Abstract 16659: Neo LVOT Prediction With the Innovalve TMVR System - CT Preliminary Results

Abstract

Introduction: The Innovalve TMVR is a novel self-expandable trans-catheter mitral valve prosthesis, delivered trans-septally using femoral venous access. It is deployed in an intra-valvular posterior position after sub-valvular anchoring by rotation of 6 circumferential arms. LV outflow tract (LVOT) compromise is of great concern in TMVR. A predicted Neo LVOT area of 170 mm 2 is the currently accepted cut-off for LVOT obstruction. Hypothesis: CT can accurately predict the Neo LVOT area prior to Innovalve TMVR procedure. Methods: CT was performed as a screening tool to evaluate the Neo LVOT area prior to Innovalve TMVR procedure. CT protocol: Retrospectively ECG gated with full cardiac cycle coverage. CT was performed before and after the procedure. Predicted Neo LVOT (pNLVOT) was calculated using a dedicated simulation valve prior to TMVR, actual Neo LVOT (aNLVOT) was calculated with the inserted valve in place following TMVR. The native LVOT (nLVOT) area, the predicted % LVOT reduction (nLVOT area-pNLVOT area /nLVOT area), the actual % LVOT reduction (nLVOT area-aNLVOT area /nLVOT area) and the difference between them (pNLVOT%-aNLVOT%) were calculated. Results: One hundred patients were screened for Innovalve TMVR procedure based on Neo LVOT criteria. pNLVOT≥ 170 mm 2 was found in 11 patients (11%), (7 males) average age 68±10 years, these patients underwent Innovalve TMVR procedure. The median calculated LVOT was 647.8+/-260 mm 2 (range 373-1312), the median pNLVOT reduction was 16% ±15 (range 3-53), the median aNLVOT reduction was 5%±14 (range -5-40) and the median difference between the pNLVOT and aNLVOT was 8±12 (range -4-31). In 8/11 patients (73%), the aNLVOT was larger than the pNLVOT (range difference 1 to 31%). In 3/11 patients (27%), the aNLVOT was smaller than the pNLVOT (range difference -1 to -4%). Conclusions: Underestimation of neoLVOT reduction, was uncommon and documented only minor and clinically insignificant difference between the pNLVOT and aNLVOT. As overestimation of NLVOT reduction allows a margin of safety for MTVR, we conclude that CT can serve as reliable NLVOT screening tool.