Despite the substantial evolution of percutaneous therapies and hybrid surgical techniques in treating atherosclerotic occlusive disease, aortobifemoral bypass remains a mainstay of therapy in the treatment of symptomatic aortoiliac occlusive disease. In appropriate surgical candidates with appropriate anatomy, aortobifemoral bypass provides a standard of durability against which alternative revascularization procedures should be measured. Historical reports documenting associated perioperative mortality rates of 5% to 8% have been supplanted over time with 30-day mortality rates of 1% to 2%, rivaling abdominal aortic aneurysm repair (AAA). Improved outcomes over time result from a myriad of etiologies including improved perioperative pharmacologic management/care, cardiac care, and antecedent coronary revascularization as well as the evolution of optimal medical therapy predicated on widespread antiplatelet and statin use.

Indications for aortobifemoral bypass include lifestyle-disabling claudication, ischemic rest pain, ischemic ulceration, or pre-ulcerated skin changes in the setting of aortoiliac occlusive disease. Often male patients will exhibit the combined additional symptoms of proximal hip girdle/buttock claudication, and erectile dysfunction consistent with Leriche syndrome seen in the setting of diminished femoral pulses. In addition, aortoiliac occlusive disease may cause microembolization to the distal forefoot leading to pre-tissue loss or even frank ulceration.

Most commonly, the terminal aorta and the common iliac arterial segments are impacted by the formation of occlusive lesions. This disease pattern can then propagate both proximally and distally. In rarer instances, thrombus may extend to the level of the renal arteries, though more commonly will spare the renal arteries and visceral aortic segment. Roughly one-third of patients undergoing aortobifemoral bypass will also exhibit significant common femoral and profunda origin disease which have potential implications regarding patient presentation as well as surgical reconstruction. Moreover, as many as 40% of patients undergoing aortobifemoral bypass will demonstrate,
SFA occlusions, highlighting the importance of satisfactory profunda outflow at the time of operation.

Contraindications for aortobifemoral bypass have historically included the presence of high-risk medical comorbidities and/or the presence of hostile anatomic factors, which can preclude the safety profile of performing a large magnitude operation with requisite aortic cross-clamping. In these circumstances, when endovascular options are not viable, extra-anatomic bypass strategies often provide an alternative for successful revascularization. While considered less durable, the physiologic footprint of these alternative procedures, most commonly axillobifemoral bypass, is better tolerated among debilitated patients in need of arterial inflow.

Given the operative magnitude of aortobifemoral bypass grafting, preoperative evaluation of a patient’s candidacy for surgery is warranted. As many as 40% of patients with aortoiliac occlusive disease have significant coronary artery disease. Thus, candidates for surgery should likely be interrogated for clinically significant cardiac disease. Unstable angina or other symptoms referable to cardiac occlusive disease justifies the need for more invasive testing including coronary angiography. Should coronary revascularization be required, this should be performed prior to aortobifemoral bypass. Likewise, pulmonary compromise warrants preoperative investigation. Patients with significant disease burden may require bronchodilator therapy, smoking cessation, and pulmonary toilet prior to revascularization. Patients with significant coronary and/or pulmonary compromise who are not appropriate candidates for cardiac or pulmonary therapy may require extra-anatomic bypass.

Preoperative imaging is of paramount importance in operative planning prior to surgery. Noninvasive vascular lab testing with ankle brachial indices is often useful as a first diagnostic study to objectively quantify the degree of circulatory compromise. Additional imaging protocols have shifted over time for patients with aortoiliac occlusive disease. Historically, two-dimensional digital subtraction angiography (DSA) was utilized among those with symptomatic aortoiliac disease. This modality remains a mainstay among those who are candidates for percutaneous therapies. Contrast CT arteriography has supplanted DSA, as CT imaging has become more sophisticated. Our practice routinely relies upon contrast CT angiography for patients with suspected aortoiliac disease in the setting of attenuated femoral pulses. This modality also permits three-dimensional interrogation and reconstruction allowing for optimal arterial visualization, disease burden, and distribution which are essential for operative planning. Magnetic resonance angiography (MRA) also permits high quality imaging of the aortoiliac and lower extremity arterial segments though our practice favors CT imaging. Of note, as more patients undergoing aortobifemoral bypass present having undergone prior failed iliac stenting procedures, MR can often be confounded by signal dropout referable to previously placed stents, thus compromising the accuracy of this modality.

Considerable attention has been devoted to the surgical technique of aortobifemoral bypass with particular focus on the method of reconstruction. End-to-end repair versus end-to-side techniques have inspired considerable debate and conjecture regarding the merits and pitfalls of each. Traditionally, enthusiasts for end-to-end repair have cited facilitated proximal
aortic thrombectomy and decreased perceived incidence of aortoenteric fistula formation as potential advantages. Furthermore, this technique offers definitive repair for those patients who present with concomitant aneurysmal degeneration in the setting of their symptomatic occlusive disease. In addition, end-to-end reconstruction theoretically minimizes any distal embolic complications in light of oversewing the distal aortic stump. By comparison, end-to-side reconstruction is perceived to assure the preservation of antegrade aortoiliac perfusion in the setting of a patent IMA, or hypogastric artery. Often this anatomic scenario reflects patent proximal iliac circulation in the setting of external iliac occlusions (Fig. 19.1).