The characteristics of the 5-HT_2A receptor antagonist sarpogrelate and the PDE III inhibitor cilostazol on heart rate, electrocardiogram and blood pressure in peripheral circulatory disorders

The incidence of peripheral occlusive diseases increase from year to year. Through the individual treatment, the management of heart rate, myocardial damage and blood pressure, including influential factors to peripheral flow, and the prevention of progressive circulatory disorders are important. In this study, 78 patients with peripheral occlusive diseases were investigated based on influences of these factors before and after administration of sarpogrelate and cilostazol as antiplatelet agents. Sarpogrelate was insignificant except the shortening in QTc in prolonged QTc. Cilostazol had the increase in heart rate, the prolongation in QTc in normal QTc and the reduction of diastolic blood pressure in cases along with increase in heart rate. Above mentioned results may be explained from their different concentration of intracellular Ca that influences on the slope of diastolic depolarization in pacemaker cells (heart rate) and the plateau of action potential in myocardial cells (QTc). Sarpogrelate as a 5HT₂ receptor antagonist and cilostazol as a PDE III inhibitor promotes a decrease and an increase in intracellular Ca, repectively. The restoration of myocardial damage and the unchanged heart rate and blood pressure using sarpogrelate can be useful in elderly patients, and expected to prevent the serious conditions. Cilostazol may be better in point of the insufficiency of peripheral flow as a result of bradycardia.