In acute severe aortic regurgitation, an inversion of pressure gradient from the left ventricle to the left atrium causes the classical sign of end-diastolic mitral regurgitation. Here we present a case of mid-diastolic mitral regurgitation in a 51-year-old man with severe aortic regurgitation secondary to infective endocarditis. (Level of Difficulty: Beginner.) Graphical abstract In acute severe aortic regurgitation, an inversion of pressure gradient from the left ventricle to the left atrium causes the classical sign of end…