Off-Pump Coronary Bypass Grafting Is Associated with Less Myocardial Injury Than Coronary Bypass Surgery with Cardiopulmonary Bypass
DOI:
https://doi.org/10.1532/hsf.759Abstract
Background: Excessive myocardial necrosis following coronary artery bypass grafting is associated with adverse outcome. The present study was designed to assess the extent of myocardial injury after conventional coronary artery bypass grafting with cardiopulmonary bypass (ONCAB) compared with off-pump coronary artery bypass (OPCAB).
Methods: Measurements of serum cardiac troponin T (TnT) were obtained in 137 consecutive, unselected patients who underwent coronary artery bypass grafting. Serial blood sampling was performed at 3 time intervals after surgery: immediately postoperatively, 6 to 12 hours postoperatively, and 18 to 24 hours postoperatively.
Results: ONCAB patients totaled 122, and OPCAB patients numbered 15. Ten patients in the ONCAB group suffered perioperative complications, compared with no patients in the OPCAB group. At each time point examined, OPCAB patients exhibited significantly less release of TnT than ONCAB patients (immediately postoperative TnT, 1.99 ± 4.75 ng/mL versus 0.20 ± 0 .32 ng/mL, P = .004; 6- to 12-hour TnT, 2.28 ± 3.66 ng/mL versus 0.37 ± 0.32 ng/mL, P = .001; and 18- to 24-hour TnT 1.59 ± 3.49 ng/mL versus 0.30 ± 0.32 ng/mL, P = .01). When ONCAB patients with perioperative ischemic complications were excluded, the differences between the 2 groups remained. The OPCAB patients still demonstrated less TnT release, typically 5- to 6-fold less than for ONCAB patients.
Conclusions: The nearly 6-fold reduction of postoperative TnT associated with OPCAB suggests that off-pump surgery may offer superior cardioprotection than coronary artery bypass grafting with conventional cardiopulmonary bypass.
References
Svennevig J. 2000. Off-pump vs on-pump surgery: a review. Scand Cardiovasc J 34:7-11.nvan Dijk D, Nierich AP, Jansen EW, et al. 2001. Early outcome after off-pump versus on-pump coronary bypass surgery. Circulation 104:1761-6.nWan S, Izzat MB, Lee TW, Wan IYP, Tang NLS, Yim APC. 1999. Avoiding cardiopulmonary bypass in multivessel CABG reduces cytokine response and myocardial injury. Ann Thorac Surg 68:52-7.nYacoub M. 2001. Off-pump coronary bypass surgery: in search of an identity. Circulation 104:1743-5.nYokoyama T, Baumgartner FJ, Gheissari A, Capouya ER, Panagiotides GP, Declusin RJ. 2000. Off-pump versus on-pump coronary bypass in high-risk subgroups. Ann Thorac Surg 70:1546-50.nAscione R, Lloyd CT, Gomes WJ, Caputo M, Bryan AJ, Angelini GD. 1999. Beating versus arrested heart revascularization: evaluation of myocardial function in a prospective randomized study. Eur J Cardiothorac Surg 15:685-90.nAscione R, Lloyd CT, Underwood MJ, Gomes WJ, Angelini GD. 1999. On-pump versus off-pump coronary revascularization: evaluation ofnrenal function. Ann Thorac Surg 68:493-8.nBoncheck LI, Ullyot DJ. 1998. Minimally invasive coronary bypass: a dissenting opinion. Circulation 98:495-7.nBredee JJ, Jansen EWL. 1998. Coronary artery bypass grafting withoutcardiopulmonary bypass. Curr Opin Cardiol 13:476-82.nDiegeler A, Hirsch R, Schneider F, et al. 2000. Neuromonitoring and neurocognitive outcome in off-pump versus conventional coronary bypass operation. Ann Thorac Surg 69:1162-6.nFavaloro R. 1998. Critical analysis of coronary artery bypass graft surgery: a 30-year journey. J Am Coll Cardiol 31:1B-63B.nJanuzzi JL, Lewandrowski K, MacGillivray TE, et al. 2002. A comparison of cardiac troponin T and creatine kinase-MB for patient evaluation after cardiac surgery. J Am Coll Cardiol 39:1518-23.nJegaden O, Mikacloff P. 2001. Off-pump coronary artery bypass surgery: the beginning of the end? Eur J Cardiothoracic Surg 19:237-8.nKilger E, Pichler B, Weis F, et al. 2000. Markers of myocardial ischemia after minimally invasive and conventional coronary operation. Ann Thorac Surg 70:2023-8.nKlatte K, Chaitman BR, Theroux P, et al. 2001. Increased mortality after coronary artery bypass graft surgery is associated with increased levels of postoperative creatine kinase-myocardial band isoenzyme release. J Am Coll Cardiol 38:1070-7.nKrejca M, Skiba J, Szmagala P, Gburek T, Bochenek A. 1999. Cardiac troponin T release during coronary surgery using intermittent cross-clamp with fibrillation, on-pump, and off-pump beating heart. Eur J Cardiothorac Surg 16:337-41.n
