Síncope / Syncope

Síncope é definida como a perda da consciência e do tônus postural, que ocorre secundariamente à hipoperfusão cerebral global, seguida de recuperação espontânea. As causas mais freqüentes em geral não causam danos aos pacientes, mas seu diagnóstico diferencial é importante porque os episódios de síncope de origem cardíaca podem ser preditores de morte súbita. A intenção deste artigo é abordar este tema e chamar a atenção para os casos mais graves.

Bloqueios de ramo e bloqueios atrioventriculares como complicaçöes do infarto agudo do miocárdio na era trombolítica / Bundle branch and atrioventricular block as complications of acute myocardial infarction in the thrombolytic era

OBJECTIVE: To analyze the incidence of intraventricular and atrioventricular conduction defects associated with acute myocardial infarction and the degree of in hospital mortality resulting from this condition during the era of thrombolytic therapy. METHODS: Observational study of a cohort of 929 consecutive patients with acute myocardial infarction. Multivariate analysis by logistic regression. Was used. RESULTS: Logistic regression showed a greater incidence of bundle branch block in male sex (odds ratio = 1.87, 95 per cent CI = 1.02-3.42), age over 70 years (odds ratio = 2.31, 95 per cent CI = 1.68-5.00), anterior localization of the infarction (odds ratio = 1.93, 95 per cent CI = 1.03-3.65). There was a greater incidence of complete atrioventricular block in inferior infarcts (odds ratio = 2.59, 95 per cent CI 1.30-5.18) and the presence of cardiogenic shock (odds ratio = 3.90, 95 per cent CI = 1.43-10.65). Use of a thrombolytic agent was associated with a tendency toward a lower occurrence of bundle branch block (odds ratio = 0.68) and a greater occurrence of complete atrioventricular block (odds ratio = 1.44). The presence of bundle branch block (odds ratio = 2.45 95 per cent , CI = 1.14-5.28) and of complete atrioventricular block (odds ratio = 13.59, 95 per cent CI = 5.43-33.98) was associated with a high and independent probability of inhospital death. CONCLUSION: During the current era of thrombolytic therapy and in this population, intraventricular disturbances of electrical conduction and complete atrioventricular block were associated with a high and independent risk of inhospital death during acute myocardial infarction.

Uso de marcapasso provisório e definitivo em pacientes submetidos a transplante cardíaco ortotópico / Permanent and temporary pacemaker implantation after orthotopic heart transplantation

PURPOSE:To determine the indication for and incidence and evolution of temporary and permanent pacemaker implantation in cardiac transplant recipients. METHODS: A retrospective review of 114 patients who underwent orthotopic heart transplantation InCor (Heart Institute USP BR) between March 1985 and May 1993. We studied the incidence of and indication for temporary pacing, the relationship between pacing and rejection, the need for pemanent pacing and the clinical follow-up. RESULTS: Fourteen of 114 (12 per cent) heart transplant recipients required temporary pacing and 4 of 114 (3.5 per cent) patients required permanent pacing. The indication for temporary pacing was sinus node dysfunction in 11 patients (78.5 per cent) and atrioventricular (AV) block in 3 patients (21.4 per cent). The indication for permanent pacemaker implantation was sinus node dysfunction in 3 patients (75 per cent) and atrioventricular (AV) block in 1 patient (25 per cent). We observed rejection in 3 patients (21.4 per cent) who required temporary pacing and in 2 patients (50 per cent) who required permanent pacing. The previous use of amiodarone was observed in 10 patients (71.4 per cent) with temporary pacing. Seven of the 14 patients (50 per cent) died during follow-up. CONCLUSION: Sinus node dysfunction was the principal indication for temporary and permanent pacemaker implantation in cardiac transplant recipients. The need for pacing was related to worse prognosis after cardiac transplantation.

Morbimortalidad asociada a bloqueo auriculoventricular en el infarto del miocardio de pared inferior / Morbidity and mortality in atriventricular block of acute inferior wall myocardial infarction

El infarto del miocardio (IAM) de pared inferior, complicado con bloqueo auriculoventricular (BAV) se asocia a mayor mortalidad a pesar de ser en muchos casos transitorio. Con el objeto de analizar las causas de esta mayor mortallidad se estudiaron 307 pacientes (pts) consecutivos con IAM inferior, dividiéndolos en 421 pts sin BAV (grupo I) y 66 pts con BAV de 2o. ó 3o. grado (grupo II). La mortalidad global fue 10.7 (8.3% grupo I, p<0.001). No encontramos diferencias en ambos grupos respecto a factores de riesgo (excepto para tabaquismo, que fué mayor en el grupo I, p<0.001), antecedente de IAM, angina crónica o insuficiencia cardíaca previa. Encontramos diferencias significativas en ambos grupos respecto a edad (61 ñ 12 grupos I vs 68 ñ 9 años grupo 2, p<0.001) y en niveles máximos de CPK x ñ DS (1513 ñ 1135 grupo I vs 1958 ñ 1293 UI/1 grupo II, p<0.01). Durante su evolución los pacientes del grupo II presentaron mayor incidencia de arritmias ventriculares complejas, (p<0.01), de arritmias supraventriculares p<0.01) y de insuficiencia cardíaca Killip III y IV, (p<0.0001). Se estudiaron 123 pts con coronariografía, 106 del grupo I y 17 pts del grupo II. En los pts con BAV se encontró mayor incidencia de enfermedad de 3 arterias (47% vs 28%) y de lesiones críticas asociadas de arterias descendente anterior y derecha (29% vs 12%, p<0.06). En conclusión, los pts con IAM inferior complicado de BAV tienen mayor mortalidad en relación a edad más avanzada, necrosis más extensa, más complicaciones asociadas, y mayor incidencia de lesiones asociadas de arterias descendente anterior y derecha