Purpose: Significant pulmonary hypertension is a predictor of postoperative right heart insufficiency and increased mortality in patients undergoing orthotopic heart transplantation. Since the use of iv vasodilators is limited by their systemic effects, we evaluated the pulmonary and systemic hemodynamic effects of inhaled aerosolized iloprost (IP) in heart transplant candidates with elevated pulmonary vascular resistance (PVR).
Methods: Twenty-nine male heart transplant candidates because of dilated or ischemic cardiomyopathy with elevated PVR were included in the study. After assessing baseline hemodynamics, 50 micro g aerosolized IP were administered by inhalation.
Results: Inhalation of iloprost reduced PVR index (PVRI; 416 +/- 180 vs 349 +/- 173 dyn x sec(-1) x m(-2) x cm(-5); P < 0.01) and mean pulmonary artery pressure (MPAP; 28.6 +/- 9 vs 24.2 +/- 9.1 mmHg; P < 0.01), but did not affect blood pressure or systemic vascular resistance. An additional improvement of ventricular performance with an increase of cardiac index (CI; 2.8 +/- 0.7 vs 2.6 +/- 0.7 L x min(-1) x m(-2); P < 0.05) and a decrease of pulmonary capillary wedge pressure (PCWP; 15.6 +/- 6.8 vs 12.8 +/- 7.1 mmHg; P < 0.01) was observed after inhalation of IP.
Conclusions: Inhaled aerosolized iloprost effectively reduces MPAP and is accompanied by an increase in CI and stroke index. Further advantages of iloprost inhalation are the lack of adverse reactions and ease of administration. Iloprost may be a useful drug to screen for vascular reactivity in cardiac transplantation patients.