Creation of reentry tears in aortic dissection by means of percutaneous balloon fenestration: gross anatomic and histologic considerations.

PURPOSE: To study the safety and efficacy of percutaneous fenestration in aortic dissection, transmural tears in canine and human aortae were created with conventional angioplasty balloons.
MATERIALS AND METHODS: Tears created in the aortae of five living dogs were compared with tears created in postmortem specimens. Percutaneous fenestration was performed in a woman with acute type I dissection and ischemic hepatitis who died in multisystem failure, and the balloon tear was documented at autopsy. Additional tears in the human aorta were studied in necropsy specimens of normal, Marfanoid, atherosclerotic, and acutely and chronically dissected thoracic and abdominal aortae.
RESULTS: In the canine aorta, transmural balloon tears resulted in rapid death of all five animals, and the tears were approximately 10% longer than tears created post mortem with the same balloon. In human aortic specimens, most transmural and all transseptal tears were linear and were oriented nearly perpendicular to the longitudinal axis of the aorta. Tears that were initiated near calcified plaques or large aortic branches extended in unpredictable directions. The transverse orientation of the tears coincided with the long axis of smooth muscle cells in the media of the intact aorta or the dissection septum.
CONCLUSION: Percutaneous balloon fenestration, when performed in areas of the aorta relatively free of atherosclerosis, results in transverse tears in the aortic dissection septum. Percutaneous fenestration of the aortic dissection septum appears feasible and should be considered as a treatment option in carefully selected cases of aortic dissection with ischemic complications. A final conclusion regarding the safety and efficacy of percutaneous fenestration undertaken to relieve organ ischemia requires further clinical experience.