[Primary research on the clinical significance of ventricular late potentials (VLPs), and the impact of mexiletine, lidocaine and Astragalus membranaceus on VLPs].

The body surface signal-averaged electrocardiogram (SAECG) was recorded on 316 cardiac patients, 84% (266 patients) of whom were also taken 24-hour Holter ECG. VLPs were detected positively in 6.1%, 25%, 25.7%, 14.3% and 5.5% of patients with angina pectoris, myocardial infarction, myocarditis, cardiomyopathy and arrhythmia of unknown origin respectively, and the patients with complex ventricular arrhythmia had more VLPs positive determination definitely (P less than 0.05). The specificity of VLPs in the prediction of complex ventricular arrhythmia was greater than 80%, and the positive predictive accuracy was 70-80%. 5, 5 and 10 patients with VLPs were treated with Mexiletini Hydrochloridum, Lidocaini Hydrochloridum and Injection of Astragalus membranaceus respectively. As a result of treatment, the transfer of VLPs positive to negative was unsuccessful, but only the intervention of Astragalus membranaceus Injection made the duration of VLPs shortened significantly (39.8 +/- 3.3 ms versus 44.5 +/- 5.9 ms, P less than 0.01).