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An electro-responsive hydrogel for intravascular applications: an in vitro and in vivo evaluation.

Verbrugghe P, Verhoeven J, Coudyzer W, Verbeken E, Dubruel P, Mendes E, Stam F, Meuris B, Herijgers P - J Mater Sci Mater Med (2015)

Bottom Line: Minimal invasive implantation in the carotid artery of sheep was used to evaluate its medium-term biological effects, through biochemical, macroscopic, radiographic, and microscopic evaluation.Indirect and direct testing of the material gave no indication of the haemolytic effects of the material.Evaluation at time of autopsy showed a persistent occlusion with no systemic effects, no signs of embolization and mild effects on the arterial wall.

View Article: PubMed Central - PubMed

Affiliation: Department of Cardiac Surgery, UZ Leuven, Herestraat 49, 3000, Louvain, Belgium. peter.verbrugghe@uzleuven.be.

ABSTRACT
There is a growing interest in using hydrogels for biomedical applications, because of more favourable characteristics. Some of these hydrogels can be activated by using particular stimuli, for example electrical fields. These stimuli can change the hydrogel shape in a predefined way. It could make them capable of adaptation to patient-specific anatomy even post-implantation. This is the first paper aiming to describe in vivo studies of an electro-responsive, Pluronic F127 based hydrogel, for intravascular applications. Pluronic methacrylic acid hydrogel (PF127/MANa) was in vitro tested for its haemolytic and cytotoxic effects. Minimal invasive implantation in the carotid artery of sheep was used to evaluate its medium-term biological effects, through biochemical, macroscopic, radiographic, and microscopic evaluation. Indirect and direct testing of the material gave no indication of the haemolytic effects of the material. Determination of fibroblast viability after 24 h of incubation in an extract of the hydrogel showed no cytotoxic effects. Occlusion was obtained within 1 h following in vivo implantation. Evaluation at time of autopsy showed a persistent occlusion with no systemic effects, no signs of embolization and mild effects on the arterial wall. An important proof-of-concept was obtained showing biocompatibility and effectiveness of a pluronic based electro-responsive hydrogel for obtaining an arterial occlusion with limited biological impact. So the selected pluronic-methacrylic acid based hydrogel can be used as an endovascular occlusion device. More importantly it is the first step in further development of electro-active hydrogels for a broad range of intra-vascular applications (e.g. system to prevent endoleakage in aortic aneurysm treatment, intra-vascular drug delivery).

No MeSH data available.


Related in: MedlinePlus

Photographs of the explanted carotid arteries. Thrombi can be seen proximal and distal from the place where the hydrogel has been. In sheep 1178 there were two vertical cracks (yellow arrow), in sheep 1172 there were thrombi at the vessel wall (white arrow) and an ulcer (blue arrow) (Color figure online)
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Fig5: Photographs of the explanted carotid arteries. Thrombi can be seen proximal and distal from the place where the hydrogel has been. In sheep 1178 there were two vertical cracks (yellow arrow), in sheep 1172 there were thrombi at the vessel wall (white arrow) and an ulcer (blue arrow) (Color figure online)

Mentions: Macroscopic evaluation, at time of explantation, showed an intact carotid artery. There were no firm adhesions of the vessel to its surrounding. Mild adhesions were seen a distance away from the hydrogels at the dissection and sheath insertion locations. The hydrogels were not attached to the vessel wall and fell out when the vessel was opened. There were small thrombi adjacent to both sides of the hydrogel (Fig. 5). Around the hydrogel there was a remarkable thrombus in one of the sheep (ID: 1172). Macroscopic evaluation of the vascular wall showed impairments in two of the sheep. In sheep 1178 there were two radial cracks, and in sheep 1172 there was a deep ulcer at the distal side of the hydrogel. Full autopsy could not reveal any sign of embolization, infarction, nor bleeding in the organs.Fig. 5


An electro-responsive hydrogel for intravascular applications: an in vitro and in vivo evaluation.

Verbrugghe P, Verhoeven J, Coudyzer W, Verbeken E, Dubruel P, Mendes E, Stam F, Meuris B, Herijgers P - J Mater Sci Mater Med (2015)

Photographs of the explanted carotid arteries. Thrombi can be seen proximal and distal from the place where the hydrogel has been. In sheep 1178 there were two vertical cracks (yellow arrow), in sheep 1172 there were thrombi at the vessel wall (white arrow) and an ulcer (blue arrow) (Color figure online)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4608972&req=5

Fig5: Photographs of the explanted carotid arteries. Thrombi can be seen proximal and distal from the place where the hydrogel has been. In sheep 1178 there were two vertical cracks (yellow arrow), in sheep 1172 there were thrombi at the vessel wall (white arrow) and an ulcer (blue arrow) (Color figure online)
Mentions: Macroscopic evaluation, at time of explantation, showed an intact carotid artery. There were no firm adhesions of the vessel to its surrounding. Mild adhesions were seen a distance away from the hydrogels at the dissection and sheath insertion locations. The hydrogels were not attached to the vessel wall and fell out when the vessel was opened. There were small thrombi adjacent to both sides of the hydrogel (Fig. 5). Around the hydrogel there was a remarkable thrombus in one of the sheep (ID: 1172). Macroscopic evaluation of the vascular wall showed impairments in two of the sheep. In sheep 1178 there were two radial cracks, and in sheep 1172 there was a deep ulcer at the distal side of the hydrogel. Full autopsy could not reveal any sign of embolization, infarction, nor bleeding in the organs.Fig. 5

Bottom Line: Minimal invasive implantation in the carotid artery of sheep was used to evaluate its medium-term biological effects, through biochemical, macroscopic, radiographic, and microscopic evaluation.Indirect and direct testing of the material gave no indication of the haemolytic effects of the material.Evaluation at time of autopsy showed a persistent occlusion with no systemic effects, no signs of embolization and mild effects on the arterial wall.

View Article: PubMed Central - PubMed

Affiliation: Department of Cardiac Surgery, UZ Leuven, Herestraat 49, 3000, Louvain, Belgium. peter.verbrugghe@uzleuven.be.

ABSTRACT
There is a growing interest in using hydrogels for biomedical applications, because of more favourable characteristics. Some of these hydrogels can be activated by using particular stimuli, for example electrical fields. These stimuli can change the hydrogel shape in a predefined way. It could make them capable of adaptation to patient-specific anatomy even post-implantation. This is the first paper aiming to describe in vivo studies of an electro-responsive, Pluronic F127 based hydrogel, for intravascular applications. Pluronic methacrylic acid hydrogel (PF127/MANa) was in vitro tested for its haemolytic and cytotoxic effects. Minimal invasive implantation in the carotid artery of sheep was used to evaluate its medium-term biological effects, through biochemical, macroscopic, radiographic, and microscopic evaluation. Indirect and direct testing of the material gave no indication of the haemolytic effects of the material. Determination of fibroblast viability after 24 h of incubation in an extract of the hydrogel showed no cytotoxic effects. Occlusion was obtained within 1 h following in vivo implantation. Evaluation at time of autopsy showed a persistent occlusion with no systemic effects, no signs of embolization and mild effects on the arterial wall. An important proof-of-concept was obtained showing biocompatibility and effectiveness of a pluronic based electro-responsive hydrogel for obtaining an arterial occlusion with limited biological impact. So the selected pluronic-methacrylic acid based hydrogel can be used as an endovascular occlusion device. More importantly it is the first step in further development of electro-active hydrogels for a broad range of intra-vascular applications (e.g. system to prevent endoleakage in aortic aneurysm treatment, intra-vascular drug delivery).

No MeSH data available.


Related in: MedlinePlus