Loeys–Dietz syndrome with aortic wall necrosis secondary to external wrapping

Loeys–Dietz syndrome with aortic wall necrosis secondary to external wrapping Abstract External aortic wrapping may overcompress the aortic wall. An 18-year-old man underwent valve-sparing aortic root replacement for annuloaortic ectasia caused by Loeys–Dietz syndrome. External Dacron graft wrapping was performed to protect the ascending aorta. A year later, he underwent mitral valve repair. Intraoperatively, after unwrapping the external graft, the wrapped ascending aortic wall appeared necrotic. Histopathology showed damaged smooth muscle cells in the adventitia and outer media with unaffected inner layers and an intact intimal surface. Ischaemic necrosis of the aortic wall was associated with arterial insufficiency secondary to overcompression of the aortic wall that was already weakened by Loeys–Dietz syndrome. We describe a patient with Loeys–Dietz syndrome in whom pathognomonic necrosis in the wrapped aortic wall was observed histopathologically. Loeys–Dietz syndrome, External wrapping, Necrotic aorta INTRODUCTION Although external aortic wrapping at a graft anastomotic site prevents bleeding and pseudoaneurysm formation [1], wrap-induced overcompression may cause ischaemia of the wrapped segment. We described a patient with Loeys–Dietz syndrome (LDS) in whom focal necrosis in the outer layers of the wrapped aorta was observed histopathologically [2]. CASE REPORT An 18-year-old man underwent valve-sparing aortic root replacement for annuloaortic ectasia secondary to LDS. Initial computed tomography (CT) revealed the diameter of the sinus of Valsalva, the ascending aorta and the aortic arch to be 45.0, 24.7 and 19.8 mm, respectively (Fig. 1A). The distal anastomotic site was externally wrapped using a Dacron graft (Gelweave, Vascutek, Austin, TX, USA) to prevent bleeding and rupture. A year later, mitral valve repair was performed for worsened mitral regurgitation. Preoperative CT revealed the diameter of his wrapped aorta and aortic arch to be 19.5 mm and 23.0 mm, respectively (Fig. 1B, Video 1). Intraoperatively, removal of the wrapping graft for cannulation revealed a necrotic ascending aorta (Fig. 1C) that caused aortic rupture, necessitating ascending aortic replacement. The unwrapped aortic arch was intact, and a 22-mm Dacron graft was anastomosed to the aortic arch. Figure 1: View largeDownload slide Computed tomography (CT) and intraoperative findings. (A) Initial CT image showing the aorta. Blue arrowheads show the sinus of Valsalva. (B) Post-VASRR CT image showing the wrapped ascending aorta (yellow arrows) and aortic arch (blue arrows). Yellow arrowheads show the distal anastomosis. (C) The ascending aorta after unwrapping of the external graft (blue arrowheads). Yellow arrows show the distal anastomotic site of the VSARR graft. The white arrow shows the initial cannulation site. VSARR: valve-sparing aortic root replacement. Figure 1: View largeDownload slide Computed tomography (CT) and intraoperative findings. (A) Initial CT image showing the aorta. Blue arrowheads show the sinus of Valsalva. (B) Post-VASRR CT image showing the wrapped ascending aorta (yellow arrows) and aortic arch (blue arrows). Yellow arrowheads show the distal anastomosis. (C) The ascending aorta after unwrapping of the external graft (blue arrowheads). Yellow arrows show the distal anastomotic site of the VSARR graft. The white arrow shows the initial cannulation site. VSARR: valve-sparing aortic root replacement. Histopathologically, the wrapped segment of the ascending aorta showed diffuse cell atrophy with loss of nuclei and cytoplasmic swelling in the smooth muscle cells of the adventitia and outer media (Fig. 2A), with an intact inner media and endothelium. We noted fragmented elastic fibres and cells of the media showing cystic spaces filled with mucoid material (Fig. 2B and C)—findings pathognomonic of LDS. Figure 2: View largeDownload slide Histopathological findings. (A) Haematoxylin–eosin stain showing the media (quadrangle of small window showing all aortic wall layers). Loss of nuclei and cytoplasmic swelling observed in the smooth muscle cells of the outer media. (B) Elastica van Gieson stain showing disorganization of the elastic fibres. (C) Toluidine blue stain shows mucopolysaccharide accumulation between the disrupted elastic fibres. A: adventitia; M: media; I: intima. Figure 2: View largeDownload slide Histopathological findings. (A) Haematoxylin–eosin stain showing the media (quadrangle of small window showing all aortic wall layers). Loss of nuclei and cytoplasmic swelling observed in the smooth muscle cells of the outer media. (B) Elastica van Gieson stain showing disorganization of the elastic fibres. (C) Toluidine blue stain shows mucopolysaccharide accumulation between the disrupted elastic fibres. A: adventitia; M: media; I: intima. Video 1: Post-VSARR computed tomography images. VSARR: valve-sparing aortic root replacement. Video 1: Post-VSARR computed tomography images. VSARR: valve-sparing aortic root replacement. Close His postoperative course was uneventful, and computed tomography revealed no pseudoaneurysm. DISCUSSION Aortic wall degeneration/erosion secondary to external wrap dislocation can complicate some cases [3]. We report the case of an LDS patient showing pathognomonic necrosis in the adventitia and outer media of the wrapped aorta. The aorta receives dual blood supply: the vasa vasorum nourishes the adventitia and outer two-thirds of the media, whereas direct diffusion of nutrients across the endothelium nourishes the inner media and intima [4]. External wrapping-induced compression of the vasa vasorum might have caused malperfusion of the vasa vasorum. On the basis of histopathology, we hypothesize that (i) LDS patients show a weak aortic wall secondary to damaged smooth muscle cells and elastic fibres. External wrapping might overcompress an already weakened aortic wall against the elasticity and high aortic pressure. (ii) Overcompression might cause insufficiency of the structurally weak vasa vasorum observed in LDS patients. Although we used a Dacron graft, a more microporous material that is permeable to fibroblasts and macrophages would have been a safer option for positive aortic remodelling [5]. When the patient was under treatment, external wrapping-induced overcompression caused necrosis and an increased risk of post-stenotic aortic arch dilatation; however, external wrapping-induced overcompression must be avoided. Moreover, external wrapping might be contraindicated in syndromic patients, including those with LDS. Because of a pre-existing fragile aortic wall, a concurrent ascending aortic replacement could have been performed (without an additional operative risk) rather than the external wrapping. CONCLUSION In conclusion, we report the case of a patient with LDS showing pathognomonic external wrapping-induced necrosis in the wrapped aorta. Conflict of interest: none declared. REFERENCES 1 Robicsek F , Daugherty HK , Mullen DC. External grafting of aortic aneurysms . J Thorac Cardiovasc Surg 1971 ; 61 : 131 – 4 . Google Scholar PubMed 2 Loeys BL , Chen J , Neptune ER , Judge DP , Podowski M , Holm T et al. A syndrome of altered cardiovascular, craniofacial, neurocognitive and skeletal development caused by mutations in TGFBR1 or TGFBR2 . Nat Genet 2005 ; 37 : 275 – 81 . Google Scholar CrossRef Search ADS PubMed 3 Neri E , Massetti M , Tanganelli P , Capannini G , Carone E , Tripodi A et al. Is it only a mechanical matter? Histologic modifications of the aorta underlying external banding . J Thorac Cardiovasc Surg 1999 ; 118 : 1116 – 8 . Google Scholar CrossRef Search ADS PubMed 4 Ritman EL , Lerman A. The dynamic vasa vasorum . Cardiovasc Res 2007 ; 75 : 649 – 58 . Google Scholar CrossRef Search ADS PubMed 5 Fujiwara H , Oda K , Saiki Y , Sakamoto N , Ohashi T , Sato M et al. The wrapping method using biodegradable felt strips has a preventive effect on the thinning of the aortic wall: experimental study in the canine aorta . J Vasc Surg 2006 ; 43 : 349 – 56 . Google Scholar CrossRef Search ADS PubMed © The Author(s) 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/about_us/legal/notices) http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png European Journal of Cardio-Thoracic Surgery Oxford University Press

Loeys–Dietz syndrome with aortic wall necrosis secondary to external wrapping

Loading next page...
 
/lp/ou_press/loeys-dietz-syndrome-with-aortic-wall-necrosis-secondary-to-external-dWxT0zwu5I
Publisher
Oxford University Press
Copyright
© The Author(s) 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
ISSN
1010-7940
eISSN
1873-734X
D.O.I.
10.1093/ejcts/ezx460
Publisher site
See Article on Publisher Site

Abstract

Abstract External aortic wrapping may overcompress the aortic wall. An 18-year-old man underwent valve-sparing aortic root replacement for annuloaortic ectasia caused by Loeys–Dietz syndrome. External Dacron graft wrapping was performed to protect the ascending aorta. A year later, he underwent mitral valve repair. Intraoperatively, after unwrapping the external graft, the wrapped ascending aortic wall appeared necrotic. Histopathology showed damaged smooth muscle cells in the adventitia and outer media with unaffected inner layers and an intact intimal surface. Ischaemic necrosis of the aortic wall was associated with arterial insufficiency secondary to overcompression of the aortic wall that was already weakened by Loeys–Dietz syndrome. We describe a patient with Loeys–Dietz syndrome in whom pathognomonic necrosis in the wrapped aortic wall was observed histopathologically. Loeys–Dietz syndrome, External wrapping, Necrotic aorta INTRODUCTION Although external aortic wrapping at a graft anastomotic site prevents bleeding and pseudoaneurysm formation [1], wrap-induced overcompression may cause ischaemia of the wrapped segment. We described a patient with Loeys–Dietz syndrome (LDS) in whom focal necrosis in the outer layers of the wrapped aorta was observed histopathologically [2]. CASE REPORT An 18-year-old man underwent valve-sparing aortic root replacement for annuloaortic ectasia secondary to LDS. Initial computed tomography (CT) revealed the diameter of the sinus of Valsalva, the ascending aorta and the aortic arch to be 45.0, 24.7 and 19.8 mm, respectively (Fig. 1A). The distal anastomotic site was externally wrapped using a Dacron graft (Gelweave, Vascutek, Austin, TX, USA) to prevent bleeding and rupture. A year later, mitral valve repair was performed for worsened mitral regurgitation. Preoperative CT revealed the diameter of his wrapped aorta and aortic arch to be 19.5 mm and 23.0 mm, respectively (Fig. 1B, Video 1). Intraoperatively, removal of the wrapping graft for cannulation revealed a necrotic ascending aorta (Fig. 1C) that caused aortic rupture, necessitating ascending aortic replacement. The unwrapped aortic arch was intact, and a 22-mm Dacron graft was anastomosed to the aortic arch. Figure 1: View largeDownload slide Computed tomography (CT) and intraoperative findings. (A) Initial CT image showing the aorta. Blue arrowheads show the sinus of Valsalva. (B) Post-VASRR CT image showing the wrapped ascending aorta (yellow arrows) and aortic arch (blue arrows). Yellow arrowheads show the distal anastomosis. (C) The ascending aorta after unwrapping of the external graft (blue arrowheads). Yellow arrows show the distal anastomotic site of the VSARR graft. The white arrow shows the initial cannulation site. VSARR: valve-sparing aortic root replacement. Figure 1: View largeDownload slide Computed tomography (CT) and intraoperative findings. (A) Initial CT image showing the aorta. Blue arrowheads show the sinus of Valsalva. (B) Post-VASRR CT image showing the wrapped ascending aorta (yellow arrows) and aortic arch (blue arrows). Yellow arrowheads show the distal anastomosis. (C) The ascending aorta after unwrapping of the external graft (blue arrowheads). Yellow arrows show the distal anastomotic site of the VSARR graft. The white arrow shows the initial cannulation site. VSARR: valve-sparing aortic root replacement. Histopathologically, the wrapped segment of the ascending aorta showed diffuse cell atrophy with loss of nuclei and cytoplasmic swelling in the smooth muscle cells of the adventitia and outer media (Fig. 2A), with an intact inner media and endothelium. We noted fragmented elastic fibres and cells of the media showing cystic spaces filled with mucoid material (Fig. 2B and C)—findings pathognomonic of LDS. Figure 2: View largeDownload slide Histopathological findings. (A) Haematoxylin–eosin stain showing the media (quadrangle of small window showing all aortic wall layers). Loss of nuclei and cytoplasmic swelling observed in the smooth muscle cells of the outer media. (B) Elastica van Gieson stain showing disorganization of the elastic fibres. (C) Toluidine blue stain shows mucopolysaccharide accumulation between the disrupted elastic fibres. A: adventitia; M: media; I: intima. Figure 2: View largeDownload slide Histopathological findings. (A) Haematoxylin–eosin stain showing the media (quadrangle of small window showing all aortic wall layers). Loss of nuclei and cytoplasmic swelling observed in the smooth muscle cells of the outer media. (B) Elastica van Gieson stain showing disorganization of the elastic fibres. (C) Toluidine blue stain shows mucopolysaccharide accumulation between the disrupted elastic fibres. A: adventitia; M: media; I: intima. Video 1: Post-VSARR computed tomography images. VSARR: valve-sparing aortic root replacement. Video 1: Post-VSARR computed tomography images. VSARR: valve-sparing aortic root replacement. Close His postoperative course was uneventful, and computed tomography revealed no pseudoaneurysm. DISCUSSION Aortic wall degeneration/erosion secondary to external wrap dislocation can complicate some cases [3]. We report the case of an LDS patient showing pathognomonic necrosis in the adventitia and outer media of the wrapped aorta. The aorta receives dual blood supply: the vasa vasorum nourishes the adventitia and outer two-thirds of the media, whereas direct diffusion of nutrients across the endothelium nourishes the inner media and intima [4]. External wrapping-induced compression of the vasa vasorum might have caused malperfusion of the vasa vasorum. On the basis of histopathology, we hypothesize that (i) LDS patients show a weak aortic wall secondary to damaged smooth muscle cells and elastic fibres. External wrapping might overcompress an already weakened aortic wall against the elasticity and high aortic pressure. (ii) Overcompression might cause insufficiency of the structurally weak vasa vasorum observed in LDS patients. Although we used a Dacron graft, a more microporous material that is permeable to fibroblasts and macrophages would have been a safer option for positive aortic remodelling [5]. When the patient was under treatment, external wrapping-induced overcompression caused necrosis and an increased risk of post-stenotic aortic arch dilatation; however, external wrapping-induced overcompression must be avoided. Moreover, external wrapping might be contraindicated in syndromic patients, including those with LDS. Because of a pre-existing fragile aortic wall, a concurrent ascending aortic replacement could have been performed (without an additional operative risk) rather than the external wrapping. CONCLUSION In conclusion, we report the case of a patient with LDS showing pathognomonic external wrapping-induced necrosis in the wrapped aorta. Conflict of interest: none declared. REFERENCES 1 Robicsek F , Daugherty HK , Mullen DC. External grafting of aortic aneurysms . J Thorac Cardiovasc Surg 1971 ; 61 : 131 – 4 . Google Scholar PubMed 2 Loeys BL , Chen J , Neptune ER , Judge DP , Podowski M , Holm T et al. A syndrome of altered cardiovascular, craniofacial, neurocognitive and skeletal development caused by mutations in TGFBR1 or TGFBR2 . Nat Genet 2005 ; 37 : 275 – 81 . Google Scholar CrossRef Search ADS PubMed 3 Neri E , Massetti M , Tanganelli P , Capannini G , Carone E , Tripodi A et al. Is it only a mechanical matter? Histologic modifications of the aorta underlying external banding . J Thorac Cardiovasc Surg 1999 ; 118 : 1116 – 8 . Google Scholar CrossRef Search ADS PubMed 4 Ritman EL , Lerman A. The dynamic vasa vasorum . Cardiovasc Res 2007 ; 75 : 649 – 58 . Google Scholar CrossRef Search ADS PubMed 5 Fujiwara H , Oda K , Saiki Y , Sakamoto N , Ohashi T , Sato M et al. The wrapping method using biodegradable felt strips has a preventive effect on the thinning of the aortic wall: experimental study in the canine aorta . J Vasc Surg 2006 ; 43 : 349 – 56 . Google Scholar CrossRef Search ADS PubMed © The Author(s) 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/about_us/legal/notices)

Journal

European Journal of Cardio-Thoracic SurgeryOxford University Press

Published: Dec 25, 2017

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off