Abstract 3164: Combined Antithrombotic Therapy in Atrial Fibrillation. Role of different Antiplatelet Strategies
The NASPEAF trial showed that combined anticoagulant plus antiplatelet therapy was more effective than anticoagulant alone at reducing vascular events in atrial fibrillation (AF) patients. We planned both to validate this benefit during a longer follow-up of patients included in that trial and to assess the hypothesis that combination of anticoagulation plus different antiplatelets could be differently effective and/or safe in patients from that trial and new ones followed-up for at least one year. Methods: Five hundred and seventy-four AF patients were included. Anticoagulation alone therapy (INR 2.0 –3.0) was used as control group (g) 1 to compare with anticoagulation (1.9 –2.5) plus either trifusal 600 mg/d (g2), trifusal 300 mg/d (g3) or aspirin 100 mg/d (g4). Median follow-up was 50, 32, 50 and 37 months respectively. The primary outcome was a composite of ischemic/haemorrhagic stroke, systemic/coronary ischemic events and cardiovascular death. The incidence of severe bleeding was also collected. Anticoagulation was regularly controlled in dedicated units. Results: Long-term follow-up showed benefit of combined anticoagulant plus trifusal 600 mg/d vs anticoagulant alone (primary outcome 2.86% pt/years in g1 vs 1.36% in g2, P=0.014). Combined therapy using other antiplatelet strategies was less effective or safe due to higher incidence of ischemic events when using trifusal 300 mg/d (2.44% pt/years in g3 vs 0.61% in g2, P=0.031) as well as more severe bleeding events with aspirin 100 mg/d (6.60% pt/years in g4 vs 1.51% in g2, P=0.008). Groups g1, g3 and g4 had similar primary outcome (2.86% pt/years, 2.67% and 2.83% respectively). Mean INR and other anticoagulation parameters were similar in the three combined therapy groups. Non-gastric severe bleeding incidence during combined therapy with trifusal 600 mg/d (0.3% pt/years) was lower than that observed in either anticoagulant alone therapy (2.1%, P=0.012) or combined with aspirin (6.60%, P=0.008). In conclusion, long-term follow-up of the NASPEAF trial confirmed the benefit of combined antithrombotic therapy over anticoagulant alone therapy. Combined therapy with aspirin 100 mg/d instead of trifusal 600 mg/d caused higher incidence of severe bleeding.