[Clinical characteristics of chronic recurrent ventricular tachycardia]

The clinical characteristics of chronic recurrent ventricular tachycardia were studied in 47 patients. In 28 patients out of them, no underlying heart diseases were found (NHD group). The remaining 19 patients were diagnosed as having cardiomyopathy, old myocardial infarction, or other underlying heart diseases (HD group). NHD group showed a lower mean age and higher female proportion than the HD group. Nine patients (32%) in NHD group and 13 patients (68%) in HD group showed sustained ventricular tachycardia. Adams-Stokes attack was observed in 70% of this patient series, and was highly related to the tachycardia rate and sustainability. Ventricular tachycardia in the NHD group showed a faster heart rate and narrower QRS duration than in the HD group. Characteristic QRS configurations during ventricular tachycardia ("CRBBB + LAD" pattern or "CLBBB + inferior axis" pattern) were demonstrated in the NHD group, while no consistent QRS pattern was observed in the HD group. Electrical induction of ventricular tachycardia was only successful in patients with sustained ventricular tachycardia, mainly in the HD group. On the other hand, treadmill testing was more likely to provoke ventricular tachycardia in the NHD group than in the HD group. Poor prognosis was noted in patients in the HD group (7 deaths in the 4-month to 10-year follow up period), while there were no cardiac deaths in the NHD group. These results suggest that the QRS pattern during ventricular tachycardia and the response to electrical induction and treadmill testing may play an important role in predicting the prognosis of patients with chronic recurrent ventricular tachycardia.