Short-term prevention of thromboembolic complications in patients with atrial fibrillation with aspirin plus clopidogrel: the Clopidogrel-Aspirin Atrial Fibrillation (CLAAF) pilot study.
BACKGROUND
We evaluated the short-term safety and efficacy of aspirin-plus-clopidogrel as antithrombotic therapy in nonvalvular atrial fibrillation (AF).


RESULTS
Thirty patients (11 women, 45 to 75 years of age) with non-high-risk permanent (n = 12) or persistent AF awaiting cardioversion (n = 18) underwent transesophageal echocardiography to exclude left heart thrombi and were then randomly assigned to receive warfarin (international normalized ratio, 2 to 3 for 3 weeks) or aspirin (100 mg/d alone for 1 week)-plus-clopidogrel (75 mg/d added to aspirin for 3 weeks). Bleeding time and serum thromboxane B2 were measured at entry and at 3 weeks. Bleeding time, not affected by warfarin, was prolonged by 71% by aspirin (P <.05) and further, by 144%, by adding clopidogrel (P <.01 vs aspirin alone; +319%, P <.01, vs baseline). Thromboxane B2, not affected by warfarin, was reduced by aspirin (-98%, P <.01) but not further by clopidogrel. No thrombi or dense spontaneous echo-contrast were found at the 3-week transesophageal echocardiography. Seven of 9 patients receiving warfarin and 7 of 9 patients receiving aspirin-plus-clopidogrel, undergoing electrical cardioversion, achieved sinus rhythm. No thromboembolic or hemorrhagic events occurred in both arms throughout the 3-week treatment and a further 3-month follow-up.


CONCLUSIONS
Aspirin-plus-clopidogrel and warfarin were equally safe and effective in preventing thromboembolism in this small group of patients with non-high-risk AF.
Lorenzoni
Roberto
R
Department of Cardiology, Campo di Marte Hospital, Lucca, Italy.
Lazzerini
Guido
G
Cocci
Franca
F
De Caterina
Raffaele
R
D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use; D001241:Aspirin / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000150:complications / Q000188:drug therapy* / Q000628:therapy; D001760:Bleeding Time; D000077144:Clopidogrel; D004359:Drug Therapy, Combination; D017548:Echocardiography, Transesophageal; D004554:Electric Countershock; D005260:Female; D006801:Humans; D019934:International Normalized Ratio; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D013923:Thromboembolism / Q000517:prevention & control*; D013929:Thromboxane B2 / Q000097:blood; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D014859:Warfarin / Q000627:therapeutic use
D000925:Anticoagulants; D010975:Platelet Aggregation Inhibitors; D013929:Thromboxane B2; D014859:Warfarin; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin