Effect of oral sildenafil citrate on intraoperative hemodynamics in patients with pulmonary hypertension undergoing valvular heart surgery.

Abstract

Pulmonary hypertension remains a major problem during the perioperative period for surgical correction of long-standing valvular heart disease. Sildenafil citrate (INN sildenafil) is a selective phosphodiesterase type 5 inhibitor that is being increasingly recognized as a treatment modality for pulmonary hypertension. There is lack of evidence, however, regarding its pulmonary vasodilatory effect in anesthetized cardiac surgical patients. We therefore evaluated the effects of sildenafil on hemodynamics in patients with concomitant pulmonary hypertension undergoing valvular heart surgery in a controlled, prospective, randomized, double-blind trial. Fifty-three patients scheduled for valvular heart surgery with mean pulmonary arterial pressure greater than 30 mm Hg were randomly treated with either 50 mg oral sildenafil (n = 26) or placebo (n = 27) 10 minutes before induction of anesthesia. Hemodynamic variables were measured 5 minutes after induction of anesthesia (baseline) and at 30 and 60 minutes after medication. Patient characteristics and baseline hemodynamics were similar between groups. Systolic and mean pulmonary arterial pressures and pulmonary vascular resistance were significantly lower in the sildenafil group at 30 minutes after medication, without any changes in mean systemic arterial pressure and systemic vascular resistance. Sildenafil produced significant pulmonary vasodilatory effect relative to placebo in anesthetized cardiac surgical patients with pulmonary hypertension. With respect to the predominant selectivity of sildenafil to pulmonary vasculature shown in this study and other potentially beneficial effects such as myocardial protection, use of sildenafil in the intraoperative period in cardiac surgical patients with pulmonary hypertension should be considered.