Abstract

BACKGROUND: Sildenafil, a phosphodiesterase-5 inhibitor, has been shown to decrease pulmonary vascular resistance (PVR) in patients with heart failure. The purpose of the study was to evaluate the effect of sildenafil on clinical status and pulmonary vascular reactivity in patients with congestive heart failure.

MATERIAL AND METHODS: We enrolled 20 patients (18 men and 2 women, mean age 51±12 years, diagnosed with congestive heart failure and pulmonary hypertension. This was a prospective, single-center study. Patients were treated with sildenafil 25 mg TDS for 12 months. Protocol included NYHA evaluation and repeated echocardiography, cardiac pulmonary stress tests, and right- sided catheterization.

RESULTS: Initially, there were 16 (80%) patients in III NYHA status and 4 (20%) patients in II NYHA. After 12 months, 8 patients were in NYHA III (40%) status and 12 patients in NYHA II (60%). Peak oxygen consumption increased from 12±3 ml/kg/min to 19±4 ml/kg/min after 1-year therapy (p<0.001). The cardiac index increased from 3.1±0.6 L/min/m2 to 3.6±0.4 L/min/m2 (p<0.05). Pulmonary vasculature resistance decreased after 1-year therapy (4.7±1 vs. 1.6±0.5 Woods units (p<0.005) comparing to initials. Mean pulmonary artery pressure decreased to 23±6 mmHg from 42±5 mmHg (p<0.001) after 1-year therapy.

CONCLUSIONS: One-year sildenafil therapy effectively improved clinical status and pulmonary vascular resistance in patients diagnosed with congestive heart failure.

Keywords: cardiac catheterization, Heart Failure, Phosphodiesterase 5 Inhibitors, Vascular Resistance