Relation of myocardial mechanics in severe XXXX to left ventricular ejection fraction and response to aortic valve replacement.

@entity1 @entity296 @entity299 @entity717 @entity472 @entity1002
@entity1002 and increased circumferential LV strain have been demonstrated in @entity1 with severe @entity472 ( @entity472 ) and normal @entity1002 ( @entity1002 ). Biplane myocardial mechanics normalize after aortic valve replacement (AVR). This study objective was to examine LV mechanics before and soon after AVR in @entity1 with @entity472 and LV @entity299 . Paired echocardiographic studies before and soon (7    3 days) after AVR were analyzed in 64 @entity1 with severe @entity472 : 32 with normal @entity1002 (>=  50%), 16 with mild to moderate @entity1002 ( @entity1002 <36% to 50%), and 16 with severe @entity1002 ( @entity1002  <= 35%). @entity296 was assessed from 3 apical views (average of 18 segments) and circumferential function was assessed at mid-LV and apical levels (average of 6 segments per view). Strain, strain rate, and mid-LV and apical rotations were measured using 2-dimensional velocity vector imaging. Before AVR (1) longitudinal strain was low in all @entity1 and correlated with @entity1002 (   = 0.74, p <0.001), (2) mid-LV circumferential strain was supranormal in @entity1 with normal @entity1002 and low in @entity1 with low @entity1002 (   = 0.88, p <0.001), and (3) @entity717 was highest in @entity1 with mild to moderate @entity1002 . After AVR, @entity1002 increased in @entity1 with @entity1002 and myocardial mechanics partly normalized. In conclusion, compensatory mechanisms (high circumferential strain in @entity1 with preserved @entity1002 and increased @entity717 in @entity1 with mild to moderate @entity1002 ) were observed in @entity1 with severe @entity472 . Compensatory mechanics were lost in @entity1 with severe @entity1002 . AVR partly reversed these changes in @entity1 with @entity1002 .
