Varicose Veins: Endovenous Ablation and Sclerotherapy

Great Saphenous, Small Saphenous, and Perforating Veins

The two major veins of the superficial venous system are the great saphenous vein (GSV) and the small saphenous vein (SSV). ^, True “duplication” of the GSV is rare, and an apparent duplicate GSV is usually an accessory anterior saphenous vein (AASV). ^{, ,} The AASV is found in up to 14% of patients. ^, The GSV otherwise has a relatively consistent pattern of tributaries, including the AASV, posterior accessory GSV, posterior thigh circumflex, and anterior thigh circumflex. ^,

The SSV originates inferior and posterior to the lateral malleolus and ascends the posterior aspect of the calf between the gastrocnemius heads to the popliteal fossa. In two-thirds of patients, the SSV connects to the popliteal vein at the saphenopopliteal junction (SPJ). In the remaining, the SSV may connect to the GSV using the intersaphenous vein (vein of Giacomini) or may have several termination points through its thigh extension. ^{, , ,} A discussion of perforating veins can be found in Chapter 158 (Chronic Venous Insufficiency: Treatment of Perforator Vein Incompetence).

Reticular Veins

Reticular veins are thin-walled venules lying within the superficial compartment with diameters ranging from 1 to 3 mm. ^, They may communicate with the deep system, perforators, or to the superficial system. They may communicate specifically with the saphenous system and form a network of vessels termed the lateral subdermic venous system (LSVS). The LSVS is located along the lateral aspect of the leg and extends above and below the popliteal area. Ultrasound studies have revealed that the reticular veins of the LSVS may connect to telangiectasias in up to 88% of patients.

Telangiectasias

Telangiectasias differ from reticular veins in both size and appearance. Telangiectasias are defined as dilated venules, capillaries, or arterioles 0.1 to 1.0 mm in diameter. ^, The color of a telangiectasia depends on the origin of the vessel. Telangiectasias that arise from the arterial side of the capillary loop are flat and red, whereas those from the venous side are raised and blue. These veins often appear in the thigh near the LSVS. Reticular veins may serve as “feeder” veins to telangiectasias.

Clinical Scoring Systems

Most clinicians have adopted the Clinical, Etiologic, Anatomic, Pathophysiologic (CEAP) system to classify the physical findings associated with chronic venous insufficiency, and the classification was recently revised ( Table 155.1 ). Representative images for the Clinical class may be seen in Figure 155.1 (see also Ch. 156 , Postthrombotic Syndrome: Natural History, Pathophysiology, and Etiology). Any patient in whom an endovenous procedure is contemplated should be evaluated in terms of this classification. Photographs of the target veins should be taken to document the clinical score and to compare the pre- and post-procedural results.

Patient-reported outcomes (PROs) are becoming central to evaluating venous pathology and its meaningful effects on patient quality of life. Scoring systems include the Venous Clinical Severity Score (VCSS), Varicose Veins Symptoms Questionnaire (VVSymQ), Aberdeen Varicose Vein Questionnaire (AVVQ), Chronic Venous Insufficiency Quality of Life Questionnaire (CIVIQ), and others. Patients undergoing endovenous procedures may benefit from the concomitant evaluation of physician- and patient-reported outcomes.

Imaging

Duplex ultrasonography (DUS) of the lower extremities is the standard for evaluating and diagnosing superficial venous insufficiency. Complete evaluation includes assessment of both reflux and obstruction in the deep, superficial, perforating, and tributary veins. A more complete description of the technique can be found in Chapters 20 , Clinical Evaluation of the Venous and Lymphatic Systems and 25 , Vascular Laboratory: Venous Duplex Scanning. The goals of ultrasound are to identify and map the superficial or perforator veins to be treated, and to assess for hemodynamically significant reflux. The deep system should also be interrogated given the potential for altering patient management as the collective experience grows with the treatment of deep venous disease.

Radiofrequency Ablation

RFA is a minimally invasive technology that provides efficacious treatment of superficial venous reflux with minimal post-procedural sequelae typically performed in an outpatient setting. The most commonly used RFA technology uses the “segmental ablation” method employed by the ClosureFast (Medtronic, Minneapolis, MN) procedure ( Fig. 155.2 ). The ClosureFast catheter is constructed such that it makes direct contact with the vein wall to deliver radiofrequency energy, and it ablates at 7-cm intervals. This results in destruction of the endothelium, contraction of vein wall collagen, and thrombus formation. Eventually, fibrosis occurs within the vein, which further constricts its lumen, resulting in a durable ablation. Another recently approved radiofrequency device is Venclose (Venclose, San Jose, CA), which functions on the same principles using a similar “segmental ablation” method but with different lengths of treatment (2.5-cm and 10-cm intervals).

Contraindications to the use of RFA include superficial venous thrombosis (SVT), deep venous thrombosis (DVT), venous aneurysm, and an ankle–brachial index of less than 0.9. Although the presence of a pacemaker is not a strict contraindication, pre-procedural evaluation by the patient’s cardiologist should be considered.

Radiofrequency Ablation Procedure

For ablation of the GSV, the general teaching is to ablate the lowest point of reflux. For C2 or C3 disease, access is initiated no more than a hand’s breadth (∼10 cm) below the popliteal fossa. Should there be evidence of tissue damage (i.e., C4a/b, C5, C6 disease), consideration may be given to ablating further peripherally, taking care to separate the saphenous or sural nerve from the adjacent vein using tumescent anesthesia. To minimize the risk of thermal injury, treatment may be performed where the vein is deep to the saphenous fascia or 1 cm below the skin. With the patient in the reverse Trendelenburg position, lidocaine is administered at the selected site, and a 21-gauge needle is used to gain access under ultrasound guidance. A 0.018-inch guide wire is inserted into the GSV, and the needle is removed. The selected sheath is advanced over the wire, the 0.018-inch wire is removed, and the RFA catheter is inserted. The catheter is advanced to the point where treatment will begin. If it does not advance easily, a 0.025-inch guide wire may be back-loaded into the device to assist passage. Optimal positioning of the catheter tip is 2 to 2.5 cm distal to the SFJ, which is thought to reduce the risk of endothermal heat-induced thrombosis (EHIT), which refers to the extension of thrombus into the common femoral vein. ^,

Once tip placement is confirmed by ultrasound, perivenous tumescent anesthesia is administered under ultrasound guidance along the entire treatment length of the GSV. Tumescent anesthesia serves not only as an anesthetic but also apposes the vein to the catheter and protects the surrounding tissues and skin from thermal damage. ^, Enough fluid should be instilled to create a 10-mm diameter around the vein ( Fig. 155.3 ). A typical tumescent mixture includes 50 mL of 1% lidocaine with epinephrine in 450 mL of normal saline neutralized with 5 to 10 mL of 8.4% sodium bicarbonate. The safe limit for tumescent lidocaine administration has been described as 35 mg per kg body weight.

Many physicians use a pump system with a 22-gauge hypodermic needle to deliver the tumescent anesthesia because it decreases the time needed for administration as well as the number of needle punctures. Ideal needle positioning is within the saphenous compartment. After administration, the patient should be placed in the Trendelenburg position to assist in vein collapse, apposition, and exsanguination. Following treatment completion, the sheath and catheter are withdrawn.

During the procedure, compression over the treated vein and catheter with the ultrasound transducer in a longitudinal position improves vein wall apposition and technical success. With the segmental ablation technique of the ClosureFAST system, each 7-cm segment of vein is treated independently for a 20-second interval. The initial treatment segment 2 to 2.5 cm peripheral to the SFJ requires two 20-second cycles to ensure successful ablation. Aneurysmal or large-diameter segments may be treated twice at the user’s discretion, with a maximum of three treatment cycles. For each 20-second cycle, the temperature must reach 120°C within 5 seconds. The generator monitors all parameters during the treatment cycle and alerts the user if the parameters are not successfully met. After treatment, duplex ultrasonography is utilized to assess the treated vein for ablation, absence of reflux, and DVT.