EFFECT OF CILOSTAZOL, A NOVEL ANTIPLATETLET DRUG, ON RESTENOSIS AFTERPERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY

The possible preventive effect of cilostazol, a novel anti-platelet dr ug, on restenosis after successful percutaneous transluminal coronary angioplasty (PTCA) was examined. One hundred and two consecutive patie nts, who underwent successful PTCA, were followed for 3 to 6 months. T o prevent restenosis, 46 patients (60 PTCA sites) were treated with ci lostazol alone (200 mg/day) (cilostazol group) and the remaining 56 (6 1 PTCA sites) were treated with other anti-platelet drugs and/or warfa rin potassium (control group). Restenosis was defined as a more than 5 0% loss of the initial gain of the coronary diameter achieved by PTCA. Cilostazol did not significantly reduce the patient or lesion resteno sis rate; the patient restenosis rate was 32% in the control group and 22% in the cilostazol group (P=0.24), and the lesion restenosis rate was 30% in the control group and 23% in the cilostazol group (P=0.44). However, the lesion non-progression rate, which was defined as the in cidence of lesions with either no change or regression of coronary ste nosis at the PTCA site, was significantly greater with cilostazol (37% ) than in the control group (16%) (p<0.05). Although cilostazol failed to show a significant reduction in restenosis after PTCA, the present results suggest that a further trial with a larger number of patients is needed to confirm its usefulness.