Background/Rationale:

Guidelines for the management of peripheral artery diseases recommend endovascular therapy as a reasonable option for the treatment of femoropopliteal artery (FPA) lesions.^1,2 However, one of the potential challenges during endovascular procedures of FPA is the difficulty in achieving long-term patency and durability of the implanted stents, due to the unique anatomy and deformations of FPA during limb flexion.^3-5 Stenting of FPA may restrict the shortening capabilities of the artery, leading to kinking during leg flexion, which when coupled with stent fractures formed during leg flexion, may result in restenosis and reduced patency rates.^6,7

 One of the factors determining the extent of damage caused to the FPA and stent during endovascular procedures is the mechanical characteristics of the stent.⁸ Self-expanding nitinol stents have been proven to be a preferred choice over balloon expandable stents for treating FPA lesions due to their high radial strength and flexibility, reduced foreshortening, ability to recover after being crushed, and deployability without balloon dilation of the stent edge.⁹Nitinol is a highly elastic alloy with unique thermal-shape memory and mechanical properties that render it resilient and durable. Variations in the manufacturing processes of nitinol stents may affect the microstructure of the alloy, the stent design and subsequently the mechanical properties of the stents.⁸ Hence, different designs of self-expanding nitinol stents may affect limb flexion-induced deformations in the FPA in different ways.^10,11

 The SUPERA Peripheral Stent System is an interwoven self-expanding nitinol stent that has high flexibility, radial strength, and resistance to kinking and fractures.^12-14 The efficacy, safety and durability of SUPERA for the treatment of FPA lesions, including long and complex lesions, has been clinically proven in the SUPERB trial through 3 years of follow-up,^14,15 and other retrospective and prospective real-world studies.^16-23

 Although SUPERA has been available for commercial use in India for the last few years, nevertheless, there have been no studies till date, assessing the safety and effectiveness of SUPERA stent in Indian patients with FPA disease. The Indian clinical scenario for the management of peripheral vascular disease may be different from the West, due to low disease awareness, late presentation, delays in diagnosis, therapy cost and access issues, and lack of national registries.^24,25

 In view of this background, there is a crucial unmet need: (1) to understand the clinical presentation of FPA disease in patients with symptomatic lower extremity disease, and (2) to evaluate the safety and effectiveness outcomes of SUPERA stent in these patients in a real-world Indian scenario. Further, there is also a need to understand the various predicting factors for restenosis after endovascular treatment of FPA lesions, as literature is limited to very few studies outlining the role of lesion length and lesion severity in predicting outcomes after stenting of FPA lesions.^26-29

Study Design – Prospective, multicentre, non-interventional, observational, data collection registry 

Study Population - An estimated 500 eligible patients are planned to be enrolled from 25 centres across India  

 References:

1.      Aboyans V, Ricco JB, Bartelink MEL, et al. 2017 ESC guidelines on the diagnosis and treatment of peripheral arterial diseases, in collaboration with the European Society for Vascular Surgery (ESVS).Rev EspCardiol (Engl Ed). 2018;71(2):111. 

2.      Writing Committee Members, Gerhard-Herman MD, Gornik HL, Barrett C, et al. 2016 AHA/ACC Guideline on the management of patients with lower extremity peripheral artery disease: Executive summary: A report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines.Circulation. 2017;135(12):e686–e725.

3.      Bajzer CT. Arterial supply of the lower extremities. Available at: https://www.ncbi.nlm.nih.gov/books/NBK27342/. Accessed on: 12 Mar 2019.

4.      Watt JK. Origin of femoro-popliteal occlusions. Brit Med J.1965;2:1455-1459.

5.      Desyatova A, Poulson W, Deegan P, et al.Limb flexion-induced twist and associated intramural stresses in the human femoropopliteal artery. J R Soc Interface. 2017;14(128).

6.      Gökgöl C, Schumann S, Diehm N, et al.In vivo quantification of the deformations of the femoropopliteal segment: Percutaneous transluminal angioplasty vs nitinol stent placement. J EndovascTher. 2017;24(1):27-34.

7.      Scheinert D, Scheinert S, Sax J, et al.Prevalence and clinical impact of stent fractures after femoropopliteal stenting. J Am Coll Cardiol. 2005;45(2):312-5.

8.      Maleckis K, Anttila E, Aylward P, et al. Nitinol stents in the femoropopliteal artery: A mechanical perspective on material, design, and performance. Ann Biomed Eng. 2018;46(5):684-704.

9.      Mewissen MW. Primary nitinol stenting for femoropopliteal disease. J EndovascTher. 2009;16(2 Suppl 2):II63-81.

10.  MacTaggart J, Poulson W, Seas A, et al.Stent design affects femoropopliteal artery deformation. Ann Surg. 2018. doi: 10.1097/SLA.0000000000002747.

11.  Maleckis K, Deegan P, Poulson W, et al. Comparison of femoropopliteal artery stents under axial and radial compression, axialtension, bending, and torsion deformation. J Mech Behav Biomed Mater. 2017;75:160-168.

12.  SUPERA Instructions for Use. Available at: https://www.accessdata.fda.gov/cdrh_docs/pdf12/P120020c.pdf. Accessed on: 12 Mar 2019.

13.  Bishu K, Armstrong EJ. Supera self-expanding stents for endovascular treatment of femoropopliteal disease: A review of the clinical evidence. Vasc Health Risk Manag. 2015;11:387-95.

14.  Garcia L, Jaff MR, Metzger C, et al.Wire-interwoven nitinol stent outcome in the superficial femoral and proximal popliteal arteries: Twelve-month results of the SUPERB trial. Circ Cardiovasc Interv. 2015;8(5). pii: e000937.

15.  Garcia LA, Rosenfield KR, Metzger CD, et al.SUPERB final 3-year outcomes using interwoven nitinol biomimetic supera stent. Catheter Cardiovasc Interv. 2017;89(7):1259-1267.

16.  Brescia AA, Wickers BM, Correa JC, et al.Stenting of femoropopliteal lesions using interwoven nitinol stents.J Vasc Surg. 2015;61(6):1472-8.

17.  Myint M, Schouten O, Bourke V, et al. A real-world experience with the Supera interwoven nitinol stent in femoropopliteal arteries: Midterm patency results and failure analysis. J EndovascTher. 2016;23(3):433-41.

18.  Scheinert D, Grummt L, Piorkowski M, et al.A novel self-expanding interwoven nitinol stent for complex femoropopliteal lesions: 24-month results of the SUPERA SFA registry. J EndovascTher. 2011;18(6):745-52.

19.  Scheinert D, Werner M, Scheinert S, et al.Treatment of complex atherosclerotic popliteal artery disease with a new self-expanding interwoven nitinol stent: 12-month results of the Leipzig SUPERA popliteal artery stent registry. JACC Cardiovasc Interv. 2013;6(1):65-71. 

20.  Chan YC, Cheng SW, Ting AC, et al. Primary stenting of femoropopliteal atherosclerotic lesions using new helical interwoven nitinol stents. J Vasc Surg. 2014;59(2):384-91.

21.  Werner M, Paetzold A, Banning-Eichenseer U, et al.Treatment of complex atherosclerotic femoropopliteal artery disease with a self-expanding interwoven nitinol stent: Midterm results from the Leipzig SUPERA 500registry. EuroIntervention. 2014;10(7):861-8.

22.  León LR Jr, Dieter RS, Gadd CL, et al.Preliminary results of the initial United States experience with the Supera woven nitinol stent in the popliteal artery. J Vasc Surg. 2013;57(4):1014-22.

23.  Montero-Baker M, Ziomek GJ, Leon L, et al. Analysis of endovascular therapy for femoropopliteal disease with the Supera stent. JVasc Surg. 2016;64(4):1002-8.

24.  Sekar N. Education in vascular surgery: Critical issues in India. J Vasc Surg. 2008;48(6 Suppl):76S-80S.

25.  Suresh KR. What Ails diagnosis of peripheral arterial disease/critical limb ischemia/critical limb-threatening ischemia in India? Indian J Vasc&Endovasc Surg. 2017;4(4):139-142.

26.  Pearce BJ, Toursarkissian B. The current role of endovascular intervention in the management of diabetic peripheral arterial disease. Diabet Foot Ankle. 2012;3. doi: 10.3402/dfa.v3i0.18977.

27.  Chan YC, Cheng SW, Cheung GC.Predictors of restenosis in the use of helical interwoven nitinol stents to treat femoropopliteal occlusive disease. J Vasc Surg. 2015;62(5):1201-9.

28.  Park UJ, Kim HT, Roh YN.Factors affecting outcomes after endovascular treatment for femoropopliteal atherosclerotic lesions. Asian J Surg. 2019;42(1):209-216.

29.  Dohi T, Iida O, Soga Y, et al.Incidence, predictors, and prognosis of in-stent occlusion after endovascular treatmentwith nitinol stents for femoropopliteal lesions. J Vasc Surg. 2014;59(4):1009-1015.e1.