In vivo porcine model of reperfused myocardial infarction: in situ double staining to measure precise infarct area/area at risk.
OBJECTIVE
The aim of this study is to evaluate a catheter-based porcine model for reperfused myocardial infarction and investigate the appropriate location and duration of the occlusion.


METHODS
A balloon catheter was placed in the left descending coronary artery (LAD) in 78 swine, and used to occlude the LAD. To evaluate this model, left ventricular ejection fraction (LVEF), infarct size, incidence of ventricular fibrillation (VF), and mortality was compared among three groups: 60-min proximal LAD occlusion (60P), 60-min mid LAD occlusion (60M), and 30-min proximal LAD occlusion (30P).


RESULTS
In 72 of the 78 pigs, the procedures were successfully completed. Both mortality and incidence of VF were highest in the 60P group (66.7% and 91.7%, respectively). Myocardial infarction was successfully induced in all 72 animals and in situ double-staining with Evans blue dye and 2,3,5-triphenyltetrazolium chloride was performed to delineate area at risk for ischemia and infarcted myocardium. There was no difference in infarct size, expressed as a percentage of the area at risk, between the 60P and 60M groups (49.5% +/- 3.9% vs. 45.4% +/- 13.3%, respectively). Serial changes in LVEF of the 60M group demonstrated that until 14 days after reperfusion, LVEF improved naturally over time (36.4% +/- 6.6% at 24 hr, and 47.3% +/- 10.1% at 14 days).


CONCLUSIONS
This model and methodology could provide a reproducible and consistent infarct size. The current study demonstrated that 60-min mid LAD occlusion can be the most feasible to serve as a porcine reperfused myocardial infarction model.
Suzuki
Yoriyasu
Y
Division of Cardiovascular Medicine, School of Medicine, Stanford University, Stanford, California 94305, USA.
Lyons
Jennifer K
JK
Yeung
Alan C
AC
Ikeno
Fumiaki
F
D015906:Angioplasty, Balloon, Coronary / Q000295:instrumentation; D000818:Animals; D004396:Coloring Agents; D004195:Disease Models, Animal; D005070:Evans Blue; D009203:Myocardial Infarction / Q000503:physiopathology / Q000628:therapy; D017202:Myocardial Ischemia / Q000628:therapy; D015425:Myocardial Reperfusion; D013318:Stroke Volume; D013552:Swine; D013778:Tetrazolium Salts
D004396:Coloring Agents; D013778:Tetrazolium Salts; D005070:Evans Blue; C009591:triphenyltetrazolium