Optimizing Success in Treating Occlusive Disease of the Superficial Femoral Artery

The growing epidemics of diabetes, obesity, and kidney disease have contributed to a rise in the number of patients with peripheral artery disease (PAD). Over 8 million Americans are affected by PAD.¹ Presentation of PAD can range from asymptomatic stenosis to life-limiting claudication, and at its worst, critical limb ischemia (CLI). The goal of peripheral vascular intervention is to revascularize occluded vessels to improve blood flow to the distal vasculature. 

Occlusive disease in the superficial femoral artery remains challenging to treat from an endovascular perspective because of the high rates of restenosis.² The superficial femoral artery (SFA) is unlike any other vessel in the body and presents unique challenges for endovascular intervention. Complete occlusions tend to predominate stenosis, and disease is often diffuse along the SFA. In addition, the SFA is subjected to tri-planar intermittent mechanical stresses (compression, extension/contraction, flexion, and torsion) that lead to poor performance of implanted stents.³ An interventionist must be aware of the challenges of treating SFA lesions, and be prepared to use advanced techniques and a variety of interventional devices to optimally treat these lesions. Herein, we present two cases where utilization of advanced techniques and devices allowed us to treat an SFA lesion successfully. 

Case 1

A 60-year-old female with a past medical history of hypertension, hyperlipidemia, insulin-dependent diabetes mellitus, and PAD presented to the cath lab with life-limiting claudication in her left lower extremity. The patient noted pain in her thigh radiating into her calf. She had previously undergone a peripheral vascular intervention of her left lower extremity. At her follow-up, duplex ultrasound revealed a severe stenosis of her left SFA. Diagnostic angiography of the left lower extremity confirmed 80% stenosis of the proximal SFA, patency of stents placed in the mid-distal SFA, and 90% stenosis of the tibioperoneal (TP) trunk (Figure 1A-B). The patient was anticoagulated with heparin, achieving an activated clotting time (ACT) >250. The lesion was crossed with a Runthrough wire (Terumo), which was then switched for a Viper wire (Cardiovascular Systems, Inc., [CSI]) to allow for visualization of the vessel with intravascular ultrasound (IVUS). IVUS revealed a reference size for the SFA of 6.0mm with heterogeneous plaque and the TP trunk of 3.1mm with calcific plaque (Figure 2). Noting the presence of heterogeneous and calcific plaque, we performed orbital atherectomy with a 2.0 classic Diamondback crown (CSI) to modify the plaque in both the SFA and TP trunk. We followed atherectomy with percutaneous transluminal angioplasty (PTA). In the TP trunk, a 3.0mm x 20mm balloon was followed by a 4mm x 40mm Lutonix drug-coated balloon (DCB) (Bard PV), bringing the 90% stenosis to <10%. In the SFA, a 5mm x 20mm balloon and then a 6mm x 60mm Lutonix DCB was used to reduce the 80% stenosis to <10% (Figure 1C-D).

Case 2

A 65-year-old female with a past medical history of hypertension, hyperlipidemia, coronary artery disease, and PAD presented to the clinic with life-limiting claudication of her right lower extremity. She had undergone peripheral vascular intervention of her left lower extremity three years prior. At the time of the intervention, a significant stenosis of the right SFA was noted. She presented to the cath lab for evaluation and subsequent intervention of her right lower extremity. Diagnostic angiography of her right lower extremity revealed a 100% mid/distal stenosis of the SFA (Figure 3A). The patient was anticoagulated with heparin, achieving an ACT >200. An 18g Cook chronic total occlusion (CTO) wire was used to cross the proximal cap of the stenosis. The SPINR (Merit Medical), a novel tool that mechanically revolves a wire mechanically, was used to assist in crossing the CTO. IVUS revealed a ~5mm reference vessel populated with heavily calcified plaque (Figure 3B-C). Orbital atherectomy with a 1.25 micro crown at low/medium revolutions was performed and followed with a 2.0 solid crown at low, medium, and high revolutions. After prepping the vessel, PTA was performed with a 5mm x 100mm balloon, followed with a 6mm x 150mm Lutonix DCB, bringing the 100% stenosis to <10% (Figure 4).

Discussion

Endovascular treatment of the SFA remains challenging because of the high rates of restenosis. As we noted in case 1, the patient required re-interventions at her 5-month follow-up, highlighting the challenge of not only revascularizing a vessel, but also keeping the vessel patent in order to prevent life-limiting symptoms from re-emerging. The utility of drug-eluting technologies such as drug-coated balloons, direct drug delivery, and drug-eluting stents is promising and may lead to reduced restenosis rates. Prepping the vessel with the hope of improving drug deliverability and reducing the risk of dissection and elastic recoil is of utmost importance. Furthermore, the use of IVUS for visualizing the plaque morphology and adequately sizing the vessel allows interventionists to personalize their treatment. Identifying the plaque morphology plays a major role in charting the course of the intervention. In the above-mentioned cases, IVUS confirmed the plaque morphology to be heterogeneous or calcified, prompting prep of the vessel with orbital atherectomy prior to PTA. Plaque modification reduced the risk of a flow-limiting dissection and elastic recoil post balloon angioplasty.⁴ Flow-limiting dissections often require bail-out stenting, which is associated with diminished patency due to the in-stent restenosis process that continues to plague peripheral vascular intervention. Lastly, understanding the challenges of treating occlusive SFA disease will encourage operators to be well versed in the use of advanced techniques and a variety of devices to meet these challenges and improve patient outcomes. 

References

1. Roger VL, Go AS, Lloyd-Jones DM, Benjamin EJ, Berry JD, Borden WB, et al; American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Heart disease and stroke statistics--2012 update: a report from the American Heart Association. Circulation. 2012 Jan 3; 125(1): e2-e220. doi: 10.1161/CIR.0b013e31823ac046.
2. Laird JR, Katzen BT, Scheinert D, Lammer J, Carpenter J, Buchbinder M, et al; RESILIENT Investigators. Nitinol stent implantation versus balloon angioplasty for lesions in the superficial femoral artery and proximal popliteal artery: twelve-month results from the RESILIENT randomized trial. Circ Cardiovasc Interv. 2010 Jun 1; 3(3): 267-276. doi: 10.1161/CIRCINTERVENTIONS.109.903468.
3. Wood NB, Zhao SZ, Zambanini A, Jackson M, Gedroyc W, Thom SA, Hughes AD, Xu XY. Curvature and tortuosity of the superficial femoral artery: a possible risk factor for peripheral arterial disease. J Appl Physiol (1985). 2006 Nov; 101(5): 1412-1418.
4. Das T, Mustapha J, Indes J, Vorhies R, Beasley R, Doshi N, Adams GL. Technique optimization of orbital atherectomy in calcified peripheral lesions of the lower extremities: the CONFIRM series, a prospective multicenter registry. Catheter Cardiovasc Interv. 2014 Jan 1; 83(1): 115-122. doi: 10.1002/ccd.25046.

^aDepartment of Biomedical Engineering, North Carolina State University, Raleigh, North Carolina; ^bDirector of Cardiovascular and Peripheral Vascular Research, Rex Hospital – University of North Carolina Health System, Raleigh, North Carolina; ^cTampa, Florida

Disclosures: Dr. George Adams reports he is a consultant for Cook Medical, Daiichi Sankyo, Lake Region Medical, Volcano, Asahi, Abbott Vascular, CSI, Medtronic, and Terumo. He is a speaker for Abbott Vascular, CSI, Cook Medical, Medtronic, and Spectranetics. He has received research support from Boston Scientific, CloSys, Daiichi Sankyo, Flexible Stenting Solutions, Medtronic, Volcano, and Mercator. Dr. Vinayak Subramanian reports no conflicts of interest regarding the content herein. 

Orlando Marrero reports he is a consultant for Boston Scientific.

The authors can be contacted via Orlando Marrero, RCIS, MBA, at orlm8597@icloud.com.