Aortic root geometry in bicuspid aortic insufficiency versus stenosis: implications for valve repair

OBJECTIVES: The contribution of aortic annular and root disease in bicuspid aortic valve (BAV) insufficiency remains unclear. We compared aortic root geometry between BAV stenosis and aortic insufficiency (AI), before and after repair. METHODS: Patients presenting for surgery for BAV insufficiency (n = 58) were compared with patients with BAV stenosis (n = 58). Clinical and transoesophageal echocardiographic data were collected, including end-diastolic diameters of the ventriculo-aortic junction (VAJ), aortic root, sinotubular junction (STJ) and ascending aorta (AA). RESULTS: AI patients were younger and more likely to be male compared with aortic stenosis (AS) patients. VAJ, aortic root and STJ diameters were significantly larger in AI compared with AS patients (30 +/- 0.5 vs 25 +/- 0.4 mm, P < 0.001; 41 +/- 0.8 vs 34 +/- 0.6 mm, P < 0.001; 36 +/- 0.9 vs 30 +/- 0.6 mm, P < 0.001, respectively). Following multivariable adjustment for age, sex, body surface area and ascending aortic diameter, these diameters remained larger in AI patients with a mean difference of 3, 6 and 4 mm, respectively (all P < 0.001). Mean AA diameter in the AI group was similar to the AS group (37 +/- 1.0 vs 34 +/- 0.8 mm, P = 0.06). Forty (69%) AI patients had BAV repair with a mean reduction in VAJ and STJ diameters of 5 and 9 mm compared with prerepair (P < 0.0001). CONCLUSIONS: Despite the absence of aortic aneurysms, aortic annulus and root dimensions are significantly larger in patients with BAV insufficiency compared with stenosis. Alterations in aortic root geometry contribute to the pathophysiology of BAV insufficiency and require correction for a successful repair.