Brugada-type Electrocardiogram Pattern Research Articles

Interictal cardiac repolarization abnormalities in people with epilepsy

Background and objectiveThe occurrence of cardiac electrical abnormalities such as repolarization disorders in patients with epilepsy was previously documented and may, in part, clarify the mechanism of sudden unexpected death in those patients. The aim of this study was to investigate the frequency of cardiac repolarization disorders among patients with epilepsy and whether specific demographic- or disease-related features were associated with their occurrence. Subjects and methodsThis cross-sectional study was carried out on 1000 subjects with epilepsy who were compared with age- and sex-matched 2500 subjects without epilepsy. Clinical assessment, which included careful history taking and examination, was carried out for all participants in addition to resting 12-lead electrocardiogram (ECG) recording. Electrocardiograms were reviewed by experienced cardiologists. Electrocardiogram intervals were measured, and morphological abnormalities were identified using standard guidelines. ResultsRepolarization abnormalities were found in 142 (14.2%) patients with epilepsy. A statistically significant elevation in percentage of corrected QT interval (QTc) prolongation (both severe and borderline) among patients with epilepsy compared with controls was documented (8.4% vs 2%, P<0.001). Epilepsy increased the likelihood of hosting prolonged QTc more than 4 times (95% confidence interval: 3.175–6.515; odds ratio: 4.548; P<0.001). Affected patients were significantly older (95% confidence interval: 1.012–1.044; odds ratio: 1.027; P=0.001), and the abnormality was significantly more prevalent among those with poor seizure control (95% confidence interval: 1.103–2.966; odds ratio: 1.809; P=0.019). On the other hand, early repolarization (ER) pattern and Brugada type ECG pattern (BP) were significantly more prevalent in subjects without epilepsy. ConclusionsCorrected QT interval prolongation (both severe and borderline) was more prevalent among patients with epilepsy, especially if uncontrolled or elderly. Electrocardiogram should be established as a part of the diagnostic workup of epilepsy in order to identify such electrocardiographic abnormality.

204: Clinical and Genetic Characteristics of Brugada Syndrome in a Tunisian Population

The Brugada syndrome (BS) is a clinical entity involving cardiac sodium channelopathy, typical electrocardiogram (ECG) changes and predisposition to ventricular arrhythmia. This syndrome is mainly recognized by specialized cardiologists and electrophysiologists. Data regarding BS largely come from multicentre registries or Asian countries. The objective of this study was to investigate the clinical characteristics and prognosis of native Tunisian subjects with the Brugada-type ECG pattern (BS) BS has been diagnosed in 10 patients (9 men, 1 woman, mean age 38±11 years) at the department of cardiology Sfax since January 2002. Patients were referred from primary care physicians for ECG abnormalities, syncope or ventricular arrhythmia, or were diagnosed incidentally on an ECG obtained for other purposes. Nine patients had had an episode of syncope, dizziness or chest pain, 1 patient was asymptomatic at diagnosis and any patients survived sudden cardiac death. The electrocardiographics (ECGs) of all patients showed spontaneous ST-segment elevation in leads V1–3 at baseline and 8 patients (80%) showed transient normalization of the ST-segment elevation during follow-up. Two patients had a family history of sudden cardiac death at younger than 45 years of age. No patient has been found to have a mutation in the SCN5A gene. An implantable cardioverter-defibrillator was implanted in four patients (40%), including the patient with a history of syncope. No event occurred in our population after a mean follow-up of 26±29 months. BS is present in the Tunisian population and is probably under-recognized. Long-term prognosis of individuals with BS, especially in sporadic, asymptomatic cases, needs to be clarified.

Prevalence of Brugada-type ECG pattern and early ventricular repolarization pattern in Tunisian athletes.

IntroductionNo data regarding the prevalence of the Brugada-type electrocardiogram (ECG) pattern and the early ventricular repolarization pattern (ERP) in the North African population were available. The aims of this study were to determine the frequency of Brugada-type ECG pattern and ERP in Tunisia and to evaluate ECG descriptors of ventricular repolarization in a population of athletes.MethodsOver a 2-year period, resting 12-lead ECG recordings were analyzed from athletes (n = 540; 348 males; age 18.3 ± 2.4 years). Brugada-type ECG pattern was defined as Type 1, 2, or 3, and ERP was characterized by an elevation of the J point in the inferior and/or lateral leads. The population was divided into three groups of athletes: ERP group; Brugada-type ECG pattern group; and control group, with neither ERP nor Brugada ECG pattern. Clinical and electrocardiographic parameters were compared among the study groups.ResultsNine subjects (1.66%) had a Brugada-type ECG pattern. None of them had the coved-type, 3 (0.6%) had the Type 2, and 6 (1.1%) had the Type 3. All subjects were asymptomatic. A Brugada-type ECG pattern was observed in seven males. No female had the Type 2 Brugada ECG pattern. ECG parameters were similar among Brugada-type ECG pattern and control athletes. ERP (119 subjects, 22%) was obtained in 98 males. Heart rate was lower, the QRS duration shorter and QT and Tpeak–Tend intervals were longer in ERP than control groups.ConclusionThe results indicate that the frequency of the Brugada-type ECG pattern and ERP were respectively 1.66% and 22.00% in athletes, being more prevalent in males. The ERP group experienced shorter QRS duration and longer Tpeak–Tend interval than in the control population.

The prevalence and relevance of the Brugada-type electrocardiogram in the Danish general population: data from the Copenhagen City Heart Study

The prevalence of the Brugada-type electrocardiogram (ECG) in the Danish population is not known. Inhabitants from the city of Copenhagen, Denmark, have participated in a prospective study since 1976. Four cross-sectional surveys have been carried out. Follow-up was performed using public registers. At each examination, the participants had an ECG registered. ECGs, showing right bundle branch block (RBBB) were examined for a possible Brugada-type pattern. A total of 42,560 ECGs had been registered from 18,974 participants. 1,284 had been coded as RBBB. Among these ECGs, we found no ECGs showing type 1 Brugada pattern, and 14 showing type 2 or 3 pattern. The prevalence of the total number of ECGs with Brugada pattern was 7/10,000. None of the subjects with a Brugada-pattern ECG died suddenly during follow-up. The Brugada-type ECG pattern is rare in the general Danish population. None of the subjects with a Brugada-type ECG died suddenly during a follow-up of 6-33 years.

Local conduction block of the atria by premature stimulus in a patient with Brugada syndrome

A 46-year-old man with type II Brugada electrocardiogram pattern changed to a type I Brugada type electrocardiogram pattern by class I antiarrhythmic drug (pilsicainide) underwent electrophysiologic study. Ventricular fibrillation was induced by double extrastimuli from the right ventricular (RV) apex. Monophasic action potentials (MAPs) were then recorded from the high right atrium. Duration of MAP at a coupling interval of 220 milliseconds was 122 milliseconds, and local activation of S2 spread to the left atrium. However, MAP at a coupling interval of 210 milliseconds was 112 milliseconds, and local activation of S2 failed to spread to the rest of atrium.

Prevalence of a Brugada Pattern Electrocardiogram in an Urban Population in the United States

To determine the prevalence of a Brugada-type pattern on routine electrocardiogram (ECG) in an urban population served by a tertiary medical center in the United States. The investigators reviewed the ECG database at the Montefiore Medical Center, a tertiary teaching center in the Bronx, New York, over a 10-year period. During this time, 653,006 ECG records in 162,590 patients were identified. The database was queried by applying standard diagnostic criteria in an attempt to identify records with apparent conduction delay and ST abnormality in leads V1-V3. Additional diagnostic criteria were then applied to identify records in an attempt to mimic Brugada-like changes. A cardiac electrophysiologist reviewed records meeting these criteria to confirm the presence of a Brugada-type pattern. In total, 16,067 patients (9.8%) were identified as having ECGs with right bundle branch block, incomplete right bundle branch block, or RSR' in leads V1 and V2. After applying additional diagnostic criteria evaluating ST segment shift, 456 patients were identified as having a pattern potentially consistent with a Brugada-type ECG. The presence of a Brugada-type pattern was confirmed by physician overread in 20 patients (0.012%). The Brugada-type ECG pattern is infrequently seen in a large ethnically diverse urban US population. Further evaluation should be considered when this pattern is seen on routine ECG.

Prognosis of Subjects With Brugada-Type Electrocardiogram in a Population of Middle-Aged Japanese Diagnosed During a Health Examination

There is controversy about the clinical significance of an incidental finding of a Brugada-type electrocardiogram (ECG) pattern. To assess the prognosis of subjects with a diagnosis of a Brugada-type ECG pattern during a health examination, 13,904 subjects (mean age 58 +/- 10 years) who had the annual health examination including an ECG offered to adult citizens of Moriguchi City, Osaka, Japan, in 1997 were studied. A Brugada-type ECG pattern was found in 98 subjects, and 37 subjects had type 1. During a mean follow-up of 7.8 +/- 1.6 years, there were 4 deaths (4.1%) and 1 cardiovascular death (1.0%) in subjects with a Brugada-type ECG pattern, whereas there were 612 deaths (4.4%) and 142 cardiovascular deaths (1.0%) in those without. One cardiovascular death in a subject with a Brugada-type ECG pattern was sudden death. Unadjusted proportional hazards regression analyses showed that Brugada-type ECG pattern was not associated with either all-cause (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.34 to 2.41) or cardiovascular mortality (HR 0.97, 95% CI 0.14 to 6.93). After adjustment for cardiovascular risk factors, Brugada-type ECG pattern had no association with either all-cause (HR 0.77, 95% CI 0.29 to 2.07) or cardiovascular mortality (HR 1.01, 95% CI 0.14 to 7.31). In conclusion, Brugada-type ECG patterns diagnosed during a health examination in a middle-aged population had a low risk of sudden death and were not associated with increased risk of either cardiovascular or all-cause mortality.

Neurally Mediated Susceptibility in Individuals with Brugada‐Type ECG Pattern

Neurally mediated syncope and Brugada syndrome (BS) share common pathophysiologic mechanisms related to autonomic nervous system modulations, and particularly with increased vagal tone. This study aimed to investigate the incidence of neurally mediated susceptibility in individuals with Brugada-type electrocardiogram (ECG) pattern. Eight asymptomatic male individuals (mean age 41.6 +/- 10.6 years) with spontaneous or procainamide-induced type 1 ECG pattern of BS and structurally normal hearts underwent a drug-free head-up tilt test. Twenty-five healthy male subjects (mean age 37.4 +/- 14.1 years) with normal ECG and without structural heart disease were included in the study, and served as comparative controls. A positive tilt test response was observed in three out of eight subjects with the Brugada-type ECG pattern (37%) and in three out of 25 controls (12%) (P = 0.018). This study demonstrates a high incidence of neurally mediated susceptibility in asymptomatic individuals with Brugada-type ECG pattern. Severe diagnostic and therapeutic dilemmas may rise from this coexistence. A positive tilt test in subjects with Brugada-type ECG displaying a history of syncope may mislead the physician to a false sense of security. Further studies are required to validate our findings and possibly evaluate the role of tilt test in risk stratification of patients with BS.

Frequency of Brugada-Type ECG Pattern (Brugada Sign) in Southern Turkey

The frequency of Brugada sign was found to differ among ethnic groups. Yet, there is no data regarding the prevalence of Brugada syndrome and sign in our country. The aim of this study was to determine the frequency of a Brugada-type electrocardiogram (ECG) pattern in southern Turkey. A total of 1,238 subjects (males, 671, females, 567) were included in the study. The previously archived ECGs of 807 subjects without any evidence of structural heart disease were chosen randomly and evaluated. In addition, prospective analysis of the ECGs of 431 subjects (males, 293, females, 138) randomly chosen from healthy university students were also included. The mean age was 38.9 +/- 17.6 years. Six subjects (0.48%) had a Brugada-type ECG pattern. One (0.08%) of them had the coved-type and 5 (0.40%) had the saddleback-type. All subjects were asymptomatic. A Brugada-type ECG pattern was obtained in 1 (0.17%) female and in 5 (0.74%) males (OR: 4.2 CI: 0.5-36.4, P = 0.2). The Brugada-type ECG pattern frequency was 0.12% in subjects >or= 25 years old and 1.16% in subjects between 17-24 years old (OR: 9.4 CI: 1.1-81.2, P = 0.02). Young males between 17-24 years had the highest (1.70%) frequency. The results indicate that the frequency of the Brugada-type ECG pattern was 0.48% in the general population, being more prevalent in young males in our region. These results are similar to the findings of studies performed in other countries.

Unmasking of Brugada Syndrome by an Antiarrhythmic Drug in a Patient with Septic Shock

Asymptomatic Brugada syndrome patients often display concealed Brugada-type electrocardiogram patterns that result in under-diagnosis of this syndrome. These patients include individuals of both genders and a wide range of ages. They are as likely as non-Brugada patients to have normal longevity or to suffer from a critical illness. Here we report a case of septic shock in which Brugada-type electrocardiogram patterns were induced by pilsicainide administration for the treatment of atrial fibrillation. This case report suggests that some drugs used in the treatment of septic shock can unmask the Brugada-type electrocardiogram pattern and induce lethal ventricular tachyarrhythmia.

Prevalence and prognosis of subjects with brugada-type ECG pattern in a young and middle-aged finnish population

Patients with the manifest Brugada syndrome have an inordinate risk of sudden death and are candidates for implantation of a defibrillator. The Brugada type electrocardiogram (ECG) abnormality (the “Brugada sign”), however, is known to be associated with a wide range of conditions, many of which may not pose such a threat. Clinicians need guidance in choosing a rational approach for the evaluation and treatment of patients with a finding of the Brugada sign.A systematic literature search was performed to identify publications on the Brugada syndrome and the Brugada-type ECG abnormality, with special emphasis on analyzing outcomes data. In addition, the ECG database of our institution was reviewed for tracings consistent with the Brugada sign, and, when possible, clinical correlations were made.Patients with the Brugada sign and a family history of sudden death or a personal history of syncope are at a high risk of sudden death and therefore should be strongly considered for implantation of a defibrillator. In patients who are hospitalized and critically ill, the Brugada sign is frequently the result of severe hyperkalemia, drug toxicity, or right ventricular injury. In most individuals with no symptoms and without a family history of sudden death, the Brugada sign is likely a normal variant.Most patients with the Brugada sign can be risk-stratified with simple clinical tools. Specific testing for the Brugada syndrome should be reserved for questionable cases and for the research setting. A provisional diagnostic-therapeutic algorithm is offered as a means of assisting the clinician in the evaluation and treatment of patients with the Brugada sign.