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Disruption of the Vascular Prosthesis Caused by Aortic Calcification After Replacement of the Thoracoabdominal Aortic Aneurysm

2006; Elsevier BV; Volume: 82; Issue: 3 Linguagem: Inglês

10.1016/j.athoracsur.2006.01.040

1552-6259

Hiroshi Tanaka, Kenji Okada, Teruo Yamashita, Yujiro Kawanishi, Masamiti Matsumori, Yutaka Okita,

Cardiac Valve Diseases and Treatments

A 52-year-old man underwent a replacement of the thoracoabdominal aorta. The aorta was severely calcified, and was replaced by a 24-mm woven Dacron (Vascutek, Renfrewshire, Scotland) graft wrapped with the calcificated aneurysmal wall. His postoperative course was uneventful; however, he collapsed on the 18th postoperative day. He underwent an emergent thoracotomy and the wrapped aneurysmal wall was taken down. The prosthesis graft had a 1-mm disruption in the middle portion, which did not relate to the anastomoses. Experimental study ex vivo showed that disruption of the prosthesis could have occurred after a 3-week pulsatile force caused by a seashell simulating aortic calcification. A 52-year-old man underwent a replacement of the thoracoabdominal aorta. The aorta was severely calcified, and was replaced by a 24-mm woven Dacron (Vascutek, Renfrewshire, Scotland) graft wrapped with the calcificated aneurysmal wall. His postoperative course was uneventful; however, he collapsed on the 18th postoperative day. He underwent an emergent thoracotomy and the wrapped aneurysmal wall was taken down. The prosthesis graft had a 1-mm disruption in the middle portion, which did not relate to the anastomoses. Experimental study ex vivo showed that disruption of the prosthesis could have occurred after a 3-week pulsatile force caused by a seashell simulating aortic calcification. Disruption of implanted modern vascular prostheses has not been reported in the recent era, although some reports showed anastomotic disruption caused by infection. This is a first case report that describes the mechanical force in vivo caused by aortic calcification that could make a hole in modern vascular prostheses.A 52-year-old man with a thoracoabdominal aneurysm was referred for surgery. He had chronic renal failure and had undergone dialysis 3 times a week for 8 years. Chest computed tomography showed severe calcification of the entire aortic wall (Fig 1). He underwent replacement of the thoracoabdominal aorta using a 24-mm woven Dacron graft (Gelseal, Vascutek) with reconstruction of visceral arteries and intercostal arteries using a partial cardiopulmonary bypass. After completion of the anastomoses, the graft was wrapped with the calcified aneurysmal wall. The postoperative course was uneventful; however, he collapsed in the ward on the 18th postoperative day. He was immediately resuscitated and a chest roentgenogram showed a massive left hemothorax. He underwent an emergent thoracotomy, and the calcified aneurysmal wall covering the graft was taken down. The prosthesis graft had a 1-mm hole in the middle portion that was unrelated to the anastomoses or the prosthesis branches (Fig 2). The graft was repaired with a 3-0 Prolene (Ethicon, Somerville, NJ) buttress suture. He was able to return to his normal life.Fig 2At the emergent re-thoracotomy, the implanted vascular prosthesis had a hole that did not relate to the anastomoses.View Large Image Figure ViewerDownload (PPT)CommentSome cases of disruption of the vascular graft prosthesis have been reported, and most reports demonstrate disruption related to anastomoses with or without infection [1Wilson S.E. Krug R. Mueller G. Late Disruption of Dacron aortic grafts.Ann Vasc Surg. 1997; 11: 383-386Abstract Full Text PDF PubMed Scopus (38) Google Scholar]. In our case, we presumed that the graft was disrupted resulting from pulsatile force caused by a severely calcified aortic wall that wrapped the graft, and we implemented an ex vivo experimental study to investigate the durability of the prosthesis.An 18-mm woven Dacron vascular prosthesis graft (Gelseal, Vascutek) that was the same as the disrupted graft was placed into a 24-mm acryl tube that was glued inside four fragments of shell (Megangulus venulosa) to simulate the aortic calcification, in a 37°C tank (Fig 3). Pulsatile pressure was made inside the graft by compressed air using a programmable valve that was 80 bpm and 80 to 160 mm Hg, according to the Food and Drug Administration Guidance [2Center for devices and radiological health. Food and Drug Administration guidance for the preparation of research and marketing application for vascular graft prostheses, 1993.Google Scholar], for a period of 21 days. Three grafts were examined; two of the grafts were disrupted on the 10th day, with ruptures of the Dacron fiber visible under a microscope. Another graft was disrupted on the 18th day, with ruptured fiber and frayed spots identified (Fig 4).Fig 3An 18-mm woven Dacron vascular prosthesis graft that was the same as the disrupted graft was placed into a 24-mm acryl tube that was glued inside fragments of shell (Megangulus venulosa) that simulated the aortic calcification in a 37°C tank.View Large Image Figure ViewerDownload (PPT)Fig 4The vascular graft examined was disrupted on the 18th day with ruptured fiber and frayed spots identified.View Large Image Figure ViewerDownload (PPT)We conclude that woven Dacron grafts for vascular surgery could be disrupted by pulsatile force caused by aortic calcification during a period of only a few weeks. Disruption of implanted modern vascular prostheses has not been reported in the recent era, although some reports showed anastomotic disruption caused by infection. This is a first case report that describes the mechanical force in vivo caused by aortic calcification that could make a hole in modern vascular prostheses. A 52-year-old man with a thoracoabdominal aneurysm was referred for surgery. He had chronic renal failure and had undergone dialysis 3 times a week for 8 years. Chest computed tomography showed severe calcification of the entire aortic wall (Fig 1). He underwent replacement of the thoracoabdominal aorta using a 24-mm woven Dacron graft (Gelseal, Vascutek) with reconstruction of visceral arteries and intercostal arteries using a partial cardiopulmonary bypass. After completion of the anastomoses, the graft was wrapped with the calcified aneurysmal wall. The postoperative course was uneventful; however, he collapsed in the ward on the 18th postoperative day. He was immediately resuscitated and a chest roentgenogram showed a massive left hemothorax. He underwent an emergent thoracotomy, and the calcified aneurysmal wall covering the graft was taken down. The prosthesis graft had a 1-mm hole in the middle portion that was unrelated to the anastomoses or the prosthesis branches (Fig 2). The graft was repaired with a 3-0 Prolene (Ethicon, Somerville, NJ) buttress suture. He was able to return to his normal life. CommentSome cases of disruption of the vascular graft prosthesis have been reported, and most reports demonstrate disruption related to anastomoses with or without infection [1Wilson S.E. Krug R. Mueller G. Late Disruption of Dacron aortic grafts.Ann Vasc Surg. 1997; 11: 383-386Abstract Full Text PDF PubMed Scopus (38) Google Scholar]. In our case, we presumed that the graft was disrupted resulting from pulsatile force caused by a severely calcified aortic wall that wrapped the graft, and we implemented an ex vivo experimental study to investigate the durability of the prosthesis.An 18-mm woven Dacron vascular prosthesis graft (Gelseal, Vascutek) that was the same as the disrupted graft was placed into a 24-mm acryl tube that was glued inside four fragments of shell (Megangulus venulosa) to simulate the aortic calcification, in a 37°C tank (Fig 3). Pulsatile pressure was made inside the graft by compressed air using a programmable valve that was 80 bpm and 80 to 160 mm Hg, according to the Food and Drug Administration Guidance [2Center for devices and radiological health. Food and Drug Administration guidance for the preparation of research and marketing application for vascular graft prostheses, 1993.Google Scholar], for a period of 21 days. Three grafts were examined; two of the grafts were disrupted on the 10th day, with ruptures of the Dacron fiber visible under a microscope. Another graft was disrupted on the 18th day, with ruptured fiber and frayed spots identified (Fig 4).Fig 4The vascular graft examined was disrupted on the 18th day with ruptured fiber and frayed spots identified.View Large Image Figure ViewerDownload (PPT)We conclude that woven Dacron grafts for vascular surgery could be disrupted by pulsatile force caused by aortic calcification during a period of only a few weeks. Some cases of disruption of the vascular graft prosthesis have been reported, and most reports demonstrate disruption related to anastomoses with or without infection [1Wilson S.E. Krug R. Mueller G. Late Disruption of Dacron aortic grafts.Ann Vasc Surg. 1997; 11: 383-386Abstract Full Text PDF PubMed Scopus (38) Google Scholar]. In our case, we presumed that the graft was disrupted resulting from pulsatile force caused by a severely calcified aortic wall that wrapped the graft, and we implemented an ex vivo experimental study to investigate the durability of the prosthesis. An 18-mm woven Dacron vascular prosthesis graft (Gelseal, Vascutek) that was the same as the disrupted graft was placed into a 24-mm acryl tube that was glued inside four fragments of shell (Megangulus venulosa) to simulate the aortic calcification, in a 37°C tank (Fig 3). Pulsatile pressure was made inside the graft by compressed air using a programmable valve that was 80 bpm and 80 to 160 mm Hg, according to the Food and Drug Administration Guidance [2Center for devices and radiological health. Food and Drug Administration guidance for the preparation of research and marketing application for vascular graft prostheses, 1993.Google Scholar], for a period of 21 days. Three grafts were examined; two of the grafts were disrupted on the 10th day, with ruptures of the Dacron fiber visible under a microscope. Another graft was disrupted on the 18th day, with ruptured fiber and frayed spots identified (Fig 4). We conclude that woven Dacron grafts for vascular surgery could be disrupted by pulsatile force caused by aortic calcification during a period of only a few weeks.