Inhaled milrinone for pulmonary hypertension in high-risk cardiac surgery: silver bullet or just part of a broader management strategy?

Excerpt

Pulmonary hypertension (PH) and right ventricular (RV) dysfunction are common and potentially devastating conditions in patients undergoing cardiac surgery. The prevalence of PH and elevated pulmonary vascular resistance (PVR) in patients with aortic stenosis and regurgitation is 15-30% and ≥ 25%, respectively, and at least 40% in patients with mitral stenosis.1 In certain patients with pulmonary venous hypertension due to valvular cardiac disease, the elevated PVR persists or is slow to regress after valve replacement/repair as a result of remodelling of the pulmonary circulation.2 Preoperative PH is associated with prolonged mechanical ventilation, greater duration of hospital stay, and increased operative and long-term mortality.3 This is likely a consequence of the relationship between PH and the development of perioperative RV failure, a condition that, even with early recognition and treatment, has high morbidity and greater than 30% mortality.4,5 Despite the critical importance of perioperative PH and RV dysfunction, there is a paucity of high-quality clinical trials addressing the perioperative management of these conditions. …