0179: Assessment of paravalvular aortic regurgitation after transcatheter aortic valve implantation using cardiac magnetic resonance imaging: a comparative study with echocardiography and angiography

Abstract

Assessment of paravalvular aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI) using Edwards SAPIEN XT valve remains challenging using transthoracic echocardiography (TTE) or angiography. Cardiac magnetic resonance imaging (c-MRI) has a low intraobserver and interobserver variability in the assessment of regurgitant volumes and might be more reliable to assess AR post-TAVI. We therefore aimed to evaluate the value of c-MRI to assess paravalvular AR after TAVI. Between February 2012 and March 2013, 132 consecutive patients underwent successful TAVI using exclusively Edwards SAPIEN XT prosthesis. AR was evaluated by c-MRI, TTE and angiography in 45 patients (27 women, mean age 84.1±7.1 years). Angiography was performed immediately after TAVI whereas TTE and c-MRI were performed one month after implantation. At baseline c-MRI, the mean aortic regurgitant fraction (ARF) was 21.3±12.5%. A significant AR (> grade II) was present in 24 (56%) patients using c-MRI (30< ARF>50 Y%) whereas it was only observed in 18 (40%) and 12 (27%) patients using TTE and angiography, respectively. Interestingly, there was a poor correlation between c-MRI and TTE (r=0.16, p=0.28) and between c-MRI and angiography (r=0.30, p=0.06). In contrast, there was a good correlation between TTE and angiography (r=0.6, p<0.001). TTE underestimated AR by one degree in 9 patients, and by two degrees in 6 patients as compared to c-MRI. The results of our study suggest that TTE and angiography may underestimate the severity of AR after TAVI as compared to c-MRI. Furthermore, there is a poor correlation between c-MRI and TTE or angiography. Further studies are mandatory to confirm our results in a larger population.