A randomized, placebo-controlled trial of enoxaparin after high-risk coronary stenting: the ATLAST trial.
OBJECTIVE
We performed a multicenter, double-blind placebo-controlled trial to examine the efficacy and safety of enoxaparin in patients at high risk for stent thrombosis (ST).


BACKGROUND
The optimal antithrombotic regimen for such patients is unknown.


METHODS
We randomized 1,102 patients with clinical, angiographic or ultrasonographic features associated with an increased risk of ST to receive either twice-daily injections of weight-adjusted enoxaparin or placebo for 14 days after stenting. All patients received aspirin and ticlopidine. The primary end point was a 30-day composite end point of death, myocardial infarction (MI) or urgent revascularization.


RESULTS
The target enrollment for the study was 2,000 patients. However, the trial was terminated prematurely at 1,102 patients after interim analysis revealed an unexpectedly low event rate. The primary outcome occurred in 1.8% enoxaparin-treated patients versus 2.7% treated with placebo (odds ratio [OR] 0.66; 95% confidence interval [CI] 0.29 to 1.5, p = 0.30); for death or MI the rates were 0.9% vs. 2.2%, respectively (OR 0.41, 95% CI 0.14 to 1.2, p =0.13); and for MI, 0.4% vs. 1.6%, respectively (OR 0.22, 95% CI 0.05 to 0.99, p = 0.04). The groups had comparable rates of major bleeding (3.3% for enoxaparin, 1.6% for placebo, p =0.08), but minor nuisance bleeding was increased with enoxaparin (25% vs. 5.1%, p < 0.001).


CONCLUSIONS
The clinical outcomes of patients at increased risk of ST are more favorable than previously reported, rendering routine oral antiplatelet therapy adequate for most. However, given its relative safety and potential to reduce the risk of subsequent infarction, a 14-day course of enoxaparin may be considered for carefully selected patients.
Batchelor
W B
WB
The Duke Clinical Research Institute, Durham, North Carolina, USA.
Mahaffey
K W
KW
Berger
P B
PB
Deutsch
E
E
Meier
S
S
Hasselblad
V
V
Fry
E T
ET
Teirstein
P S
PS
Ross
A M
AM
Binanay
C A
CA
Zidar
J P
JP
D000368:Aged; D000704:Analysis of Variance; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001241:Aspirin / Q000627:therapeutic use; D003327:Coronary Disease / Q000628:therapy; D003328:Coronary Thrombosis / Q000517:prevention & control*; D004311:Double-Blind Method; D004333:Drug Administration Routes; D004359:Drug Therapy, Combination; D017984:Enoxaparin / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D015607:Stents / Q000009:adverse effects*; D013988:Ticlopidine / Q000627:therapeutic use; D016896:Treatment Outcome
D000925:Anticoagulants; D017984:Enoxaparin; D013988:Ticlopidine; D001241:Aspirin