Improvement of cardiac function in heart failure by antiplatelet therapy

In this study, we tested the hypothesis that sarpogrelate (SAR), a serotonin receptor blocker, and cilostazol (CIL), a phosphodiesterase-Ill inhibitor, which are used as antiplatelet agents, improve cardiac function in congestive heart failure (CHF) due to myocardial infarction (MI). After coronary occlusion for 3 weeks, Sprague-Dawley rats were treated with either 5 mg/kg SAR, CIL or vehicle for 5 weeks; sham-operated rats served as controls. At the end of treatment, the left ventricular (LV) morphology and function were assessed using echocardiography and cardiac catheterization. In comparison to vehicle-treated MI rats, ejection fraction, LV systolic pressure as well as LV pressure development and decay were significantly increased whereas LV diameters, LV end-diastolic volume and LV end-diastolic pressure were significantly decreased in SAR and CIL-treated MI rats. Furthermore, unlike SAR-treated animals, CIL-treated rats showed increased incidence of ventricular tachycardia, which may be associated with an increase in mortality in these animals. These data suggest that both SAR and CIL improve cardiac function in CHF due to MI; however, CIL unlike SAR increased the incidence of ventricular tachycardia and adversely affected the mortality.