Bosentan does not improve pulmonary hypertension and lung remodeling in heart failure

Pulmonary hypertension (PH) and right ventricular (RV) dysfunction associated with heart failure (HF) carry a poor prognosis. Although endothelin receptor antagonists (ERAs) demonstrated benefits in pulmonary arterial hypertension, their efficacy in PH associated with HF was not specifically evaluated. 2 weeks after myocardial infarction (MI) rats received bosentan (100 or 200 mg·kg(-1)·day(-1)) or no treatment for 3 weeks. PH, RV hypertrophy and function as well as lung remodeling and function were evaluated. LV echocardiographic wall motion abnormality and function measured before treatment (2 weeks after MI) and after treatment (5 weeks after MI) were similar in MI control and MI treatment groups. HF induced PH and RV hypertrophy compared with sham: RV systolic pressure 39±5 versus 23±0.8 mmHg and RV/left ventricular+septum weight 52±7 versus 24±0.5% (all p