Official Publication of the National Center for Trauma Research Trauma Monthly 2251-7464 31 4 2026 07 01 Effect of Intraoperative Milrinone on Left Ventricular Diastolic Function in Critically Ill Patients Undergoing CABG: A Transesophageal Echocardiography Study 1922 1934 253279 10.30491/tm.2026.590406.1956 EN Tayebeh Sohrabirad Trauma Research Center, Clinical Sciences Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran Seyed Mohammad Saeid Ghiasi Cardiovascular Research Center, Clinical Research Institute, School of Medicine, Baqiyatullah University of Medical Sciences, Tehran, Iran 0000-0001-8637-4561 Marziyeh Lak Trauma Research Center, Clinical Sciences Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran Maryam Moshkani Farahani Cardiovascular Research Center, Clinical Research Institute, School of Medicine, Baqiyatullah University of Medical Sciences, Tehran, Iran Journal Article 2026 07 07 <strong>Introduction: </strong>This study evaluated whether intraoperative milrinone improves cardiac diastolic and systolic function in patients undergoing elective on-pump CABG.<br><strong>Method: </strong>In this prospective study, 30 patients undergoing elective on-pump CABG were allocated equally to a milrinone group (n=15) or a control group (n=15). After anesthesia induction and before CPB, the milrinone group received a loading dose of 50 µg/kg over 10 minutes, followed by an infusion of 0.5 µg/kg/min continued for 6 hours postoperatively; the control group received an identical volume of normal saline. TEE was performed at two time points: after induction (baseline) and after separation from CPB. Baseline diastolic function was characterized using standard Doppler indices; however, patients were not preselected or stratified by diastolic dysfunction grade, which represents a limitation of the study design. Echocardiographic indices (fractional area change [FAC], pulmonary venous flow velocity [PV], deceleration time [DT], E/PV, A-wave duration [Adur], atrial reversal duration [ARdur]), hemodynamic variables, vasoactive requirements, and intensive care unit (ICU) length of stay were compared between groups.<br><strong>Result: </strong>Baseline characteristics, including age, sex, weight, height, comorbidities, left ventricular ejection fraction (p=0.10), surgical duration (p=0.18), and CPB duration (p=0.10) were comparable between groups. Milrinone significantly increased FAC after CPB relative to control (55.39±10.86% vs 45.71±12.04%; p=0.028) and relative to its own baseline (vs 42.77±11.27%; p<0.001). Pulmonary venous flow velocity after CPB was significantly higher in the milrinone group than in controls (96.95±31.08 vs 76.03±22.54 cm/s; p=0.049) and higher than its own baseline (vs 63.59±20.72 cm/s; p<0.001). No significant between-group differences were observed in DT, E/PV, Adur, or ARdur. Hemodynamic parameters, norepinephrine requirement during CPB (p=0.92), inotrope and nitroglycerin dosing, cardiac rhythm, and ICU length of stay did not differ significantly between groups<br><strong>Conclusion<span dir="RTL" lang="FA">: </span></strong> Intraoperative milrinone significantly improved systolic performance (FAC) and pulmonary venous flow in patients undergoing elective on-pump CABG, with a relative improvement in selected diastolic indices and no adverse hemodynamic effects. However, because patients were not preselected for baseline diastolic dysfunction, the study was underpowered to detect a dedicated diastolic benefit. These findings suggest a potential role for milrinone in the perioperative management of CABG patients, particularly those with preexisting diastolic dysfunction. Adequately powered multicenter trials are warranted to confirm a dedicated diastolic benefit and to evaluate its impact on clinical outcomes, particularly in higher-risk or critically ill subpopulations. https://www.traumamon.com/article_253279_c287c0ee231609fc9cca73721b45d1f0.pdf