Going Below the Knee: Not Without Challenges

By all accounts, leg ischemia caused by below-the-knee (BTK) arterial occlusive arterial lesions is an important and frequent form of atherosclerotic vascular disease. Until the recent past, BTK revascularization was long considered a “sacred domain” of surgical (bypass) treatment — with little if any room left for catheter-based therapy. We know better today.¹ The BTK territory, in fact, can be appropriately thought of today as one of the most promising frontiers in the entire endovascular field when the potential for growth and patient benefit are taken into account. Balloon angioplasty (PTA) has been and remains the most useful tool in the hands of interventionists dealing with infra-genicular arteries. Its capabilities and usefulness have expanded most recently with the availability of “dedicated,” long small-vessel balloons that were developed — specifically — for use in such a vascular bed. Unlike other arterial territories (i.e., iliac and SFA) where stenting has became almost routine, the use of stent devices below the knee has not been embraced with enthusiasm by the majority of endovascular specialists who continue to regard PTA bail-out as essentially the only valid indication for scaffolding a BTK artery with a metal device — coronary balloon-expandable stents in most cases. This uneasiness reflects a number of real and perceived shortcomings surrounding the placement of stents into such vessels, but above all, it relates mainly to the collective failure of industry and thought leaders to bring appropriate focus to this “forgotten” vascular bed — interventionally speaking. But I am happy to recognize here that such state of affairs is changing rapidly, as all stakeholders have come to recognize BTK intervention as one of the brightest lights in endovascular, and availability of suitable stents for such vessels as a prerequisite for success. And that brings us to DES technologies, an unavoidable thought in a discussion of BTK stenting. It was this past June when I heard a debate during a European meeting when Bosiers et al presented his perspective on “why DES may not work below the knee.” I thought it was a unique and lucid (and thankfully brief) dissertation on a most interesting subject, and likely of much interest to the VDM readership, so I asked him to put pen to paper and write it up. He (and his team) did not disappoint. I will let the readers decide, but it sure sounds to me like a reasonable and believable argument.