[Characteristics of non-sustained ventricular tachycardia found during dynamic ECG in patients with recent myocardial infarction]

The characteristics of ventricular tachycardia found during Holter ECG monitoring before discharge in patients hospitalized because of acute myocardial infarction were analyzed. One or more ventricular tachycardia episodes were found in 29 of 251 patients (11.5%). On the whole, there were 233 episodes of ventricular tachycardia: 18 patients (62%) had only one episode of ventricular tachycardia, 9 (31%) 2-5 episodes and 2, respectively, 68 and 118 episodes. Episodes of ventricular tachycardia were more numerous in patients with frequent or polymorphic premature ventricular complexes than in patients with sporadic or monomorphic premature ventricular complexes. Fifty-seven ventricular tachycardia episodes were analyzed: 30 of 3 beats, 25 of 4-9 beats and 2 of 15 beats. Forty-seven episodes were monomorphic and 10 (17.5%) were polymorphic. The ventricular tachycardia rate was 136.4 +/- 25 b/m' (range 104-200). The RR'/QT ratio (where RR' = coupling interval of the first beat of ventricular tachycardia) was 1.67 +/- 0.42 and was not correlated either with the rate or the number of beats of ventricular tachycardia. Heart rate at the moment of ventricular tachycardia was 82 +/- 15 b/m' and QT interval 0.36 +/- 0.05 sec; there was no difference when compared to their values of 1 and 5 minutes before ventricular tachycardia. Furthermore, the heart rate showed no difference when compared to the mean value of the hours in which ventricular tachycardia episodes occurred. In addition, heart rate was not correlated with ventricular tachycardia rate, whereas a good correlation was found between the last RR interval preceding ventricular tachycardia and RR' interval (r = 0.61, P less than 0.01).