A new model of chronic cardiac ischemia in rabbits

Chronic cardiac ischemia has mainly been studied in large species such as p igs or dogs. Little research has been performed using small species such as rabbits. In the present study, 1-3 wk after implantation of a novel device (ameroid) on the circumflex coronary artery of New Zealand White rabbits, vessel patency was evaluated by coronary angiography, corrosion cast, and r adiolabeled microspheres. Coronary angiograms showed, after 21 days, either total occlusion or severe stenosis in seven of eight arteries, which was c onfirmed by corrosion casts. The ameroid group had less blood flow in the e picardial (-62%) and endocardial (-54%) layers of the ischemic area compare d with sham-operated rabbits (P < 0.05). Blood flow increased in the ischem ic area compared with day 0 during acute occlusion, suggesting that progres sive coronary occlusion initiated the growth of de novo collateral vessels. Thus we have developed a new model of chronic cardiac ischemia in rabbits with documented progressive coronary stenosis and occlusion that is suitabl e to test various therapeutic angiogenesis strategies.