HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): John D. Puskas Robert A. Guyton Jakob Vinten-Johansen Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Muraki, S. Articles by Vinten-Johansen, J. Search for Related Content PubMed PubMed Citation Articles by Muraki, S. Articles by Vinten-Johansen, J. Related Collections Coronary disease Myocardial protection

J Thorac Cardiovasc Surg 2002;123:53-62
© 2002 The American Association for Thoracic Surgery

Cardiopulmonary Support and Physiology

Preserved myocardial blood flow and oxygen supply-demand balance with active coronary perfusion during simulated off-pump coronary artery bypass grafting

From the Section of Cardiothoracic Surgery, Carlyle Fraser Heart Center, Emory University School of Medicine, Atlanta, Ga.

Supported by the Carlyle Fraser Heart Center of Crawford Long Hospital, Emory University, and a Scientific Development Award (Z-QZ) and a Grant-in-Aid (JV-J) from the National American Heart Association.

Received for publication Dec 20, 2000. Revisions requested April 17, 2001; revisions received May 14, 2001. Accepted for publication June 15, 2001. Address for reprints: Jakob Vinten-Johansen, PhD, Cardiothoracic Research Laboratory, Carlyle Fraser Heart Center, 550 Peachtree Street NE, Atlanta, GA 30308-2225 (E-mail: jvinten{at}emory.edu).

Background: During off-pump coronary artery bypass surgery, concern remains about the possible myocardial injury associated with the transient occlusion and stabilization of the target vessels. Although intraluminal shunts are used to avoid ischemia during graft anastomosis, blood flow through the shunts can be affected by upstream pressure and inherent resistance, resulting in reduced blood flow during hypotension or severe proximal stenosis.
Methods: In anesthetized dogs regional myocardial blood flow (microspheres), oxygen consumption, lactate extraction, and systolic shortening (sonomicrometry) were measured in the myocardium served by the left anterior descending coronary artery with native perfusion after interposition of a 2.25-mm shunt (90% of left anterior descending diameter) and during active coronary perfusion with a constant flow pump. Measurements were made under normotension and hypotension produced by partial caval occlusion to reduce arterial pressure by 50%.
Results: Interposition of the shunt reduced blood flow by 67.8%, regional oxygen delivery by 59.8%, and systolic shortening by 45.6% relative to baseline, but lactate extraction (31.0% vs 31.2%) and oxygen supply-consumption (O₂S/myocardial oxygen consumption ratio, 2.7 ± 0.5 vs 2.6 ± 0.5) were comparable with baseline values. Hypotension further decreased these physiologic values and was associated with local lactate production (–67.4% extraction) and decreased O₂S/myocardial oxygen consumption ratio (1.3 ± 0.1). Active coronary perfusion was associated with regional blood flow, oxygen delivery, systolic shortening, and lactate extraction comparable with baseline values. In contrast to the shunt, active perfusion maintained myocardial flow, oxygen delivery, and lactate extraction during hypotension and normalized the O₂S/myocardial oxygen consumption ratio, although systolic shortening decreased as a result of ventricular unloading.
Conclusion: Intraluminal shunts may impede oxygen delivery to the target myocardium, which precipitates regional ischemia during transient hypotension. Active coronary perfusion provides adequate oxygen supply independent of systemic blood pressure.

This article has been cited by other articles:

				M. Boodhwani, J. Feng, S. Mieno, B. Ramlawi, N. Sodha, R. Clements, and F. W. Sellke Effects of purified poloxamer 407 gel on vascular occlusion and the coronary endothelium. Eur. J. Cardiothorac. Surg., May 1, 2006; 29(5): 736 - 741. [Abstract] [Full Text] [PDF]

				Y. Koshida, G. Watanabe, T. Yasuda, S. Tomita, S. Kadoya, and T. Kanamori Portable Coronary Active Perfusion System for Off-Pump Coronary Artery Bypass Grafting Ann. Thorac. Surg., February 1, 2006; 81(2): 706 - 710. [Abstract] [Full Text] [PDF]

				M. Boodhwani, W. E. Cohn, J. Feng, B. Ramlawi, S. Mieno, A. Schwarz, and F. W. Sellke Safety and Efficacy of a Novel Gel for Vascular Occlusion in Off-Pump Surgery Ann. Thorac. Surg., December 1, 2005; 80(6): 2333 - 2337. [Abstract] [Full Text] [PDF]

				H. Kamiya, G. Watanabe, T. Kanamori, N. Ishikawa, T. Terada, and K. Kawakami Instant myocardial blood flow monitor: its calibration and assessment of flow capacity of the intracoronary shunt tube Ann. Thorac. Surg., July 1, 2004; 78(1): 167 - 172. [Abstract] [Full Text] [PDF]

				S. Muraki, M. Tsukamoto, K. Komatsu, J. Sakata, S. Ohori, T. Hasegawa, and T. Abe Minimally ischemic off-pump coronary artery bypass grafting: active perfusion-assist with nitroglycerin-supplemented blood Ann. Thorac. Surg., July 1, 2003; 76(1): 298 - 300. [Abstract] [Full Text] [PDF]

				H. Kamiya, G. Watanabe, and T. Kanamori Flow simulation of the intracoronary shunt tube for off-pump coronary artery bypass Eur. J. Cardiothorac. Surg., May 1, 2003; 23(5): 665 - 669. [Abstract] [Full Text] [PDF]

				W. A. Cooper, J. S. Corvera, V. H. Thourani, J. D. Puskas, J. M. Craver, O. M. Lattouf, and R. A. Guyton Perfusion-assisted direct coronary artery bypass provides early reperfusion of ischemic myocardium and facilitates complete revascularization Ann. Thorac. Surg., April 1, 2003; 75(4): 1132 - 1139. [Abstract] [Full Text] [PDF]