrocardiographic pattern unmasked by fever

Brugada syndrome is characterized by right bundle branch block morphology and ST-segment elevation in the right precordial leads and a propensity to develop ventricular arrhythmias. Mutations in a cardiac sodium channel gene have been linked to this syndrome, and the ionic mechanisms responsible for the electrocardiographic phenotype are temperature-dependent. This case report describes a patient in whom a typical Brugada ECG pattern developed during fever and could be reproduced at normal body temperature by administration of pilsicainide.     

Presence of intermittent J waves in multiple leads in relation to episode of atrial and ventricular fibrillation

Brugada syndrome is characterized by J wave and ST-segment elevation of right precordial leads and causes idiopathic ventricular fibrillation. We experienced a patient of Brugada syndrome with prominent J wave and ST-segment elevation not only in V(1) to V(3) but also in many leads. He suffered spontaneous ventricular fibrillation and resuscitated by direct current. He has no structural heart disease.     

Spontaneous right ventricular outflow tract tachycardia in a patient with Brugada syndrome

We report the case of a 28-year-old man with no structural heart disease, who exhibited clearly augmented ST segment elevation in the right precordial leads, followed by induction of spontaneous right ventricular outflow tract tachycardia with intravenous administration of Class IA antiarrhythmic drugs. The electrophysiologic mechanism of this tachycardia was thought to be triggered activity due to delayed afterdepolarizations. Due to the existence of substrates that were similar to Brugada syndrome combined with right ventricular outflow tract tachycardia, this case may represent a subtype of Brugada syndrome.     

An Unusual Case of Brugada Syndrome in a 10-year-old Child with Fevers

Brugada syndrome is an arrhythmogenic disease characterized by a pattern of ST segment elevation in the right precordial leads on an electrocardiogram with an increased risk of sudden cardiac death. It is primarily reported in adults with limited data about the prevalence, prognosis, and long-term management in children. We describe a 10-year-old boy with a family history of sudden cardiac death, who had near syncope associated with a febrile illness. A screening electrocardiogram revealed ST segment elevation in the right precordial leads consistent with Type-1 Brugada syndrome. An electrocardiogram after recovery from his illness showed Type-2 “saddle-back” ST segment changes. An echocardiogram and a cardiac magnetic resonance imaging revealed a normal heart without myocardial fibrofatty infiltration, scar, or ischemia. A tilt-table test was negative. Implantable cardioverter-defibrillator placement remains the only effective treatment for patients with symptomatic Brugada syndrome; however, risk stratification of asymptomatic patients continues to remain a challenge. Although some investigators have reported the use of electrophysiological studies for distinguishing between high and low risk patients with Brugada syndrome, there are no precise predictors of risk for sudden cardiac death in pediatric patients. After careful discussion, this patient was considered intermediate to high risk for sudden cardiac death and had successful implantation of a transvenous defibrillator. Although Brugada syndrome is a rare diagnosis in the pediatric population, such patients should be referred for further evaluation and management.     

Does early repolarization in the athlete have analogies with the Brugada syndrome?

AIMS: To re-examine the prevalence and presentation of early repolarization in athletes and to compare it with electrocardiographic abnormalities observed in patients with the Brugada syndrome. METHODS: Electrocardiograms of 155 male athletes and 50 sedentary controls were studied. Early repolarization was considered present if at least two adjacent precordial leads showed elevation of the ST segment > or =1 mm. Amplitude and morphology of ST elevation, the leads where it was present and the lead in which it showed its maximum value were analysed together with QRS duration, the presence of right ventricular activation delay, QT and QTc duration. Data were compared with those obtained by electrocardiograms of 23 patients with the Brugada syndrome. RESULTS: Early repolarization was found in 139 athletes (89%) and 18 controls (36%, P< or =0.025), being limited to right precordial leads in 42 (30%) athletes and 13 (72%) controls (P< or =0.001). Only 12 (8.6%) athletes and one control (5.5%) with early repolarization had an ST elevation 'convex toward the top' in right precordial leads, similar to that seen in the Brugada syndrome. In athletes the maximum ST elevation was greater (2.3+/-0.6 mm) than in the controls (1.2+/-0.8 mm; P< or =0.004) but significantly lower than in patients with the Brugada syndrome (4.4+/-0.7 mm; P< or =0.0001). Patients with the Brugada syndrome also had a greater QRS duration (0.11+/-0.02 s) than athletes (0.090+/-0.011 s; P< or =0.0001) with early repolarization. CONCLUSIONS: Early repolarization is almost always the rule in athletes but it is also frequent in sedentary males. Tracings somewhat simulating the Brugada syndrome were observed in only 8% of athletes without a history of syncope or familial sudden death. Significant differences exist between athletes with early repolarization and patients with the Brugada syndrome as regards the amplitude of ST elevation and QRS duration.     

Síncope em contexto febril – caso clínico de síndrome de Brugada

In 1992, Brugada and Brugada first described a new entity, which became known as Brugada syndrome, that is associated with a high risk of ventricular arrhythmias and sudden cardiac death in patients without structural heart disease. This syndrome is characterized by a distinct electrocardiographic phenotype, type 1 Brugada pattern, consisting of a coved ST‐segment elevation (≥0.2 mV) followed by a negative T wave in more than one right precordial lead. This pattern is dynamic, and can be spontaneous or concealed, but is unmasked under certain circumstances, like febrile states.The authors report a case in which the diagnosis of Brugada syndrome was made in the course of etiologic investigation of recurrent syncope in a febrile state.     

Electrocardiographic findings typical of Brugada syndrome unmasked by cocaine consumption

Brugada syndrome is characterized by the presence of right bundle branch block on electrocardiography and by ST-segment elevation in the right precordial leads (V1-V3), by the absence of structural cardiac abnormalities, and by episodes of syncope or sudden death. On occasion, diagnosis is made difficult by temporary normalization of the ECG. The condition can be unmasked by potent sodium channel blockers, such as flecainide. Our patient presented with a Brugada syndrome-type ECG after intake of a large amount of cocaine.