RESUMO
Hypertrophic cardiomyopathy (HCM) is a heterogeneous disease, characterized by asymmetric hypertrophy of the left and/or right ventricle with disarray of myocardial fibers. In order to know its clinical and electrocardiographic manifestation in the pediatric age group, we made a retrospective study of 24 cases from 1986 to 1995. There were: 15 girls and 9 boys, with a mean age of 6 years (age range: 1 month to 17 years). Clinical manifestations were dyspnea (71%), syncope (42%) and palpitations (42%). Physical examination disclosed an aortic systolic murmur in all patients, a mitral regurgitation in 42% and physical signs of congestive heart failure in 54% of patients. Chest X rays showed cardiac enlargement in 71% and pulmonary capillary hypertension in 42%. The most frequent ECG abnormalities were: a prolonged time in the intrinsecoid deflection onset on leads corresponding to the affected region, more or less deep and clean Q waves on leads aVF, aVL, V5 and V6, as well as supraventricular and ventricular rhythm disturbances in 11 patients (46%) with and without congestive heart failure. Bidimensional echocardiography confirmed antero-septal hypertrophy in all patients. The mortality rate was 17%. HCM is rare disease in the pediatric age group. Mortality increases when congestive heart failure and arrhythmias are present. Treatment must be individualized in all cases.
Assuntos
Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/fisiopatologia , Adolescente , Cardiomiopatia Hipertrófica/complicações , Criança , Pré-Escolar , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Hipertrofia Ventricular Esquerda/complicações , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/fisiopatologia , Lactente , Masculino , Estudos RetrospectivosRESUMO
From 250 consecutive patients who underwent radiofrequency ablation of accessory pathways, we studied 102 patients with successful ablation of a single overt accessory pathway. All patients had manifested preexcitation on a baseline 12 lead electrocardiogram. None of this patients had additional congenital or acquired cardiac abnormalities which could have affected the QRS morphology. A new algorithm for localizing the AP site was developed, based only on the polarity of the QRS complexes in DIII, V1 and V2, without analysis of the delta wave. We could localize the accessory pathway in five sites with 88% of probability of success. This simplify the electrocardiographic analysis of Wolff Parkinson White and improvement the results of radiofrequency ablation.
Assuntos
Algoritmos , Eletrocardiografia/métodos , Sistema de Condução Cardíaco/anormalidades , Adolescente , Adulto , Idoso , Teorema de Bayes , Ablação por Cateter/instrumentação , Ablação por Cateter/métodos , Criança , Pré-Escolar , Eletrocardiografia/estatística & dados numéricos , Eletrofisiologia , Feminino , Sistema de Condução Cardíaco/fisiopatologia , Sistema de Condução Cardíaco/cirurgia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Prognóstico , Sensibilidade e Especificidade , Síndrome de Wolff-Parkinson-White/diagnóstico , Síndrome de Wolff-Parkinson-White/fisiopatologia , Síndrome de Wolff-Parkinson-White/cirurgiaRESUMO
Two hundred twenty two consecutive patients with acute myocardial infarction were followed for one year. We evaluated the usefulness of late potentials, the spectral analysis, heart rate variability, infarct-related coronary artery, ejection fraction, arrhythmias during Holter monitoring and other clinical variables as risk markers for developing of ventricular arrhythmias and/or sudden death. Twenty four patients (10.8%) had late arrhythmic events: sudden death in 7, sustained ventricular tachycardia in 15 and unexplained syncope in 2. Late potentials had high sensitivity (94%) and negative predictive value (99%), followed by an occluded related-infarct coronary artery (75% sensitivity and 96% negative predictive value). Complex ventricular arrhythmias during Holter monitoring was the test with the highest specificity (92%). A combination of late potentials plus an occluded infarct-related coronary artery or late potentials plus ejection fraction showed 100% sensitivity with 100% negative predictive value. Of the 16 studied variables, 5 had independent and significative value as a predictor of arrhythmic events, these are, according to the relative risk: late potentials (20.2), ejection fraction less than 40% (12.1), complex arrhythmias during Holter monitoring (7.5), the presence of an occluded infarct-related coronary artery (6.4) and anterior myocardial infarction localization (4.5). We consider, that with a combination of simple methods of assessment, we can select a subgroup of survivors of an acute myocardial infarction at high risk of developing ventricular arrhythmias and sudden death, which also identifies patients with low risk for these complications.
Assuntos
Arritmias Cardíacas/diagnóstico , Infarto do Miocárdio/complicações , Idoso , Arritmias Cardíacas/etiologia , Morte Súbita/etiologia , Eletrocardiografia , Eletrocardiografia Ambulatorial , Feminino , Testes de Função Cardíaca , Ventrículos do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
The most common cause of sudden death is malignant ventricular arrhytHmia. In order to identify the predictive value of the vectospatial evaluation in the surface electrocardiogram during a monomorphic ventricular tachycardia (MVT), and the equilibrium state of AutonomOus Nervous System (ANS), 89 patients of both sexes were studied with mean age of 47 +/- 16.2 years. They were grouped as follows: Group I included 43 patients (P), with a coronary heart disease; Group II (n = 24P) with a noncoronary myocardiopathy and Group III (n = 22P) with unknown origin MVT (Cryptogenic). Relationship between QRS configuration in the frontal plane (QRSf) during MVT episode with transverse plane, cardiac position in the chest X-rays, presence and duration of late potentials (LPs) in their two types of analysis (time domain and spectral mapping by high-resolution electrocardiogram), heart rate variability and ejection fraction by echocardiography were determined in all patients. The QRSf configuration with left bundle-branch block (LBBB) was the most common in group I, the sustained MVT (SMVT) + LBBB was associated with both prevalence and duration of late potentials (p = 0.005), low-rate heart variability and ejection fraction < 40%. SMVT + LBBB was the most common type in group III and if it has shown and inferior axis, an elevated rate of LPs (+) was seen. Situation that oriented to an arrhythmogenic right ventricular dysplasia. Low amplitude signals with short duration in the time domain were seen in group I with LBBB; and with SMVT + RBBB in group II. We suggest that vectospatial evaluation of QRSf during a MVT is a greater importance in the risk stratification for sudden death and it can guide to anatomic origin and the diagnosis-therapeutic approach.