The applicant points out that myocardial dysfunction associated with coronary artery disease may be due to infarction, viable but stunned or viable but hibernating myocardium. The applicant seeks to determine whether hibernating myocardium that is not treated with revascularization will result in progressive myocardial cell death and fibrosis, resulting in worsening heart failure. He describes the pig model of hibernation developed in his laboratory in which a chronic partial stenosis is placed on the coronary artery of a pig. The hypotheses are: 1. That myocyte cell death and fibrosis worsen as the duration of hibernation is prolonged, 2) that frequent episodes of demand ischemia will worsen the outcome; and 3) that beta blockers will attenuate the phenomenon. Daily dobutamine infusions will be used to try to exacerbate the progression of cell death and fibrosis. Beta blockers will be used to ameliorate the proposed worsening. It is hoped that this study will provide strategies for treating ischemic cardiomyopathy and end-stage heart failure.
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Chen, C; Liu, J; Hua, D et al. (2000) Impact of delayed reperfusion of myocardial hibernation on myocardial ultrastructure and function and their recoveries after reperfusion in a pig model of myocardial hibernation. Cardiovasc Pathol 9:67-84 |
Lai, T; Fallon, J T; Liu, J et al. (2000) Reversibility and pathohistological basis of left ventricular remodeling in hibernating myocardium. Cardiovasc Pathol 9:323-35 |