Thoracofemoral (Thoracic Aortofemoral) Bypass

The typical treatment for aortoiliac occlusive disease is an aortofemoral bypass graft, with patency rates of approximately 83-92% at 5 years. ^[1] Less invasive approaches have been studied. ^{[2, 3]} Thoracofemoral (thoracic aortofemoral) bypass is an alternative surgical bypass that is indicated for aortoiliac occlusive disease when traditional aortobifemoral bypass is contraindicated. ^[4] These conditions occur when performing a transabdominal or retroperitoneal abdominal procedure is difficult or impossible, as may be the case, for example, in the following circumstances:

• Prior abdominal irradiation
• Multiple abdominal interventions
• Colostomy
• Proximal aortic disease in close proximity or above the renal arteries
• Failure or infection of previous abdominal aortic surgery

Some surgeons have advocated thoracofemoral bypass as a primary treatment for isolated aortoiliac occlusive disease, at least when the disease is in close proximity to the visceral or renal arteries. ^[1] Reported patency rates for thoracofemoral bypass have rivaled those of the traditional aortofemoral bypass, at approximately 81% at 5 years. ^[1]

Indications for thoracofemoral bypass include the following:

• Aortic graft failure ^[5]
• Graft infection
• Hostile abdomen ^[6]
• Occlusive disease in close proximity to the visceral or renal arteries
• Other intra-abdominal pathologies not amenable to standard aortofemoral revascularization

Although some advocate the use of thoracofemoral bypass as a primary procedure, most surgeons consider it a secondary procedure with the previous indications. ^[1]

Contraindications for a thoracofemoral bypass graft include the following:

• Severe pulmonary insufficiency in a patient who is hence unable to tolerate a thoracotomy
• Unapproachable thoracic aorta

A limiting factor is a prior thoracic operation that precludes or complicates the approach to the descending aorta.

Crawford et al studied outcomes in 41 patients (age, 61 ± 9 years; 54% female; 7% in a hypercoaguable state) who underwent thoracofemoral bypass for occlusive disease. ^[7]  Mean preoperative ankle-brachial index (ABI) was 0.4 bilaterally. Indications included critical limb ischemia (CLI; 56%), claudication (30%), acute limb ischemia (7%), and combined aortoiliac occlusive disease and mesenteric ischemia (7%). Seven patients (17%) had previously undergone aortofemoral bypass, and 15 (38%) had previously undergone any prior aortic operation. Adjunctive visceral bypass occurred in eight patients (20%).

The postoperative duration of stay in this study was 11 days, and 30-day mortality was 5%. ^[7] Major complications occurred in 34% of patients. Mean postoperative ABI was 0.9 bilaterally. At a median follow-up of 7 months, five patients underwent some form of reintervention. Estimated 3-year primary limb patency and freedom from major adverse limb events were 80 ± 10% and 70 ± 10%, respectively. Estimated 5-year survival was 93 ± 5%.

Stewart et al, using data from the Vascular Quality Initiative (VQI) suprainguinal bypass module, evaluated outcomes of 154 thoracofemoral bypass procedures performed to treat occlusive disease between 2009 and 2019. ^[8]  Fifty-nine patients (38.3%) had a prior inflow bypass, and 22 (14.2%) had a prior leg bypass. Indications for the procedure included claudication (42.9%), rest pain (38.3%), tissue loss (12.3%), and acute limb ischemia (6.5%).

Major complications occurred in 31.2% of the cohort, and acute limb ischemia and claudication were associated with increased rates of such complications (acute limb ischemia, 60.0%; claudication, 34.8%; CLI, 24.4%). ^[8] Survival at 30 days was 95.5%; estimated 1-year survival was 92.7% ± 2.2%. Primary patency was 92.9% at discharge and 89.0% at 1 year. Postoperative major amputation occurred in one patient during the index hospitalization; estimated freedom from major amputation at 1-year follow-up was 97.1% ± 2.2%. Two patients developed in-hospital bypass occlusion, and three patients had occlusion occurring within 1 year; overall freedom from occlusion was 96.8% at 1 year.