Experimental confirmation of effectiveness of fenestration in acute aortic dissection

Background. Aortic fenestration is used clinically to treat organ ischemia in acute descending aortic dissection. However, fenestration has not been studied experimentally. This study does so using an animal model. Methods. Descending aortic dissection was created in six dogs, with subsequent fenestration of the infrarenal aorta. Blood flow (femoral, cephalic, and renal), blood pressure (femoral and carotid), and aortic distensibility were measured at baseline, after dissection, and after fenestration. Values were compared using paired t tests. Results. Baseline femoral, cephalic, and renal arterial flows were 53 ± 37, 78 ± 65, and 83 ± 52 mL/min, respectively. Baseline femoral and carotid pressures were 82 ± 13 and 81 ± 11 mm Hg, respectively. After dissection, femoral, cephalic, and renal arterial flow decreased to 20 ± 21 (p< 0.05), 38 ± 26, and 56 ± 36 mL/min, respectively. Femoral blood pressure decreased to 28 ± 17 mm Hg (p< 0.05). With fenestration, femoral, cephalic, and renal flows increased to 60 ± 37 (p< 0.05), 78 ± 51, and 80 ± 48 mL/min, respectively. Femoral blood pressure increased to 85 ± 28 mm Hg (p< 0.05). Carotid pressure remained unchanged with dissection and fenestration (77 ± 17 mm Hg, 82 ± 17 mm Hg, respectively). Baseline aortic distensibility (21%) decreased significantly after dissection (to 1.4%, p< 0.05) and increased after fenestration (to 12%, p< 0.05). Conclusions. Experimental aortic fenestration restored blood pressure and flow to hypoperfused organs in acute descending aortic dissection. The continued clinical application of fenestration is supported.