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Haemodynamics and Flow Modification Stents for Peripheral Arterial Disease: A Review.

Kokkalis E, Aristokleous N, Houston JG - Ann Biomed Eng (2015)

Bottom Line: This secondary flow motion is lost in atheromatous disease and its re-introduction after endovascular treatment of PAD has been suggested as a method to induce stabilised and coherent haemodynamics.Stent designs able to generate spiral flow may support endothelial function and therefore increase patency rates.This review is focused on secondary flow phenomena in arteries and the development of flow modification stent technologies for the treatment of PAD.

View Article: PubMed Central - PubMed

Affiliation: Division of Cardiovascular and Diabetes Medicine, Ninewells Hospital and Medical School, University of Dundee, Mail Box 1, Dundee, DD1 9SY, United Kingdom.

ABSTRACT
Endovascular stents are widely used for the treatment of peripheral arterial disease (PAD). However, the development of in-stent restenosis and downstream PAD progression remain a challenge. Stent revascularisation of PAD causes arterial trauma and introduces abnormal haemodynamics, which initiate complicated biological processes detrimental to the arterial wall. The interaction between stent struts and arterial cells in contact, and the blood flow field created in a stented region, are highly affected by stent design. Spiral flow is known as a normal physiologic characteristic of arterial circulation and is believed to prevent the development of flow disturbances. This secondary flow motion is lost in atheromatous disease and its re-introduction after endovascular treatment of PAD has been suggested as a method to induce stabilised and coherent haemodynamics. Stent designs able to generate spiral flow may support endothelial function and therefore increase patency rates. This review is focused on secondary flow phenomena in arteries and the development of flow modification stent technologies for the treatment of PAD.

No MeSH data available.


Related in: MedlinePlus

(a) Spiral flow self-expanding stent prototype inserted in a testing tube. (b) Single spiral in the outflow of a spiral stent implanted in a cadaveric model; steady flow was used. (c–d) Single spiral and non-spiral flow in the outflow of a spiral and a control stent respectively, positioned in a flow phantom; steady flow was used. (e–f) Single spiral and non-spiral flow in the outflow of a spiral and a control stent respectively, implanted in porcine models; images were obtained at peak systole. (g) Contrast angiogram of spiral stent implanted in the right carotid artery of a pig; the red arrow indicates a visible part of the spiral inducer and the cross-section white line the ultrasound scan plane distal from the outflow of the stent.
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Fig4: (a) Spiral flow self-expanding stent prototype inserted in a testing tube. (b) Single spiral in the outflow of a spiral stent implanted in a cadaveric model; steady flow was used. (c–d) Single spiral and non-spiral flow in the outflow of a spiral and a control stent respectively, positioned in a flow phantom; steady flow was used. (e–f) Single spiral and non-spiral flow in the outflow of a spiral and a control stent respectively, implanted in porcine models; images were obtained at peak systole. (g) Contrast angiogram of spiral stent implanted in the right carotid artery of a pig; the red arrow indicates a visible part of the spiral inducer and the cross-section white line the ultrasound scan plane distal from the outflow of the stent.

Mentions: The re-introduction of naturally occurring spiral arterial flow in vascular grafts with improved clinical results and long-term safety at 5 years post implantation, has led to development of an arterial spiral inducing stent for the treatment of PAD. This device has a conventional cylindrical outside geometry, where a part of the stent struts form a spiral internal ridge, and it is covered with polytetrafluoroethylene (Fig. 4a). This spiral ridge is configured to drive the blood in a spiral flow pattern which is believed to protect the artery from restenosis and PAD progression.Figure 4


Haemodynamics and Flow Modification Stents for Peripheral Arterial Disease: A Review.

Kokkalis E, Aristokleous N, Houston JG - Ann Biomed Eng (2015)

(a) Spiral flow self-expanding stent prototype inserted in a testing tube. (b) Single spiral in the outflow of a spiral stent implanted in a cadaveric model; steady flow was used. (c–d) Single spiral and non-spiral flow in the outflow of a spiral and a control stent respectively, positioned in a flow phantom; steady flow was used. (e–f) Single spiral and non-spiral flow in the outflow of a spiral and a control stent respectively, implanted in porcine models; images were obtained at peak systole. (g) Contrast angiogram of spiral stent implanted in the right carotid artery of a pig; the red arrow indicates a visible part of the spiral inducer and the cross-section white line the ultrasound scan plane distal from the outflow of the stent.
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4764640&req=5

Fig4: (a) Spiral flow self-expanding stent prototype inserted in a testing tube. (b) Single spiral in the outflow of a spiral stent implanted in a cadaveric model; steady flow was used. (c–d) Single spiral and non-spiral flow in the outflow of a spiral and a control stent respectively, positioned in a flow phantom; steady flow was used. (e–f) Single spiral and non-spiral flow in the outflow of a spiral and a control stent respectively, implanted in porcine models; images were obtained at peak systole. (g) Contrast angiogram of spiral stent implanted in the right carotid artery of a pig; the red arrow indicates a visible part of the spiral inducer and the cross-section white line the ultrasound scan plane distal from the outflow of the stent.
Mentions: The re-introduction of naturally occurring spiral arterial flow in vascular grafts with improved clinical results and long-term safety at 5 years post implantation, has led to development of an arterial spiral inducing stent for the treatment of PAD. This device has a conventional cylindrical outside geometry, where a part of the stent struts form a spiral internal ridge, and it is covered with polytetrafluoroethylene (Fig. 4a). This spiral ridge is configured to drive the blood in a spiral flow pattern which is believed to protect the artery from restenosis and PAD progression.Figure 4

Bottom Line: This secondary flow motion is lost in atheromatous disease and its re-introduction after endovascular treatment of PAD has been suggested as a method to induce stabilised and coherent haemodynamics.Stent designs able to generate spiral flow may support endothelial function and therefore increase patency rates.This review is focused on secondary flow phenomena in arteries and the development of flow modification stent technologies for the treatment of PAD.

View Article: PubMed Central - PubMed

Affiliation: Division of Cardiovascular and Diabetes Medicine, Ninewells Hospital and Medical School, University of Dundee, Mail Box 1, Dundee, DD1 9SY, United Kingdom.

ABSTRACT
Endovascular stents are widely used for the treatment of peripheral arterial disease (PAD). However, the development of in-stent restenosis and downstream PAD progression remain a challenge. Stent revascularisation of PAD causes arterial trauma and introduces abnormal haemodynamics, which initiate complicated biological processes detrimental to the arterial wall. The interaction between stent struts and arterial cells in contact, and the blood flow field created in a stented region, are highly affected by stent design. Spiral flow is known as a normal physiologic characteristic of arterial circulation and is believed to prevent the development of flow disturbances. This secondary flow motion is lost in atheromatous disease and its re-introduction after endovascular treatment of PAD has been suggested as a method to induce stabilised and coherent haemodynamics. Stent designs able to generate spiral flow may support endothelial function and therefore increase patency rates. This review is focused on secondary flow phenomena in arteries and the development of flow modification stent technologies for the treatment of PAD.

No MeSH data available.


Related in: MedlinePlus