|
|
||||||||
Ann Thorac Surg 1994;57:657-662
© 1994 The Society of Thoracic Surgeons
Division of Cardiothoracic Surgery, Medical College of Virginia-Virginia Commonwealth University, Richmond, Virginia USA
Accepted for publication May 25, 1993.
* Address reprint requests to dr Wechsler, Department of Surgery, Medical College of Virginia, MCV Station BOX 645, Richmond, VA 23298-0645.
Thyroid dysfunction has been shown to have a significant impact on hemodynamic status and cardiac function. The purpose of this study was to determine the influence of triiodothyronine (T3) on cardiac functional recovery after ischemia in a dose-dependent manner. Postischemic functional recovery was assessed in isolated rabbit hearts mounted in a modified Langendorff preparation. Left ventricular systolic, diastolic, and peak developed pressures were measured before and after ischemia, and calculated as a percentage of preischemic function. Two cohorts of hearts were studied: the first was exposed to warm ischemia until a myocardial contracture of 4 mm Hg was produced; the second cohort was exposed to warm ischemia until a contracture of 15 mm Hg was observed. In each cohort, T3 was added to the perfusion solution after ischemia in a physiologic concentration (2.5 x 10–9 g/mL; 1 x T3), as well as ten times (2.5 x 10–8 g/ml; 10 x T3 and a hundred times (2.5 x 10–7 g/mL; 100 x T3) the physiologic concentration. One group, given the carrier only but without T3, served as the control. Rabbit hearts exposed to a short period of ischemia (4-mm Hg diastolic contracture) showed increased recovery with 1 x T3 and 10 x T3,100 x T3 did not bring about improved left ventricular recovery versus that in the control group. Rabbit hearts in the 15 mm Hg-diastolic contracture cohort showed increased recovery with 10 x T3 but not with 1 x T3. 100 x T3 led to decreased recovery in this cohort versus that in the control group. T3 supplementation had no influence either on the wet-dry weight ratio of myocardium, measured at the end of reperfusion, or on coronary flow throughout the postischemic period. These findings indicate that T3 enhances recovery after ischemia in a relatively dose-dependent fashion over a wide therapeutic range.
This article has been cited by other articles:
![]() |
Q. Liu, A. S. Clanachan, and G. D. Lopaschuk Acute effects of triiodothyronine on glucose and fatty acid metabolism during reperfusion of ischemic rat hearts Am J Physiol Endocrinol Metab, September 1, 1998; 275(3): E392 - E399. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. D. Klemperer, J. Zelano, R. E. Helm, K. Berman, K. Ojamaa, I. Klein, O. W. Isom, and K. Krieger Triiodothyronine improves left ventricular function without oxygen wasting effects after global hypothermic ischemia J. Thorac. Cardiovasc. Surg., March 1, 1995; 109(3): 457 - 465. [Abstract] [Full Text] |
||||
| 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 |