WOEST: Clopidogrel Alone Works Best for PCI Patients on Oral Anticoagulants

MUNICH, Germany—Patients taking oral anticoagulants while undergoing percutaneous coronary intervention (PCI) face heightened bleeding from standard dual antiplatelet therapy with aspirin and clopidogrel. But according to results presented August 28, 2012, at the European Society of Cardiology Congress, one choice is to eliminate aspirin but keep the clopidogrel.

For WOEST (What is the Optimal antiplatelet and anticoagulant therapy in patients with oral anticoagulation and coronary StenTing), Willem Dewilde, MD, of Sint Antonius Hospital (Nieuwegein, The Netherlands), and colleagues randomized 573 patients on oral anticoagulants who were undergoing PCI at multiple centers in the Netherlands and Belgium to clopidogrel 75 mg daily with (n = 284) or without (n = 279) aspirin 80 mg.

Clear Benefits with Just Clopidogrel

Total TIMI bleeding was greater with triple therapy at 1 year, with an early divergence between the group taking all 3 drugs or clopidogrel plus an anticoagulant (HR 0.36, 95% CI 0.26-0.50; P < 0.001; table 1).

Table 1. TIMI Bleeding at 1 Year

 
When bleeding was stratified by type, patients on triple therapy experienced GI, skin, and ‘other’ bleeding rates that were at least double those of patients on clopidogrel and anticoagulants alone.

For the secondary combined endpoint of stroke, death, MI, stent thrombosis, and TVR, dual therapy again bested triple therapy (11.3% vs. 17.7%; HR 0.60, 95% CI 0.38-0.94; P = 0.025). While dual therapy only showed a statistically significant benefit for death (HR 0.39, 95% CI 0.16-0.93), positive trends existed in other individual components (table 2).

Table 2. Ischemic Events at 1 Year

“We propose that a strategy of oral anticoagulants plus clopidogrel but without aspirin to be applied in this group of high-risk patients on oral anticoagulation when undergoing PCI,” Dr. Dewilde concluded.

Eliminating a ‘Taboo’

Commenting on the presentation, Marco Valgimigli, MD, PhD, of the University of Ferrara (Ferrara, Italy), said the study provides a “clear cut answer” to the question of whether it is safe to only use clopidogrel in this patient group.

With regard to the early divergence of events seen between the dual and triple therapy groups, he questioned the how much preventable access site bleeding might contribute. Also, retroperitoneal bleeding, which did differ between the 2 groups, was lumped into the ‘other’ bleeding category. “Therefore, the question of whether and if how much a more systematic limitation of transradial approach in this setting would have prevented this early divergence of the cohorts remains open,” Dr. Valgimigli said.

The main reductions, he noted, were in minor and minimal bleeding, which had a number needed to treat was 4. “Importantly, this complication is [anything but] minor from a clinical standpoint, if occurring in an outpatient center” Dr. Valgimigli observed.

The few issues he took with the study included the fact that as many as 70% of included patients had A-fib. Depending on if the patients were at low risk for stroke, “warfarin could have been discontinued at least for the duration of dual antiplatelet therapy.” Also, he felt the 70% rate of DES in the study was too high.

In addition, Dr. Valgimigli expressed surprise at the numerical reductions in stent thrombosis and stroke with dual therapy. These could either be chance findings, he said, or “another proof of concept that bleeding prevention is more effective in improving outcomes than intensifying antithrombotic regimens.”

Dual therapy with clopidogrel and warfarin “seems a very reasonable therapy . . . especially in DES-treated patients. The taboo of discontinuing or omitting aspirin in the contemporary environment has been broken,” he concluded.

 

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Source:
Dewilde WJM. WOEST: First randomized trial that compares two different regimens with and without aspirin in patients on oral anticoagulant therapy (OAC) undergoing coronary stent placement (PCI). Presented at: European Society of Cardiology Congress; August 28, 2012; Munich, Germany.

 

 

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