Vascular Health and Risk Management (Apr 2022)
Myocardial Protecting Role of Glutamine in Patients with Low Ejection Fraction Undergoing Elective On-Pump Coronary Artery Bypass Graft Surgery
Abstract
I Made Adi Parmana,1 Cindy Elfira Boom,1 Lisnawati Rachmadi,2 Dudy Arman Hanafy,3 Yunita Widyastuti,4 Muchtaruddin Mansyur,5 Bambang Budi Siswanto6 1Department of Anesthesiology and Intensive Care, National Cardiovascular Center Harapan Kita, Jakarta, Indonesia; 2Department of Anatomical Pathology, Faculty of Medicine, Universitas Indonesia/Dr. Cipto Mangunkusumo Hospital, Jakarta, Indonesia; 3Department of Cardiothoracic and Vascular Surgery, Faculty of Medicine, Universitas Indonesia/National Cardiovascular Center Harapan Kita, Jakarta, Indonesia; 4Department of Anesthesiology and Intensive Care, Universitas Gadjah Mada/Dr. Sardjito Hospital, Yogyakarta, Indonesia; 5Department of Community Medicine, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia; 6Department of Cardiology and Vascular Medicine, Faculty of Medicine, Universitas Indonesia/National Cardiovascular Center Harapan Kita, Jakarta, IndonesiaCorrespondence: I Made Adi Parmana, Department of Anesthesiology and Intensive Care, National Cardiovascular Center Harapan Kita, LetJen S. Parman St No. Kav. 87, West Jakarta, Jakarta, Indonesia, Tel +62 812-4601-212, Email [email protected]: Myocardial injury due to on-pump coronary artery bypass grafting (CABG) in patients with low ejection fraction (EF) is associated with poor outcomes. This study determines whether intravenous glutamine could protect the myocardium during on-pump CABG in patients with low EF.Materials and Methods: This was a double-blind, randomized controlled trial to assess glutamine as a myocardial protector during on-pump CABG in patients with left ventricle EF of 31– 50%, conducted from January to October 2021. Patients in the glutamine group (n = 30) received 0.5 g/kg of 20% glutamine solution diluted with 0.9% NaCl up to 500 mL in total volume over a period of 24 hours. Patients in the control group (n = 30) received 0.9% NaCl over the same period. The primary outcomes were plasma troponin I and plasma glutamine levels. Secondary outcomes included α-ketoglutarate (α-KG) levels and histopathology scoring of the right atrial appendage tissue, plasma lactate levels, hemodynamic measurement, and morbidity.Results: Twenty-nine patients from each group (58 in total) were included in the analysis. Plasma troponin I levels at 6 and 24 hours after cardiopulmonary bypass (CPB) were significantly lower in the glutamine than the control group (mean 3.43 ± 1.51 ng/mL vs mean 4.41 ± 1.89 ng/mL; p = 0.034; median 3.08 ng/mL [min–max: 1.30– 6.59] vs median 3.77 ng/mL [min–max: 0.00– 36.53]; p = 0.038, respectively). Plasma glutamine levels at 24 hours after CPB were significantly higher in the glutamine than the control group (mean 935.42 ± 319.10 μmol/L vs mean 634.79 ± 243.89 μmol/L, p = 0.001). Plasma lactate levels at 6 and 24 hours after CPB were significantly lower in the glutamine than the control group (median 5.30 mmol/L [min-max: 1.20– 9.50] vs median 5.70 mmol/L [min-max: 2.80– 11.30], p = 0.042; mean 2.08 ± 0.67 mmol/L vs mean 2.46 ± 0.69 mmol/L, p = 0.044, respectively). Myocardial injury score was significantly lower in the glutamine than the control group (mean 1.30 ± 0.24 vs mean 1.48 ± 0.26, p = 0.011).Conclusion: Perioperative administration of 0.5 g/kg intravenous glutamine solution over the period of 24 hours has myocardial protection effect in patients with low EF who undergo elective on-pump CABG.Keywords: glutamine, myocardial protection, coronary artery bypass grafting, cardiopulmonary bypass, low ejection fraction, myocardial injury
