Comparative effects of captopril, nitroprusside, dopamine and lanatoside C on a new model of rabbit congestive heart failure

A new animal model of congestive heart failure that mimics failure of coronary heart diseasL with hypertension was established in rabbits 6-9 d after gradual aortic constriction superimposed on myocardial infarction. The model resulted in significant hypertrophy of the left ventricle and whole heart. an increase of LVEDP (1.7+0.6 vs 0.4+0.3 kPa, p<0.01) and especially significant decreasc of ventricular segmental contraction within the non-infarct area (AL. 0.8+0.4 vs l.4+0.5 mm, p<0.01) as monitored by a sonomicrometer. Comparative evaluation of captopril. nitroprusside, dopaminc and lanatoside C was performed on this model. It was demonstrated that captopril and nitroprus-side significantly lowered the dP/dtmax left ventricular pressure (LVP), and enhanced the segmental contraction; dopamine predominantly increascd dP/dtmax, while lanatoside C manifested significant positive effect on both dP/dtmax and segmental contraction. Vasodilators captopril and nitroprusside were also characterized by a significant reduction of the tension-timc index (TTI). while dopamine increased it.