By Roberto Sacilotto
In the past decade, the most significant change in the treatment of critical limb ischaemia has been the shift from bypass surgery to less invasive endovascular procedures as first choice revascularisation interventions. In the initial reports of percutaneous transluminal angioplasty use for critical limb ischaemia patients, relatively poor rates of secondary patency were frequently observed but with satisfactory values of limb salvage. Recent investigations for infrapopliteal angioplasty have shown increasingly better results in patency and limb salvage.
However, as reported by Giles et al (J Vasc Surg 2008;48:128-36)1, endovascular treatment in TASC D lesions is associated with freedom from restenosis, reintervention, or amputation in only 14% of patients at one-year follow-up.
In addition, Conrad et al (J Vasc Surg 2009;50:799-805)2 conducted an analysis of infrapopliteal balloon angioplasty and found that TASC D was an independent variable associated with primary patency failure. This finding is in agreement with results of our previous study, which demonstrated poor results for angioplasty treatment of TASC D lesions (Vasc Endovasc Surg 2010;44:625-32)3. In addition, the BASIL (Bypass versus angioplasty in severe ischaemia of the leg) trial reported better results for limb salvage and long-term survival in patients treated with bypass graft surgery4. On this basis, patients with extensive atherosclerotic disease should be treated with vein bypass surgery in the presence of acceptable inflow/ outflow arteries, appropriate conduit, and good clinical status.
Patients with diabetes mellitus and critical limb ischaemia generally show extensive tibial and peroneal occlusion, with the foot arteries spared from atherosclerotic disease. This condition makes the dorsalis pedis and common plantar targets for distal revascularisation5,6. These major arteries are sometimes occluded, but the branches (tarsal and plantar arteries) are patent and serve as runoffs for a bypass graft5,6,7. Most patients who require a bypass to perimalleolar arteries have extensive atherosclerotic disease.
In conclusion, despite technical improvements in endovascular therapy, bypass graft surgery still plays a role in modern treatment of critical limb ischaemia.
In addition, these techniques should continue to be taught in vascular training programmes to ensure they can be used as an alternative to limb salvage when angioplasty fails.
Long-term follow-up of foot branch bypass procedures demonstrated good results for limb salvage and are an acceptable surgical option for patients with extensive atherosclerotic disease (TASC D lesions) as a last attempt at limb preservation8,9.
Some details of our techniques are described below:
Duplex ultrasound is used preoperatively to evaluate the quality, calibre, and phlebitis signs of the conduits, with the intention of using the best vein segments.
After selection of the distal artery, the donor artery and conduits are dissected. We preferentially use removed and non-reversed great saphenous vein. A Mills valvulotome is applied after the proximal anastomosis. We do not perform in situ saphenous vein bypass, and non-reversed vein is generally chosen to match the calibre between the conduit and inflow/outflow arteries. A single-segment arm vein is used when great saphenous vein is unusable or when composite grafts are necessary.
Tunnels are preferably placed in the anatomic course with the intention of preventing eventual graft wound dehiscence. All patients receive 5,000 IU of non-fractionated heparin intravenously before the anastomosis.
All procedures are conducted using loupe magnification.
All distal anastomoses are performed using non-interrupted 7–0 polypropylene sutures; for distal vessel haemostatic control, a loop suture is placed, using humid regular catgut. Before the distal anastomosis, in most cases, the pedal branches are opened and tested with saline infusion using a 20-gauge intravenous cannula passed through the lumen of the artery.
After discharge, all patients are followed up in ambulatory visits. In the early postoperative period, patients are monitored weekly and ambulatory visits are scheduled according to the evolution of wound healing.
Graft patency is checked by pulse palpation and continuous Doppler wave evaluation. Patients are also assessed with duplex ultrasound, at regular intervals of one, three and six months. Arteriography was performed if any abnormality was detected. These evaluations are in accord with the TASC guidelines10.
Roberto Sacilotto is a professor, São Paulo State University, chief, Department of Vascular Surgery, Hospital do Servidor Publico Estadual de São Paulo, São Paulo, Brazil
References
1. Giles KA, Pomposelli FB, Spence TL, Hamdan AD, Blattman SB, Panossian H, et al. Infrapopliteal angioplasty for critical limb ischemia: relation of TransAtlantic InterSociety Consensus class to outcome in 176 limbs. J Vasc Surg 2008; 48:128-36.
2. Conrad MF, Kang J, Cambria RP, Brewster DC, Watkins MT, Kwolek CJ, et al. Infrapopliteal balloon angioplasty for the treatment of chronic occlusive disease. J Vasc Surg 2009; 50:799-805.
3. Casella IB, Brochado-Neto FC, Sandri GA, Kalaf MJ, Godoy MR, Sacilotto R, et al. Outcome analysis of infrapopliteal percutaneous transluminal angioplasty and bypass graft surgery with nonreversed saphenous vein for individuals with critical limb ischemia. Vasc Endo- vasc Surg 2010; 44:625-32.
4. Bradbury AW, Adam DJ, Bell J, Forbes JF, Fowkes FG, Gillespie I, et al. Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL) trial: analysis of amputation free and overall survival by treatment received. J Vasc Surg 2010; 51 (5 Suppl):18S-31S
5. Baird RJ, Tutassaura H, Miyagishima RT. Saphenous vein bypass grafts to the arteries of the ankle and foot. Ann Surg 1970; 172: 1059-63.
6. Ascer E,Veith FJ,Gupta SK. Bypasses to plantararteriesandothertibial branches: an extended approach to limb salvage. J Vasc Surg 1988;8:434-41.
7. Andros G, Harris RW, Salles-Cunha SX, Dulawa LB, Oblath RW, ApyanRL. Bypass grafts to the ankle and foot. J Vasc Surg 1988; 7:785-94.
8. Brochado Neto FC, Cury MV, Costa VS, Casella IB, Matielo MF, Nakamura ET, et al. Inframalleolar bypass grafts for limb salvage. Eur J Vasc Endovasc Surg 2010; 40:747-53.
9. Brochado-Neto, F C PhD, Cury M V M , MD, Bonadiman,S S T MD, Matielo,M F PhD, Tiossi,S R MD, Godoy M R, MD, Nakano,K MD, and Sacilotto, R PhD, São Paulo, SP, Brazil Vein bypasses to branches of pedal arteries. J Vasc Surg 2012; 55:746-52.
10. Norgren L, Hiatt WR, Dormandy JA, Nehler MR, Harris KA, Fowkes FG, et al. Inter-Society Consensus for the Management of peripheral Arterial Disease (TASC II). Eur J Vasc Endovasc Surg 2007; 33 (Suppl 1):S1-75.
