OBJECTIVES: To evaluate the efficacy of prophylactic use of warfarin in patients with high risk of lead-associated thrombosis. METHODS: Clinical, prospective, randomized and blinded study, in patients submitted to first transvenous leads implantation with LVEF <0.40 and/or previous ipsilateral temporary pacing. After device implantation, patients were randomly assigned to placebo or warfarin. Periodical clinical and laboratorial evaluations were performed to anticoagulant management. After a six-month period, every patient was submitted to a digital subtraction venography. From February 2004 to November 2006, 101 patients underwent randomization. Baseline characteristics were similar in both groups (P=NS). RESULTS: Venographic analysis showed 31.4% of venous obstructions in patients assigned to warfarin as compared with 57.1% in patients assigned to placebo (RR= 0.57 [95% CI, 0.33 to 0.98]; P=0.015). In the warfarin group, 72% of the PT/INR tests were in therapeutic INR range. Only one patient required warfarin discontinuation and cross-over to placebo group due to gastrointestinal bleeding. CONCLUSIONS: These preliminary results showed that the anticoagulation therapy has been safe and reduced the frequency of venous thrombosis after transvenous cardiac devices implantation in high risk patients.
Cardiac pacing, artificial; Postoperative complications; Venous thrombosis; Anticoagulants; Clinical trial
