Objective This study was conducted to determine whether the administration of intralipid just before aortic cross-unclamping would reduce myocardial injury in patients undergoing valve replacement surgery.

Methods Seventy-three adult patients, scheduled for elective aortic or mitral valve surgery without significant coronary stenosis (>70%), were randomly assigned to the intralipid postconditioning (ILPC) group (n=37) or control group (n=36): the ILPC group received an intravenous infusion of 20% intralipid (2 mL/kg) just 10 min before aortic cross-unclamping, and the control group received an equivalent volume of normal saline. Serum cardiac troponin T (cTnT) and creatine kinase-MB (CK-MB) was measured before surgery and at 4, 12, 24, 48 and 72 hours after surgery. The primary end points were the 72-hour area under the curve (AUC) for cTnT and CK-MB.

Results No significant difference between the ILPC and control arm was observed, including the age, sex or number of aortic versus mitral valves or left ventricular ejection fraction at baseline. The total 72-hour AUC of cTnT and CK-MB in patients assigned to ILPC were significantly reduced by 32.3% (p=0.004) and 26.4% (p=0.0185) compared with control, respectively. None of the treated patients had abnormal blood lipid metabolism, abnormal renal or hepatic function or significant related complications.

Conclusion The protective effect of postischaemic administration of intralipid prior to aortic cross-unclamping on reperfusion injury was found when determined by biomarkers of myocardial injury but not by cardiac function or other clinical outcomes in patients undergoing valve replacement surgery. Hence, clinical benefits of this protection need larger clinical trials to confirm.

Trial registration number ClinicalTrials.gov ID: ChiCTR-IOR-14005318.