Page 108 - Advanced echocardiography in characterization and management of patients with secondary mitral regurgitation

Chapter five. MV geometry: The COAPT Trial
Death or HFH at 24 months occurred in 44.8% of patients randomized to MitraClip plus GDMT and in 66.1% of the patients randomized to GDMT alone (P<0.0001). MitraClip treatment was an independent predictor of a 48% reduction in the primary composite endpoint (P<0.0001; Table 4). By formal interaction testing, increasing anteroposterior mitral annular diameter was associated with a similar risk of the composite primary endpoint for both treatment arms (Central Illustration, Panel A). Similarly, no significant interactions between atrial fibrillation, NYHA class or BNP plasma levels and treatment arm were present for the primary composite outcome.
Impact of mitral valve geometry on all-cause death and heart failure hospitalization as separate outcomes
A larger mitral EROA was the only echocardiographic variable independently associated with an increased risk of all-cause mortality within 2 years (Supplemental Appendix Table 2). Other independent correlates of increasing mortality were creatinine clearance, 6-minute walk distance, BNP levels and EROA. MitraClip treatment was an independent predictor of a 38% reduction in 2-year mortality (P=0.003).There were no significant interactions noted between these variables and treatment arm on 24-month all-cause mortality (Central Illustration, Panel B).
Among the echocardiographic and mitral valve geometric variables, only the anteroposterior mitral annular diameter was independently associated with 2-year HFH (Supplemental Appendix Table 3). Other independent correlates of increasing mortality were history of atrial fibrillation or flutter, NYHA class, and BNP levels. MitraClip treatment was an independent predictor of a 57% reduction in 2-year HFH (P<0.001). There were no significant interactions noted between these variables and treatment arm on 24-month HFH (Central Illustration, Panel C).
Discussion
In the present sub-study from the COAPT trial, among HF patients with severe secondary MR, an increasing anteroposterior mitral annular diameter was associated with the 2-year composite endpoint of all-cause mortality or heart failure hospitalization, an association that was driven by an increasing risk of HFH more so than mortality. In contrast, baseline EROA was independently associated with the 2-year rate of all-cause mortality but not HFH. Treatment with MitraClip compared with GDMT alone reduced the relative 2-year risks of all-cause death, HFH and the composite of death or HFH consistently in all subgroups, including larger vs. smaller anteroposterior mitral annular
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