Desperate Times Require Complex Measures: An AV Reversal Case Study

Case Study

This is a 44-year-old male with a past medical history of coronary artery disease, myocardial infarction (MI) x4, percutaneous coronary intervention with stenting, hypercholesteremia, peripheral artery disease, and smoking. He had been diagnosed as a clopidogrel non-responder; however, we initiated an identified dual antiplatelet therapy that he tolerated and the patient has since been without recurrent MI.

The patient presented with Rutherford Class 6 with left foot erythema present in the 1st, 2nd, and 3rd toes. The left great toe tip was blackened with skin breakdown underneath the toenail, and with necrosis in the intra-digital space between the 1st and 2nd toes.  The patient also experienced severe rest pain. There were known bilateral popliteal aneurysms with thrombosis, diagnosed over the previous 10 months. 

Diagnostic angiogram revealed right-sided flow into the tibioperoneal trunk (TPT) with no signs of distal reconstitution of the major tibial and pedal vessels, consistent with a desert foot (Figure 1A-B). This type of patient is usually not a surgical candidate, as there would be no targets. Sometimes one can attempt endovascular therapy, and it was attempted in this case, with 48 hours of lytic therapy, but it was without success in terms of resolution of what is considered chronic thrombo-embolization. The question that comes to mind at this point is, why did it take so long for this patient to reach a center that has the ability to provide alternative therapies? The time of onset of symptoms to the time the patient presented for the current procedure was over 10 months. Ten months, to a CLI patient, is a lifetime.  

With no other endovascular or surgical options other than amputation, an arteriovenous (AV) reversal procedure was planned. The steps for this procedure are as follows:

Step 1: Antegrade access with 7 French sheath placement, advancing a wire to the proximal posterior tibial artery (the location where the crossover from the arterial to the venous conduits is to take place). Once there, progressive balloon angioplasty is performed. (Figure 1)

Step 2: Ultrasound-guided access of the posterior tibial vein and placement of a 5 French sheath, followed by a venogram. An .018-inch V-18 wire (Boston Scientific) is advanced and then a 4 mm x 60 mm .018-inch Ultraverse (Bard Peripheral Vascular) is advanced over the wire. The balloon is aligned with the level of the antegrade wire. (Figure 2)

Step 3: An antegrade Outback device (Cordis) is advanced and aligned with the proximal edge of the retrograde venous balloon using fluoroscopic oblique views to align the L and the T with the balloon. After alignment, the Outback needle is fired into the balloon, which usually shows a local balloon rupture. Experience has shown the need to use only mild atmospheric pressure, inflating the balloon to 2-4 atmospheres (atms) to lower the risk of complications. Once the balloon is entered, a Mailman wire (Boston Scientific) is quickly advanced. This wire was chosen because it has a soft tip that can loop inside the balloon and a very stiff body that allows transit of equipment over it. (Figure 3)

Step 4: Now that the antegrade wire is in the retrograde balloon, the retrograde balloon is pulled while advancing the retro wire, while the antegrade wire is flossed from the venous sheath. (Figure 4A-B)

Step 5: Time to start creating the proper connection sizing between the artery and the vein. This can be done in a sequential fashion, by using a 3.5 mm x 40 mm balloon followed by angiography to ensure no extravasation exists. A 4.0 mm x 40 mm balloon can then be used, followed by an angiogram to again ensure no extravasation. (Figure 5)

Step 6: Next to be advanced is a Viabahn stent (Gore Medical). Stent size depends on the length of the reversed venous segment, but usually a 5.0 mm or 6.0 mm Viabahn by the required length to cover the entire reversed venous segment is needed. Now that the Viabahn stents are delivered and the flossing of the Mailman is no longer needed, the venous sheath is removed. The Mailman is advanced into the distal pedal veins and exchanged over a catheter to the V-18. At this point, consider placing a short 5.0 mm Viabahn over the access site, which stops any unnecessary extravasation of blood. Then, proceed to eliminate venous valves. This is a cumbersome process at times and relatively easy at others. Utilize plain old balloon angioplasty, increasing atms as needed until no waist is left on the balloon. (Figure 6A-C)

Step 7: Take an .014-inch catheter into the pedal venous system and perform a venogram to look for the anterior tibial vein connection. Use that information to advance a wire into the anterior tibial vein. (Figure 7)

Step 8: Back to the arterial venous proximal access, ending with this segment and a 4.0 mm x 38 mm drug-eluting stent. The venous portion of the stent was post dilated with a 5.0 mm balloon and the arterial portion of the stent with a 4.0 mm balloon. (Figure 8A-C)

Step 9: Final angiogram is performed, looking for brisk flow transition from the artery to the vein with an antegrade, newly reversed vein that briskly fills the entire pedal venous circulation and no evidence of early venous steal phenomenon. If that is not present, then the procedure is done. If a large venous steal phenomenon is present, proceed with coiling as necessary. (Figure 9A-B)

With expected reperfusion edema and pain, an interdisciplinary approach to aftercare is of utmost importance. Post procedure pain management is important to address. Additionally, wound care collaboration is crucial, as it is anticipated the wound will not demonstrate signs of improvement for 4-6 weeks while the body adjusts to the change in blood flow. 

Portions of this case were published in the AMPutation Prevention Symposium Show Daily, dated August 10, 2017, page 16.

Disclosure: Dr. Mustapha reports he is a consultant to Bard Peripheral Vascular and BSCI (Boston Scientific).

Dr. J.A. Mustapha can be contacted at jihad.mustapha@metrogr.org.