Revascularization to an isolated (“blind”) popliteal artery segment: A viable procedure for critical limb ischemia

[Surgical therapy of peripheral arterial occlusive disease]

The surgical treatment of peripheral arterial occlusive disease focuses not only on the direct restoration of the femoral bifurcation but also on the peripheral bypass, especially in the case of chronic amputation-threatening ischemia. Comprehensive imaging is indispensable for planning surgical therapy. The local reconstruction of the femoral bifurcation offers very good long-term results and can be easily combined with endovascular methods. The peripheral bypass is the central pillar of surgical therapy, especially in CLTI. Autologous vein should always be the first-choice material. It delivers good long-term results in every position. Prosthetic material is only used if there is no vein and should be combined with autologous veins in the crural and pedal area if possible. The technical limit for a bypass system lies in the pedal arteries and their branches. These methods can be combined with upstream and downstream endovascular interventions in the form of a hybrid intervention. Surgical and endovascular interventions are to be considered as complementary.

Isolated femoral artery revascularisation with or without iliac inflow improvement - a less invasive surgical option in critical limb ischemia

Background: Isolated femoral artery revascularisation (iFAR) represents a well-established surgical method in the treatment of peripheral arterial disease (PAD) involving common femoral artery disease. Data for iFAR in multilevel PAD are inconsistent, particularly in patients with critical limb ischemia (CLI). The aim of the study was to evaluate the outcome of iFAR in CLI regarding major amputation and reintervention and to identify associated risk factors for this outcome. Patients and methods: The data used have been derived from the German Registry of Firstline Treatment in Critical Limb Ischemia (CRITISCH). A total of 1200 patients were enrolled in 27 vascular centres. This sub-analysis included patients, which were treated with iFAR with/without concomitant iliac intervention. For detection of risk factors for the combined endpoint of major amputation and/or reintervention, selection of variables for multiple regression was conducted using stepwise forward/backward selection by Akaike's information criterion. Results: 95 patients were included (mean age: 72 years ± 10.82; 64.2% male). Of those, 32 (33.7%) participants reached the combined endpoint. Risk factor analysis revealed continued tobacco use (odds ratio [OR] 2.316, confidence interval [CI] 0.832-6.674), TASC D-lesion (OR: 2.293, CI: 0.869-6.261) and previous vascular intervention in the trial leg (OR: 2.720, CI: 1.037-7.381) to be associated with reaching the combined endpoint. Conclusions: iFAR provides a reasonable, surgical option to treat CLI. Lesion length (TASC D) seems to have a negative impact on outcome. Further research is required to better define the future role of iFAR for combined femoro-popliteal lesions in CLI - best in terms of a randomised controlled trial.

Surgical revascularization and reconstruction procedures in diabetic foot ulceration

This article summarizes surgical procedures for preservation of the foot in diabetic patients with peripheral artery disease. Distal bypass surgery performed to perigeniculate arteries and to an isolated 'blind' popliteal segment with visible collaterals can be performed with limb salvage rates close to what can be achieved with standard bypass to crural arteries. This is also the case when performing bypass to the dorsalis pedis artery. Bypass to the medial or lateral plantar artery or to the lateral tarsal artery is associated with a relatively high rate of early occlusion, but in the patients who have persistently open grafts, limb salvage is common. The use of an arteriovenous fistula as an adjunct to distal bypass surgery does not improve prognosis. Venous arterialization, either creating retrograde perfusion of the superficial or of the deep veins of the foot has been successful in several cases although it is difficult to predict which patients will benefit. Reconstructive surgery is often performed in a multidisciplinary team including plastic surgeons. In patients with need of more extensive cover of defects, the transplant of muscular or fasciocutaneous free flaps has provided good results in the few centres that have applied this technique. This procedure can be combined with a revascularization in the same session or at a later stage. A majority of the described techniques can be implemented in most vascular centres and they should be considered in complicated cases when standard methods of revascularization and reconstruction do not suffice.

Global Vascular Guidelines on the Management of Chronic Limb-Threatening Ischemia

GUIDELINE SUMMARY

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Global vascular guidelines on the management of chronic limb-threatening ischemia

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

The Impact of Geniculate Artery Collateral Circulation on Lower Limb Salvage Rates in Injured Patients

BACKGROUND

This study aimed to determine the association between geniculate artery flow on admission computed tomography (CT) angiography and limb salvage outcomes in patients with lower extremity arterial injury.

METHODS

All injured patients at a level I trauma center with CT angiogram (CTA) confirmed limited or no flow to the tibial vessels were included. Demographics, injury severity score (ISS), mechanism of injury, physiological parameters, the presence of geniculate artery collateral circulation (superior medial, superior lateral, medial, inferior medial, inferior lateral), and 30-day limb salvage outcome were recorded. Statistical analysis was completed using descriptive statistics and the chi-squared tests.

RESULTS

From 2009 to 2012, a total of 84 patients with lower extremity arterial injury underwent diagnostic evaluation with CTA on admission that confirmed limited or no flow to the tibial vessels. A total of 10 patients (12%) underwent amputation. Primary amputation was performed in 3 (4%) patients, and secondary amputation was performed in 7 (8%) patients. There was no difference in age, gender, ISS, extremity abbreviated injury score, mechanism of injury, admission systolic blood pressure, heart rate, respiratory rate, transfusion volume, or type of vascular interventions between patients who had successful limb salvage and those who received an amputation. The number of patent geniculate arterial vessels was inversely associated with amputation with 3.3 patent geniculate arteries in the limb salvage group compared to 2.1 in the amputation group (P < 0.05). The 2 geniculate artery vessels that were significantly associated with limb salvage were the superior lateral geniculate and the inferior medial geniculate arteries (P < 0.05).

CONCLUSIONS

Geniculate collateral circulation may have an important role in limb salvage after lower extremity vascular injury. The geniculate arteries that are associated with the highest rates of limb salvage appear to be the superior lateral geniculate and the inferior medical geniculate artery.

An uncommon clinical presentation of acute limb ischemia: underscoring the role of perigenicular collaterals

We present a case of atypical acute limb ischemia in a non-diabetic patient, with ankle-brachial pressure index of 0.6 and rest pain localized exclusively over the gastrocnemius muscle, sparing the foot. This uncommon presentation was attributed to an impaired perigenicular collateral network. Thrombolysis restored adequate perfusion only temporarily and was followed by thromboembolectomy. The ischemia presentation in our case underscores the importance of the adequacy of the perigeniculate collateral network for the perfusion of the tibial muscles and, especially, the gastrocnemius muscle.

Sural Artery Bypass in Buerger's Disease: Report of a Case

A 72 year-old man was admitted to the hospital to receive treatment for resting pain and an ulcer, which had developed on an amputation stump, 4 months after he had undergone a thrombectomy, below-the-knee popliteal-dorsal pedis artery bypass of his left leg, and digital amputation of his 2nd toe. Angiography demonstrated diffuse arterial and bypass occlusion in his left leg that did not include a sural artery, which was the main collateral. Therefore, the patient underwent reversed saphenous vein bypass from the common femoral artery to the medial sural artery. His leg pain disappeared, and the ulcer healed promptly.

Subintimal angioplasty for below-the-ankle arterial occlusions in diabetic patients with chronic critical limb ischemia

PURPOSE

To assess the feasibility and efficacy of subintimal angioplasty (SA) in the treatment of below-the-ankle arterial occlusion in diabetic patients with chronic critical limb ischemia (CLI).

METHODS

SA was applied in 37 diabetic patients (24 men; mean age 70.9+/-8.5 years, range 52-88) with chronic CLI and occlusive disease of the dorsalis pedis artery (DPA) and/or plantar artery (PA) but were poor candidates for intraluminal angioplasty or bypass surgery. Tissue loss was present in 31 (54.4%) of 57 afflicted limbs, and rest pain was reported in 51 (89.5%) limbs. SA was performed to create continuous arterial flow to the foot for limb salvage. The clinical symptoms, DPA or PA pulse volume scores, and ankle-brachial index (ABI) were compared before and after SA. Wound healing, amputation, and restenosis of target vessels were also evaluated at follow-up. Kaplan-Meier curves were constructed to evaluate limb salvage, survival, and freedom from amputation.

RESULTS

Below-the-ankle SA was performed successfully in 55 (83.3%) of 66 arteries in 57 limbs. Median pulse volume scores and ABIs were 0.33+/-0.55 and 0.31+/-0.19 before SA and 2.04+/-1.05 and 0.80+/-0.14 after SA, respectively (p<0.0001 for both). The 30-day mortality was 2.7%. Median follow-up was 9.1+/-6.1 months (range 1-18). Major complications occurred in 1 (2.7%) patient and minor complications in 3 (8.1%). Twelve months after SA, Kaplan-Meier analysis showed that the limb salvage rate was 94.6%, the freedom from amputation was 89.2%, and the survival rate was 97.3%.

CONCLUSION

SA of the dorsalis pedis artery and/or plantar artery is a useful technique for lower limb salvage in diabetic patients with chronic CLI who are not candidates for bypass surgery.