Background: Altered hemodynamics is recognized as a key contributor to the development and progression of cardiovascular diseases. Previous 4D flow MRI studies on the ascending aorta (AAo) hemodynamics have shown that supra-physiological helical blood flow patterns are implicated in the pathophysiology of aortopathy. However, most of these in vivo studies either adopt a qualitative approach or perform a quantitative characterization of helical flow limited to specific analysis planes or single cardiac phases. A very recent, more comprehensive 4D flow MRI quantitative study has shown that aortic valve phenotype (tricuspid vs. bicuspid) plays a crucial role in shaping helicity in the AAo.