4D flow MRI left atrial kinetic energy in hypertrophic cardiomyopathy is associated with mitral regurgitation and left ventricular outflow tract obstruction.

To noninvasively assess left atrial (LA) kinetic energy (KE) in hypertrophic cardiomyopathy (HCM) patients using 4D flow MRI and evaluate coupling associations with mitral regurgitation (MR) and left ventricular outflow tract (LVOT) obstruction. Twenty-nine retrospectively identified patients with HCM underwent 4D flow MRI. MRI-estimated peak LVOT pressure gradient (∆P) was used to classify patients into non-obstructive and obstructive HCM.