by Eric Mowatt-Larssen, MD, RPhS
Approximately 25% of patients presenting to a vein clinic have combined superficial and deep venous reflux on duplex ultrasound. These patients tend to have more severe venous disease. Ulcers and skin changes are more common. Pain and swelling tend to be worse. These patients also have the most to gain from well-planned and well-executed treatments. Potential benefits include a reduced ulcer recurrence risk, possibly a faster ulcer healing rate, and decreased pain and swelling. As shown in Figure 1 (page?44) from Labroupolos et al, superficial venous reflux remains highly prevalent (over 80%) in patients at all levels of venous clinical severity. Isolated saphenous reflux is common in patients in cEAP classes 1-3. Saphenous reflux, however, is usually combined with deep and/or perforator reflux in patients with venous skin changes or ulcers.
Deep venous obstruction
As with any venous patient, ruling out deep venous obstruction is the first step. Lower extremity duplex ultrasound is a sensitive and specific test to rule out femoropopliteal obstruction. Although the idea has been challenged, chronic deep venous obstruction is generally considered a contraindication to superficial reflux treatment because the superficial veins can act as important collaterals.
Patients can also have more proximal deep venous obstruction missed by lower extremity ultrasound. Obstruction of the iliocaval system, for example, occurs from thrombosis as well as anatomic compression, such as May-Thurner Syndrome (compression of the left iliac vein by the right iliac artery). Around 33% of patients with iliac vein obstruction have no femoropopliteal reflux,so a normal lower extremity duplex does not rule out the disease. This diagnosis is likely often missed. Figure 2 (page?44)?lists clues to patients in whom the diagnosis of iliac vein obstruction should be considered. Venous symptoms out of proportion to reflux findings is a key symptom. An example would be a patient with diffuse, moderate or severe, venous-sounding extremity pain and swelling (worsens with dependence, improves with elevation, associated with visible varicosities), but only minimal segmental saphenous reflux on ultrasound. Venous claudication (thigh or calf pain or discomfort which starts with vigorous exercise and subsides with rest) may be a reasonably specific but insensitive symptom. Pelvic collaterals visualized on physical examination also suggest the diagnosis. Another important clue is a history of or ultrasound findings consistent with prior deep venous thrombosis (Figure 3, page 44).
Iliac vein obstruction diagnosis is dependent on the skills and experience of the physician. Venography, intravascular ultrasound, magnetic resonance venography, and computed tomographic venography all have advocates. Stenosis of greater than 50% is often used as a cutoff for clinically significant stenosis. Results of treatment with venous stenting are good clinically (symptoms relief) and technically (patency rates), especially in non-thrombotic cases.
Mangement of superficial reflux
Most patients with combined saphenous and deep venous reflux improve clinically when the saphenous vein is treated. Knipp et al looked at this question specifically. Patients were treated with saphenous laser ablation with or without phlebectomy. In this study, patients did just as well whether they had deep venous reflux or not in term of clinical improvement (venous clinical severity score improvement) or risk of complications, like deep venous thrombosis. Other studies have shown more clinical improvement in the saphenous reflux alone group than the combined saphenous-deep reflux group. Marston et al found that patients with maximal reflux flow velocity less than 10 cm/s in the femoral or popliteal systems did better clinically than those with higher velocities after endovenous saphenous ablation, although patients in both groups showed clinical improvement.
The EScHAR (gohel et al) study showed that, in patients with active or recent ulceration, saphenous treatment combined with compression reduces ulcer recurrence risk at 4 years by 25% (56% vs. 31%) compared to compression alone. Some patients received high ligation without stripping under local anesthesia if it was felt they would not tolerate general anesthesia, which would be considered a suboptimal treatment by many in an age with endovascular techniques performed routinely under local anesthesia. As shown in Figure 4 (page?44), patients in the subgroup with segmental femoropopliteal reflux also benefited from saphenous treatment. Patients with total femoropopliteal reflux showed a trend towards benefit without statistical significance in this study. Saphenous treatment did not increase wound healing rate in EScHAR, but patients did have more time free of ulcers. Other data do show an improved ulcer healing rate with superficial venous treatment. Ulcer healing rates are likely affected by ambulatory venous pressure as well as other significant factors like patient compression compliance, wound surface area, and wound depth, which confound the benefit of saphenous correction.
Hemodynamically, the results of saphenous treatment for combined saphenous-deep reflux are more equivocal. Isolated common femoral vein reflux often corrects with great saphenous vein ablation. common femoral vein reflux, however, is often caused simply by the failure of the terminal valve of the great saphenous vein. correction of common femoral vein “reflux” in this scenario is simply the correction of a superficial valve. combined femoropopliteal or popliteal vein reflux alone corrects less often.
Deep venous reflux can arise both from primary valve failure as well as post-thrombotic valve damage from deep venous thrombosis. Venous overload is likely another cause of reflux. Extra venous volume-is transmitted anterograde or retrograde, resulting in increased pressure, venous dilatation, and valve failure. When venous overload is corrected by ablation, reflux corrects also. Venous overload may also play a part in perforator incompetence, as discussed later.
In the absence of deep venous obstruction, then, the patient’s saphenous system and secondary varicosities (varicose saphenous tributaries or localized varicosities remaining after saphenous ablation) can often be treated in a standard fashion despite the deep venous reflux. Ablation of saphenous and/or secondary varicosity reflux can be perfomed in a concomitant or staged fashion, at the discretion of the physician. With current techniques, thermal ablation (laser or radiofrequency) or surgery (high ligation and stripping) are generally preferred for saphenous ablation, while chemical ablation (sclerotherapy) or surgery (ambulatory phlebectomy) are preferred for secondary varicosities.
Management of incompetent perforator veins Incompetent perforator treatment is an area of controversy. As shown in Figure 1 (page?44), the presence of incompetent perforator veins, like deep venous incompetence, is associated with more severe chronic venous disease. Treatment of incompetent perforator veins, however, has not been shown to impact patients clinically independently from saphenous ablation. Such a study will be hard to do because of the rarity of perforator incompetence in the absence of superficial or deep venous reflux (0% in Figure 1).
In the absence of decisive clinical data, the physician is left with clinical judgment. Incompetent perforator veins are usually corrected only in patients with advanced venous disease, such as active or historical ulcers. Incompetent perforator veins often correct after saphenous ablation, however. Stuart et al found that, after saphenous ablation, 80% of incompetent perforator veins corrected when the deep veins were normal, but only 28% corrected when significant reflux remained in the deep or superficial veins. The saphenous reflux should be treated first, and should be followed by a recheck duplex ultrasound study before incompetent perforator treatment.
Techniques for Incompetent perforator ablation include thermal ablation (laser or radiofrequency), chemical ablation (ultrasound-guided foam sclerotherapy) or surgery (subfascial endoscopic perforator surgery). Incompetent perforators can be divided theoretically into reentry and pathologic perforator veins. Reentry perforators are incompetent only because they carry volume-overload from the saphenous or secondary varicosity systems. They have systolic as opposed to diastolic reflux. On spectral analysis, they show more drainage volume-(flow from superficial to deep veins) than reflux (flow from deep to superficial) volume. These veins often become competent when the saphenous overload is eliminated with an ablation.
Pathologic perforators typically carry volume-overload from refluxing deep veins or may be the source of reflux. Such perforators will show diastolic reflux on ultrasound and result in a reflux volume-exceeding drainage volume-on spectral analysis. Figure 5 provides an example. In this case, a thigh perforator refluxes through visible painful varicosities into the below-knee great saphenous vein. The thigh great saphenous vein had been successfully ablated several years earlier. The reflux reenters the deep system through a distal calf perforator. The thigh perforator is pathologic and acts like a saphenofemoral junction. The calf perforator acts as a reentry perforator draining the leg.
Management of deep venous reflux
For the patient with remaining severe symptomatic reflux despite successful treatment of refluxing saphenous, secondary varicosities, and pathologic perforator systems, there are options to treat deep venous reflux. These therapies are generally performed only at specialized centers. Valvuloplasty is generally the preferred technique when it is possible, but post-thrombotic valves sometimes are difficult to correct. Axillary vein transfer is another option. Wound complications, such as seroma or hematoma, and deep venous thrombosis are potential complications. Patients with primary valvular disease usually do better than post-thrombotic patients.
Conclusions and opportunities
Figure 6 (page?44)?outlines a proposed pathway for the treatment of patients with mixed deep and superficial reflux. This pathway is in fact no different than how patients without concomitant deep and superficial reflux are treated. There are some key differences, however. First, patients with combined reflux tend to have more severe symptoms and can receive the greatest benefit from treatment. Second, they are more likely to have deep venous obstruction. There should be a lower threshold to investigate these patients for iliac vein obstruction. Third, patients with combined reflux may get less clinical improvement with treatment compared to those with superficial reflux alone because of their poorer overall extremity hemodynamics. It is important to adjust patient expectations in the combined reflux group.
There are many opportunities for research in patients with mixed deep and superficial reflux. Defining the group of patients with deep venous obstruction with good collateral flow and who would benefit from saphenous treatment would be helpful. The data shows mixed results in the ability of saphenous correction to increase ulcer healing rates. A better understanding of venous hemodynamics may allow development of surgical and endovascular strategies and techniques to improve venous ulcer healing rates reliably. Management of incompetent perforator veins is a controversial area and difficult to study because isolated perforator vein reflux is rare. One option is to look for outcome differences in patients with combined saphenous and perforator reflux with saphenous only treatment versus saphenous plus perforator treatment. Treatment for incompetent deep venous valves will likely continue to evolve as well.