ENHANCED ONSET OF PLATELET INHIBITION WITH A LOADING DOSE OF TICLOPIDINE IN ASA-TREATED STABLE CORONARY PATIENTS

Antiplatelet therapy reduces the rate of complications of coronary ang ioplasty. Ticlopidine, in addition to acetyl salicytic acid (ASA), imp roves the results after coronary stenting, but early complications sti ll occur. Ticlopidine given in the standard way has a slow onset of ac tion. Eighteen ASA-treated stable coronary patients were randomized to standard ticlopidine treatment (250 mg twice daily) or to a loading d ose of 1500 mg followed by 250 mg twice daily. After one day, standard treatment had a very modest antiplatelet effect, as assessed by ADP-i nduced platelet fibrinogen binding, whereas the loading dose resulted in a considerably better platelet inhibition; relative inhibition, 5.6 -10.6 vs. 24.9-35.3% (p<0.005) with final ADP concentrations 3 and 0.6 mu M, respectively. It is possible that a loading dose of ticlopidine , given the day before the procedure, might reduce the complications r elated to angioplasty and stenting. (C) 1998 Elsevier Science Ireland Ltd.