Rapid Development of Multiple Pseudoaneurysms After Arterial Homograft Placement
A 52-year-old woman received a preserved aorto-bifemoral homograft to treat an infection of an aorto-bifemoral Dacron graft (Vascutek, Renfrewshire, Scotland) that was implanted 5 years ago. The infected graft was completely removed during the operation. Donor and recipient blood groups were matched. The donor was a 16-year-old boy who died after traumatic brain injury after a car accident. For organ preservation, University-of-Wisconsin solution (Viaspan, Bristol-Myers Squibb, Munich, Germany) was used. The arterial homograft was cryopreserved using a standardized freezing protocol. Immunosuppression was started 2 weeks after the operation and was maintained using the calcineurin inhibitor FK506 (1 mg/d).
After an uncomplicated recovery and discharge from the hospital, the patient rapidly developed multiple false aneurysms during the first 3 postoperative months (Figure 1). The aneurysms were detected during routine follow-up ultrasound. Two large pseudoaneurysms emerged at the level of central anastomosis, and 2 false saccular aneurysms developed on the right leg and 4 on the left leg of the homograft (Figure 2). The distal anastomoses remained intact. Because of imminent prosthetic graft reinfection, an endovascular repair approach was used; a unibody stent graft was implanted in combination with a femorofemoral crossover graft for revascularization of the left limb (Figure 2). The patient again recovered smoothly and both grafts remained patent. The histology resembled the typical pattern of arterial homograft degeneration, showing a prominent neointima formation and degenerated media (Figure 3).1 No signs of rejection were present. Therefore, the pseudoaneurysm development was attributed to fractures of the homograft after cryopreservation and thawing.2
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