Clopidogrel is more effective than aspirin as adjuvant treatment to prevent reocclusion after thrombolysis.
Clopidogrel is a thienopyridine derivative and a potent inhibitor of ADP-induced platelet aggregation. We compared clopidogrel with aspirin as an adjunctive treatment to tissue-type plasminogen activator (t-PA) for thrombolysis and reocclusion. Thrombosis was induced in coronary arteries of 32 dogs by injuring the endothelium with an electric charge. Coronary blood flow velocity was monitored by a pulsed Doppler flow probe placed around the artery. After the artery had been occluded by a thrombus for 3 continuous hours, each animal was given one of the following intravenous treatments: 1) t-PA (80 micrograms/kg + 8 micrograms.kg-1.h-1) and heparin (200 U/kg) (group 1, n = 7); 2) t-PA, heparin, and aspirin (5 mg/kg) (group 2, n = 8); 3) t-PA, heparin, and clopidogrel (5 mg/kg) (group 3, n = 9); and 4) t-PA, heparin, and clopidogrel (10 mg/kg + 2.5 mg.kg-1.h-1) (group 4, n = 8). After treatment, thrombolysis developed in 45 +/- 12 min in group 1, 39 +/- 10 min in group 2, 39 +/- 10 min in group 3, and 27 +/- 10 min in group 4 (compared with group 1, P > 0.05). After thrombolysis, reocclusion occurred in 5 of 5 dogs in group 1 and 7 of 7 in group 2, but only 2 of 7 in group 3 and none of 7 in group 4 (compared with groups 1 and 2, P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
Yao
S K
SK
Cardiovascular Research Laboratory, Texas Heart Institute/St. Luke's Episcopal Hospital, Houston.
Ober
J C
JC
Ferguson
J J
JJ
Maffrand
J P
JP
Anderson
H V
HV
Buja
L M
LM
Willerson
J T
JT
D000818:Animals; D001241:Aspirin / Q000627:therapeutic use*; D000077144:Clopidogrel; D003328:Coronary Thrombosis / Q000188:drug therapy* / Q000517:prevention & control*; D004285:Dogs; D004359:Drug Therapy, Combination; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D012008:Recurrence; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use
D005343:Fibrinolytic Agents; D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin