Effects of bosentan, sildenafil and their combination on T-wave amplitude and QT ınterval in a rat model of pulmonary hypertension

Abstract

Aim: Although, bosentan and sildenafil have been used to treat PAH, the effect of these drugs on electrocardiographic (ECG)changes are still unclear. The aim of this study is to evaluate the effects of bosentan, sildenafil, and their combination on T-waveamplitude and QT interval in rats with monocrotaline (MCT)-induced PAH.Materials and Methods: Saline (control) or MCT were applied to sixty-six male Wistar rats. By the development of PAH (4th week),MCT-given rats were randomized into 4 groups and were treated orally with bosentan, sildenafil and combination of sildenafil andbosentan or placebo for 3 weeks. Echocardiographic (ECHO) and ECG examinations were performed three times on baseline, 4thand 7th week.Results: ECHO results showed that the application of MCT developed PAH in all injected rats. Usually, T-wave changes and QTcprolongation in ECG began after PAH and T-wave amplitudes, T-repolarization time as well as QTc intervals significantly increasedin all groups after treatment (p