CMR to Evaluate Aortic Regurgitation After Transcatheter Aortic Valve Replacement
Monday, August 1, 2016
Ribeiro HB et al et al.
JACC 2016;68:577-85. Link - http://content.onlinejacc.org/article.aspx?articleID=2538677
Background Residual aortic regurgitation (AR) following transcatheter aortic valve replacement (TAVR) is associated with greater mortality; yet, determining AR severity post-TAVR using Doppler echocardiography remains challenging. Cardiovascular magnetic resonance (CMR) is purported as a more accurate means of quantifying AR; however, no data exist regarding the prognostic value of AR as assessed by CMR post-TAVR.
Objectives This study sought to evaluate the effect of AR assessed with CMR on clinical outcomes post-TAVR.
Methods We included 135 patients from 3 centers. AR was quantified using regurgitant fraction (RF) measured by phase-contrast velocity mapping CMR at a median of 40 days post-TAVR, and using Doppler echocardiography at a median of 6 days post-TAVR. Median follow-up was 26 months. Clinical outcomes included mortality and rehospitalization for heart failure.
Results Moderate-severe AR occurred in 17.1% and 12.8% of patients as measured by echocardiography and CMR, respectively. Higher RF post-TAVR was associated with increased mortality (hazard ratio: 1.18 for each 5% increase in RF [95% confidence interval: 1.08 to 1.30]; p < 0.001) and the combined endpoint of mortality and rehospitalization for heart failure (hazard ratio: 1.19 for each 5% increase in RF; 95% confidence interval: 1.15 to 1.23; p < 0.001). Prediction models yielded significant incremental predictive value; CMR performed a median of 40 days post-TAVR had a greater association with post-TAVR clinical events compared with early echocardiography (p < 0.01). RF ≥30% best predicted poorer clinical outcomes (p < 0.001 for either mortality or the combined endpoint of mortality and heart failure rehospitalization).
Conclusions Worse CMR-quantified AR was associated with increased mortality and poorer clinical outcomes following TAVR. Quantifying AR with CMR may identify patients with AR who could benefit from additional treatment measures.
COMPETENCY IN PATIENT CARE: In patients with AR after TAVR, a regurgitant fraction ≥30% as measured by CMR at a median of 40 days is associated with increased mortality and rehospitalization for heart failure.
TRANSLATIONAL OUTLOOK: Further studies are needed to define the value of CMR in guiding therapeutic interventions to improve outcomes in patients with AR following TAVR.