Inhaled Iloprost Versus Epoprostenol in Heart Transplant Recipients

Acute right ventricular dysfunction is a challenging problem in the immediate postoperative period following orthotopic heart transplantation. There are no prior reports of the use of inhaled iloprost in the setting of acute right ventricular dysfunction and acute pulmonary hypertension. Our hypothesis was that the use of inhaled iloprost in heart transplant recipients would be associated with a reduction in the duration of mechanical ventilation compared to patients being treated with continuous inhaled epoprostenol. Additionally, we hypothesized that the change in inhaled vasodilatory therapy would not be associated with a significant change in postoperative bleeding or use of vasoactive medications.

We reviewed charts of 80 consecutive patients undergoing heart transplantation at our institution between July 1, 2003, and August 8, 2008. From July 1, 2003 to March 13, 2006, epoprostenol was our primary vasodilator; subsequently epoprostenol was replaced with iloprost. We included 39 subjects who received epoprostenol and 40 subjects who received iloprost. Data were collected on the use of inhaled vasodilators, comparing periods before and after our institutional protocol change. Demographic data, hemodynamic values, drain output, and any requirement for vasoactive medication infusions were collected. Our primary end point was the natural logarithm of duration of mechanical ventilation. Secondary end points were hemodynamic values and length of ICU and hospital stay.

Subjects treated with iloprost were mechanically ventilated for 0.36 ± 0.20 (adjusted mean ± SE) log days, which was shorter (P = .033) than the 1.00 ± 0.22 logdays for subjects treated with epoprostenol. This resulted in an estimated median number of mechanically ventilated days for subjects treated with epoprostenol that was approximately 1.9 times longer than the estimated median number of ventilated days for subjects treated with iloprost (95% CI 1.05-3.4, P = .033). There were no differences in safety end points or length of hospital stay.

Use of inhaled iloprost was associated with shorter duration of mechanical ventilation compared to inhaled epoprostenol, without safety concerns.