Effect of propranolol on left ventricular systolic and diastolic function in patients with atrioventricular block in early period after pacemaker implantation

Propranolol was given short-term after VVI pacemaker implantation because o f atrioventricular block to 28 patients with hypertension and clinical sign s of heart failure. No drug therapy was used in control group which compris ed 28 patients with atrioventricular block and implanted pacemakers. After treatment with propranolol duration of systole and phase of isometric contr action significantly increased. Ejection time did not change while maximal ejection velocity decreased. Lengthening of systole under conditions of fix ed heart rate and therefore constant duration of the cardiac cycle led to s hortening of diastole at the account of decreased filling time. Maximal fil ling velocity also significantly decreased. Thus in patients with atriovent ricular block and VVI pacemaker the use of propranolol was associated with worsening of left ventricular systolic and diastolic function. Early after pacemaker implantation this could be revealed only by the analysis of param eters of intracardiac hemodynamics. Meanwhile parameters of central hemodyn amics reflected alterations caused by pacing and were not affected by the a ction of propranolol.