title: Postoperative rupture of an aortic aneurysmal dilation associated with a patent ductus arteriosus in a dog.
abstract: OBJECTIVE
  To describe an unusual case of fatal aortic aneurysm rupture after standard ligation of a left-to-right shunting patent ductus arteriosus (PDA) and review the literature concerning the causes of aneurysm and applicable medical physics of blood flow that may contribute to mural failure.
  
  
  METHODS
  Clinical case report.
  
  
  METHODS
  An 11-month-old female Brittany spaniel.
  
  
  RESULTS
  A PDA was diagnosed in the dog after referral for a grade IV/IV cardiac murmur. Diagnostic tests performed included a minimum database, thoracic radiography, and echocardiography. Conventional surgical ligation of the PDA was performed. The postoperative recovery from anesthesia was uneventful. Approximately 5 hours after surgery, the dog vocalized once and collapsed. All resuscitative efforts failed. Necropsy showed a large, spiral rupture of the cranial and dorsal wall of the aorta that extended from the left subclavian artery to 2 cm distal to the PDA-aorta junction. No evidence of intramural, perianeurysmal hemorrhage or inflammation was noted. Histopathologic examination of the ruptured aneurysm showed that the wall lacked a defined tunica intima and endothelial cell layer. A distinct separation of the thinned tunica media parallel to the elastic fibers was noted.
  
  
  CONCLUSIONS
  Dilatation of the aorta near the area of a PDA is one of the recognized abnormalities associated with the condition. Aneurysmal dilatation results from and contributes to abnormal blood flow dynamics and increased aortic wall tension, which promotes expansion. Although an unusual and previously unreported sequela, rupture of the aneurysm should be considered a possible complication when ligation of a PDA with a conspicuous aortic aneurysmal dilation is performed.
authors: Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, KS 66506-5606, USA.
authors: Dennis
authors: D
authors: Olsen
authors: Kenneth R
authors: KR
authors: Harkin
authors: Max N
authors: MN
authors: Banwell
authors: Gordon A
authors: GA
authors: Andrews
mesh_terms: D000818:Animals; D001019:Aortic Rupture / Q000209:etiology / Q000662:veterinary*; D004106:Dilatation / Q000009:adverse effects / Q000662:veterinary*; D004283:Dog Diseases / Q000000981:diagnostic imaging / Q000601:surgery*; D004285:Dogs; D004374:Ductus Arteriosus, Patent / Q000601:surgery / Q000662:veterinary*; D017809:Fatal Outcome; D005260:Female; D011183:Postoperative Complications / Q000662:veterinary; D011859:Radiography; D014463:Ultrasonography