Inhaled and Intravenous Milrinone in Patients With Severe Pulmonary Hypertension

Inclusion Criteria: * Patients scheduled to undergo mitral valve surgery by cardiopulmonary bypass with estimated mean pulmonary artery pressure =\>55 estimated by using preoperative Doppler echocardiography Exclusion Criteria: Patients were excluded if they had surgery without CPB, preoperative hemodynamic instability (defined as acute requirement for vasoactive support or mechanical device),Patients with severe LV dysfunction (LV ejection fraction of less than 30% congenital heart disease, a contraindication to transesophageal echocardiography (TEE), emergency surgery or re-do surgeries severe renal or hepatic disease , coagulopathy, and thromboembolic disease treated with anticoagulants