Abstract
Basal interventricular septum (IVS) hypertrophy (BSH) is characterized by a reduced aortoseptal angle and thickened basal IVS. The BSH shape suggests compression by the longitudinally elongated ascending aorta (pseudohypertrophy), further suggesting the possibility of surgical aortic wall shortening to improve the BSH. We report the case of a 77-year-old woman with an asymptomatic dissecting thoracic ascending aortic aneurysm and clear BSH. Surgical aortic root replacement with longitudinal wall shortening clearly improved the BSH, demonstrating the beneficial effects on BSH of surgical aortic wall shortening.