Case report: lateral axillary-profunda femoris artery bypass for acute lower limb ischemia due to thrombosis after bilateral axillofemoral bypass

Axillofemoral bypass (axillary-femoral bypass) is usually used as one of the surgical methods for the treatment of Leriche syndrome and abdominal aortic aneurysms. It is an important extra-anatomical surgical approach and includes a variety of surgical procedures, such as axillary-unilateral femoral artery bypass, axillary-bilateral femoral bypass and bilateral axillary-femoral artery bypass [1]. Its patency rate is generally not superior to that of intra-anatomical abdominal aorto-bifemoral bypass, but it can play important roles in conditions such as a hostile abdomen and infectious abdominal aortic aneurysms [2‐4]. Long-term complications after axillofemoral bypass include thrombosis, lower extremity arterial embolism and infection. Based on the urgency of symptoms and the cause and extent of thrombosis, limb ischemia caused by thrombosis after axillofemoral bypass can be treated by a variety of surgical methods, including thrombectomy of an artificial blood vessel, femoral artery patch angioplasty, and femoropopliteal bypass [1]. Lateral axillary-profunda femoris artery (LAx-PF) bypass, a non-routine bypass, has not been reported for the treatment of this type of complication.

Axillofemoral bypass is usually used as one of the surgical methods for the treatment of Leriche syndrome and abdominal aortic aneurysms. It is an important extra-anatomical surgical approach and includes a variety of surgical procedures such as axillary-unilateral femoral artery bypass, axillary-bilateral femoral bypass and bilateral axillary-femoral artery bypass [1]. Axillofemoral bypass was originally proposed by Blaisdell and Hall in 1963 [6]. If a patient has bilateral lesions, femorofemoral (femoral-femoral) bypass can be performed concurrently, that is, axillary-bifemoral artery bypass [7]. Its patency rate is generally not more ideal than that of intra-anatomical abdominal aorto-bifemoral bypass, but it can play important roles in conditions such as a hostile abdomen and infectious abdominal aortic aneurysms [2‐4]. The patient underwent the prior procedure due to ischemic symptoms caused by Leriche syndrome. We discussed with the patient the benefits and risks of different surgical procedures including open surgery and interventional surgery. Because the patient’s abdominal aortic occlusion was at the level close to the renal artery, in order to avoid major trauma of open surgery, the high cost of interventional surgery and the risk of potential renal damage, we ultimately decided to perform bilateral axillofemoral bypass for surgical treatment. The procedure went smoothly. The patient recovered well after surgery with satisfactory patency of the bypass vessels.

The axillary artery is divided into the medial, middle and lateral segments by the pectoralis minor. In early studies, axillary-bifemoral artery bypass was created by using the proximal segment, that is, the axillary artery on the proximal edge of the pectoralis minor muscle, as the inflow vessel. In a subsequent study [1] and in our study, we used the middle segment, that is, the axillary artery behind the pectoralis minor muscle, as the inflow vessel. The advantages of using the middle segment of the axillary artery as the inflow vessel includes relatively easy exposure and a lower risk of brachial plexus injury. However, the use of the lateral axillary artery, that is, the axillary artery at the edge of the pectoralis major muscle and at the axillary fossa, as the inflow vessel for axillofemoral bypass has not been reported. In this case, we confirmed by angiography that there was no obvious stenosis from the left subclavicular artery orifices to the axillary artery, and the anastomosis between the original medial segment of axillary artery and the graft did not affect the diameter of the vessel. Therefore, it was reliable to use the lateral axillary artery as the inflow passage. In terms of the selection of the outflow vessel, the common femoral artery is always the best choice. Because an artificial blood vessel can play a similar role as a patch to widen the femoral artery, the blood flow in the bypass can directly supply the deep femoral artery and the superficial femoral artery simultaneously [1]. In cases where the superficial femoral artery is unobstructed or may be reestablished by endovasuclar treatment, the superficial femoral artery is still a better outflow vessel than the deep femoral artery. If the superficial femoral artery is occluded but the deep femoral artery is patent, lower extremity ischemia symptoms may be completely relieved. In this case, the patient had bilateral superficial femoral artery occlusion before the bilateral axillofemoral bypass was performed. However, the patient had no symptoms of lower limb ischemia and the pulses of the dorsalis pedis artery and posterior tibial artery of the bilateral lower limbs were palpable after surgery. This indicates that the blood flow of the deep formal artery is important and sufficient for lower extremity blood supply. Thus, during this procedure, we used the deep femoral artery as the outflow vessel without concerns. If the patient is considered to have insufficient blood flow when using the deep femoral artery as the outflow vessel, an additional femoral popliteal bypass or axillopopliteal bypass may be performed. Table 1 shows the indications and limitations of the lateral axillary-profunda femoris artery bypass.

Axillofemoral bypass can be performed under a variety of anesthesia, including general anesthesia, local anesthesia, regional anesthesia and even epidural anesthesia [8]. One of the reasons axillofemoral bypass was used to replace abdominal aorta-femoral artery bypass is that the risk of anesthesia is less in the former than that in the latter (open surgery). We chose general anesthesia for this procedure in this patient, and no obvious anesthesia complications and perioperative cardio-cerebral vascular accidents occurred. Based on the anesthesia experience from the arteriovenous fistula of the upper arm, LAx-PF bypass can be performed under local anesthesia to minimize the risk of general anesthesia for patients.

Complications after axillofemoral bypass include thrombosis, lower extremity arterial embolism and infection. Like other bypasses, the main complication of axillofemoral bypass is still postoperative thrombosis, which is often secondary to intimal hyperplasia of the distal anastomosis. For patients with bilateral lesions, such as Leriche syndrome, axillary-bilateral femoral bypass or axillofemoral bypass is an option. The patency rates of axillary-bifemoral artery bypass and axillary-unilateral femoral artery bypass are reported inconsistently. Early studies have shown that the patency after axillary-bifemoral artery bypass is higher, probably because the blood flow is bifurcated by two outflow vessels and reduces the impact on the distal artery of the anastomosis and thus reduces the degree of intimal hyperplasia [9]. Moreover, it is often secondary to intimal hyperplasia at the distal end of the anastomotic site [9]. Other causes of graft thrombosis may include anastomotic stenosis, inflow stenosis, and hypercoagulability. However, recent large-sample-sized studies have shown that the 1-year patency rates for axillary-bifemoral artery bypass and axillary-unilateral femoral artery bypass are similar [10]. Courbier et al. showed that the 5-year patency rate for axillary-bilateral formal artery bypass is between 30 and 85% [11]. A study by Blaisdell et al. showed that the 2-year patency rate for bilateral axillofemoral bypass was 75%, while that for unilateral axillofemoral bypass was 50% [12]. The long-term patency rates for bilateral axillofemoral bypass and axillary-bilateral femoral bypass remain unclear. Moreover, a study that included a small number of cases suggested that in some nonobstructive lesions, for instance, axillary-bilateral femoral bypass for the treatment of abdominal aortic aneurysms may not provide sufficient blood flow to the bilateral lower limbs, and thus bilateral axillofemoral bypass is needed [13]. In addition, there are different specific anastomosis methods for axillary-bifemoral artery bypass. Some surgeons anastomose the femoral-femoral bypass vessel to the autologous common femoral artery [6]. Others anastomose the femoral-femoral bypass vessel to the artificial vessel for axillofemoral bypass [14]. Obviously, if thrombus occurs in a patient undergoing axillary-bifemoral artery bypass, the thrombus may grow into the autologous and artificial blood vessels and result in simultaneous ischemia of the bilateral lower limbs [15]. If a patient undergoes bilateral axillary-femoral bypass, unilateral thrombosis will not affect the contralateral lower limb. Surgical treatment for acute ischemia of one limb is easier than that for bilateral limbs. Therefore, we use bilateral axillofemoral bypass instead of axillary-bifemoral artery bypass. This patient had a unilateral axillary-femoral artery bypass thrombosis, and angiography showed that the contralateral bypass was completely unobstructed with no significant anastomotic stenosis. Although we can solve left lower limb ischemia by performing right femoral-left femoral deep artery bypass, we still choose to use the left lateral axillary artery as the inflow vessel.

There are many surgical treatments for limb ischemia caused by delayed thrombosis after axillofemoral bypass. Different surgical methods can be chosen according to the symptoms, timing, location and scope of the thrombosis, including drug thrombolysis, thrombectomy of the artificial blood vessel or autologous vessel, patch angioplasty, distal bridging bypass and aortic-bifemoral bypass [1, 16‐18]. Because most chronic thromboses are secondary to the narrowing of the outflow vessel anastomosis, maintaining patency of the outflow vessel is the focus for a successful procedure [1]. In this patient, the previous anastomosis was located at the femoral artery bifurcation, the original superficial femoral artery had been completely occluded for a long time, and the deep femoral artery was well compensated; therefore, we chose the deep femoral artery as the outflow vessel. However, we did not expect that the inflow vessel could not be used for thrombectomy to restore blood flow. One reason may be the severe stenosis of the inflow vessel due to anastomotic hyperplasia, and the other reason is that the anastomosis angle between the artificial vessel and axillary artery was closer to 90 degrees, which made the embolization catheter difficult to pass. Therefore, some researchers have proposed that the anastomotic angle between the axillary artery and the femoral artery should be more acute to thereby make the anastomosis relatively wider and to reduce the anastomosis stenosis and anastomotic tension caused by shoulder movement [1].

Due to advances in endovascular interventional surgical instruments and methods in the past 10 years, axillofemoral bypass as a surgical method to treat Leriche syndrome has gradually become useless. It is more often used as a backup surgery for infectious abdominal aortic aneurysms [19]. However, we still need to deal with the postoperative complications of this type of bypass surgery, such as thrombosis and infection. The LAx-PF bypass provides a simple and convenient surgical solution for the treatment of acute lower limb ischemia caused by axillary-femoral artery thrombosis.

We treated a patient with acute ischemia of the lower extremity due to thrombosis after bilateral axillofemoral bypass. Late-stage thrombosis after axillofemoral bypass can cause acute lower limb ischemia. If thrombectomy cannot restore blood flow in the previous bypass vessel, LAx-PF bypass is an easy procedure to rescue the ischemic limb.