[The effect of disopyramide, mexiletine and propafenon after intravenous and oral administration on left ventricular function in the M-mode echocardiogram].

The effects of the antiarrhythmic drugs disopyramide (D), mexiletine (M), and propafenone (P) on left ventricular function after intravenous injection and after oral therapy of at least 48 hours, and of the combined oral application of D and M, were studied by M-mode echocardiography in patients with ventricular arrhythmias in whom antiarrhythmic therapy was indicated. The drugs were given in doses comparable in terms of clinical efficacy. The results showed that the three drugs had varying negative inotropic power. The intravenous injection resulted in a more pronounced cardiac depression than the oral therapy. The most significant decrease in left ventricular wall motion after intravenous and oral application was seen after D, the smallest negative inotropic effect after M. P caused a cardiac depression between these extremes. After the combined oral application of D and M the impairment of left ventricular function was more pronounced than after therapy with the single drugs.