Background: Quantification of myocardial changes in severe aortic stenosis (AS) is prognostically important. The potential for comprehensive myocardial assessment pre-transcatheter aortic valve replacement (TAVR) by computed tomography angiography (CTA) is unknown.
Objectives: This study sought to evaluate whether quantification of left ventricular (LV) extracellular volume-a marker of myocardial fibrosis-and global longitudinal strain-a marker of myocardial deformation-at baseline CTA associate with post-TAVR outcomes.
Methods: Consecutive patients with symptomatic severe AS between January 2021 and June 2022 who underwent pre-TAVR CTA were included. Computed tomography extracellular volume (CT-ECV) was derived from septum tracing after generating the 3-dimensional CT-ECV map. Computed tomography global longitudinal strain (CT-GLS) used semi-automated feature tracking analysis. The clinical endpoint was the composite outcome of all-cause mortality and heart failure hospitalization.
Results: Among the 300 patients (80.0 ± 9.4 years of age, 45% female, median Society of Thoracic Surgeons Predicted Risk of Mortality score 2.80%), the left ventricular ejection fraction (LVEF) was 58% ± 12%, the median CT-ECV was 28.5% (IQR: 26.2%-32.1%), and the median CT-GLS was -20.1% (IQR: -23.8% to -16.3%). Over a median follow-up of 16 months (IQR: 12-22 months), 38 deaths and 70 composite outcomes occurred. Multivariable Cox proportional hazards model, accounting for clinical and echocardiographic variables, demonstrated that CT-ECV (HR: 1.09 [95% CI: 1.02-1.16]; P = 0.008) and CT-GLS (HR: 1.07 [95% CI: 1.01-1.13]; P = 0.017) associated with the composite outcome. In combination, elevated CT-ECV and CT-GLS (above median for each) showed a stronger association with the outcome (HR: 7.14 [95% CI: 2.63-19.36]; P < 0.001).
Conclusions: Comprehensive myocardial quantification of CT-ECV and CT-GLS associated with post-TAVR outcomes in a contemporary low-risk cohort with mostly preserved LVEF. Whether these imaging biomarkers can be potentially used for the decision making including timing of AS intervention and post-TAVR follow-up will require integration into future clinical trials.
Competing Interests: Funding Support and Author Disclosures This research was supported unrestricted research grant by Ziosoft. Dr Treibel is a shareholder of Mycardium AI Ltd. Dr Enriquez-Sarano has received consulting fees from CryoLife, Edwards Lifesciences, Highlife, and ChemImage. Dr Sorajja has received consulting fees from 4C Medical, Anteris, Abbott Structural, Boston Scientific, Edwards Lifesciences, Evolution Medical, Foldax, GLG, Medtronic, Phillips, Siemens, Shifamed, W.L. Gore, vDyne, and xDot; has served on the REPAIR MR Steering Committee, EXPAND Steering Committee, W.L. Gore Pipeline Executive Committee, SUMMIT Steering Committee, TRILUMINATE Steering Committee, TRILUMINATE Eligibility Committee for Anatomy, G4 Adverse Leaflet Events Committee, and Neovasc Executive Steering Committee; and has served as a national or global principal investigator for the TRILUMINATE Pivotal US Trial, SUMMIT MAC Pivotal Trial, EXPAND EFS and Pivotal US Trial, HighLife (USA) EFS, VDyne EFS, SOAR EFS, and AMEND EFS. Dr Bapat has received consulting fees from Abbott Structural, Boston Scientific, Edwards Lifesciences, and Medtronic. Dr Leipsic has received consulting fees from Circle CVI; personal CT core lab fees from MVRX; and institutional core lab fees from Boston Scientific, Abbott, Medtronic, Edwards Lifesciences, and Pi-Cardia. Dr Cavalcante has received consulting fees from 4C Medical, Abbott Structural, Anteris, AriaCV, Boston Scientific, Edwards Lifesciences, Medtronic, VDyne, W.L. Gore, and Xylocor; and research grant support from the Abbott Northwestern Hospital Foundation. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
(Copyright © 2024 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)