Abstract 16905: Evaluation of Immediate Procedural Outcome After MitraClip Using Automated Quantitaive Real-time Volume Color Flow Doppler Transesophageal Echocardiography

Abstract

Background: Current echocardiographic evaluation of residual MR after Mitra-Clip is based on a semi-quantitative scale (trace to 4+). We evaluated a previously validated quantitative approach using automated real-time volume color flow Doppler (3D-RTVCFD). Methods: 30 patients (age 82 ± 5) underwent Mitra-Clip implantation guided by 3D-RTVCFD TEE (Siemens SC2000, CA). In 10 patients, data to automatically quantify 3-D regurgitant volume (RV, ml) and fraction (RF, %) and anatomic regurgitant orifice area (AROA) was available (Figure, upper panel). All patients had conventional 2-D Echo data for assessment of MR severity using the standard integrated approach. Results: MR was severe (4+) in 8, and moderately severe (3+) in 2 patients at baseline. MR post Mitra-Clip was mild or trace in 6 (≤1+, Group 1), and moderate in 4 (Group 2) patients. At baseline, the (mean±SD) 3-D RV/RF was 54.5±19.9 ml/60.6±10.2% and the AROA was 0.6±0.2 cm2 for the whole group. Post Mitra-Clip, the 3-D RV/RF was 23.6±10.3 ml/37.0±13.9% (p<0.01/p<0.001 vs. baseline) and the AROA was 0.3±0.1 cm2 (p<0.05). Both Group 1 and Group 2 had similar baseline RF, and both demonstrated a 39% and 38% decrease in RF post Mitra-clip, respectively (Figure, bottom graph). The decrease in AROA in both groups post Mitra-Clip was also significant (~53% in Group 1 and ~59% in Group 2). Thus, despite “moderate” residual MR using the semi-quantitative scale in Group 2, there was significant decreases in both RF and AROA. Conversely, in Group 1 some of the residual MR assessed as “mild” indeed had 3-D RF and AROA in the moderate range, post Mitra-clip. Conclusion: Automated quantitative 3-D real-time volume color flow Doppler TEE offers a quantitative assessment of residual MR post Mitra-clip immediately after the procedure. This may refine decision-making with regard to number of clips. Both accuracy of 3D RTVCFD TEE to quantify MR and it’s predictive value for mid- to long term procedural success need further studies.