D-38 | 2D or not 2D: Cardiac CTA Prediction of LVOT Obstruction Following TMVR

There is no recognized standard methodology to assess neo-LVOT area predict the morbid complication of LVOT obstruction after trans-catheter mitral valve replacement (TMVR). The objective this project investigate and compare different approaches Neo-LVOT area. Thirty two patients who underwent TMVR using a heart (THV) into failed surgical MVR (SMVR) in our facility between August 2016 May 2022 were retrospectively enrolled. CT scans for planning analyzed 3Mensio software mid-systole. A THV was implanted virtually at 2 possible positions: 1) atrial alignment SMVR, 2) ventricular SMVR. Two centerline courses used study: Straight dividing equally following curve interventricular septum With perpendicular axis centerline, predicted created measured each virtual position, 2D plane or directly on 3D volume rendering. That resulted 8 measurements; 3) Curved 4) position – with measurement. Neo area/LVOT ratios calculated. Mean age 78 ± years, 47 % female. Median STS score 8.7 Both planar measurements its corresponding direct method correlated strongly other regardless course (r≥0.94 P value <0.001 all). Direct underestimated (p<0.05). modest significant correlation area, LVOT/LVOT ratio, respectively, systolic mean gradient method, (r=0.38 0.54, p<0.05 Out all performed, only had r >0.50 MG, measures did not perform better than 2D. can be many ways. measurement correlate best gradient.