Infrainguinal Endovascular Reconstruction: Technique and Results

Approaches

Percutaneous intervention for infrainguinal occlusive disease is usually performed through the contralateral femoral artery using an up-and-over approach or through the ipsilateral femoral artery using an antegrade approach ( Table 30.1 ). Infrainguinal interventions can also be performed through the brachial artery, but this approach is rarely required and may be more challenging because of the longer distances involved and the higher likelihood of access-related complications. More recently, pedal approaches have been used for distal tibial interventions or when antegrade access is not possible. The primary advantages of the up-and-over approach, which is most commonly used, are the following: An aortogram with runoff can be easily converted to endovascular therapy; it permits evaluation of the inflow aortoiliac arteries before treatment of infrainguinal lesions; only a simple retrograde femoral puncture is required; and it facilitates selective catheterization of the superficial femoral artery (SFA) orifice and treatment of proximal SFA lesions, which can be difficult via the ipsilateral antegrade approach. Furthermore, puncture site management is contralateral to the intervention site rather than proximal to it. The antegrade approach may be used for better guidewire and catheter control in infrapopliteal intervention and in patients who have contraindications to the up-and-over approach. The likely approach is determined before the procedure to facilitate room setup and the availability of supplies, but both groins are always prepared in case an alternative approach is required during the procedure.

Platforms

Percutaneous intervention in the infrainguinal circulation can be achieved with 0.035-inch, 0.018-inch, or 0.014-inch platforms, using sheath sizes ranging from 4 to 7 French. Most diagnostic angiograms and interventions are begun with a standard 0.035-inch platform. This platform has several advantages: the guidewires and catheters are easy to handle, the inventory is usually readily available, the fluoroscopic visualization of these larger-caliber devices is simpler, and the larger guidewires and catheters are often more helpful than the smaller diameter devices when crossing chronic or heavily calcified occlusions. However, there are also some significant disadvantages of 0.035-inch systems: the larger-caliber guidewires and catheters may not easily cross critically diseased segments and may be more prone to cause arterial damage; at longer distances, these catheters lose their “pushability” because of high friction; and in small arteries such as tibial vessels, the standard platform devices may be too big. In addition to their smaller crossing profiles, the smaller 0.018- and 0.014-inch platforms tend to be more trackable in small, tortuous vessels at locations distant from the access site, especially when using monorail (rapid-exchange) systems with longer guiding sheaths or catheters. Most of the coronary devices are on a 0.014-inch or 0.018-inch platform, as are current atherectomy systems; therefore the array of available balloon catheters and stents is much broader with this system. Monorail balloon catheters permit better pushability because the friction of the guidewire on the balloon catheter lumen occurs over a much shorter distance than with coaxial balloon catheters. Monorail systems have the additional advantages of greater ease of use (especially with a single operator), shorter required guidewire lengths, and less guidewire movement during catheter exchanges.

Sheaths

For initial diagnostic angiography, a 5 French sheath is generally used in conjunction with 5 French diagnostic catheters (Omni Flush [AngioDynamics, Queensbury, NY] or VCF [Cook Medical, Bloomington, IN] catheter for aortography with runoff; Kumpe or Angled Glide [Cook Medical] catheter for selective angiograms). Although angioplasty alone can be performed through 4 or 5 French sheaths, especially when using balloons designed for 0.014- or 0.018-inch platforms, most stents and atherectomy devices require larger sheaths. As a result, most interventionists will change to a larger sheath for intervention once diagnostic angiograms have been performed and the operator has decided to proceed with intervention. It is important to note that with the advent of better percutaneous closure devices, sheath size has become a less important consideration because the larger puncture holes can be closed safely and easily in a percutaneous fashion in most patients, without the need for manual compression.

Technique