TY - JOUR
T1 - Thoracic endovascular stent grafting inhibits aortic growth
T2 - an experimental study
AU - Siegenthaler, Michael P.
AU - Celik, Ramazan
AU - Haberstroh, Joerg
AU - Bajona, Pietro
AU - Goebel, Heike
AU - Brehm, Kerstin
AU - Euringer, Wulf
AU - Beyersdorf, Friedhelm
N1 - Funding Information:
§Presented at the 21st Annual Meeting of the European Association for Cardio-thoracic Surgery, Geneva, Switzerland, September 16—19, 2007. §§ This study has been supported by a grant of Vascutek Ltd., Scotland. * Corresponding author. Address: Heart Lung Esophageal Surgery Institute, UPMC Presbyterian, Suite C-900 200 Lothrop Street, Pittsburgh, PA 15213, United States. Tel.: +1 412 648 6648; fax: +1 412 648 6356. E-mail address: siegenthlaermp@upmc.edu (M.P. Siegenthaler).
PY - 2008/7
Y1 - 2008/7
N2 - Objective: Dilatation of the aorta at the landing zone site may be exaggerated by the radial force of stent grafts potentially limiting long-term results of endovascular therapy. We evaluated growth patterns and morphology of the thoracic aorta in young piglets after thoracic stent-graft placement. Methods: Eight domestic piglets (37 ± 2 kg) had an endovascular stent graft placed in the proximal descending thoracic aorta using retroperitoneal access. At implantation, the stent was oversized by 10%. Aortic size was documented after thoracotomy by intraoperative measurement and angiography. Subsequently the piglets were grown to adult size (181 ± 42 kg). At explantation 6-15 months later, CT scan and surgical evaluation for endoleaks, defined as perigraft flow, was performed. Histopathological assessment of the explanted aorta was performed in stented and non-stented segments and compared to five normal porcine aortas. Results: No endoleak (perigraft flow) or stent migration occurred even in 230 kg pigs. The stent grafts expanded to full size, but there was no further growth in the stented area. The aortic diameter increased significantly by 32 ± 9% 1 cm proximal to the stents (p = 0.0012) and by 45 ± 13% 1 cm distal to the stents (p = 0.0033). The stented area grew less than the proximal (p = 0.0011) and distal aorta (p < 0.0001). In all pigs, the distal aorta was larger than the proximal overstented segment. Histology of the stented aorta showed significant thickening of the intima (p = 0.018) and media (p = 0.006) with neointimal formation and segmental fibrosis of the inner 1/3 of the media with loss of smooth muscle cells and compression of the elastic fibers but normal architecture in the outer 2/3 of the media. Conclusions: Endovascular stent grafting may inhibit growth of the nonatherosclerotic normal aorta and lead to intimal hyperplasia and focal fibrosis in the inner media part adjacent to the stent. Stent-graft interaction with aortic tissue over time is important and should receive more detailed evaluation. Testing this interaction in an animal model of nonatherosclerotic dilative aortic disease could be of great interest.
AB - Objective: Dilatation of the aorta at the landing zone site may be exaggerated by the radial force of stent grafts potentially limiting long-term results of endovascular therapy. We evaluated growth patterns and morphology of the thoracic aorta in young piglets after thoracic stent-graft placement. Methods: Eight domestic piglets (37 ± 2 kg) had an endovascular stent graft placed in the proximal descending thoracic aorta using retroperitoneal access. At implantation, the stent was oversized by 10%. Aortic size was documented after thoracotomy by intraoperative measurement and angiography. Subsequently the piglets were grown to adult size (181 ± 42 kg). At explantation 6-15 months later, CT scan and surgical evaluation for endoleaks, defined as perigraft flow, was performed. Histopathological assessment of the explanted aorta was performed in stented and non-stented segments and compared to five normal porcine aortas. Results: No endoleak (perigraft flow) or stent migration occurred even in 230 kg pigs. The stent grafts expanded to full size, but there was no further growth in the stented area. The aortic diameter increased significantly by 32 ± 9% 1 cm proximal to the stents (p = 0.0012) and by 45 ± 13% 1 cm distal to the stents (p = 0.0033). The stented area grew less than the proximal (p = 0.0011) and distal aorta (p < 0.0001). In all pigs, the distal aorta was larger than the proximal overstented segment. Histology of the stented aorta showed significant thickening of the intima (p = 0.018) and media (p = 0.006) with neointimal formation and segmental fibrosis of the inner 1/3 of the media with loss of smooth muscle cells and compression of the elastic fibers but normal architecture in the outer 2/3 of the media. Conclusions: Endovascular stent grafting may inhibit growth of the nonatherosclerotic normal aorta and lead to intimal hyperplasia and focal fibrosis in the inner media part adjacent to the stent. Stent-graft interaction with aortic tissue over time is important and should receive more detailed evaluation. Testing this interaction in an animal model of nonatherosclerotic dilative aortic disease could be of great interest.
KW - Descending thoracic aorta
KW - Endovascular stent
KW - Marfan syndrome
KW - Porcine aorta
KW - Type 1 endoleak
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U2 - 10.1016/j.ejcts.2008.03.045
DO - 10.1016/j.ejcts.2008.03.045
M3 - Article
C2 - 18485725
AN - SCOPUS:45549083855
SN - 1010-7940
VL - 34
SP - 17
EP - 24
JO - European Journal of Cardio-thoracic Surgery
JF - European Journal of Cardio-thoracic Surgery
IS - 1
ER -