Clinical Study Of The Tirofiban Induced Platelet Decrease

BACKGROUND AND AIMSCoronary heart disease is a threatening killer of humanbeings, especially acute coronarysyndrome. In the treatment of ACS,Glycoprotain IIb/IIIa（GPIIb/IIIa) receptor antagonistplays an important role。In the family of GPIIb/IIIa receptor antagonist，tirofiban is widelyused in clinic. Tirofiban hydrochloride is a small-molecule nonpeptide which can bind withmembrane bound GPIIb/IIIa Receptor reversibly. Firstly investigated by Merck&Co.,tirofiban entered the view of clinical doctor in America,1998. After being lead intoChina in2004, tirofiban win the attention of intervention doctor, as a powerful aid in ACStreatment. However, in the way of shortening the period in hospital,as well as decreasing theadverse event, people noticed that some kind of platelet count decrease happened. As apurpose to make sure how the platelet count decrease, we design an experiment as below.METHODSAs a prospective study, from May2014to January2015, we collect about140patientsin our cardiovasculat department of the China-Japan Union Hospital who were suspectedcoronary heart disease. They are grouped into2groups randomly,experiment group andcontrol group,in a2:1way.And some are divided into a subgroup. Their demographic datawas observed, blood samples were drawn2h，6h,9h,12h,24h after tirofiban was used, inexperiment group. As the same thing happened, only the blood samples were drawn right2h,6h,9h,12h,24h after they finish PCI.Collect their admission number, name, sex, age, height,weight, treatment data,as well as their platelet count in the moment describe above. Wedifined thrombocytopenia as platelet count below100×109/L. Then examine the data wecollected.RESULTSIn the experiment group, there are2men who gain mild thrombocytopenia,while nothrombopenia in control group. The time of thrombocytopenia is6-12h and2-9h afterpumping tirofiban, with one gingival bleeding happened. The lowest platelet count of the2patients were95×109/L and87×109/L.No significant change of PLT count could be foundbetween the two groups or between the subgroup of treatment shorter than24hours and the control group, compared with the PLT count of2h. A P value less than0.05was accepted asstatistically significant difference at the period of12-24h. And the difference betweensubgroup of treatment with tirofiban by longer than24hours and the control group seems tobe more significant, while the P value＜0.1in the subgroup of6-9h, and P＜0.05in9-12hand12-24h.CONCLUSION:1. Tirofiban could induce thrombocytopenia, though the rate is low.2. Tirofiban influences the rate of PLT count changing, namely faster in the earlyperiod(6-9h), and slower to pick up(12-24h).3. We suggest to monitor the platelet count dynamicly, especially the early period afterusing tirofiban(2-9h).4. Slow down the speed of drug can reduce the bleeding rate.5. Platelet count is an efficient index to detect the bleeding risk after using tirofiban.