Telescoping Microcatheter Support for Crossing Severely Calcified Chronic Total Occlusions in Below-the-Knee Arteries

Purpose: The incidence of lower limb amputation in patients with peripheral arterial disease (PAD) and chronic limb ischemia (CLI) has been shown to increase in recent years as a result of increasingly complex stenotic lesions and chronic total occlusions (CTOs). Lower limb amputations often occur as a result of an inability to gain guidewire access to support subsequent treatment modalities during interventional procedures. High-grade stenosis in addition to the presence of moderate to severe calcification often requires new approaches as well as catheter systems that provide improved support or enable wire escalation techniques. One technique that offers significant advantages but is commonly limited by device profile is telescoping dual support or using a microcatheter inside a 4- or 5-Fr catheter to provide wire support when crossing. The 2F XO Cross Microcath incorporates a nontapered shaft design which enables telescoping support through any standard 4- or 5-Fr catheter.

Materials and Methods: A patient with PAD with a severely calcified CTO in the posterior tibial artery was identified as a candidate to use the nontapered 2-Fr XO Cross Microcath in a coaxial dual support catheter configuration. This case was documented as the first use of the XO Cross in a coaxial dual support treatment strategy and has since been used in multiple subsequent cases.

Results: The posterior tibial artery CTO was 100 mm in length with severe calcification present. The pretreatment angiogram showed no flow and a nonexistent proximal cap at the origin of the artery. The coaxial dual support catheter support system used an Abbott Command 14 guidewire, a 2-Fr XO Cross 14-135, and 5-Fr Merit Berenstein 100 angled. The Berenstein and XO Cross were positioned at the origin of the artery to provide support for lesion entry and crossing. With the XO Cross protruding out from the Berenstein tip, the Command guidewire was pushed beyond the XO Cross tip and successfully navigated across the lesion. The XO Cross was then advanced over the guidewire using a unique torque-to-advance technique. This approach enabled a quick and efficient crossing method that allowed for subsequent wire exchanges to deliver angioplasty and orbital atherectomy for successful recanalization.

Conclusions: With the advent of new lower profile catheter systems, coaxial dual support can provide an advantageous and efficient approach for crossing difficult below-the-knee lesions.