Chronic venous disease manifests clinically as a broad spectrum of disorders ranging from cosmetically distressing spider veins to painful varicose veins and to longstanding venous stasis ulceration. While an enormous amount of health care resources are focused on the treatment of arterial disease, venous disorders are at least 4 to 5 times more prevalent than arterial disease. In the past, saphenous vein reflux and varicose veins were treated with vein stripping surgery. Recently, minimally invasive endovenous ablation techniques of the greater and lesser saphenous veins have revolutionized treatment options. Instead of removing the saphenous vein, the current approach involves ablating the saphenous system in situ, thus stopping retrograde flow and replacing the vein with fibrous tissue. Currently, two competing technologies are used in the United States to accomplish this goal: endovenous laser ablation (EVLA) and radiofrequency ablation (RFA). As their names imply, these two catheter-based treatment modalities employ different means to generate the energy and heat used to destroy the saphenous vein. These endovenous techniques are used to ablate refluxing veins including the greater (long) saphenous vein (GSV) and its anterior saphenous branch, as well as the lesser (short) saphenous vein (LSV).
While the preoperative assessment is identical regardless of the ablation technology used, radiofrequency ablation of the saphenous system will be the focus of this review. In the United States, only one company (VNUS Medical Technologies, Inc.; San Jose, California) manufactures an RFA device approved for commercial use for the treatment of saphenous vein disease. Although the company's original ClosurePLUS RFA catheter demonstrated excellent results, it was replaced in 2007 with a newer ClosureFAST catheter that allows for more rapid, segmental ablation. Trial outcomes are expected to be similar to the previous model's results. However, data on venous ablation techniques are limited, and most RFA reports have focused on safety and efficacy of the original catheter configuration.
EPIDEMIOLOGY
Venous insufficiency results from inadequate drainage of a vein segment caused by valvular incompetence. This results in enlargement of the main trunk or a branch of the saphenous system. Recent studies suggest that 5% to 30% of the adult population have varicose veins.1 Varicose vein prevalence is greater in industrial, developed countries than in underdeveloped nations and is therefore a major medical problem in the United States and Europe. One Italian study of 30,000 subjects identified a 7% prevalence of varicose veins identified by a combination of clinical assessment and ultrasound evaluation.2 In the United States, the Framingham Heart Study reported that 1.9% of men and 2.6% of women developed varicose veins each year. Most studies identify a female predominance of varicose veins, with a US population study reporting 28% of women and 15% of men affected by this problem.3 In contrast, a UK study suggested the opposite may be true in countries outside the United States, with males affected more frequently (40%) than females (32%). While the prevalence of chronic venous disease varies depending on practice location, it remains among the most common disorders encountered in any active clinical practice environment. Risk factors associated with the development of chronic venous disease include female gender (potentially due to effects of hormones and pregnancy), family history, history of deep vein thrombosis (DVT), advancing age, obesity, and prolonged standing.1,4,5 Hispanics and whites are more commonly affected than those of African American or Asian ancestry.
Millions of Americans annually seek treatment for cosmetically distressing or symptomatic venous disorders. Approximately 5 million Americans suffer from chronic venous disease symptoms. In its most advanced clinical manifestation, venous stasis ulceration, which occurs in 1% of patients, results in the loss of 2 million workdays annually and early retirement in 12.5% of affected workers.6 In the United States and Western Europe, 1% to 2% of annual health care spending is devoted to the cost of treating venous disease, and in the United States roughly $3 billion is spent on treating venous wounds each year.7,8
MANIFESTATION OF CHRONIC VENOUS DISEASE
Venous disease patients most frequently present with small (less than 3 mm) veins visible on the surface of the skin or larger (greater than 3 mm) varicose veins that may be visible or only palpable in SC adipose tissue. Advanced symptoms may include peripheral edema, hyperpigmented or indurated skin changes, or even healed or active ulceration. The CEAP classification describes the Clinical, Etiologic, Anatomic, and Pathophysiologic components of chronic venous disease, and this clinical grading system is routinely used (Table 1).9 The patient's symptoms correspond to the severity of clinical disease. Patients with telangiectasias (spider veins) and varicose veins may have minimal complaints or be asymptomatic. Typically, patients with varicose veins complain of leg aching or heaviness after prolonged standing, swelling involving the ankle, and relief of these symptoms by leg elevation or the use of compression support. Stagnant blood in varicosities can also result in the development of superficial thrombophlebitis. Continued chronic high venous pressures in engorged surface veins in the perimalleolar area results in extravasation of red blood cells into the surrounding SC tissues. This causes hemosiderin deposition that causes hyperpigmented and fibrotic skin changes. If left untreated, these skin changes can progress to the development of venous stasis ulceration.