Vol:.(1234567890) Heart Vessels (2017) 32:1488–1497 DOI 10.1007/s00380-017-1023-2 1 3 ORIGINAL ARTICLE A retrospective comparison of inhaled milrinone and iloprost in post‑bypass pulmonary hypertension Kassiani Theodoraki 1,5  · Apostolos Thanopoulos 2  · Panagiota Rellia 2  · Evangelos Leontiadis 3  · Dimitrios Zarkalis 4  · Konstantinos Perreas 4  · Theophani Antoniou 2   Received: 27 February 2017 / Accepted: 14 July 2017 / Published online: 17 July 2017 © Springer Japan KK 2017 Both agents were devoid of systemic side efects, since mean arterial pressure and systemic vascular resistance were not afected. A decrease in intrapulmonary shunt by inhalation of both agents was also demonstrated. Pulmonary vasodila- tation attributed to iloprost seems to be of greater magnitude and of longer duration as compared to that of inhaled mil- rinone. Both substances proved to be selective pulmonary vasodilators. The greater magnitude and of longer duration vasodilatation attributed to iloprost may be due to its longer duration of action. Keywords Pulmonary vascular resistance · Pulmonary hypertension · Inhaled vasodilators · Cardiopulmonary bypass Introduction Pulmonary hypertension (PH) can occur after cardiac sur- gery and is mainly associated with the pulmonary endothe- lial infammatory response to extracorporeal circulation [1]. Therefore, weaning from cardiopulmonary bypass (CPB) may prove particularly challenging as a result of superim- posed acute right ventricular dysfunction in the setting of the elevated pulmonary vascular resistance (PVR). The risk is particularly high in patients undergoing heart valve surgery. In this patient population, preexisting PH can be further exacerbated by the endothelial dysfunction induced by CPB, thus increasing patients’ morbidity and mortality [2, 3]. In this context, several pharmacologic agents have been used to reduce the occurrence of PH post-CPB [4]. Intra- venous vasodilators (such as nitrates or prostaglandins) attenuate PH, but associated systemic hypotension with escalating dosage due to lack of pulmonary selectivity is the limiting factor [5]. Furthermore, hypoxemia may occur Abstract During cardiac operations, weaning from car- diopulmonary bypass (CPB) may prove challenging as a result of superimposed acute right ventricular dysfunction in the setting of elevated pulmonary vascular resistance (PVR). The aim of this study was to retrospectively evalu- ate the efect of inhaled milrinone versus inhaled iloprost in patients with persistent pulmonary hypertension follow- ing discontinuation of CPB. Eighteen patients with elevated PVR post-bypass were administered inhaled milrinone at a cumulative dose of 50 μg kg −1 . These patients were ret- rospectively matched with 18 patients who were adminis- tered 20 μg of inhaled iloprost. Both drugs were adminis- tered through a disposable aerosol-generating jet nebulizer device and inhaled for a 15-min period. Hemodynamic measurements were performed before and after cessation of the inhalation period. Both inhaled milrinone and inhaled iloprost induced signifcant reductions in mean pulmonary artery pressure and PVR and signifcant increases in cardiac index in patients with post-CPB pulmonary hypertension. The favorable efect of both agents on the pulmonary vascu- lature was confrmed by echocardiographic measurements. * Kassiani Theodoraki ktheodoraki@hotmail.com 1 Department of Anesthesiology, Aretaieion University Hospital, Vassilissis Sofas 76, 11528 Athens, Greece 2 Department of Anesthesiology, Onassis Cardiac Surgery Center, Athens, Greece 3 Department of Cardiology, Onassis Cardiac Surgery Center, Athens, Greece 4 Department of Cardiac Surgery, Onassis Cardiac Surgery Center, Athens, Greece 5 National and Kapodistrian University of Athens, Athens, Greece