PURPOSE:Some patients with advanced heart failure develop severe pulmonary hypertension (PH). Impaired reactivity of pulmonary bed to vasodilator challenge with PGE1 or with other vasodilators significantly predicts poor heart transplant (Tx) outcome. Testing of PH reversibility is therefore used for selection of Tx candidates. The aim of our study was to compare the effects of PGE1, an agent mostly used at our institution, with novel potent pulmonary vasodilator - sildenafil citrate on hemodynamics in patients with chronic heart failure and severe PH.
METHODS:In period 1–12/2007 we performed 263 right heart catheterizations (RHC) as a part of pre-Tx work-up. In 17 patients (6%), pulmonary hemodynamics mandated testing of reversibility (TPG>15 mmHg or PVR>3 w.u. in euvolemia). RHC was performed using thermodilution SG catheter, systemic blood pressure was monitored invasively from radial artery. Hemodynamic parameters were measured at the baseline, after 5 min of continuous infusion of PGE1 (Alprostan, Leciva, 200 ug/kg/min), and 1h after single oral dose of sildenafil 40 mg (Revatio, Pfizer). Drug-induced changes from baseline were compared with paired t statistics.
RESULTS:Group included 15 men and 2 women (51±11 years) with CHF due to coronary disease (n=11, 65%) or dilated cardiomyopathy (n=6, 35%). Results are summarized in the Table. Both drugs reduced transpulmonary gradient, pulmonary and systemic resistance and increased cardiac output. The effect of sildenafil on PVR and pulmonary selectivity ratio (TSR/PVR) was significantly higher than the effects of PGE1.
CONCLUSION:Sildenafil had superior ability to unmask reversible pulmonary hypertension secondary to advanced heart failure than PGE1. Vasodilatatory effects of sildenafil are more pronounced in pulmonary than in systemic circulation.
CLINICAL IMPLICATIONS:Hemodynamic testing using sildenafil is viable alternative to PGE1.
DISCLOSURE:Hikmet Al-Hiti, No Financial Disclosure Information; No Product/Research Disclosure Information