COMPARED EFFECTS OF SOTALOL, FLECAINIDE AND PROPAFENONE ON VENTRICULAR REPOLARIZATION IN PATIENTS FREE OF UNDERLYING STRUCTURAL HEART-DISEASE

Antiarrhythmic drugs are known to affect the depolarization and repola rization time in a different fashion. The aim of the present study was to compare the effects of Sotalol, Flecainide and Propafenone on some common (QT, QTc, JT, JTc) or uncommon (QTc dispersion, T-peak to T-en d interval) electrocardiographic parameters in order to evaluate the e ffects of these antiarrhythmic drugs on ventricular repolarization tim e both in terms of absolute values and of dispersion across the myocar dium. The analysis of these antiarrhythmic drug effects was performed on the standard 12-lead electrocardiograms of 31 patients (17F and 14M , age 38.1+/-17 years, range 11-67 years) in the free-drug state and a t the steady state after oral treatment with Sotalol (160 mg daily), F lecainide (200 mg daily) and Propafenone (450 mg daily). These drugs w ere prescribed, separately, to all the 31 patients, free of underlying structural heart disease, for the treatment of their atrio-ventricula r nodal re-entry tachycardia Data of the present study show that Sotal ol, over the range prescribed, significantly prolongs ventricular repo larization index QT (P=0.001), JT (P=0.0001) and JTc (P=0.0001) values in an homogeneous fashion, as shown by the significant decrease in QT cD (P=0.019) and Tp-Te (P=0.01). On the contrary, Flecainide treatment was associated with an increase in QTcD (P=0.029), Tp-Te (0.0001), QT (P=0.001), QTc (P=0.0001) and QRS (P=0.0001), with no significant cha nges in JT and JTc. Propafenone, over the range prescribed, did not af fect repolarization time, resulting only in a prolongation of depolari zation time as expressed by the increase of QRS (P=0.0001). (C) 1998 E lsevier Science Ireland Ltd. All rights reserved.