CLI AND TREATMENTS FOR LIMB SALVAGE

6.5.1 Revascularization Procedures

In addition to life style modifications, an optimal medical treatment, including at least one antiplatelet regimen and a meticulous control of the cardiovascular risk factors, the lower limb revascularization is an essential step by treating CLI patients. There are two different way to improve distal blood perfusion: the surgical and the endovascular approach. The aim of these procedures is to improve ischemic rest pain or to allow an ischelmic ulcer to heal, finally avoiding major amputation.

Aortoiliac disease is also called inflow disease. Infrainguinal disease is also called outflow disease. Among patients with both inflow and outflow (infrainguinal) disease, the ACC/AHA guidelines as well as the TASC II guidelines recommended that inflow lesions be addressed first, whether surgery or percutaneous intervention is performed (2, 3). After this has been accomplished, revascularization of outflow disease is warranted if there is persistent infection, ischemic ulcers, or gangrenous lesions, and the ABI remains less than 0.8 (261).

Until recently, the surgical options (e.g. femoropopliteal or femorotibial bypasses) were the only available approach in order to improve foot perfusion. These kind of limb-saving interventions are associated with an increased risk of morbidity and mortality, especially in this particular CLI patients’

subset (i.e., elderly and sick patients), and despite a relatively disappointing long-term patency rate of the performed intervention, surgery was very often proposed as first line treatment (2).

Accordingly, tha BASIL trial has showed that in 450 patients presenting with a CLI due to an infra-inguinal arterial disease who were eligible for either procedure (surgical or endovascular), at 30 days, there was no difference in mortality between the two groups, but surgery was associated with a significantly higher rate of morbidity (57 versus 41%). Furthermore, there was no difference in the primary end point (survival without amputation) at one year (71% with endovascular versus 68% with surgery) and three years (52% versus 57%), with only a higher rate of reintervention in the

endovasculart group (26% versus 18%) (262).

Concerning the percutaneous approaches, it is since more the thirty years that vascular

specialists have tried to decrease the aggressiveness of revascularization procedures, finally resulting in what is nowadays called the endovascular domain (131-133). Since several years, the

endovascular approach is nowadays proposed as the first revascularization procedure to attempt in many different clinical scenarios. Due to the variety and complexity of these different techniques, often

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a multidisciplinary approach involving all the different vascular specialists is required, in order to tailor the revascularization procedure to each single case.

In general the degree of aggressiveness should be less for claudicant patients, than for those presenting with acute or criticial limb ischelmia, where more complex, thus more risky, procedures may be attempted.

Firstly described in 1997, the endovascular approach has emerged as an attractive alternative to surgery in CLI patients (242). In the first period of the endovascular experience in case of CLI, BTK or infra-popliteal interventions were always associated with some type of femoropopliteal

revascularization procedure. The rational of combining a femoropopliteal intervention with BTK interventions was that of improving the distal run-off, thus potentially improving the long-term patency of the femoropopliteal intervention. It is only very recently, that special attentions were given to the infra-popliteal region and the isolated BTK interventions.

This “new” isolated BTK disease is often observed in very elderly patients (i.e., >80 years old) presenting with longstading diabetes. Accordingly, CLI secondary to an isolated BTK problem is associated with normal or near-normal inflow (i.e., disease-free ilio-femoro-popliteal axes) and a very severly diseased BTK region, associating multiple long chronic total occlusions of one or more of the infra-popliteal arteries.

The introduction of BTK dedicated materials and the development of BTK dedicated revascularization techniques has broadened the type of patients who may benefit from such a revascularization procedure, but most importantly has allowed a significant improvement in the technical and the clinical outcomes of these high risk patients (140, 263). However, despite the actual technical success rate (i.e., final angiographic result with <50% residual stenosis) is very high (up to 90%) and the complication rate is very low (< 5%), the mid-longterm patency rate remains quite low (12 months primary patency rate of ≈ 50%).

Indeed, if a few months patent vessel is often sufficient to heal simple or small ulcers, more complex trophic lesions, as an infected ulcer or in the presence large necrotic zones, require more time before completely heal.

Accordingly, an early vessel restenosis or reocclusion will jeopardize the ulcer healing process, finally increasing the patient’s morbidity. For these reasons, a better patency rate at 12 months has become a priority also in CLI patients presenting with an isolated BTK disease. Thanks to the vast

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armamentarium of devices and techniques at disposal of every endovascular specialist and especially thanks to clinical data reported in the literature, it is now admitted that infra-popliteal endovascular interventions are associated with an acceptable primary and secondary patency rate, an acceptable rate of ulcer healing and a significant decrease in the minor and major amputations rates (263).

For all these reasons, in many centers, an endovascular revascularization attempt in case of CLI is always proposed, especially in case of an amputation scheduled, and this also in very elderly patients presenting with very complexe BTK diseases. However, despite, these considerations approximatively 200.000 new amputations are yearly performed in the United States, with almost half of them performed without neither an adequate vascular evaluation nor a revascularization attempt.

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