Korean J Thorac Cardiovasc Surg.  2001 Sep;34(9):662-671.

Change of Regional Myocardial Blood Flow After Transmyocardial Laser Revascularization in Porcine Model of Chronic Myocardial Ischemia

• Park KH
• Ahn H

Abstract

BACKGROUND: This study was aimed to assess improvement in myocardial perfusion after TMR by measuring regional myocardial blood flow(RMBF) in porcine model of chronic myocardial ischemia. MATERIAL AND METHOD: Ameroid ring was placed around the proximal left circumflex coronary artery in fourteen pigs. After 4 weeks, the control group(7 pigs) underwent rethoracotomy only, and the TMR group(7 pigs) underwent Ho:YAG laser TMR at the circumflex territory. After another 4 weeks, the animals were sacrificed for the measurement of RMBF using colored microspheres. The ratio of RMBF between the circumflex territory and the interventricular septum was calculated and compared. RESULT: At 4 weeks after ameroid constriction, RMBF of the circumflex territory decreased to 46~89% of RMBF of the interventricular septum. In five of six animals in the TMR group, RMBF of the circumflex territory at 8 weeks after ameroid constriction was higher compared with RMBF at 4 weeks after ameroid constriction. However, the improvement was statistically significant only in two animals. In three of the four animals in the control group, RMBF of the circumflex territory also increased at 8 weeks compared with RMBF at 4 weeks. The degree of increase in RMBF was not different between the control and the TMR groups.
CONCLUSION
In porcine model of chronic myocardial ischemia, the degree of increase in RMBF of the ischemic area after Ho:YAG TMR was not different from the increase by development of native collateral circulation. Perfusion of ischemic myocardium after TMR is not thought to improve to the degree that can be demonstrated by currently available method of assessment such as radioisotope myocardial scintigraphy.

Keyword

Coronary artery disease; Myocardial revascularization; Myocardial perfusion; Laser surgery

MeSH Terms

Animals
Collateral Circulation
Constriction
Coronary Artery Disease
Coronary Vessels
Laser Therapy
Microspheres
Myocardial Ischemia*
Myocardial Perfusion Imaging
Myocardial Revascularization
Myocardium
Perfusion
Swine
Transmyocardial Laser Revascularization*