Assessing the Hemodynamic Impact of Anterior Leaflet Laceration in Transcatheter Mitral Valve Replacement: An in silico Study

• Type of Material: Article
• Authors: Keshav Kohli, Georgia Institute of Technology; Zhenglun A Wei, Georgia Institute of Technology; Vahid Sadri, Georgia Institute of Technology; Andrew W Siefert, Georgia Institute of Technology; Philipp Blanke, University of British Columbia; Emily Perdoncin, Emory University Hospital; Adam Greenbaum, Emory University; Jaffar M Khan, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda; Robert Lederman, Emory University; Vasilis Babaliaros, Emory University; Ajit Yoganathan, Emory University; John Oshinski, Emory University
• Language: English
• Date: 2022-06-09
• Publisher: FRONTIERS MEDIA SA
• Publication Version: Final Published Version
• Copyright Statement: © 2022 Kohli, Wei, Sadri, Siefert, Blanke, Perdoncin, Greenbaum, Khan, Lederman, Babaliaros, Yoganathan and Oshinski.
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.3389/fcvm.2022.869259
• Title of Journal or Parent Work: FRONTIERS IN CARDIOVASCULAR MEDICINE
• Volume: 9
• Start Page: 869259
• End Page: 869259
• Grant/Funding Information: This study was supported by American Heart Association Pre-doctoral Fellowship 20PRE35200392 (Kohli) and National Institutes of Health (NIH) grant R01EB027774 (Oshinski).
• Keywords: Cardiovascular System & Cardiology; Science & Technology; PREVENT; LAMPOON; left ventricular outflow tract obstruction; OUTFLOW TRACT OBSTRUCTION; computational fluid dynamics (CFD); Cardiac & Cardiovascular Systems; neo-LVOT; transcatheter mitral valve replacement (TMVR); Life Sciences & Biomedicine; personalized computational modeling; computed tomography (CT)
• Research Categories: Health Sciences, Radiology; Engineering, Biomedical

Abstract

Background: A clinical study comparing the hemodynamic outcomes of transcatheter mitral valve replacement (TMVR) with vs. without Laceration of the Anterior Mitral leaflet to Prevent Outflow Obstruction (LAMPOON) has never been designed nor conducted. Aims: To quantify the hemodynamic impact of LAMPOON in TMVR using patient-specific computational (in silico) models. Materials: Eight subjects from the LAMPOON investigational device exemption trial were included who had acceptable computed tomography (CT) data for analysis. All subjects were anticipated to be at prohibitive risk of left ventricular outflow tract (LVOT) obstruction from TMVR, and underwent successful LAMPOON immediately followed by TMVR. Using post-procedure CT scans, two 3D anatomical models were created for each subject: (1) TMVR with LAMPOON (performed procedure), and (2) TMVR without LAMPOON (virtual control). A validated computational fluid dynamics (CFD) paradigm was then used to simulate the hemodynamic outcomes for each condition. Results: LAMPOON exposed on average 2 ± 0.6 transcatheter valve cells (70 ± 20 mm2 total increase in outflow area) which provided an additional pathway for flow into the LVOT. As compared to TMVR without LAMPOON, TMVR with LAMPOON resulted in lower peak LVOT velocity, lower peak LVOT gradient, and higher peak LVOT effective orifice area by 0.4 ± 0.3 m/s (14 ± 7% improvement, p = 0.006), 7.6 ± 10.9 mmHg (31 ± 17% improvement, p = 0.01), and 0.2 ± 0.1 cm2 (17 ± 9% improvement, p = 0.002), respectively. Conclusion: This was the first study to permit a quantitative, patient-specific comparison of LVOT hemodynamics following TMVR with and without LAMPOON. The LAMPOON procedure achieved a critical increment in outflow area which was effective for improving LVOT hemodynamics, particularly for subjects with a small neo-left ventricular outflow tract (neo-LVOT).