Prevention of Deep Vein Thrombosis Associated with Temporary Transvenous Cardiac Pacemakers by Enoxaparin

Background: The purpose of this prospective study is to quantify the risk of lower limb deep venous thrombosis (DVT) in patients requiring temporary transvenous femoral pacing and to evaluate the use of different enoxaparin dosages (prophylactic or therapeutic) for thrombus prevention. Transvenous temporary cardiac pacemaker, with catheters frequently used along the femoral vein is useful to relieve difficult bradyarrythmias and some tachyarrythmias. Up to one-third of patients receiving transfemoral pacing develop asymptomatic DVT. At present, there are no recommendations for thrombus prophylaxis in these patients. Besides, the efficacy in this specific condition has not been studied. Methods: Sixty consecutive patients who underwent transvenous femoral pacing and had no contraindication to low molecular weight heparin (LMWH) therapy were divided into 3 groups each group consisted of 20 patients. Group I received prophylactic enoxaparin (1mg/kg/day; subcutaneously), group II received therapeutic enoxaparin (1 mg/kg/day every 12 hours; subcutaneously), and group III consisting of patients who were not treated with enoxaparin was considered as control group. Patients were evaluated daily for clinical features of DVT. Color Doppler sonography imaging was performed on both lower limbs of all patients within 24 hours after removal of the temporary pacemakers. Results: Of the sixty patients, two who belonged to group III, had definitive evidence of right lower limb DVT by color Doppler sonography. These two cases of DVT were asymptomatic and had thrombosis of femoral vein. No evidence of thrombus was detected in contra lateral lower limb. No DVT was detected among patients who received prophylactic or therapeutic doses of enoxaparin. No heparin related complications were detected in this study. There were no significant difference in the clinical characteristics among 2 groups (I, II) and control group. Correlations of age and gender with occurrence of DVT were not significant (P= 0.512, 0.737). Conclusion: This study showed that DVT is a common complication of femoral pacing, and that its incidence can be reduced with the use of prophylaxis and therapeutic intravenous enoxaparin.