BACKGROUND: There remains controversy about whether Brugada syndrome (BS) has structural heart changes. We occasionally noted that a patient with BS had a quite unusual regional wall motion abnormality at the basal segment of the interventricular septum (IVS) during echocardiographic examination. The unexpected finding promoted us to reexamine our patients with BS by echocardiographic interrogation in the present study. METHODS: Patients with BS (n = 11), patients with complete right bundle branch block (RBBB) (n = 11), and control subjects (n = 11) were enrolled in this study. Two-dimensional echocardiography (2DE) was performed to obtain parasternal left ventricular long axis view on which M-mode scanning line was adjusted to be perpendicular to the basal segment of IVS for delineation of the segmental motion curve, with a simultaneously electrocardiographic tracing. RESULTS: 2DE revealed a rapid swing motion shifting toward the right ventricle of the IVS basal segment at early systole in 73% (8/11) patients with BS, which was further confirmed on the M-mode curve evidenced by an early systolic notch toward the right ventricle. The position of the notch corresponded to C-point on the mitral motion curve, lasting for (53 +/- 5) ms. There were no similar changes both in patients with RBBB and in the control subjects. CONCLUSION: IVS basal motion abnormalities at early-systolic phase may be the novel finding of BS. (+info)
Significance of cardiac autonomic neuropathy in risk stratification of Brugada syndrome.
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AIMS: Risk stratification in Brugada syndrome (BS) is controversial especially in asymptomatic individuals. The aim of this study was to evaluate the significance of cardiac autonomic neuropathy (CAN) in BS. METHODS AND RESULTS: Patients diagnosed with Brugada ECG pattern were enrolled in the study. Four standard cardiac autonomic function tests were performed. The presence of >or=2 abnormal test results were considered definite evidence for the presence of CAN. Types 1, 2, and 3 Brugada ECG pattern were found in 28, 56, and 31 patients, respectively. CAN was detected in 13 (46%) patients with type 1 Brugada ECG pattern. In contrast, none of the type 2 or 3 Brugada patients had CAN. Of 13 patients with CAN, 11 had previous history of cardiac events (84%), whereas only 2 of 15 patients without CAN had history of previous cardiac events (13%; P = 0.01). The most noteworthy finding was that all of the type 1 Brugada patients with CAN were male (CAN was not detected in females). CONCLUSIONS: It was concluded that CAN is an important risk indicator in BS. CAN is more common in men. Male gender, per se, is not an independent risk factor for development of ventricular arrhythmia but also CAN, which is an important risk factor in BS, is more common in men; therefore men are susceptible to the development of cardiac events. (+info)
ST segment elevation on electrocardiogram: the electrocardiographic pattern of Brugada syndrome.
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A 77-year-old white diabetic woman was brought to our emergency department (ED) after becoming lightheaded and hypotensive at home. Her routine tests including a chest radiograph were normal. Her electrocardiogram (ECG) showed significant ST segment elevation in leads V1 to V4. Serial cardiac enzymes and troponin were within normal limits. Her ECG met the criteria for type 1 Brugada syndrome. Brugada syndrome, which is more common in young Asian males, is an arrhythmogenic disease caused in part by mutations in the cardiac sodium channel gene SCN5A. To diagnose the Brugada syndrome, 1 ECG criterion and 1 clinical criterion should exist. Brugada syndrome can be associated with ventricular tachycardia or fibrillation; the only treatment proven to prevent sudden death is placement of an implantable cardioverter defibrillator, which is recommended in symptomatic patients or in those with ventricular tachycardia induced during electrophysiologic studies and a type 1 ECG pattern of Brugada syndrome. It is important to recognize the Brugada ECG pattern and to differentiate it from other etiologies of ST segment elevation on ECG. (+info)
The occurrence of Brugada syndrome and isolated cardiac conductive disease in the same family could be due to a single SCN5A mutation or to the accidental association of both diseases.
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AIMS: The distinct cardiac arrhythmia diseases, Brugada syndrome (BS) and isolated cardiac conduction disease (ICCD) are caused by heterozygous mutations in the SCN5A gene. Previous studies have demonstrated an intriguing association between ICCD and BS with the same mutation in the SCN5A gene. METHODS AND RESULTS: The proband of a multigenerational family presented BS and a familial history of sudden death. We performed clinical evaluations in family members including drug testing and screening for SCN5A mutations. Based on electrocardiogram features, we identified four individuals with BS, two with ICCD and one compatible with both. For five individuals, one with BS and ICCD, three with BS and one with ICCD, we characterized a heterozygous C- to T- mutation at position 4313 (P1438L) in the SCN5A gene. Expression studies of the P1438L mutation showed non-functional channels. The proband's father with the BS phenotype was not a carrier of the new SCN5A mutation. CONCLUSION: We report the case of a family with BS and/or ICCD and describe a novel mutation, the P1438L SCN5A mutation. In this family, the occurrence of BS and ICCD could be due to this single mutation but also to the accidental association of both diseases. (+info)
Magnetic dispersion of the late repolarization in Brugada syndrome.
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BACKGROUND: Magnetocardiography (MCG) is a new noninvasive modality for recording cardiac depolarization and repolarization and was used in the present study to evaluate abnormalities in patients with Brugada syndrome (BS). METHODS AND RESULTS: The MCG findings of 10 BS, 21 right bundle branch block (RBBB), and 34 normal patients were compared. On the horizontal spatiotemporal activation graph (STAG), the r' waves were more frequently located on the right side in the RBBB than in the normal (p=0.001) or BS groups (p=0.001). The maximum current angles of the r' wave fell into the northwest axis in all BS patients as compared to having a right axis deviation in 19 of 21 RBBB patients (90.4%, p=0.001). In the magnetic field and current density vector maps during late repolarization, the BS group had a non-dipole pattern more frequently and a higher number of poles compared with the normal (p=0.001) and RBBB groups (p=0.001). CONCLUSIONS: During depolarization, the horizontal STAG location and maximum current angle of the r' wave were beneficial in differentiating BS from RBBB and normal. The magnetic dispersion was a more frequently observed finding in BS patients than in RBBB and normal patients during late repolarization. (+info)
Efficacy of pulmonary vein isolation in paroxysmal atrial fibrillation patients with a Brugada electrocardiogram.
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BACKGROUND: Medical therapy of atrial fibrillation (AF) can be challenging in patients with Brugada electrocardiograms (ECGs). The purpose of this study was to investigate the efficacy of pulmonary vein (PV) isolation (PVI) in AF patients with Brugada ECGs. METHODS AND RESULTS: PVI was performed in 6 consecutive patients exhibiting Brugada ECGs (type I in 1, type II in 4, and type III in 1) at baseline. In all patients exhibiting type II or III Brugada ECGs but 1, the administration of sodium-channel blockers converted those ECG patterns to a type I. Five of 6 (83%) patients were free of symptomatic AF without any antiarrhythmic drugs after the first procedure. In the 1 remaining patient with AF recurrence and newly developed atrial tachycardia (AT), the residual conduction gaps of the 3 previously isolated PVs and a focal AT originating from the mitral isthmus were eliminated in the 2nd session. Finally, during the follow-up period (11+/-6 months) after the last procedure, all patients were free of any symptomatic atrial arrhythmias without any antiarrhythmic drugs. No other complications occurred. CONCLUSIONS: Because of the concerns of proarrhythmias with antiarrhythmic drugs, PVI may be an effective strategy for highly symptomatic patients with AF who have a Brugada ECG pattern. (+info)
Analyses of a novel SCN5A mutation (C1850S): conduction vs. repolarization disorder hypotheses in the Brugada syndrome.
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