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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

Delivery device with guidewire (a), hydrogel (b), occlusion balloon (c), and delivery sheath (d)
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Fig1: Delivery device with guidewire (a), hydrogel (b), occlusion balloon (c), and delivery sheath (d)

Mentions: The Ethical Committee for animal experiments at the KU Leuven approved the experimentation (number P144-2010). Hydrogel cylinders (Ø3 mm × 15 mm) were implanted in the carotid artery of three sheep in a minimal invasive way. The sheep were sedated with intramuscular injection of ketamine (15 mg/kg). Anaesthesia was induced with isoflurane 5 %, the animal was intubated and an oral-gastric tube was placed. Anaesthesia was maintained with isoflurane (2–4 %). An intravenous line and arterial line in both ears were inserted. Heart rate, blood pressure, end-tidal CO2, and blood O2 saturation were constantly monitored. The left side of the neck was shaved. The carotid artery was isolated proximal and distal from the intended implant site of the hydrogel. Flow measurements were performed using a Doppler-flow probe. Heparine (100 U/kg) was administered before sheath placement. Proximal a 4 Fr sheath was placed for pressure measurement and angiography. Distally an 11 Fr sheath was placed for hydrogel delivery and pressure measurements. The delivery system, as shown in Fig. 1, consisted of a 9 Fr conventional sheath, straight 0.014-inch guidewire, and an occlusion balloon. After reaching the target destination, the occlusion balloon was inflated. Angiography was used every ten minutes to assess the occlusion status. After obtaining occlusion all attributes used for the implantation procedure were removed and a final angiography, pressure-, and flow measurement were performed. The sheaths were retracted and the puncture side of the carotid artery was closed with stiches. The incisions were closed in layers.Fig. 1


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)

Delivery device with guidewire (a), hydrogel (b), occlusion balloon (c), and delivery sheath (d)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

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

Fig1: Delivery device with guidewire (a), hydrogel (b), occlusion balloon (c), and delivery sheath (d)
Mentions: The Ethical Committee for animal experiments at the KU Leuven approved the experimentation (number P144-2010). Hydrogel cylinders (Ø3 mm × 15 mm) were implanted in the carotid artery of three sheep in a minimal invasive way. The sheep were sedated with intramuscular injection of ketamine (15 mg/kg). Anaesthesia was induced with isoflurane 5 %, the animal was intubated and an oral-gastric tube was placed. Anaesthesia was maintained with isoflurane (2–4 %). An intravenous line and arterial line in both ears were inserted. Heart rate, blood pressure, end-tidal CO2, and blood O2 saturation were constantly monitored. The left side of the neck was shaved. The carotid artery was isolated proximal and distal from the intended implant site of the hydrogel. Flow measurements were performed using a Doppler-flow probe. Heparine (100 U/kg) was administered before sheath placement. Proximal a 4 Fr sheath was placed for pressure measurement and angiography. Distally an 11 Fr sheath was placed for hydrogel delivery and pressure measurements. The delivery system, as shown in Fig. 1, consisted of a 9 Fr conventional sheath, straight 0.014-inch guidewire, and an occlusion balloon. After reaching the target destination, the occlusion balloon was inflated. Angiography was used every ten minutes to assess the occlusion status. After obtaining occlusion all attributes used for the implantation procedure were removed and a final angiography, pressure-, and flow measurement were performed. The sheaths were retracted and the puncture side of the carotid artery was closed with stiches. The incisions were closed in layers.Fig. 1

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