Maximizing Vein Conduit for Autogenous Bypass

Maximizing Vein Conduit for Autogenous Bypass

Gregory J. Landry


  • A history of cardiovascular risk factors should be elicited in all patients undergoing lower extremity bypass, including smoking history and history of cardiac and cerebrovascular disease and history of diabetes, chronic kidney disease, hyperlipidemia, and chronic obstructive pulmonary disease.

  • Upper and lower extremity pulse exam should be performed. Because atherosclerosis is a systemic disorder, the following pulses should be assessed bilaterally: carotid, brachial, radial, femoral, popliteal, dorsalis pedis, and posterior tibial. Both the presence and strength of pulses should be recorded.

  • If lower extremity pulses are absent, which is usually the case in patients undergoing surgery for peripheral vascular disease, ankle-brachial indices should be measured. The highest ankle pressure is divided by the highest brachial pressure.

  • Lower extremities should be evaluated for the presence of ulcerations or gangrene.

  • A history of prior vein use or removal should be elicited. Veins may have previously been used for prior lower extremity or coronary artery bypass. Patients with varicose veins may have undergone prior vein stripping or ablation. Patients with chronic kidney disease may have had prior upper extremity arteriovenous fistula placement. In dialysis-dependent patients, upper extremity veins should be used judiciously as they may be necessary for future arteriovenous access.


  • All patients considered for lower extremity bypass should undergo arteriography to define the proximal (inflow) and distal (outflow) targets.

    • Digital subtraction angiography remains the gold standard and provides the greatest anatomic detail for operative planning.

    • Alternative imaging modalities include computed tomography (CT) and magnetic resonance (MR) angiography or duplex ultrasonography.

  • Duplex ultrasonography should be used for preoperative vein mapping to identify suitable autogenous conduit (FIG 1). If the patient has good-quality GSV, no further vein mapping is typically necessary. If the GSV is of poor quality or absent, small saphenous vein and arm vein should be mapped (FIG 2).

    • Ideal conduit diameter is 3.5 mm or greater.

    • Vein should be easily compressible. Thick-walled or noncompressible vein indicates prior superficial venous thrombosis and vein is likely not suitable for bypass.

    • Mapping should ideally immediately precede surgery with vein course marked with an indelible marker on the skin. This allows precise placement of incisions, which avoids the creation of skin and tissue flaps that might impede wound healing.


  • Preoperative planning

    • If not previously marked or if marks have faded, it is useful to remark the intended venous conduit with ultrasound guidance prior to surgery (FIGS 3 and 4).

    • Open foot lesions or gangrene should be covered with sterile adhesive to prevent contamination of sterile incisions.

    • Prophylactic intravenous antibiotics should be administered to reduce risk of perioperative infection.

    • If arm vein is to be harvested, it is important to avoid blood draws or intravenous lines in the intended arm(s). If veins from both arms are necessary, central venous access may be necessary.

  • Positioning

    • The majority of the procedures are performed with the patient supine. If small saphenous vein is the intended conduit, it is often easier to perform this part of the procedure with the patient prone and then to reprepare and drape with the patient supine.

    • If arm vein is to be harvested, the arms should be abducted and placed on arm boards.

FIG 1 • Lower extremity venous anatomy.

FIG 2 • Upper extremity venous anatomy.

FIG 3 • Lower extremity vein mapping with marking of GSV.

FIG 4 • Upper extremity vein mapping with marking of the cephalic and basilic veins.