Critical Limb Ischemia
Extreme revascularizations
Criteria for critical ischemia in 2016
Joël Constans (France)
It is fundamental to confirm critical limb ischemia using objective criteria because the typical classifications of critical limb ischemia are mostly based on absolute ankle pressure, which is associated with an important number of false negatives, thus excluding a relevant number of critical limb ischemia patients. Today, toe pressure (or the TcPo2) is a noninvasive first-choice technique to confirm critical limb ischemia objectively. As the definition of critical limb ischemia varies, caution should be used when regarding the clinical trial data. Clear and conclusive standardized definitions are needed.
Interest in angiosome revascularization for the healing of arterial trophic problems in patients with femoral-peroneal bypass
Jean-Baptiste Ricco (France)
Ricco presented a retrospective review study that compared direct revascularization with indirect revascularization according to foot angiosomes and the runoff score of the peroneal branches (anterior perforating and lateral calcaneal branches) using a propensity score analysis. Overall limb salvage at 2 years was 69%, amputation-free survival was 56%, limb salvage at 3 years in patients with direct revascularization was 70.6}5% compared with 68.5}6% in patients with indirect revascularization, no significant difference in wound healing (P=0.42), and limb salvage at 3 years in patients with two peroneal branches open was 80}5% compared with 60.8}5% in patients with one open branch and a significant difference in wound healing (P=0.001). In a multivariate analysis with matched propensity scores, patency of both peroneal branches was a significant predictor for wound healing (OR, 2.7; 95% CI, 1.7-8.9), as was pedal arch patency, WIfi classification (wound infections and foot infection classification), diabetes, and renal failure, but not direct angiosome revascularization. There are many limitations to the angiosome concept, and the results suggest that patency of both peroneal branches provides better wound healing, irrespective of the primary wound angiosome. Direct revascularization of wound angiosomes using a peroneal bypass was possible in only half of the patients with tissue loss, and it did not seem to improve wound healing significantly (J Vasc Surg. 2015;61[6 suppl 1]:37S).
Extreme bypasses
Sébastien Deglise (France)
Even if endovascular techniques are currently considered the first-line therapeutic modality for patients with critical limb ischemia, a distal bypass is still relevant. Several issues should be considered for a successful open surgery, with the conduit as a key point. Deglise stressed the relevance of a correct preoperative mapping of the available veins (ie, the diameter [>3 mm], lumen, wall, and path) and a very gentle surgical technique to adequately preserve the harvested vein(s). As there is no adequate great saphenous vein in 20% to 45% of the cases, arm veins (even spliced) can be used safely, with good results. Anticoagulation, lymphatic drainage, and frequent clinical and imaging follow-up visits after the surgery are important. In conclusion, a good selection of patients is obligatory (arterial and venous mapping; comorbidities); distal bypasses still have a place as they are complementary to endovascular techniques; and vascular surgery plans have to take these specific surgical procedures into account.
Therapeutic angiogenesis and other therapeutic progress
Marie-Antoinette Sevestre-Pietri (France)
Therapeutic angiogenesis is a process that aims to induce the formation of new vessels in order to increase the amount of blood in the tissues. There are two types of therapeutic angiogenesis–cellular therapy and gene therapy. Cellular therapy uses endothelial stem cells from bone marrow, blood, or mesenchymal stem cells. These stem cells are placed in the ischemic tissues to induce the formation of new vessels. Gene therapy delivers a proangiogenic factor to ischemic tissues as either recombinant proteins or viruses with the replication sequence replaced by the gene of interest. In the initial experimental and nonrandomized clinical studies on peripheral arterial disease, therapeutic angiogenesis produced promising results. However, the first randomized clinical trials performed in claudicant patients failed to demonstrate a clear benefit of this alternative therapy, pointing to the complexity of the angiogenic process. Retrospectively, since angiogenesis occurs mainly in ischemic tissues, it is quite comprehensible that, in claudicant patients, it could not work per se as the tissues do not have ischemia at rest. The Talisman study (Mol Ther. 2008;16(5):972- 978; Lancet. 2011;377:1929-1937), the first randomized controlled trial on critical limb ischemia for no-option patients, showed no difference regarding amputation rates. Sevestre-Pietri concluded that, due to the complex mechanisms involved in angiogenesis, there is still a lot to learn before achieving an effective and stable therapeutic angiogenesis.
Infragenicular PAOD in the Southern Mediterranean: towards an optimal endovascular strategy
Emad Hussein (Egypt)
Hussein presented options for an optimal endovascular strategy in infragenicular peripheral arterial occlusive disease, especially in patients with critical limb ischemia. This pattern of disease is more prevalent than proximal disease, and it is often associated with diabetes. The possible treatment options include transluminal/ subintimal percutaneous angioplasty; cutting and drug-coated balloons; baremetal, drug-eluting, and bioabsorbable stents. New devices have a role in heavy calcifications, lesions lengths >10 cm, and ulcerated plaques. Patients with critical limb ischemia always need a multidisciplinary approach, but, in most cases, Hussein prefers the “endo first approach.” For patients with critical limb ischemia, open surgery has been partially replaced by endovascular procedures, but if endovascular attempts fail or are not indicated, open surgery may follow.
