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P Brugada

Publications and source records attributed to P Brugada.

At least 19 recordsLinked to original sources

Right bundle branch block, persistent ST segment elevation and sudden cardiac death: a distinct clinical and electrocardiographic syndrome. A multicenter report.

OBJECTIVES: The objectives of this study were to present data on eight patients with recurrent episodes of aborted sudden death unexplainable by currently known diseases whose common clinical and electrocardiographic (ECG) features define them as having a distinct syndrome different from idiopathic ventricular fibrillation. BACKGROUND: Among patients with ventricular arrhythmias who have no structural heart disease, several subgroups have been defined. The present patients constitute an additional subgroup with these findings. METHODS: The study group consisted of eight patients, six male and two female, with recurrent episodes of aborted sudden death. Clinical and laboratory data and results of electrocardiography, electrophysiology, echocardiography, angiography, histologic study and exercise testing were available in most cases. RESULTS: The ECG during sinus rhythm showed right bundle branch block, normal QT interval and persistent ST segment elevation in precordial leads V1 to V2-V3 not explainable by electrolyte disturbances, ischemia or structural heart disease. No histologic abnormalities were found in the four patients in whom ventricular biopsies were performed. The arrhythmia leading to (aborted) sudden death was a rapid polymorphic ventricular tachycardia initiating after a short coupled ventricular extrasystole. A similar arrhythmia was initiated by two to three ventricular extrastimuli in four of the seven patients studied by programmed electrical stimulation. Four patients had a prolonged HV interval during sinus rhythm. One patient receiving amiodarone died suddenly during implantation of a demand ventricular pacemaker. The arrhythmia of two patients was controlled with a beta-adrenergic blocking agent. Four patients received an implantable defibrillator that was subsequently used by one of them, and all four are alive. The remaining patient received a demand ventricular pacemaker and his arrhythmia is controlled with amiodarone and diphenylhydantoin. CONCLUSIONS: Common clinical and ECG features define a distinct syndrome in this group of patients. Its causes remain unknown.

Adult

Incidence, pathophysiology and prognosis of exercise-induced sustained ventricular tachycardia associated with healed myocardial infarction.

Of 150 consecutive patients with sustained monomorphic ventricular tachycardia (VT) (n = 116) or ventricular fibrillation (VF) (n = 34) late after acute myocardial infarction, 17 had reproduction of their sustained monomorphic VT during exercise testing. Data from these patients (group I) were compared with data from patients without exercise-induced VT (group II). No statistical difference was found between groups I and II with relation to age, sex, number of vessels with greater than 70% stenosis, left ventricular ejection fraction, number of previous myocardial infarctions, inducibility during programmed stimulation and total mortality during follow-up. In group I, only 1 patient (6%) developed ST depression during exercise compared with 47 patients (35%) in group II (p less than 0.01). After a 34-month mean follow-up, 6 patients in group I (35%) and 18 patients in group II (13%) died suddenly (p = 0.02). It is concluded that sustained monomorphic VT is reproduced during exercise in only 11% of patients with spontaneous late sustained monomorphic VT or VF. Electrocardiographic findings do not support ischemia as a triggering mechanism of exercise-induced sustained monomorphic VT. Patients with exercise-induced sustained monomorphic VT have a high incidence of sudden death.

Coronary Angiography

Incidence and timing of recurrences of sudden death and ventricular tachycardia during antiarrhythmic drug treatment after myocardial infarction.

Incidence and timing of recurrences of sustained ventricular tachycardia (VT) or sudden death were studied in 206 patients who survived their first episode of ventricular fibrillation (VF; n = 52) or sustained VT (n = 154) after myocardial infarction. All patients were treated with (empirically selected) antiarrhythmic drugs; 49% received amiodarone. After a mean follow-up of 36 months, 64 patients (41%) in the VT group and 10 (19%) in the VF group had nonfatal VT recurrences. Sudden death occurred in 22 (14%) and 9 (17%) patients in the VT and VF groups, respectively. Incidence of sudden death had 2 peaks at approximately 3 and 12 months. Nonfatal VT recurrences were more frequent (most often occurring in first 6 months) in the VT than in the VF group. Sudden death occurred during the following 3 years in only 10% of patients who survived 1 year. There was a much higher incidence of sudden death in patients with left ventricular ejection fraction (LVEF) less than or equal to 40% than in those with LVEF greater than 40% (28 of 65 vs 3 of 141; p less than 0.0001), but no relation between LVEF and nonfatal VT recurrences.

Aged

Identification of patients at high risk for recurrence of sustained ventricular tachycardia after healing of acute myocardial infarction.

A prognostic index for nonfatal recurrences of ventricular tachycardia (VT) was developed using a retrospective analysis of a group of 206 patients with sustained monomorphic VT or ventricular fibrillation (VF) after healing of acute myocardial infarction. 74 patients (36%) (64 with VT and 10 with VF) had recurrences of sustained monomorphic VT during 3.4 +/- 9 years of follow-up. Three clinical variables were selected and weighted by stepwise logistic discriminant analysis of the study group. They were coded as follows: interval of myocardial infarction to arrhythmia (less than 2 months = 1; 2 to 6 months = 2; greater than 6 months = 3), drug therapy with or without sotalol (with = 1, without = 2), and VT or VF as the presenting arrhythmia (VT = 1, VF = 2). The prognostic index was: 3.41 - (0.56 x interval) - (1.94 x therapy) + (0.86 x arrhythmia). This index was validated prospectively in a test group of 158 consecutive patients with VT or VF after healing of acute myocardial infarction. Patients were allocated into different classes with decreasing prognostic index values associated with increasing risk for recurrences of VT. In the test group, 27 of 158 (17%) patients (22 with VT and 5 with VF) had recurrences of VT (follow-up of 2 +/- 2 years). Two risk classes of patients were identified: high risk for recurrences of VT (61%) corresponding to patients with a negative index; and low risk (4%) consisting of those with a positive index. Thus, using O as the cutoff point, the sensitivity, specificity, and positive and negative predictive values were 81, 89, 62 and 96%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Which ventricular tachycardia is dangerous?

The treatment of ventricular arrhythmias remains a major challenge in cardiology. Several very helpful pieces of information can be obtained from the clinical history. The left ventricular function and the hemodynamic effects of a ventricular tachycardia are the two main factors affecting survival. Therefore, if a patient with sustained ventricular tachycardia presents with syncope or cardiac arrest, or if his functional class for dyspnea is III-IV (NYHA classification), he is a candidate for an implantable defibrillator while otherwise medical therapy is advised.

Decision Trees

The electrocardiographic, clinical, and electrophysiologic spectrum of idiopathic monomorphic ventricular tachycardia.

Clinical, ECG, and electrophysiologic data from 47 patients who had episodes of sustained or nonsustained monomorphic VT with no evidence of structural heart disease were reviewed. According to the QRS configuration during tachycardia, four groups were distinguished. Nine patients had a right bundle branch block configuration and superior frontal plane QRS axis (group 1). Nine patients had a right bundle branch block configuration but an intermediate or right QRS axis (group 2). Group 3 consisted of five patients with a left bundle branch block configuration and a left axis deviation, and in group 4 there were 24 patients who had a left bundle branch block configuration with an intermediate or right frontal axis. Patients in group 1 had dizziness during tachycardia less frequently, but they needed cardioversion to terminate their arrhythmias more often. They experienced tachycardia during exercise less often, and tachycardia was not initiated during exercise testing. They had fewer ventricular premature beats according to the Holter recording. During the electrophysiologic study, VT was induced and terminated by pacing more often in this group. Patients with idiopathic VT with a right bundle branch block configuration and a superior axis seem to be a unique group of patients with idiopathic VT, and reentry seems to be the most likely arrhythmia mechanism in this group. The other ECG configurations share the same clinical and electrophysiologic characteristics, which suggest that the underlying arrhythmia mechanism is the same.

Adult

Right-sided versus left-sided radiofrequency ablation of the His bundle.

UNLABELLED: Radiofrequency (RF) ablation of the His bundle was attempted in 30 consecutive patients with atrial flutter or fibrillation. A 7 French quadripolar catheter with a 4-mm distal electrode was advanced from the right femoral vein (21 patients), or subclavian vein (two patients) and positioned across the tricuspid valve. Adequate His-bundle potentials were obtained in all patients. However, in six patients atrioventricular (AV) block could not be obtained after multiple (mean = 8) applications of RF energy from the conventional right-sided approach. In these patients the same catheter was advanced to record a His potential through a retrograde arterial approach. AV block was created in all patients with one to three applications of RF energy. The duration of the procedure was 22 to 90 minutes for the right-sided approach and 5 to 10 for the left-sided approach (P < 0.005). Subsequently, in seven patients a left-sided approach was used first. One to six applications of RF energy were required to create AV block. The radiation exposure time was 3 to 20 minutes. No complications occurred. CONCLUSIONS: RF ablation of the His bundle seems easier using a left-sided than a right-sided approach, reduces procedure and radiation time, and avoids recovery of conduction. These data suggest that a left-sided approach, in spite of requiring arterial catheterization, may be preferable to a right-sided approach.

Atrial Fibrillation

Radiofrequency ablation of symptomatic but benign ventricular arrhythmias.

Two cases are presented where ablation of severely symptomatic ventricular arrhythmias not responding to medical therapy was accomplished with radiofrequency current application. After a routine programmed stimulation protocol, a quadripolar ablation catheter with a 4-mm tip was advanced percutaneously into the left ventricle in one case and into the right ventricle in the second case; and after precise pace mapping, the arrhythmogenic focus was successfully ablated using radiofrequency current. The postablation ambulatory recording revealed virtual eradication of ventricular ectopy in both cases. In conclusion, in severely symptomatic cases of "benign" ventricular arrhythmias, radiofrequency ablation offers an effective therapeutic alternative.

Adult

[Supraventricular tachycardia due to retrograde decremental conduction over accessory pathways].

PURPOSE: To discuss the clinical and the electrophysiologic findings, the differential diagnosis and the behaviour of concealed retrograde long conduction time accessory pathways. METHODS: Seventeen patients were submitted to electrophysiologic study using programmed electrical stimulation of the heart to assess the electrophysiologic properties of the accessory pathway. RESULTS: In all 17 studied patients, it was possible to advance the next atrial activation by giving a ventricular premature beat during the refractoriness of the His bundle. Of 17 patients, 7 developed signs and symptoms of heart failure (tachycardia-induced cardiomyopathy) due to the presence of incessant tachycardia. Eight patients were cured surgically and 1 underwent DC catheter ablation of the AV node. Six patients were successfully treated with antiarrhythmic drugs, one die of cancer and one still presents incessant tachycardia. CONCLUSION: The electrophysiologic study is essential for the differential diagnosis of the supraventricular tachycardias with a R-P' interval longer than P'-R interval where the incidence of tachycardiomyopathy is high in this group of patients. Surgery provides definitive cure of those patients leading to the regression of the signs and symptoms of heart failure.

Adolescent

Transcoronary chemical ablation of arrhythmias.

BACKGROUND: Chemical or electrical ablation of an arrhythmogenic ventricular area and the atrioventricular (AV) node is still an experimental technique. After we introduced alcohol ablation in the clinical situation we conducted this study to develop the catheter technique for delivering alcohol in patients with incessant ventricular tachycardia after myocardial infarction and patients with atrial fibrillation and flutter with uncontrollable ventricular rates. METHODS: In patients with incessant ventricular tachycardia, the coronary artery supplying blood to the site of origin of the tachycardia could be identified by the combined information from coronary and left ventricular angiography and from programmed electrical stimulation, including endocardial mapping and pace mapping. In the 12 patients with incessant ventricular tachycardia we selected, the coronary artery supplying blood to the site of origin of the tachycardia could be identified and catheterized in ten patients. Ethanol ablation was successful in all of them. With a follow-up from 2 to 44 months, seven of the ten treated patients are still alive and six remain free of tachycardia. In patients with atrial fibrillation or flutter and uncontrollable ventricular rates, the AV artery could be catheterized and ethanol injected in 13 of the 19 patients. Complete block was produced in ten patients and AV conduction was sufficiently modified to control symptoms in three patients. Long-term results with ethanol ablation have remained excellent in this setting. CONCLUSION: Chemical ablation is a technique that may be of enormous value and even lifesaving for patients with an incessant form of tachycardia not responding to any form of medical therapy. Transcoronary ablation of AV conduction should be considered in patients with a right dominant coronary circulation in whom radiofrequency ablation has failed.

Adult

Sudden arrhythmic death without overt heart disease.

Nine patients (eight males) are reported with one or more episodes of circulatory collapse in the absence of overt heart disease or other known causes of arrhythmias; sudden arrhythmic death occurred in one of these patients. Age at first episode ranged from 16 to 41 (mean, 28) years. In seven patients, ventricular fibrillation was documented at the time of resuscitation. One patient had ventricular flutter. In the remaining patient, documentation of the arrhythmia during the collapse was not available. Four patients had frequent early ventricular premature beats, and in three of these patients, they were accompanied by episodes of rapid nonsustained polymorphic ventricular tachycardia. Failure to suppress this ectopic activity by drug therapy seems to be of prognostic significance. Of the three patients showing persistence of frequent early ventricular premature beats, one died suddenly, and two had recurrences of symptomatic arrhythmic episodes. The value of noninvasive and invasive tests in the management of these patients is not clear, with the exception of exercise testing in patients with exercise-related arrhythmias and long-term electrocardiographic monitoring in patients with frequent spontaneous ventricular ectopic activity. Follow-up varied from 21 to 192 (mean, 84) months. One patient died suddenly 21 months after his first collapse. Selection of antiarrhythmic drug therapy was largely empirical. In view of the relative rarity of sudden arrhythmic death in the absence of heart disease and the many uncertainties about its mechanism(s) and management, a worldwide registry of these patients is suggested.

Adolescent

Clinical and electrophysiologic characteristics of exercise-related idiopathic ventricular tachycardia.

In 37 (70%) of 53 patients with idiopathic ventricular tachycardia (VT), episodes were mainly related to exercise (group 1). These patients were younger (33 +/- 14 vs 44 +/- 18 years, p = 0.015) and more often had dizziness during VT (71 vs 40%, p = 0.003) than the 16 patients in whom VT was not exercise-related (group 2). Patients in group 1 needed cardioversion less often to terminate the arrhythmia (4 (11%) vs 6 (40%), group 2 [p = 0.04]). VT was initiated during exercise testing in 62% of patients in group 1 but in only 1 patient in group 2 (p = 0.0004). Induction of clinical VT during programmed stimulation was observed in a similar percentage in group 1 (49%) and group 2 (50%) patients. Isoproterenol infusion facilitated the induction of VT in 9 of 20 (45%) group 1 and in 2 of 8 (25%) group 2 patients (p = not significant). After a mean follow-up of 2.9 +/- 2.5 years, 8 (22%) group 1 patients and 5 (31%) group 2 had at least 1 episode of symptomatic VT. Only 1 patient died suddenly. Class III drugs were the most useful in preventing recurrences. Beta-blocking agents were of little value in both groups. Patients with VT and a structurally normal heart have a good prognosis despite recurrences of their arrhythmia. The relation of the arrhythmia to exercise has no prognostic implications.

Adult

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Arrhythmias, Cardiac