title: Effects of ischemic preconditioning in human heart.
abstract: BACKGROUND
  The aim of this study is to investigate the effects of ischemic preconditioning (IP) on myocardium and the level of nitric oxide (NO) in patients undergoing aorta-coronary bypass surgery.
  
  
  METHODS
  Twenty consecutive patients with coronary artery disease were subjected into two equal groups; the IP group and the control group. Following the onset of cardiopulmonary bypass in the study group, hearts were preconditioned with two 3-minute periods of cross-clamping separated by 2 minutes of reperfusion. In the control group, cardiopulmonary bypass was continued for 10 minutes without using cross-clamp. Arterial and coronary sinus blood samples were used to determine serum NO, malondialdehyde (MDA), creatine phosphokinase-MB (CKMB), and lactate dehydrogenase (LDH) levels. Need for defibrillation after cross-clamp removal, ECG changes, postoperative arrhythmias, ejection fraction, and fractional shortening rates were recorded as hemodynamic data.
  
  
  RESULTS
  Serum NO level was higher in the study group 5 minutes after aortic clamp removal (199.3 +/- 92.7 vs. 112.2 +/- 35.8 micromol; p = 001). Serum MDA (2.55 +/- 0.4 vs. 4.06 +/- 0.5; etamol/ml; 5 minutes after the aortic clamp removal; p = 0.0002); CK-MB (22.8 +/- 2.5 vs. 37.4 +/- 4.1; U/L 12 hours after the operation, p < 0.0001), and LDH (501.8 +/- 46.7 vs. 611.4 +/- 128.3; IU/L 48 hours after the operation, p = 0.02) levels were significantly lower in the preconditioned group when compared with the control group. Also, need for electrical defibrillation was significantly lower in the study group; Ejection fraction (64.3 +/- 6.3 vs. 57.6 +/- 7.6; p = 0.04) and fractional shortening (31.7 +/- 3.9 vs. 26.2 +/- 4.0; p = 0.04) rates were better in the study group postoperatively.
  
  
  CONCLUSIONS
  These data may suggest that cardioprotection by ischemic preconditioning offers higher NO production, a lower myocardial ischemia, and better functional recovery of the hearts in coronary artery surgery patients.
authors.affiliation: Department of Cardiovascular Surgery, Gazi University Faculty of Medicine, Ankara, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Buyukates
authors.forename: Sedat
authors.initials: S
authors.lastname: Kalaycioglu
authors.forename: Eser
authors.initials: E
authors.lastname: Oz
authors.forename: Halim
authors.initials: H
authors.lastname: Soncul
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood*; D016022:Case-Control Studies; D001026:Coronary Artery Bypass / Q000379:methods* / Q000401:mortality; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery*; D003402:Creatine Kinase / Q000097:blood; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006439:Hemodynamics / Q000502:physiology*; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D019194:Ischemic Preconditioning / Q000379:methods*; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D009569:Nitric Oxide / Q000097:blood; D011183:Postoperative Complications / Q000401:mortality; D011300:Preoperative Care / Q000379:methods; D011336:Probability; D011446:Prospective Studies; D011859:Radiography; D012016:Reference Values; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D009569:Nitric Oxide; D008315:Malondialdehyde; D003402:Creatine Kinase