Open Deep Venous Arterialization for No-Option Chronic Limb-Threatening Ischemia: A Variable and Adaptable Technique

Abstract

Background: Patients with no-option chronic limb-threatening ischemia (NoCLTI), lacking suitable distal arteries for conventional revascularization, face major limb amputation. The 1-year mortality rate after major amputation is 48.3%, increasing to 70.9% in 3 years. Open deep venous arterialization (DVA) offers a promising alternative for limb salvage, achievable through open, endovascular, or hybrid approaches. We aim to provide a comprehensive, step-by-step guide to performing open DVA in NoCLTI patients, addressing preoperative and postoperative considerations as well as the technical details of the procedure. Methods: Patient selection for open DVA focuses on individuals with NoCLTI at high risk for amputation. Preoperative assessments include evaluating risk factors, determining limb threat severity using the Wound, Ischemia, and foot Infection (WIfI) score, and mapping anatomical patterns via the Global Limb Anatomic Staging System (GLASS). The procedure involves identifying the target artery using Doppler ultrasound, performing microdissection to expose the artery and vein, ligating proximal vein branches, and creating a side-to-side anastomosis. Venous valves are disrupted with a valvulotome to allow antegrade flow. A proximal bypass graft may be applied if necessary. Results: Postoperatively, patients are monitored for 2–4 days with frequent Doppler assessments. Anticoagulation therapy begins with a heparin drip, transitioning to oral agents and/or dual antiplatelet therapy. Wound care includes deferred debridement for 2–4 weeks and may involve negative-pressure therapy. Follow-up involves weekly visits for the first month, and then at 3 months, and every 6 months thereafter, with surveillance using transcutaneous oxygen measurement, the toe–brachial index, and arterial duplex ultrasound. Conclusions: Open DVA represents a viable limb salvage option for patients with NoCLTI, potentially avoiding major amputations and improving quality of life. Success depends on careful patient selection, a meticulous surgical technique, and comprehensive postoperative care.

1. Introduction

Peripheral arterial disease (PAD) affects 202 million people worldwide, significantly contributing to morbidity and mortality [1]. Chronic limb-threatening ischemia (CLTI) is the most severe manifestation of PAD, associated with a high risk of major amputation and substantial healthcare costs [2]. The Italian CLIMATE registry, which included 2399 patients treated for CLTI, reported an overall mortality rate of 3.1% in 30 days and 13.5% in 1 year [3]. The lifetime cost per patient for major amputation is approximately USD 509,275, whereas limb preservation costs around USD 163,282 [4]. The 1-year mortality rate after major amputation is 48.3%, increasing to 70.9% at 3 years [5,6]. For patients with no-option CLTI (NoCLTI), where conventional revascularization is not feasible, due to the lack of viable distal targets, deep venous arterialization (DVA) provides a promising alternative to major amputation [7,8,9,10,11,12,13,14]. DVA can be accomplished through open, endovascular, or hybrid approaches [7,15,16]. This manuscript provides a comprehensive, step-by-step guide to performing open DVA in NoCLTI patients, addressing preoperative and postoperative considerations as well as the technical details of the procedure.

2. Patient Selection and Preoperative Assessment

The Society for Vascular Surgery (SVS) recommends a comprehensive approach to managing CLTI that incorporates patient risk factors, the severity of limb threat assessed using the WIfI score (Wound, Ischemia, and foot Infection), and the anatomical patterns of the disease evaluated with the global anatomic staging system (GLASS) [17]. This approach helps ensure that each patient receives the most appropriate treatment based on these crucial factors.

Candidates for open DVA are patients with NoCLTI who lack suitable distal arteries for revascularization, are facing major limb amputation, and have rest pain and/or an ischemic wound (Figure 1). After thoroughly evaluating the patient’s risk factors and determining their WIfI and GLASS stages, it is important to have a well-informed discussion about the procedure and its potential outcomes. This conversation should ensure the patient fully understands the plan, confirms their commitment to the perioperative care strategy, and confirms they have adequate social support in place. Preoperative digital subtraction angiography to assess the arterial anatomy, and venous mapping via ultrasound to evaluate the adequacy of the available vein conduit are critical steps in the planning process.

3. Exclusion Criteria

Active foot infection;

Previous extensive deep vein thrombosis with residual sequelae;

Massive tissue loss of the forefoot that extends proximally;

Compromised cardiopulmonary status;

Prolonged immobility status.

4. Surgical Setup and Anesthesia

The procedure is performed under general anesthesia, with prophylactic antibiotics administered to prevent infection. Prolonged antibiotic coverage may be considered on a case-by-case basis after consultation with an infectious disease specialist. The operating room should be prepared and equipped with microsurgical tools, and a microscope should be available if needed, particularly when the target vessels are less than 1.5 mm in diameter. Based on preoperative imaging, the surgeon should develop a plan to identify the best target vessels (artery and vein) for creating the arteriovenous fistula (AVF), aiming to minimize tissue dissection and associated trauma.

5. Surgical Technique

5.1. Artery Identification

The posterior tibial (PT) and dorsalis pedis (DP) arteries are the most commonly used arteries for the procedure, with pedal artery branches serving as alternative targets. A handheld Doppler device is used to assess the target artery, and the skin is marked accordingly.

5.2. Incision and Microdissection

A 2–3 cm incision is made over the marked artery using a size 15 blade. Microdissection follows to expose the target artery and corresponding adjacent veins. Care is taken to avoid excessive manipulation of the vessels during dissection.

5.3. Vessel Control and Vein Branch Ligation

After dissecting the target artery and vein, the proximal branches of the corresponding adjacent vein are typically ligated using 4-0 silk ties to minimize the early steal phenomenon after AVF creation. The target artery and vein are then controlled both proximally and distally using micro-vascular clips.

5.4. AVF Creation and Valvulotomy

After systemic heparinization (targeting an activated clotting time (ACT) > 250), a longitudinal arteriotomy and venotomy are performed using a beaver blade (Figure 2). A 1.0–1.5 mm coronary dilator is initially introduced to estimate the proximity of the nearest venous pedal valve. A valvulotome is then used to disrupt the venous valve, and this process is repeated until the coronary dilator can reach the distal aspect of the foot, typically corresponding with the middle metatarsal bones. Occasionally, valvotomy can be assisted under fluoroscopic guidance using a buddy wire such as glidewire. After the venous valves are disrupted, the AVF is created by performing a side-to-side anastomosis between the target artery and the corresponding vein. An 8-0 Prolene suture is typically used to create the anastomosis, ensuring a tension-free connection. From our experience, when the vein size is less than 2 mm, we use a vein patch to increase the luminal diameter of the AVF. A proximal conventional bypass is constructed using either a prosthetic or biological graft. The graft is then anastomosed in an end-to-side fashion to the venous patch or directly to the arteriovenous fistula (AVF) using an 8-0 Prolene suture.

5.5. Completion Angiogram and Wound Closure

Upon completing the AVF, a completion angiogram is performed to assess the patency of the AVF, confirm flow into the forefoot venous outflow, and identify proximal vein branches, which are then ligated to prevent early steal. The wound is then meticulously closed. Care is taken to avoid placing any undue pressure on the newly created AVF, as this could result in compression and subsequent thrombosis. Adequate hemostasis is confirmed, and the surgical site is closed using vertical mattress sutures in an interrupted fashion with a 3-0 nylon suture to minimize complications such as infection or skin necrosis.

6. Postoperative Management

The patient is monitored closely in the hospital for 2–4 days postoperatively, focusing on Doppler signals over the AVF and the foot to ensure AVF patency. In our practice, we mark clearly distinct points corresponding to the bypass, AVF, and distal arterial outflow sites, and frequently assess the Doppler signal at each location. It is important not to perform ankle–brachial index (ABI) measurements over the AVF, to avoid shutting off the AVF or disturbing it.

The patient is initiated on anticoagulation therapy, starting with a heparin drip for 24 to 36 h postoperatively, followed by a transition to oral anticoagulants, and/or dual antiplatelet therapy depending on the patient’s tolerance and comorbidities. Pain management and wound care protocols are implemented to ensure proper healing, with sharp debridement of the wound deferred for at least 2 to 4 weeks to prevent bleeding and avoid premature tissue removal. Negative-pressure wound therapy using a wound vacuum device may be considered. Occasionally, an ankle brace is used as an adjunct to minimize tension on joint areas and reduce friction over the surgical site caused by frequent movement while the patient is in bed.

Follow-Up

Regular follow-up is critical to monitor the patient’s recovery and detect any complications early. Follow-up visits are scheduled weekly for the first month, followed by visits at 3 months, and then every 6 months thereafter. Surveillance using transcutaneous oxygen measurement (TcPO2), the toe–brachial index (TBI), and arterial duplex ultrasound is essential for evaluating adequate oxygen delivery, wound healing capacity, and the patency of both the bypass and AVF. The healing process can take several months, requiring close coordination with a wound care specialist and/or podiatrist. Patients should be informed that digital ischemia may worsen, and the primary goal of DVA is to avoid major amputations.

At our institution, we performed open DVA procedures on 15 patients with no-option CLTI, including one patient who underwent bilateral surgeries. Over a median follow-up period of 119 days (range: 52–742 days), minor amputations were performed on 7 out of 15 limbs, while major amputations were required for 5 out of 15 limbs. Additionally, complete wound healing was achieved in 5 out of 15 limbs (Supplemental Table S1 shows detailed patients’ outcomes).

7. Key Points for Successful DVA

• Use the most distal satisfactory artery to minimize postoperative edema and pain. The PT artery is preferred in cases of extensive forefoot tissue loss.
• Careful microdissection of the target vessels is crucial to maintain their viability and avoid injury.
• A meticulous valvulotomy of the distal vein is necessary to ensure adequate antegrade flow, with care taken to avoid vein injury or rupture.
• Tension-free closure is essential to prevent thrombosis of the AVF.

8. Discussion

DVA is an emerging limb salvage technique for patients with NoCLTI, where conventional revascularization is not achievable, even with advanced techniques like retrograde puncture or re-entry systems, providing an alternative to major amputation in a population with limited options. DVA can also be performed using percutaneous and hybrid techniques. Hybrid DVA combines the open surgical technique to perform the bypass and the AVF with endovascular techniques to perform valvulotomy [15]. Percutaneous DVA, entirely endovascular, employs specialized systems like LimFlow, consisting of arterial and venous catheters, crossing devices, and self-expanding stent grafts, guided by imaging for precise execution [7]. The literature shows that DVA is associated with reduced amputation rates [18,19]. Our recent literature review found that open DVA is associated with a limb salvage rate of 30–100% at a follow-up of 1–24 months and a complete healed wound rate of 20–77.8% at 4.7–17 months. For percutaneous DVA, the limb salvage rate ranged from 60% to 100% at 6–13.5 months of follow-up, with complete wound healing rates between 23.8% and 78% within 4.8–13.5 months. Additionally, two studies reporting on hybrid DVA outcomes found limb salvage rates of 68.1% and 73% at 12 months, with complete wound healing rates of 44% and 54% at 7.6 and 12 months, respectively [20]. Wound healing remains a critical concern postoperatively, and the collaboration between the vascular surgeon and wound care specialist is vital for optimal outcomes [21]. Though DVA can restore perfusion to the foot, it does not consistently improve digital blood flow, and patients must be counseled accordingly [18]. The long-term durability of the procedure remains uncertain, as current evidence is predominantly drawn from short- to medium-term follow-ups.

In conclusion, open DVA is a valuable option for patients with NoCLTI, providing the potential for limb salvage and improved quality of life in patients with CLTI at high risk of major amputation.