Three-Dimensional Strain Reveals Regional Myocardial Dysfunction After Mitral Annuloplasty
Background: Left ventricular (LV) dysfunction is well recognized after mitral valve repair (MVR), however, changes in regional function have not been described. We hypothesize that MVR will cause discrete changes in regional myocardial function.
Methods: A 3D transthoracic echocardiogram was performed pre- and postoperatively (MV repair, n=48 and CABG, n=50). Global 3D area, circumferential, and longitudinal strain were measured, along with segmental 3D area (AS), circumferential (CS), and longitudinal (LS) strain.
Results: After MVR, global strain decreased significantly. The largest magnitude reductions were seen in the LV anterior (AS: -41%, CS: -43%, LS: -40%, p<0.05), inferior (AS: -34%, CS: -45%, p<0.05), and apical (AS: -38%, CS: -37%, LS: -40%, p<0.01) regions. Compared to CABG, reductions in LV anterior (AS: -41% vs. -36%, p=0.035) and inferior (-34% vs. -18%, p=0.005) regional strain were greater following MVR.
Conclusions: Annuloplasty alters mitral annular mechanics and reduces LV anterior and inferior regional myocardial strain.