ORAL ANTICOAGULANTS added to antiplatelet therapy in patients with peripheral artery disease (PAD) produced no beneficial effect on cardiovascular events compared to antiplatelet therapy alone, according to the WAVE (Warfarin Antiplatelet Vascular Evaluation) study. What is more, the study, which was presented in Hot Line session II and represents the largest anti-thrombotic trial yet in PAD, found that combined therapy produced more lifethreatening bleeds.
“Such strategies have previously worked in patients with coronary artery disease (CAD), but this trial definitively shows combination treatment doesn’t work in PAD – end of issue,” said presenter Sonia Anand (Hamilton, Canada).
Sonia Anand: ‘This trial shows combination
treatment doesn’t work in PAD’
“What’s intriguing about these results is that patients with vascular disease in different locations respond differently to the same therapy. WAVE demonstrates we can not extrapolate from CHD to other vascular diseases.” WAVE’s objective was to determine whether moderate intensity oral anticoagulants in combination with antiplatelet therapy given to PAD patients was superior to antiplatelet therapy alone in preventing cardiovascular death, MI or stroke or severe ischaemia of the coronary or peripheral arterial circulation.
Anand said PAD patients are known to suffer a three-fold excess of cardiovascular death, myocardial infarction (MI) and ischaemic stroke, compared to other vascular patients.
In the study, PAD patients from 80 centres in seven countries were randomised to receive antiplatelet therapy only (n=1,081) or antiplatelet therapy plus oral anticoagulants (n=1,080). Results at 42 months showed 12.2% of patients receiving the combination suffered cardiovascular death, MI or stroke compared with 13.3 % of patients receiving antiplatelet therapy alone (p=0.49). The moderate reduction in MI of 5 % versus 6.1 % was not statistically significant (p= 0.28) and there was no difference in the number of fatal strokes, with 38 in each group.
In addition, 4 % (43 patients) in the combined treatment group suffered life-threatening bleeds compared to 1.2 % (n=13) in the antiplatelet therapy group (p<0.001). Discussant Freek Verheugt (Nijmegen, The Netherlands), congratulated the investigators on the scale of the study. One possible explanation for lack of efficacy in WAVE was the low baseline risk of the study population. More studies with better anti-thrombotics are needed in PAD, he concluded.
Source: ESC Congress News 06 September 2006