Aneurysms due to intimomedial mucoid degeneration.

OBJECTIVE: Review management of patients presenting with aneurysms due to intimomedial mucoid degeneration (IMMD).

DESIGN: Retrospective analysis.

SETTING: Metropolitan Vascular Service, Departments of Haematology and Pathology, University of Natal.

MATERIALS AND METHODS: Case records reviewed over an 11 year period. Twenty-two patients were submitted for surgery. All had histological confirmation of disease. All patients were black African (Negro) descent and nineteen were female. Average age was 52 years.

RESULTS: Fifteen patients had involvement of descending aorta and seven patients had extra-aortic involvement. Hypertension was noted in half of the patients. Seven patients presented acutely with rupture (4) and ischaemic lower limbs due to dissection (3). Total absence of clot within aneurysm lumen was a distinctive finding on ultrasound, CT-scan and angiography. Treatment followed standard vascular surgical principles. Three patients died following emergency aortic replacement. Three patients developed severe intraoperative bleeding problems following elective aortic aneurysm resection due to primary fibrinolysis. All had normal preoperative coagulation profiles.

CONCLUSION: IMMD is a rare disease affecting the intima and media of vessel wall involving aortic and extra aortic vessels, predominantly in younger African females with hypertension. Lack of clot within aneurysm lumen should alert surgeon to predisposition toward bleeding diathesis. Meticulous suture technique is essential as aortic wall is friable. Medium to long term results are satisfactory.