Sildenafil for improving outcomes in patients with corrected valvular heart disease and persistent pulmonary hypertension: a multicenter, double-blind, randomized clinical trial

Aims We aimed to determine whether treatment with sildenafil improves outcomes of patients with persistent pulmonary hypertension (PH) after correction of valvular heart disease (VHD). Methods and results The sildenafil for improving outcomes after valvular correction (SIOVAC) study was a multricentric, randomized, parallel, and placebo-controlled trial that enrolled stable adults with mean pulmonary artery pressure >= 30 mmHg who had undergone a successful valve replacement or repair procedure at least 1 year before inclusion. We assigned 200 patients to receive sildenafil (40 mg three times daily, n = 104) or placebo (n = 96) for 6 months. The primary endpoint was the composite clinical score combining death, hospital admission for heart failure (HF), change in functional class, and patient global self-assessment. Only 27 patients receiving sildenafil improved their composite clinical score, as compared with 44 patients receiving placebo; in contrast 33 patients in the sildenafil group worsened their composite score, as compared with 14 in the placebo group [odds ratio 0.39; 95% confidence interval (Cl) 0.22-0.67; P < 0.001]. The Kaplan-Meier estimates for survival without admission due to HF were 0.76 and 0.86 in the sildenafil and placebo groups, respectively (hazard ratio 2.0, 95% Cl = 1.0-4.0; log-rank P = 0.044). Changes in 6-min walk test distance, natriuretic peptides, and Doppler-derived systolic pulmonary pressure were similar in both groups. Conclusion Treatment with sildenafil in patients with persistent PH after successfully corrected VHD is associated to worse clinical outcomes than placebo. Off-label usage of sildenafil for treating this source of left heart disease PH should be avoided.