[Efficacy of clopidogrel as ADP-dependent platelet aggregation inhibitor. Study on individuals with coronary artery disease].
Acetyl-salicylic acid inhibits thromboxane A2 production and reduces the risk of vascular occlusive events by 20 to 25%. Ticlopidine inhibits ADP-dependent platelet aggregation and reduces the same risk by 30 to 35%, but produces some adverse effects. Clopidogrel is a ticlopidin-derived antiplatelet-drug, with the same mechanism of action; reduces the expression of the glycoprotein IIb/IIIa, the fibrinogen receptor on the platelet surface. Clopidogrel has the same clinical efficacy of ticlopidin and lowers the incidence of adverse effects. In this study, we evaluated the effects of one daily dosis of 75 mg of clopidogrel on platelet function in 33 subjects with coronary artery disease. Before treatment and after the 6th and 12th week, the following parameters were evaluated: 5 microM-ADP and 20 micrograms/mL collagen-induced platelet aggregation, bleeding time and fibrinogen concentration. In basal and in the 6th and 12th week samples, ADP-induced platelet aggregation was 90.7% +/- 13.2, 54.6% +/- 23.2 and 49.2% +/- 23.7 respectively, that represents a significant reduction of 38.6% and 44.4%. Reduction of collagen-induced platelet aggregation was not significative. Plasmatic fibrinogen did not suffer variation during treatment. Bleeding time was significant prolonged from 4.1 minutes to 15.4 and 14.6 minutes (3.7-3.5 times compared with the test before treatment). There were no haemorrhagic complications, only digestive discomfort in fewer than 3% of patients. We concluded that clopidogrel is a safe and efficacious drug for patients, it efficiently reduces ADP-induced platelet aggregation and prolongs bleeding time.
Izaguirre Avila
R
R
Departamento de Hematología y Banco de Sangre, Instituto Nacional de Cardiología Ignacio Chávez, INCICH Juan Badiano No. 1, Col. Sección XVI, 14080, México, D.F.
de la Peña
A
A
González Pacheco
H
H
Ramírez Gutiérrez
A
A
González Valdez
H
H
Quiroz
A
A
Cortina
E
E
Huerta
M
M
Lupi
E
E
D000244:Adenosine Diphosphate; D000328:Adult; D000368:Aged; D000077144:Clopidogrel; D003327:Coronary Disease / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use*
D010975:Platelet Aggregation Inhibitors; D000244:Adenosine Diphosphate; D000077144:Clopidogrel; D013988:Ticlopidine
Eficacia del clopidogrel como inhibidor de la agregación plaquetaria dependiente de ADP. Un estudio en individuos con enfermedad arterial coronaria.