[Vector cardiographic evaluation of monomorphic ventricular tachycardia; its relation to the type of cardiopathy, vagal tonus and the prevalence of late potentials].
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.
Rosas Peralta
M
M
Depto. de Electrocardiografía y Electrofisiología, Instituto Nacional de Cardiología Ignacio Chávez, México, D.F.
Casanova Garcés
J M
JM
González Hermosillo
J A
JA
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D009202:Cardiomyopathies / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D003645:Death, Sudden; D004562:Electrocardiography / Q000379:methods* / Q000706:statistics & numerical data; D005260:Female; D006321:Heart / Q000503:physiopathology; D006339:Heart Rate; D006801:Humans; D008297:Male; D008564:Membrane Potentials; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D014630:Vagus Nerve / Q000503:physiopathology*; D014672:Vectorcardiography
Evaluación vecto-espacial de la taquicardia ventricular monomórfica; relación con el tipo de cardiopatía, tono vagal y prevalencia de potenciales tardíos.