title: Myocardial Protective Effects of L-Carnitine on Ischemia-Reperfusion Injury in Patients With Rheumatic Valvular Heart Disease Undergoing Cardiac Surgery.
abstract: OBJECTIVE
  The authors used L-carnitine as an ingredient in cardioplegic solution during valve replacement surgery to investigate the protective effect of L-carnitine on myocardial ischemia-reperfusion injury (MIRI) and its possible mechanism.
  
  
  METHODS
  Prospective, randomized study.
  
  
  METHODS
  A tertiary-care hospital.
  
  
  METHODS
  The study comprised 90 patients undergoing valve replacement under cardiopulmonary bypass.
  
  
  METHODS
  Patients were divided randomly into 3 groups. L-carnitine was added to the crystalloid cardioplegic solution for experimental group 1 (3 g/L) and experimental group 2 (6 g/L), whereas no L-carnitine was used in the control group. The remainder of the treatment was identical for all 3 groups.
  
  
  RESULTS
  Serum was collected from each patient 1 hour before the surgery and at 2, 6, 24, and 72 hours after unclamping the aorta, and tissue samples were obtained before cardiac arrest and after unclamping the aorta. The postoperative levels of serum aspartate aminotransferase, creatine kinase, creatine kinase-MB isozyme, and lactic acid dehydrogenase and the apoptotic index were all lower in the 2 experimental groups than those in the control group. In addition, each of the aforementioned serum enzyme levels and the apoptotic index in all 3 groups significantly increased after unclamping the aorta compared with baseline levels taken before surgery. Bcl-2 expression was higher and Bax was lower in the 2 experimental groups compared with those of the control group after unclamping the aorta. However, there was no significant difference in all the postoperative indices between the 2 experimental groups.
  
  
  CONCLUSIONS
  L-carnitine may reduce cardiopulmonary bypass-induced myocardial apoptosis through modulating the expressions of Bcl-2 and Bax, resulting in a protective effect from MIRI.
authors: Department of *Cardiovascular Surgery, The First Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an Shaanxi, China.
authors: Ming
authors: M
authors: Li
authors: †Department of Laboratory, The Second Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an Shaanxi, China.
authors: Li
authors: L
authors: Xue
authors: ‡Tumour Hospital of Shaanxi Province, Xi'an Shaanxi, China.
authors: Haifeng
authors: H
authors: Sun
authors: Department of *Cardiovascular Surgery, The First Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an Shaanxi, China. Electronic address: xusuochuna@sina.com.
authors: Suochun
authors: S
authors: Xu
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000187:drug effects; D015415:Biomarkers / Q000097:blood; D002314:Cardioplegic Solutions; D002315:Cardiopulmonary Bypass / Q000009:adverse effects; D002331:Carnitine / Q000627:therapeutic use*; D005260:Female; D006324:Heart Arrest, Induced / Q000379:methods; D006349:Heart Valve Diseases / Q000601:surgery*; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015428:Myocardial Reperfusion Injury / Q000209:etiology / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D009206:Myocardium / Q000378:metabolism; D011446:Prospective Studies; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D012214:Rheumatic Heart Disease / Q000601:surgery*; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D015415:Biomarkers; D002314:Cardioplegic Solutions; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; D002331:Carnitine
keywords: L-carnitine; apoptosis; cardioplegia; myocardial protection; rheumatic valvular heart disease