Zacà F, Ghinelli M, Bombardini T, De Collibus C, Zaccaria O, Steffanon L, Azzolini U, Valentini P, Puddu P
Istituto di Patologia Speciale Medica e Metodologica Clinica, Ospedale S. Orsola, Bologna.
G Ital Cardiol. 1990 Jun;20(6):569-75.
Reduced left ventricular function and ventricular arrhythmias are the main risk factors associated with sudden death in patients with previous acute myocardial infarction. Antiarrhythmic therapy may have side-effects on myocardial contractility and sometimes makes the arrhythmia itself worse, especially when the pump function is seriously compromised. The aim of this study was to evaluate the efficacy of oral mexiletine as well as any modifications in left ventricular function by means of ambulatory ECG monitoring and angiocardiography with Tc 99m, at rest and after the handgrip test, in 20 patients with previous myocardial infarction and ventricular arrhythmias who were grouped into NYHA class II and class III. The mexiletine therapy lasted three weeks. Both classes showed a significant decrease in the number of ventricular extrasystoles/hour and in the number of couples (p less than 0.01). The decrease in the number of the ventricular runs proved to be higher in the general analysis (p less than 0.01) than in each NYHA class (p less than 0.05). At the end of the study, significant modifications were not observed either in the end-diastolic and end-systolic volumes, or in the ventricular ejection fraction.
左心室功能减退和室性心律失常是既往有急性心肌梗死患者猝死的主要危险因素。抗心律失常治疗可能对心肌收缩力有副作用，有时会使心律失常本身恶化，尤其是当泵功能严重受损时。本研究的目的是通过动态心电图监测以及静息和握力试验后用锝99m进行心血管造影，评估口服美西律的疗效以及对20例既往有心肌梗死和室性心律失常且分为纽约心脏协会（NYHA）II级和III级患者左心室功能的任何改变。美西律治疗持续三周。两组患者每小时室性早搏数量和成对早搏数量均显著减少（p<0.01）。在总体分析中，室性心动过速发作次数的减少（p<0.01）比在每个NYHA级别中更显著（p<0.05）。研究结束时，舒张末期和收缩末期容积以及心室射血分数均未观察到显著改变。
