Risk Factors for Thrombotic Complications Studied in Lower Extremity Endovenous Thermal Ablation
January 3, 2018—The Society for Vascular Surgery (SVS) announced the publication of findings from a large, single-center experience with endovenous thermal ablation that reveals risk factors for thrombotic complications. The study was published by Afsha Aurshina, MBBS, et al in Journal of Vascular Surgery Venous and Lymphatic Disorders (2018;6:25–30). The investigators are from Total Vascular Care and New York University Lutheran Medical Center in Brooklyn, New York.
As noted by the SVS, the study's background is that minimally invasive techniques for treating reflux disease in the saphenous system have greatly improved the quality of life and comfort of patients with chronic venous disease and more advanced venous insufficiency. Painful procedures of the past, sometimes including hospital stays, have largely been replaced by safe and efficacious office procedures (often completed in less than an hour) with minimal subsequent activity restrictions.
However, these new therapies have a very low but definite risk of thrombotic complications, including endovenous heat-induced thrombosis (EHIT) superficial venous thrombosis (SVT), and deep vein thrombosis (DVT). EHIT includes development of a blood clot at the junction of one of the treated saphenous veins and the femoral or the popliteal vein.
Major DVT and pulmonary embolism are extremely rare, but the diagnosis of EHIT may require a period of anticoagulation as well as follow-up visits and studies. Further, acute SVT can be painful for several weeks following the procedure. Therefore, further understanding the risk factors for these complications will allow therapists to better inform patients as to their specific risks for developing them, explained the SVS announcement.
The investigators evaluated their large, single-center experience treating multiple vein types using both radiofrequency ablation (RFA) and endovenous laser ablation (EVLA) techniques. They retrospectively studied the outcomes of 1,811 procedures performed on 808 patients from 2012 to 2014. The aim of the study was to better define the success and thrombotic complications of these procedures with respect to technique and vein type.
Rates of overall success (defined as absence of reflux in the targeted vein by postoperative duplex) included:
- RFA, 98.4% (excluding perforating vein)
- EVLA, 98.1%
- Great saphenous vein (GSV), 98.5%
- Lesser saphenous vein (LSV), 98.2%
- Accessory saphenous vein (ASV), 97.2%
- Perforator vein (PV), 82.4%
With regards to thrombotic complications, rates of EHIT were:
- Class 1, 45.9%
- Class 2, 41.16%
Acute superficial thrombosis rates were:
- Overall, 4.6%
- RFA, 7.7%
- EVLA, 11.4% (no difference in multifactor analysis)
- GSV, 11.8%
- LSV, 5.5%
- ASV, 6.5%
- PV, 2.4%
In the SVS press release, Dr. Aurshina commented, “Our study demonstrates that there is no significant difference in the success rate of RFA and EVLA in the treatment of venous reflux for GSV, SSV, and ASV. We found an acceptably low incidence of clinically significant thrombotic complication rates for EHIT and acute superficial thrombosis, with only a 1.16% risk of class 2–4 EHIT, that may require short term anticoagulation. We noted risk factors for these complications, after multifactor analysis, include higher vein diameter and type of vein, with the latter being the most important.”
Large experiences such as these are important to understand the true incidence of these complications and how practitioners might tailor their consent process with their patients, advised the SVS.