Normal pulmonary valve sinuses in a 58-year-old woman. RVOT (a,
b) and short-axis (c, d) bright-blood cine SSFP
MR images show normal pulmonary valve sinuses at end diastole (a,
c) and end systole (b, d). On the short-axis
images, the pulmonary valve sinus (arrows in c, d) can give
the appearance of dyskinetic systolic wall motion. To avoid
misdiagnosis, it is important to identify the level of the pulmonary
valve annulus (dotted line in a, b). Normal outpouching of
the sinuses (arrow in a, b) occurs above the level of the
annulus, whereas wall motion abnormalities in ARVC occur below this
level.