Clinical, procedural, and pharmacologic correlates of acute and subacute stent thrombosis: results of a multicenter case-control study with 145 thrombosis events.
OBJECTIVE
The aim of this study was to determine correlates of acute/subacute coronary stent thrombosis among unselected patients treated in the era of routine dual antiplatelet therapy and specifically to investigate the influence of prophylactic administration of glycoprotein IIb/IIIa (GpIIb-IIIa) inhibitors and use of clopidogrel versus ticlopidine on the development of coronary stent thrombosis (ST).


BACKGROUND
Because of a relative infrequency of ST events and relatively uniform practice patterns within randomized trials, previous studies have had a limited ability to address whether the use of different antiplatelet regimens at the time of coronary stenting is associated with differences in ST.


METHODS
We performed a multicenter, case-control study to evaluate clinical, angiographic, and pharmacologic/procedural correlates of ST. Between 1996 and 2000, all cases of angiographically-confirmed ST (n = 145) among patients receiving dual antiplatelet therapy were identified from 10 participating clinical sites and were matched with a control without ST randomly selected from the same institution.


RESULTS
Multivariable conditional logistic regression identified higher pre-procedure platelet count, stenting for acute myocardial infarction, use of a coil or self-expanding stent, and overt angiographic thrombus prior to the procedure, as independent predictors of ST (all P < .05). After adjusting for these factors, the use of clopidogrel (vs ticlopidine) was independently associated with an increased risk of ST (OR 2.1, 95% CI 1.0-4.1, P = .04). The use of prophylactic glycoprotein IIb/IIIa inhibitors was not associated with reduced ST in the overall analysis, but appeared to confer some protection against ST within the first 24 hours post procedure (OR 0.5 [95% CI 0.2-1.1] for ST during first day, OR 1.7 [95% CI 0.7-4.3] for ST on subsequent days).


CONCLUSIONS
Both biologic and pharmacologic factors are independently associated with acute/subacute ST. The association between clopidogrel use (vs ticlopidine) and increased ST in this analysis requires confirmation in adequately powered clinical trials and suggests a potential role for newer and more potent antiplatelet agents.
Rinaldi
Michael J
MJ
Beth Israel Deaconess Medical Center, Boston, MA, USA.
Kirtane
Ajay J
AJ
Piana
Robert N
RN
Caputo
Ronald P
RP
Gordon
Paul C
PC
Lopez
John J
JJ
Dauerman
Harold L
HL
Ryan
Thomas J
TJ
Kiernan
Francis J
FJ
Cutlip
Donald E
DE
Ho
Kalon K L
KK
Gibson
C Michael
CM
Murphy
Sabina A
SA
Cohen
David J
DJ
D000208:Acute Disease; D000368:Aged; D000704:Analysis of Variance; D016022:Case-Control Studies; D000077144:Clopidogrel; D017023:Coronary Angiography; D003328:Coronary Thrombosis / Q000453:epidemiology*; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D010976:Platelet Count; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000037:antagonists & inhibitors*; D012307:Risk Factors; D015607:Stents / Q000009:adverse effects*; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use
D010975:Platelet Aggregation Inhibitors; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D000077144:Clopidogrel; D013988:Ticlopidine