[Programmed ventricular stimulation in the evaluation of the clinical significance of premature ventricular contractions].

The authors subjected 34 patients (27 men and 7 women) to invasive electrophysiological examination. All patients had early ventricular contractions class 3-5 according to Lown which were recorded during ECG monitoring in bed or by Holter's system. A pathological excitability of the ventricular myocardium was found during programmed stimulation in 29% of the subjects. The excitability of the heart muscle was substantially enhanced by the incidence of ischaemic heart disease and reduced left ventricular function. The decreased frequency and severity of early ventricular contractions during bicycle ergometry, the absence of palpitations and syncopes increases the probability of normal excitability of the ventricular myocardium.