[The evolution and clinical significance of the ventricular late potential in acute myocardial infarction]

Two hundred cases of acute myocardial infarction (AMI) who had survived for 2 or more weeks were studied consecutively. 96.5% had been followed up for 0.5-27 (average 13) months. Signal averaging with filter corner frequencies of 40-250Hz were used to record ventricular late potentials (VLP). During hospitalization, 26.5% had at least one positive VLP. There were no statistical differences in age, gender, CK-peak value, or LVEF prior to the discharge between positive and negative VLP groups. However, there were more positive cases in inferior wall infarction and Killip's grade II or above (P less than 0.05). More VT/VF cases in VLP positive group, but no statistical correlation between the VLP and ventricular arrhythmias in Holter recording. On follow-up, 2/3 positive cases turned out negative, but greater part in these with continuous positive VLP had obvious cardiac dysfunction and reinfarction.