ABSTRACT
Ischaemic heart disease especially after previous myocardial infarction can predispose to the life-threatening ventricular arrhythmias. Late potentials (LP) are confirmed parameters predicting patients prone to sudden cardiac death in ventricular arrhythmias mechanism. Late potentials registered noninvasively from the body surface were analysed in 86 patients with stable ischaemic heart disease (67 males and 19 females aged 35-67, mean 53 years). Registration of signal average electrocardiograms (SA-ECG) were performed by Simson technic (X, Y, Z orthogonal leads) using identical analysing systems and quantitative SA-ECG criteria in all three participating centers. In all patients ventricular arrhythmias detected on 24-hour ecg Holter monitoring were assessed. The localisation of previous myocardial infarction and echocardiographic assessment of left ventricular function were also analysed in each case. The results of SA-ECG were correlated with these clinical findings. Late potentials were detected (according to two or three accepted criteria) in 16 pts (19%), in 53 pts (61%) SA-ECG were normal but in other 17 pts (20%) abnormal SA-ECG (according to only one criterium) were registered. Out of these 17 pts with abnormal SA-ECG, 14 pts had prolonged filtered QRS duration as the only incorrect SA-ECG parameter. Comparative analysis between studied groups shows higher incidence of previous Q-wave myocardial infarctions in patients with LP and with abnormal SA-ECG than in patients with normal SA-ECG (63% and 71% vs 43% respectively; p less than 0.01). Ventricular arrhythmias observed in studied patients occurred with similar frequency in all groups however in patients with LP and with abnormal SA-ECG complex ventricular arrhythmias were more common than in group with normal SA-ECG (56% and 53% vs 49% respectively: NS).(ABSTRACT TRUNCATED AT 250 WORDS)
