UNRAVELING THE FAMILIAL TENDENCY TO ANEURYSMAL DISEASE - POPLITEAL ANEURYSM, HYPERTENSION AND FIBRILLIN GENOTYPE

Purpose: To screen patients with abdominal aortic aneurism for poplite al aneurysm and investigate cardiovascular and genetic risk factors as sociated with aneurysmal disease at move than one site (generalised an eurysmaI disease). Subjects, design ann setting: All patients referred to the Regional Vascular Surgical Service al Charing Cross Hospital w ith unruptured abdominal aortic aneurysm between 1989 and 1993 were sc reened for popliteal aneurysms, using ultrasonography. Main outcome me asures: Palpation of a popliteal aneurysm or ultrasonographic detectio n of popliteal dilalation, where the ratio maximum popliteal fossa dia meter/suprageniculate popliteal diameter was greater than or equal to 1.5, in relation to cardiovascular and genetic risk factors. Results: Clinical examination detected popliteal aneurysms in only 11/232 patie nts (5%), but ultrasonography demonstrated the presence of popliteal a neurysm in a further 13 patients, 24/232 in total (10%). Multivariate regression identified four independent factors associated with poplite al dilatation disease : age (p = 0.046), height (p = 0.006), systolic hypertension (p = 0.037) and triglyceride concentration (p = 0.009). G eneralised aneurysmal disease and systolic blood pressure were associa ted with polymorphic variation in the fibrillin-1 gene, but not with v ariations in the apolipoprotein B and type III collagen genes. Conclus ions: Few patients with abdominal aortic aneurysm (10%) also have popl iteal aneurysms: the risk of popliteal dilatation increases with age, height, systolic blood pressure, triglyceride concentration and fibril lin genotype. The strong interaction between fibrillin genotype and bl ood pressure may contribute to the familial tendency to aortic aneurys m.