Effects of sildenafil on cardiac structure and function, cardiopulmonary exercise testing and health-related quality of life measures in heart failure patients with preserved ejection fraction and pulmonary hypertension

Aims We recently showed that sildenafil did not improve pulmonary pressures and exercise capacity in a cohort of patients with heart failure and preserved ejection fraction (HFpEF) and predominantly postcapillary pulmonary hypertension. Here, we present the effects of sildenafil on cardiac structure and function, cardiopulmonary exercise testing, laboratory parameters and health-related quality of life measures. Methods and results Fifty-two HFpEF patients with pulmonary hypertension (mean pulmonary artery pressure > 25 mmHg; pulmonary artery wedge pressure > 15 mmHg) were randomized to sildenafil 60 mg three times a day or placebo and treated for 12 weeks. Sildenafil neither changed cardiac structure nor function on echocardiography compared with placebo. Considering all patients irrespective of maximal effort, sildenafil reduced peak heart rate by 8 b.p.m. [95% confidence interval (CI) -14.97 to -1.03] and peak blood pressure by 13.8mmHg (95% CI -22.04 to -5.47)/7.3mmHg (95% CI -13.60 to -1.07) (both P <0.05 vs. placebo). The minute ventilation/carbon dioxide production (VE/VCO2) slope remained unchanged in the sildenafil group (0.3, 95% CI -1.37-1.98), while it was reduced in the placebo group (-7.6, 95% CI -12.97 to -2.25, P = 0.002). In both groups, renal function improved and N-terminal pro-brain natriuretic peptide concentration reduced equally. Haemoglobin and glycated haemoglobin levels slightly decreased in the sildenafil group (P