Date Published: October 9, 2018
Publisher: Public Library of Science
Author(s): Chung Yeop Lee, Kyunghak Choi, Hyunwook Kwon, Gi-Young Ko, Youngjin Han, Tae-Won Kwon, Yong-Pil Cho, Jeffrey J. Rade.
We aimed to compare the clinical outcomes between endovascular treatment and inframalleolar bypass surgery for critical limb ischemia (CLI) in patients with thromboangiitis obliterans (TAO) and to assess the role of bypass surgery in the era of innovative endovascular treatment. Between January 2007 and December 2017, a total of 33 consecutive patients with the diagnosis of TAO presenting with CLI who underwent endovascular treatment (endovascular group, n = 22) or bypass surgery to the pedal or plantar vessels (bypass group, n = 11) were included and analyzed retrospectively. The primary endpoint was defined as a major amputation of the index limb, and the secondary endpoint was defined as graft occlusion, regardless of the number of subsequent procedures. In the bypass group, six patients (55%) had undergone previous failed endovascular procedures and/or arterial bypass surgery to the index limb before inframalleolar bypass, and two patients (18%) received microvascular flap reconstruction after bypass surgery. During the median follow-up period of 32 months (range 1–115 months), there were no significant differences in primary and secondary endpoints between the two groups although the bypass group had a higher Rutherford class than the endovascular group. Kaplan–Meier survival analysis showed that there were similar limb salvage (P = 0.95) and graft patency rates (P = 0.39). In conclusion, endovascular treatment is a valid strategy leading to an acceptable limb salvage rate for TAO patients, and surgical bypass to distal target vessels could play a vital role in cases of previous failed endovascular treatment or extensive soft tissue loss of the foot.
Although arterial bypass with autogenous vein is regarded as the ideal management strategy for patients with severe atherosclerosis obliterans (ASO) affecting the crural arteries presenting with symptoms and signs of critical limb ischemia (CLI), it is not always feasible to perform in patients with thromboangiitis obliterans (TAO). TAO frequently involves the small distal arteries of the calf and the foot causing complete obliteration of the vessel lumen, and superficial veins, used as vascular conduits for bypass surgery, may become affected by the disease in the form of phlebitis migrans with consecutive inflammatory changes [1–3]. During the past two decades, the less invasive endovascular procedure has become an alternative approach for the management of ASO due to the advances in devices and has also been attempted more frequently in TAO patients . However, unsuccessful endovascular treatment or repeated occlusions after an endovascular procedure are indications for bypass to the pedal or plantar arteries in selected patients. Furthermore, even after successful endovascular treatment, patients with extensive soft tissue loss of the foot may not heal spontaneously, requiring microvascular free flap transfers to cover large defects and gangrenous areas for limb salvage; these patients might benefit from surgical bypass of the foot arteries [4–7]. For patients with CLI with no option for endovascular or surgical treatment, distal vein bypass (venous arterialization), using the disease-free venous bed as an alternative conduit for perfusion of the peripheral tissues with arterial blood, could be a valuable treatment option for limb salvage, with a reported limb salvage rate of 75% at 12 months [8,9].
Of the 177 consecutive patients with the diagnosis of TAO, 33 patients presenting with CLI who underwent an endovascular procedure (n = 22, 67%) or bypass surgery (n = 11, 33%) were included in the analysis; we excluded 144 patients not indicated for endovascular or surgical treatment. Among the 144 patients excluded from this study, 5 patients (3.5%) underwent major amputation without any interventions (3 patients) or failed endovascular treatment at outside facility (2 patients). The baseline and clinical characteristics of the study population are presented in Table 1. The median age was 42 years (range, 20–71 years), and 97% of the patients were male. All patients were current (n = 25, 76%) or past (n = 8, 24%) smokers but were without serious cardiopulmonary comorbidities. There were no significant differences between the endovascular and bypass groups in demographics, smoking history, and arterial lesion involvement, except that patients who had bypass surgery were younger (P = 0.03) and had a higher Rutherford class (P = 0.01) than those who had an endovascular procedure. Endovascular procedures were performed as follows: plain balloon angioplasty in 12 patients, stent placement in 6 patients, and thrombolysis with plain balloon angioplasty in 4 patients. In the bypass group, the indication for bypass surgery was an ulcer or gangrene (Rutherford class 5 or 6), but 45% of the patients had rest pain alone (Rutherford class 4) in the endovascular group. Operative details for the bypass group are given in Table 2. Six patients (55%) had undergone previous failed endovascular procedures and/or arterial bypass surgery to the index limb before inframalleolar bypass, and three (27%) had previously received other procedures such as sympathectomy and minor amputation. Distal vein bypass was performed in three patients (27%) and operative adjuncts were done in eight patients (73%).