| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ann Thorac Surg 2002;73:842
© 2002 The Society of Thoracic Surgeons
a Division of Thoracic and Cardiac Surgery, University of Massachusetts Medical Center, 55 Lake Ave, N Room #53-751, Worcester, MA 01655-0304, USA
e-mail: vanderst{at}ummhc.org
Should cardioplegia solutions contain L-arginine? Carrier and colleagues stop short of answering that question affirmatively. But their results suggest that the answer may be "yes" and that the question should further be pursued.
L-arginine is a nitric oxide (NO) precursor. In patients with atherosclerotic disease, coronary and peripheral arterial endothelial cells produce reduced amounts of NO. Accompanying this deficit is reduced arterial vasodilatation in response to endothelium-dependent mediators such as acetylcholine, and consequently, reduced flow.
In this study of coronary bypass patients, postoperative serum levels of cardiac troponin T were significantly lower when arginine was added to the cardioplegia than when it was not. Cardiac index and hospital stay were non-significantly improved in the arginine group; a larger series might well demonstrate clinical benefit. The cardioplegia solutions were administered warm (33°C) in 74% of patients and cold (20°C) in the remainder. Although the reduction in troponin levels with arginine cardioplegia is significant in both the entire patient population, and in those given warm cardioplegia, the difference between the arginine and control groups is greater in the warm cardioplegia group: the control group troponin levels are slightly higher and the treatment group levels are slightly lower in the warm group than in the entire study. Although the data are not given, one can conclude that in the cold group, the difference in troponin levels between the control and arginine treated patients is less or even absent. Is the metabolic effect of the arginine temperature dependent, or mediated via temperature dependent enzymes?
Arginine was added only to the first 500 mL of cardioplegia, and with repeat doses given after each distal anastomosis, it appears that subsequent to all distal anastomoses except the first, the arginine treated patients received the same cardioplegia as did the control group. Would the beneficial effect be greater with arginine added to all cardioplegia? Theoretically, administering arginine cardioplegia for all doses, and immediately before reperfusion would improve coronary flow characteristics and further preserve myocyte integrity.
With no apparent deleterious effect, and with significant potential benefit, arginine as a cardioplegia additive deserves further study, and perhaps wider usage.
Related Article
Ann. Thorac. Surg. 2002 73: 837-841.
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |
