Effects of L-carnitine on Serum Lactate and Cardiac Complications in Patients With Heart Failure Undergoing Coronary Artery Bypass Grafting: A Randomized Clinical Trial

Background: The effects of L-carnitine on serum lactate and its metabolism remain uncertain, particularly in candidates for revascularization with a high likelihood of a postoperative rise in lactate levels. The present study aimed to assess the effects of L-carnitine on lactate levels after coronary artery bypass graft surgery (CABG) in patients with grade I heart failure. Methods: in this randomized clinical trial, 64 consecutive patients suffering from mild heart failure (grade I) who were candidated for coronary revascularization were randomly divided into 2 groups (32 patients in each group) receiving L-carnitine (3 g orally 2 hours before surgery) or a placebo for the same duration before surgery. Postoperative adverse events, as well as the trend of the change in the levels of serum lactate, creatinine, and hemoglobin, within 24 hours after surgery were assessed. Results: No difference was revealed between the 2 groups in terms of serum lactate levels before surgery (1.51 ± 0.79 in the intervention group vs 1.35 ± 0.43 in the control group; P = 0.33), during intra-aortic balloon pumping (2.27 ± 1.28 in the intervention group vs 2.70 ± 1.42 in the control group; P = 0.20), and also after separating the pump (2.96 ± 1.61 in the intervention group vs 2.56 ± 0.87 in the control group; P = 0.22). No difference was also observed concerning postoperative complications, including atrial fibrillation (P = 0.42), delirium (P = 0.99), agitation (P = 0.88), intra-aortic balloon pump insertion (P = 0.99), atelectasis (P = 0.98), and respiratory distress (P = 0.99). Conclusions: Administrating L-carnitine had no protective effects on the rise in postoperative serum lactate levels following CABG in our patients with low-grade heart failure.