Vascular access for noncardiac procedures

Introduction

Endovascular intervention has become the primary approach to treating vascular diseases in many extracardiac territories, with open surgical procedures reserved for refractory or complex cases. These approaches are well established to address both arterial and venous diseases. Current techniques allow for approaching lesions or occlusions in the arteries that supply the leg, pelvic vessels, abdominal organs, upper extremities, and even the carotid arteries. Additionally, endovascular techniques allow for treatment of aortic aneurysms ( Table 13.1 ). Other techniques can be applied to the treatment of deep venous thrombosis, venous compression syndromes, vena cava filter implantation and removal, and treatment of pulmonary embolism, including thrombectomy or catheter-directed lysis. Some standard views for angiography are listed in Table 13.2 . The full breadth of these procedural techniques is beyond the scope of this chapter. Because interventional cardiologists that perform diagnostic and therapeutic coronary interventions are familiar with primary femoral and radial approaches, which are covered in other chapters, those techniques will not be covered here. Here, we will discuss considerations and approaches to vascular access that may be useful to the endovascular interventionalist.

Femoral access

The femoral artery remains the mainstay of access for peripheral vascular interventions. The traditional approach involves retrograde access in the common femoral artery, which allows arteriography (“runoff”) of the ipsilateral limb and subsequently offers the ability to engage the abdominal aorta and the contralateral iliac artery ( Fig. 13.1 ). Alternatively, the artery can be accessed in antegrade fashion, allowing for in-line access of the vessel to treat lesions involving the ipsilateral limb. This approach is frequently used to treat difficult lesions at the level of the distal superficial femoral artery or below, especially in the setting of aortoiliac tortuosity or stenoses. Femoral access is frequently performed using both fluoroscopy and ultrasound guidance to avoid access through calcified plaque and to ensure that a closure device can be used successfully at the termination of the procedure.

Crossing “up and over”

Crossing “up and over” for peripheral arteriography remains the standard approach for access because it allows for visualization of the arterial anatomy of both limbs and of the aortoiliac anatomy, the so-called “inflow.”

• 1.

  Access the common femoral artery (CFA) contralateral to the side of interest. Place a standard sheath for either diagnostic angiography using a modified Seldinger technique.

• 2.

  Ipsilateral runoff is frequently performed in advance of iliac crossover. Orient the image intensifier at 30 degrees ipsilateral-oblique to open the femoral bifurcation. This orientation will similarly display the infrapopliteal vessels with minimal overlap when performing distal vessel runoff angiography.

• 3.

  Inflow aortography is performed with a catheter inserted through the sheath into the distal abdominal aorta. This can be used to visualize the abdominal aorta (infrarenal or suprarenal if desired) and the aortic and iliac bifurcations. Multiple catheters can be used for this purpose, including Pigtail, Omniflush, and SOS catheters. Have the patient perform an expiratory breath hold under digital subtraction angiography. This can be performed in a straight anteroposterior (AP) projection for a standard view. The common iliac-internal/external bifurcation may also be imaged by positioning the image intensifier 20 degrees contralateral/20 degrees caudal to the bifurcation of interest. Place the image intensifier in a vertical (portrait) orientation, raise the table at maximum height to increase the signal to object distance, and lower the image intensifier to the patient to maximize the field of view. Full opacification can be achieved with dilute contrast (we use 50% contrast diluted with normal saline) and a 20cc rapid injection.

• 4.

  There are several catheters available for crossing the iliac bifurcation. For angulated bifurcations, an Imager II (Boston Scientific) or Omniflush (Angiodynamics) offers optimal engagement of the bifurcation because of its shape and presence of radio-opaque tips and simultaneously allows for injection through its side-hole catheter tips. Position the catheter low in the abdominal aorta such that an atraumatic guidewire, commonly a Glidewire or Glidewire Advantage (Terumo), can engage the contralateral iliac artery. The catheter and wire are withdrawn together (so-called “seating the bifurcation”) to allow for firm engagement of the catheter, which allows the wire to be advanced down the contralateral iliac artery.

• 5.

  After the contralateral iliac/femoral artery is wired, advance the catheter to the top of the femoral head and angle the image intensifier to 30 degrees ipsilateral-oblique to this limb. Perform runoff angiography. If the decision is made to intervene, then a guiding sheath will need to be inserted. Most contemporary equipment can be delivered through a 6 French (F) or 7F sheath. To perform a sheath exchange, advance a supportive wire through the catheter into a safe distal vessel in the leg of interest and remove the catheter and short sheath. Insert a long braided sheath “up and over” and advance to the desired vascular territory to be intervened upon. For an ostial/proximal superficial femoral artery (SFA) stenosis or occlusion, the sheath would be positioned into the CFA while using the profunda femoris artery (PFA) to position the guidewire as a “rail.” Caution should be maintained when wiring the PFA. For most SFA interventions, a 40- to 50-cm sheath is used. Longer sheaths are frequently used when intervening on more distal vessels if inflow is relatively normal.