Study Comparing Two Methods of Expanding Stents Placed in Legs of Diabetics With Peripheral Vascular Disease

PERIPHERAL VASCULAR DISEASE Clinical Trial

— COBRA  

Official title:

PolarCath® Cryoplasty Versus Conventional Balloon Post-dilation of Nitinol Stents for Peripheral Vascular Interventions (COBRA)

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00827853
• Other study ID #: BOSTON SCI R&E 9-21-07#2
• Status: Completed
• Phase: N/A
• First received: January 22, 2009
• Last updated: November 1, 2013
• Start date: November 2008
• Est. completion date: February 2012

Study information

• Verified date: November 2013
• Source: North Texas Veterans Healthcare System
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review BoardUnited States: Federal Government
• Study type: Interventional

Clinical Trial Summary

Despite recent advances in stent technology and its widespread application in the treatment of peripheral vascular disease (PVD), incidences of partial or complete blockage of stent lumen (in-stent restenosis) due to in growth of cells (neo-intimal proliferation) is unacceptably high.

In diabetics with long superficial femoral artery (SFA) lesions, in-stent restenosis rates are higher than in non-diabetics. Consequently interventional techniques that curtail in-stent restenosis have to be explored. Cryoplasty is a stent expansion method in which a balloon is expanded using pressurized nitrous oxide gas. As the nitrous oxide expands in the balloon it cools the surroundings to about -10 degrees C. This induces programed death (apoptosis) of the smooth muscle cells in arterial wall.

The investigators hypothesize that Cryoplasty, by inducing an apoptotic smooth muscle cell response, when applied to post-dilation of nitinol self-expanding stents in the Superficial Femoral Artery (SFA) of diabetics, would lead to decreased in-stent restenosis due to decreased neointimal proliferation.

Description:

The pre-recruitment process would identify diabetics who have life-style limiting claudication in their legs. Based on the physicians decision such patients may have to undergo a peripheral vascular intervention of the SFA, with placement of self-expanding nitinol stents. If such a decision is made, the patient will be randomized to either cryoplasty balloon post-dilation of the stent or to conventional angioplasty balloon post-dilation after obtaining informed consent. At one year, in segment (stent + 10 mm beyond its proximal and distal edges) peak systolic velocity by duplex ultrasound will be measured in all subjects to assess the rate of binary restenosis defined as a > or = 2.5 times increase in peak systolic velocity (primary endpoint). A 6 month resting ankle brachial index, and binary restenosis may be assessed as a secondary endpoint of the study.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 90
• Est. completion date: February 2012
• Est. primary completion date: August 2011
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 21 Years and older

Eligibility

Inclusion Criteria:

• Diabetics, insulin or non-insulin dependent above 21 years of age

• Able to provide an informed consent

• Life expectancy > 1 year

• Presenting with with moderate claudication (Rutherford stage 2), severe intermittent claudication (Rutherford stage 3), chronic critical limb ischemia with pain while the patient was at rest(Rutherford stage 4), or chronic critical limb ischemia with ischemic ulcers/gangrene(Rutherford stage 5/6)

• Placement of > 5 mm in diameter self-expanding Nitinol stent in the SFA, with at least 1 vessel infra-popliteal runoff

• Placement of > 60 mm in length self-expanding Nitinol stent in the SFA, with at least 1 vessel infra-popliteal runoff

Exclusion Criteria:

• Serum creatinine of >= 2.0 mg/dl

• Presence of iodinated contrast allergy

• Presence of allergy to Aspirin and Plavix

• Pregnancy

• Relative or absolute contraindication for anticoagulation

• History of allergy to Angiomax and unfractionated heparin or heparin induced thrombocytopenia (HIT)

• White blood count < 3000; platelet count < 100000, and baseline hemoglobin < 10 g/dl

• Absence of brisk at least 1 vessel infra-popliteal runoff to the foot

• Left ventricular ejection fraction < 25%

• Relative or absolute contraindication for anticoagulation

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Single Blind (Subject), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Peripheral Arterial Disease
• PERIPHERAL VASCULAR DISEASE
• Peripheral Vascular Diseases
• Vascular Diseases

Intervention

Procedure:
• Conventional angioplasty balloon
Post-dilation of clinically indicated nitinol self-expanding stents in the SFA using conventional angioplasty balloon
• cryoplasty balloon
Post-dilation of clinically indicated nitinol self-expanding stents in the SFA using cryoplasty balloon

Locations

Country	Name	City	State
United States	Dallas Presbyterian Hospital	Dallas	Texas
United States	Dallas Veterans Hospital	Dallas	Texas
United States	Midwest Cardiovascular Research Foundation	Davenport	Iowa
United States	VA Medical Center	Oklahoma City	Oklahoma

Sponsors (2)

Lead Sponsor	Collaborator
North Texas Veterans Healthcare System	Boston Scientific Corporation

Country where clinical trial is conducted

United States, 

References & Publications (14)

Becquemin JP, Favre JP, Marzelle J, Nemoz C, Corsin C, Leizorovicz A. Systematic versus selective stent placement after superficial femoral artery balloon angioplasty: a multicenter prospective randomized study. J Vasc Surg. 2003 Mar;37(3):487-94. — View Citation

Cejna M, Thurnher S, Illiasch H, Horvath W, Waldenberger P, Hornik K, Lammer J. PTA versus Palmaz stent placement in femoropopliteal artery obstructions: a multicenter prospective randomized study. J Vasc Interv Radiol. 2001 Jan;12(1):23-31. — View Citation

Duda SH, Pusich B, Richter G, Landwehr P, Oliva VL, Tielbeek A, Wiesinger B, Hak JB, Tielemans H, Ziemer G, Cristea E, Lansky A, Bérégi JP. Sirolimus-eluting stents for the treatment of obstructive superficial femoral artery disease: six-month results. Circulation. 2002 Sep 17;106(12):1505-9. — View Citation

Grassl ED, Bischof JC. In vitro model systems for evaluation of smooth muscle cell response to cryoplasty. Cryobiology. 2005 Apr;50(2):162-73. — View Citation

Johnston KW. Femoral and popliteal arteries: reanalysis of results of balloon angioplasty. Radiology. 1992 Jun;183(3):767-71. — View Citation

Laird J, Jaff MR, Biamino G, McNamara T, Scheinert D, Zetterlund P, Moen E, Joye JD. Cryoplasty for the treatment of femoropopliteal arterial disease: results of a prospective, multicenter registry. J Vasc Interv Radiol. 2005 Aug;16(8):1067-73. — View Citation

Minar E, Pokrajac B, Maca T, Ahmadi R, Fellner C, Mittlböck M, Seitz W, Wolfram R, Pötter R. Endovascular brachytherapy for prophylaxis of restenosis after femoropopliteal angioplasty : results of a prospective randomized study. Circulation. 2000 Nov 28;102(22):2694-9. — View Citation

Sabeti S, Mlekusch W, Amighi J, Minar E, Schillinger M. Primary patency of long-segment self-expanding nitinol stents in the femoropopliteal arteries. J Endovasc Ther. 2005 Feb;12(1):6-12. — View Citation

Sabeti S, Schillinger M, Amighi J, Sherif C, Mlekusch W, Ahmadi R, Minar E. Primary patency of femoropopliteal arteries treated with nitinol versus stainless steel self-expanding stents: propensity score-adjusted analysis. Radiology. 2004 Aug;232(2):516-21. — View Citation

Schillinger M, Exner M, Mlekusch W, Haumer M, Sabeti S, Ahmadi R, Schwarzinger I, Wagner O, Minar E. Restenosis after femoropopliteal PTA and elective stent implantation: predictive value of monocyte counts. J Endovasc Ther. 2003 Jun;10(3):557-65. — View Citation

Schillinger M, Sabeti S, Loewe C, Dick P, Amighi J, Mlekusch W, Schlager O, Cejna M, Lammer J, Minar E. Balloon angioplasty versus implantation of nitinol stents in the superficial femoral artery. N Engl J Med. 2006 May 4;354(18):1879-88. — View Citation

Venkatasubramanian RT, Grassl ED, Barocas VH, Lafontaine D, Bischof JC. Effects of freezing and cryopreservation on the mechanical properties of arteries. Ann Biomed Eng. 2006 May;34(5):823-32. Epub 2006 Apr 18. — View Citation

Yiu WK, Cheng SW, Sumpio BE. Vascular smooth muscle cell apoptosis induced by "supercooling" and rewarming. J Vasc Interv Radiol. 2006 Dec;17(12):1971-7. — View Citation

Zdanowski Z, Albrechtsson U, Lundin A, Jonung T, Ribbe E, Thörne J, Norgren L. Percutaneous transluminal angioplasty with or without stenting for femoropopliteal occlusions? A randomized controlled study. Int Angiol. 1999 Dec;18(4):251-5. — View Citation

* Note: There are 14 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Rate of binary restenosis as determined by duplex ultrasound.		1 year	No
Secondary	Resting ankle-brachial index		6 months and 1 year	No