The flow-gradient pattern was determined at baseline transthoracic echocardiography and classified as follows: (1) HG; (2) CLF-LG; (3) paradoxical low-flow-LG; and (4) normal-flow-LG. 
transthoracic echocardiography
A total of 3511 patients from the PARTNER 2 Cohort A randomized trial (n=1910) and SAPIEN 3 registry (n=1601) were included. 
SAPIEN 3 registry