Surgical Treatment of Lower Extremity Deep and Perforator Vein Incompetence




Historical Background


In 1968 Kistner was the first to describe direct surgical repair of incompetent deep venous valves. Indirect valve repair was first popularized in the early 1980s after report of the axillary vein transfer technique, which was followed by Gloviczki and colleagues’ description of angioscope-assisted external repair of venous valves in 1991. Surgical interruption of incompetent perforating veins to mitigate the effects of venous hypertension and promote venous ulcer healing was first described by Linton in 1938. Relatively high wound complication rates limited this approach, and as a minimally invasive alternative, subfascial endoscopic perforator surgery (SEPS) was first described in 1985 by Hauer in Germany and was subsequently popularized in the United States by Gloviczki and associates.




Indications


Deep Venous Valve Surgery


Indications for deep vein valve surgery include venous valve reflux in the presence of intractable, advanced symptoms of lower extremity chronic venous insufficiency (CEAP classes C4-C6), or the presence of significant pain that interferes with quality of life. Typically, intervention follows long-standing compressive therapy and the correction of iliac or iliofemoral venous outflow obstruction, and superficial or perforator vein reflux. Lower extremity axial reflux is present that extends from groin to calf, along with an incompetent deep venous valve, which is amenable to direct surgical repair, or a postthrombotic vein segment that is suitable for indirect repair or replacement.


Subfascial Endoscopic Perforator Surgery


The role of perforating vein surgery in treating symptoms of venous insufficiency remains controversial. Chronic venous insufficiency (CEAP C4-C6) with a medially located leg ulcer in association with perforator vein reflux of greater than 3.5 seconds on duplex scan are usually present. Appropriate candidates for intervention are those patients with low operative risk and acceptable ambulatory status without significant peripheral arterial occlusive disease, calf pump failure, morbid obesity, or a hypercoagulable state.




Preoperative Preparation


Deep Venous Valve Surgery





  • Preoperative diagnostic workup should include lower extremity arterial and venous duplex studies.



  • Ascending and descending venography is performed to identify the sites of reflux and obstruction. When proximal venous obstruction is suspected in the iliac system, intravascular ultrasound should be performed, because it is often superior to conventional venography at diagnosing venous stenoses.



  • Duplex imaging of the axillary veins can be performed to evaluate its suitability as a donor segment for lower extremity valve transplantation.



  • Assessment for underlying thrombophilia is indicated to guide postoperative anticoagulation.



  • A sequential compression device is applied at the time of anesthesia to decrease the risk of deep vein thrombosis (DVT) and postoperative edema.



Subfascial Endoscopic Perforator Surgery





  • Duplex imaging is performed preoperatively to identify the number, location, and size of incompetent perforators and to evaluate the superficial and deep venous systems.



  • The day before surgery perforators are marked on the skin with a semipermanent marker.



  • Preoperative and postoperative strain gauge or air plethysmography may be used as a physiologic tool to evaluate the impact of treatment on the degree of valve incompetence, calf muscle pump function, outflow obstruction, and related hemodynamic changes.



  • Prophylactic low-molecular-weight heparin may be considered during the perioperative period, especially in patients with a prior history of DVT.





Pitfalls and Danger Points


Deep Venous Valve Surgery





  • Deep vein thrombosis. The risk of DVT in deep vein valve surgery is less than 5%, but may involve the site of repair, the distal venous system, or the opposite unoperated limb. Sequential pneumatic boots, heparin prophylaxis, and perioperative anticoagulation may help diminish the risk of DVT. Lower extremities should be elevated in the postoperative period until the patient is ambulatory to decrease venous stasis and edema.



  • Hematoma. Meticulous hemostasis is required and a drain left at the operative site, particularly, if postoperative anticoagulation will be instituted.



  • Incompetent reconstructed valve. The construction of a neovalve or vein valve transfer can be considered if direct repair is unsuccessful.



Subfascial Endoscopic Perforator Surgery





  • Missed perforators. Failure to identify incompetent perforators that may be located in the intermuscular septum, paratibial, or retromalleolar region may contribute to delayed ulcer healing or a recurrent ulcer. The medial insertion of the soleus muscle may need to be exposed to visualize proximal paratibial perforators. Retromalleolar, lower posterior tibial perforators cannot be reached by current endoscopes and, if incompetent, may need to be interrupted by an open technique.



  • Nerve injury. Damage to the saphenous nerve, which runs along the saphenous vein below the knee, can cause dysesthesia and a loss of sensation along the medial aspect of the lower leg. In addition, the tibial nerve runs posterior to the medial malleolus into the foot and is also at risk of injury. Tibial injury may present as dysesthesia and weakeness of the foot and toes.



  • Infection. The risk of a surgical site infection is increased in the presence of an open ulcer, even if remote from the surgical incision. The procedure should be deferred in the presence of active cellulitis and prophylactic antibiotics considered routine.



  • Deep vein thrombosis



  • Hematoma





Operative Strategy


Deep Venous Valve Surgery


Direct valve repair is used more often for patients who present with primary valvular incompetence, whereas deep vein valve reconstruction, such as vein valve transfer, is most often performed for those with postthrombotic syndrome.


Proximal Venous Obstruction


Patients who present with an incompetent deep venous valve and a concomitant iliocaval venous stenosis should first undergo treatment of the obstruction, typically by venous stenting. Relief of pain and edema may be achieved in a substantial number of patients even in the presence of persistent deep valvular incompetence.


Selection of Valve Site for Repair


Femoral vein, profunda femoral vein, popliteal vein, and posterior tibial vein valves are all amenable to repair. Repair of a single incompetent valve, most commonly the proximal femoral vein valve, is sufficient in most cases of primary venous insufficiency, whereas for those patients with postthrombotic syndrome, if present, an incompetent profunda femoral vein valve should be repaired as well.


Avoiding Early Deep Vein Thrombosis at the Site of Valve Surgery


Surgical manipulation should be minimized to preserve normal vein morphology and limit endothelial damage. Closure of a venotomy should be performed with everting sutures to avoid creation of a thrombogenic nidus. External valvuloplasty carries risk of stenosis because of improper placement of sutures with a stenosis that exceeds 20% dictating the potential need for vein valve transfer.


Anticoagulation


Intravenous heparin is administered should vein clamping be required. Low-molecular-weight heparin should be continued postoperatively and then converted to warfarin. Duration of anticoagulation is patient specific but usually continues for a minimum of 2 to 4 months.


Avoiding an Incompetent Venous Valve Repair


Once a valve repair has been completed and the venotomy closed, intraoperative assessment of valve competence should be conducted. In the strip test, the distal inflow vein segment is temporarily occluded and blood is milked across the valve by sliding a finger upward against the wall. Blood is then forced back against the valve. If the vein below the valve remains collapsed, then the valve is competent; if incompetent, refilling of the emptied distal vein segment will be observed. An intraoperative duplex study of the repaired valve or reconstructed vein segment can also be performed. Surgical correction of an incompetent repair should be performed and, if unsuccessful, axillary vein valve transfer considered.


Subfascial Endoscopic Perforator Surgery


SEPS can be performed in the presence of an open but not an infected ulcer; however, patients with extensive skin changes and circumferential leg ulcers should not undergo SEPS. If there are signs of cellulitis or erysipelas, pain, erythema, and purulent discharge, antibiotics and local treatment should be initiated before surgery. Small upper calf incisions should be placed remote from the ulcer or affected skin. Proper wound cleaning before the procedure and coverage of the extremity with a transparent, occlusive dressing will help minimize intraoperative bacterial contamination and surgical wound infection.




Operative Technique


Deep Venous Valve Surgery


General or spinal anesthesia can be used for deep venous valve surgery. The patient is positioned supine with the thigh slightly externally rotated. The common femoral vein, femoral vein, great saphenous vein, and profunda femoral vein can be exposed through a groin incision; dissecting through the sartorius muscle fascia helps expose the profunda femoral vein. The popliteal vein can be exposed by a supragenicular, an infragenicular, or a posterior approach. Target veins and their branches are isolated by blunt dissection for several centimeters. Although the attachment lines of primary incompetent valves are readily identifiable on inspection, postthrombotic veins are often surrounded by thickened, fibrous periadvential tissue, which will need to be sharply dissected to expose the segment to be treated. Absent or incomplete valve leaflet attachment lines predict a nonrepairable, destroyed valve that is not suitable for direct repair.


Valvular Repair Techniques


Internal Valvuloplasty


Most primary incompetent valves and some valves affected by postthrombotic changes are amenable to direct valvuloplasty. In the classic Kistner procedure, a longitudinal venotomy is performed between the valve cusps 1 to 1.5 cm below the valve attachment lines with extension using a Potts scissors through the anterior commissural apex. Plicating 7-0 polypropylene double-needled sutures are used to suture the valve edges together with the posterior commissural apex. All sutures are tied with knots outside the vein ( Fig. 61-1 ). Plication shortens the valve cusps to eliminate valve leaflet redundancy. For the divided anterior commissure, separate sutures are needed for each half before closing the venotomy. This kind of repair requires a precise initial venotomy. Otherwise, entering the vein may result in damage to the valve.




Figure 61-1


Kistner internal valvuloplasty. A , A longitudinal venotomy through the anterior commissure optimally exposes the valvular apparatus. Femoral vein internal valve repair is performed by applying multiple plicating sutures at each commissure through the valve cusps and the vein wall. B , Valve before and after repair. Sutures placed at each commissure tighten the angle and shorten the valve cusp.

( B , From Kistner RL: Surgical repair of a venous valve, Straub Clin Proc 34:41-43, 1968.)


As an alternative approach, a 1.5-cm supravalvular transverse incision can be performed 2.5 cm above the commissural apex. The valve cusps are sutured together at their free edges, starting from the more central portion of the vein toward the commissures to shorten about 20% of the leaflet length. A transverse venotomy can be converted into a T venotomy by extending the venotomy toward but not across the valve annulus, which increases exposure. Another incision is the “trapdoor” incision in which two partial transverse incisions are connected by a vertical incision through the anterior commissure. The choice of technique is dictated by surgeon preference with similar results reported for all approaches.


External Valvuloplasty


Valve leaflet attachment lines are brought together by placing external, partial-thickness, plicating sutures to decrease vein diameter in the absence of a venotomy. Interrupted sutures are initially placed at the commissural apex and then caudally placed over one fifth of the attachment line to narrow the commissural angle and decrease the vein diameter. Usually four to seven stitches are necessary at each commissural side until competence is noted by the strip test. A variation of this technique is limited anterior plication, in which only the anterior commissure is addressed by external valvuloplasty.


Angioscope-Assisted Valvuloplasty


An angioscope is used to identify valve attachment lines while external suturing is performed. The vein is surgically exposed, and the scope is inserted through a great saphenous vein tributary or a venotomy proximal to the valve. If needed, a purse string may be placed around the scope entry site, because continuous irrigation with heparinized saline is required for optimal visualization. Suturing takes place from outside to inside the lumen and across each commissure encompassing the redundant free edges of the valve.


Transcommissural Valvuloplasty


Sutures are externally placed in a blind fashion without a venotomy. The first sutures lie at the commissural apex and are kept shallow. The lower sutures are deepened farther into the vein to encompass the cusp edges, like in angioscopic-assisted valvuloplasty. This closes the valve attachment angle and tightens the valve cusps.


External Banding Valvuloplasty


Some veins are incompetent because their diameter exceeds valve leaflet length, and a reduction in diameter may restore competence by allowing the cusps to meet. A 2- to 3-cm-long sleeve of polytetrafluoroethylene or polyester is wrapped around the valve, tightened to the desired diameter until competence is achieved, sutured longitudinally, and then secured to the adventitia. This technique can be used to reinforce other valvuloplasties if the vein appears to be particularly dilated.


Autologous Neovalve Construction


Postthrombotic valves have been reconstructed without implantation of foreign material. Valves can be created de novo in the shape of semilunar cusps made by trimming the adventitia and part of the media of the great saphenous vein or one of its tributaries. The nonintimal surface is then sewn in place and directed toward the lumen to decrease the risk of thrombosis. Alternatively, the great saphenous vein or a tributary of a deep vein is obliquely transected near its origin, and its stump is invaginated to be secured with a stitch to the opposite wall of the deep vein and thus create a pseudoneovalve. The fibrous tissues of postthrombotic veins have also been used to create de novo, in situ neovalves, with the femoral vein used for most repairs. In brief, the femoral vein is exposed and the valve reconstruction site is determined based on preoperative and intraoperative assessment. The venotomy can be longitudinal, T -shaped, or transverse. Dissection of the valve flap is initiated after endovenectomy using an ophthalmic scalpel or microsurgical scissors to lift a flap of intimal tissue. The depth of the valve is determined empirically so that the flap is sufficiently wide to occlude the lumen. Either a bicuspid or monocuspid valve can be created depending on the circumferential distribution of thrombotic thickening. The free edge of the flap near the attachment of neocommissure to the vein wall is secured in a semi-open position by applying 7-0 polypropylene sutures to fix it to the vein wall. The venotomy is closed, the vessel opened, and the flap assessed.


Vein Segment Transposition


In the presence of a great saphenous vein or profunda femoral vein segment with a competent valve, the incompetent common femoral vein can be divided distal from the incompetent valve and anastomosed end-to-end or end-to-side to the adjacent valve-bearing vein. The profunda femoral vein is preferred because of the higher likelihood of late incompetence of the proximal valve of the great saphenous vein.


After performing a standard groin incision, the common femoral vein and its tributaries are dissected over a 10-cm length. Venous clamps are applied, and the femoral vein is transected at its confluence with the common femoral vein. The distal stump of the femoral vein is anastomosed to the anterior surface of the profunda femoral vein; alternatively, an end-to-end anastomosis is performed between the femoral vein and the first profunda femoral vein branch. An incompetent profunda femoral vein can be sewn to a competent great saphenous vein in similar fashion.


Vein Valve Transplantation


A vein segment containing one or more competent valves, characteristically the axillary or brachial vein, is interposed within an femoral vein or popliteal vein segment whose valves are destroyed or unrepairable by conventional valvuloplasty techniques. A two-team approach significantly reduces operative time. The recipient vein is initially exposed ( Fig. 61-2 , A ), followed by exposure of the donor vein. With the contralateral arm abducted and externally rotated, an 8- to 10-cm-long longitudinal incision is performed in the axilla parallel to the neurovascular bundle. The axillary vein is exposed, its branches are dissected and ligated, and the anterior wall is marked longitudinally with a marking pen to help prevent torsion at the time of transposition. Before harvesting the axillary vein, valve competence should be confirmed by duplex imaging or a strip test. Up to 40% of axillary vein valves may be incompetent but amenable to transcommissural or internal valvuloplasty. However, identifying a more proximal or distal segment containing a competent valve or harvesting the ipsilateral axillary vein is preferred.


Mar 13, 2019 | Posted by in VASCULAR SURGERY | Comments Off on Surgical Treatment of Lower Extremity Deep and Perforator Vein Incompetence
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