Preprocedural Evaluation
Preoperative workup should begin with noninvasive arterial physiologic studies, including ankle-brachial index (ABI) and arterial wave form analysis by duplex ultrasonography (US). If iliac occlusive disease is suspected, at least one imaging study should be performed for assessment of the arterial anatomy. Computed tomography (CT) angiography (CTA), magnetic resonance angiography (MRA), or arteriography provides anatomic information for the needed revascularization procedure.
If femorofemoral (femoral-femoral) bypass is indicated, a thorough imaging assessment of the inflow iliac system is critical in that it facilitates planning for possible adjunctive procedures (ie, endovascular interventions or limited endarterectomy) to ensure the success of the reconstruction and augment overall long-term graft patency. [9]
Equipment
Equipment employed for a femorofemoral bypass is as follows:
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Standard vascular clamps and instruments
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Tunneling device (ie, Gore tunneler; W. L. Gore and Associates, Flagstaff, AZ)
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Polytetrafluoroethylene (PTFE) or Dacron-based aortic grafts (8-10 mm) of appropriate length and configuration
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Continuous wave Doppler device to assess blood flow intraoperatively
Most femorofemoral bypasses are constructed with prosthetic grafts. Dacron or PTFE-based grafts are most commonly used for the procedure. Autogenous (vein) and biologic grafts (cadaveric vein or artery) may also be used if prosthetic reconstruction is contraindicated because of the presence of an active infection or contamination of the surgical field. Most studies have not shown differences in patency rates among the various types of graft used. A study by Nguyen et al found femoral vein grafts to have superior patency as compared with PTFE grafts. [10] Externally supported grafts may facilitate graft tunneling and lie. [11]
Patient Preparation
Anesthesia
Femorofemoral bypass is most often performed with general anesthesia because tunneling of the graft can be difficult to tolerate. In cases where underlying cardiopulmonary disease precludes general anesthesia, however, the procedure can be performed with regional (spinal) or local anesthesia and sedation.
Positioning
The procedure is performed with the patient positioned supine, and a wide sterile field is prepared from the abdomen to the lower anterior thighs.
Monitoring & Follow-up
The utility of routine graft surveillance with duplex US has not been definitevely established, but some studies showed that peak systolic velocities higher than 300 cm/s at the inflow anastomosis, or midgraft velocities lower than 60 cm/s, were predictive of impending graft thrombosis. [12] Routine measurement of the ABI is recommended at follow-up. If the ABI falls by more than 0.15, further investigation is warranted.
The 2018 guidelines from the Society for Vascular Surgery (SVS) recommended clinical examination and ABI measurement, with or without the addition of duplex US, in the early postoperative period to provide a baseline for further follow-up after femorofemoral bypass; this evaluation would be repeated at 6 and 12 months and then annually as long as there are no new signs or symptoms. [13]
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Tunneling of the femoral-femoral bypass.
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Femoral-femoral bypass configuration.
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End-to-side graft to femoral anastomosis.
