Effectiveness and safety of treatment with sildenafil for secondary pulmonary hypertension in heart transplant candidates

Background. Pulmonary hypertension (PH) is a predictor of early death risk owing to right heart insufficiency after orthotopic heart transplantation (OHT). The aim of this study was to evaluate the effectiveness and safety of sildenafil therapy to decrease pulmonary vascular resistance (PVR) in patients with heart failure requiring transplantation, who may otherwise have been excluded because of PH. Material and methods. We analyzed the hemodynamic results of six men (aged 47 to 61) with well-grounded OHT indications and PH diagnosed by a transpulmonary gradient (TPG) > 12 mmHg and/or PVR > 2.5 Wood units. Patients underwent a PH reversibility test with sodium nitroprusside (NPS) to achieve normal TPG and PVR results without a drop in systolic arterial pressure < 85 mmHg. Unresponsiveness to NPS was shown in all subjects, who were subsequently qualified for sildenafil therapy (50 mg bid). Results. After 1 month of sildenafil, three subjects achieved normal TPG and PVR, and acceptable responsiveness of PH to NPS in two other patients, all of whom qualified for OHT. Therapy was unsuccessful in one patient, which was confirmed also by right heart catheterization after 3 months of sildenafil use. Therapy was well tolerated in all patients, namely, no significant drop in arterial pressure on angiotensin-converting enzyme inhibitors. Conclusions. Sildenafil may be effectively used for treatment of secondary, irreversible PH in potential heart transplant recipients.