Femoral vein thrombosis after right-sided electrophysiological procedures.

Purpose: Electrophysiological studies and radiofrequency catheter ablations require single or multiple sheath placements through femoral vein cannulation. The objective of this study was to determine the incidence, predictors, and outcomes of deep vein thrombosis (DVT) following such procedures.

Methods And Results: We prospectively enrolled 220 consecutive patients with a median age of 70 [60-79] years. The median duration of the procedures from insertion to removal of sheaths was 45 [30-75] min. At least two sheaths were inserted in 158 (72%) of the cases. Duplex ultrasonography evaluation of the lower leg veins was performed 6 h after the procedure and revealed common femoral vein thrombosis in 11 (5%) patients. All thrombi were partial and none was complete. Thrombi were mobile in four patients and extended to the external iliac vein in three patients. None of the patients presented with clinical signs of DVT or pulmonary embolism. Anticoagulation was prescribed for 2-4 weeks and a follow-up duplex ultrasonography obtained in the first seven patients revealed complete resolution of thrombi in all cases. On multivariate analysis, two predictors of thrombosis occurrence were identified: a greater sum of sheath diameters (odds ratio, 1.41 [95% confidence interval, 1.25-1.60] per 1-French increase; p < 0.001) and a longer procedural duration (odds ratio, 1.02 [95% confidence interval, 1.00-1.04] per 1-min increase; p = 0.04).

Conclusions: Asymptomatic femoral DVT occur in 5% of electrophysiological studies and right-heart radiofrequency catheter ablations, particularly when large sheaths are inserted for a longer period. The role of anticoagulation in this clinical setting warrants further evaluation.