J Korean Soc Radiol.  2010 Dec;63(6):513-518.

Risk Factors and Clinical Evaluation of Superficial Femoral Artery Stent Fracture: Protege GPS Stent

• Lee D
• Kim JK
• Jung HD
• Huh TW
• Yim NY
• Oh HJ
• Chang NK
• Choi SJ

Abstract

PURPOSE
To evaluate the occurrence of superficial femoral artery stent fractures, the risk factors of stent fracture, and the relationship between fractures and clinical findings.
MATERIALS AND METHODS
Of the 38 patients who underwent treatment with Protege GPS stenting due to arterial occlusions on the superficial femoral artery, 17 also underwent a clinical analysis. Forty-three stents were inserted in the 17 superficial femoral arteries, ranging between 15 and 50 cm in length, with a mean treated length of 26.4 cm (15-50 cm). A fracture was evaluated by taking a PA and lateral simple radiography, as well as a follow-up evaluation accompanied with a CT angiography, DSA, and a color Doppler sonography. The examination involved the assessment of the difference between bone fractures due to length, placement, and frequency.
RESULTS
Fractures occurred in 13 of 43 stents (30.2%). A total of 10 (71.4%) occurred in the upper third, compared to 4 (28.6%) in the lower third of the superficial femoral artery. In addition, 10 stents (71.4%) had a single strut fracture, whereas 4 (28.6%) had multiple strut fractures. A stent fracture occurred more frequently when the stents and lesions were longer (p=0.021, 0.012) and the stents were inserted near the joint. However, there was no significant relationship between stent numbers and the fractures (p=0.126). When the stents were inserted along the popliteal artery, a stent fracture occurred more frequently in the lower third of the artery. The stent fractures did not significantly influence the patency rate of the stented artery (p=0.44).
CONCLUSION
Protege GPS stents in the superficial femoral artery revealed a considerable number of fractures and the fracture frequency showed a significant relationship with the length of stents and lesions. The closer stent insertion was to the joints, the more frequently fractures occurred. There were no evident significant relationships between the presence of stent fractures and the patency of the stented arteries.

MeSH Terms

Angiography
Arteries
Arteriosclerosis
Femoral Artery
Follow-Up Studies
Fractures, Bone
Humans
Joints
Peripheral Arterial Disease
Popliteal Artery
Risk Factors
Stents

Figure

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  Fig. 1 Nitinol stent fracture classification system from cardiovascular institute of the south (7).

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  Fig. 2 64-year-old man with right leg claudication. A. Type I single fracture (arrow) occur at overlapping zone in the proximal superficial femoral artery 5 months after impantation. B. Note the reocclusion of the superficial femoral artery.

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  Fig. 3 A, B. 72-year-old man with type I and II stent fractures (arrows) with total occlusion of SFA at 16 months after placement of four stents in the SFA and the popliteal artery. C, D. After balloon angioplasty (arrows) following thrombolysis with infusion of UK 240,000 U, SFA is recanalized with residual stenosis.

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  Fig. 4 Primary stent patency rates for fractured and non-fractured stents (p=0.440).

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