Simple method to produce acute heart failure by coronary vessel embolization in closed chest rats with microspheres.

Changes in left ventricle (LV) function, systemic, and regional hemodynamics as a result of coronary artery embolization by 15 microns microspheres were studied in rats. Selective coronary embolization was produced by injection of microspheres during ascending aorta occlusion animals by using an "L"-shaped wire in closed chest animals. Maximal developed LV systolic pressure (LVSPmax) was determined during ascending aorta occlusion. Coronary embolization evoked reductions in LVSPmax and +dP/dtmax and then decreased in basal LVSP, dP/dtmax, dP/dtmax/P, with a parallel increase in LV end-diastolic pressure (LVEDP). The number of microspheres accumulating in the heart following coronary embolization was about 40% of the total amount of the injected microspheres (300,000-400,000). In conscious rats 48 hr after coronary vessel embolization (in LV myocardium 100,003 +/- 4,334 microspheres per gram) the cardiac index, mean arterial pressure, -dP/dtmax and stroke volume were reduced by 35.6%, 20%, 17.2%, and 26.7%, respectively, when compared with sham-operated rats. LVEDP was increased by 40%, when compared with sham-operated rats. These results show that in this rat model of coronary vessel embolization heart failure develops. The model created may be used for the studies of pathophysiology of acute heart failure as well as for screening new compounds potentially effective in heart failure.