Imminent risk of LVEF decline in asymptomatic patients with primary mitral regurgitation

Jingyi Zheng; Shao-Wei Huang; Mustafa I Ahmed; Betty Pat; Steven G Lloyd; Oleg F Sharifov; Thomas S Denney Jr; Louis J Dell'Italia

doi:10.3389/fcvm.2024.1410859

Imminent risk of LVEF decline in asymptomatic patients with primary mitral regurgitation

Front Cardiovasc Med. 2024 Oct 14:11:1410859. doi: 10.3389/fcvm.2024.1410859. eCollection 2024.

Authors

Jingyi Zheng¹, Shao-Wei Huang¹, Mustafa I Ahmed², Betty Pat^{2

3}, Steven G Lloyd^{2

3}, Oleg F Sharifov², Thomas S Denney Jr⁴, Louis J Dell'Italia^{2

3}

Affiliations

¹ Department of Mathematics and Statistics, Auburn University, Auburn, AL, United States.
² Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, AL, United States.
³ Research & Development Service, Birmingham Veterans Affairs Health Care System, Birmingham, AL, United States.
⁴ Department of Electrical and Computer Engineering, Samuel Ginn College of Engineering, Auburn University, Auburn, AL, United States.

Abstract

Background: 2020 American College of Cardiology/American Heart Association (ACC/AHA) Guidelines state that the ideal time for mitral valve surgery in primary mitral regurgitation (PMR) is when the LV approaches but has not yet reached echocardiographic LV ejection fraction (EF) < 60% or LV end-systolic dimension (ESD) > 40 mm. However, it is difficult to know the imminent risk of crossing this threshold when the surgical outcome is less optimal.

Objective: Using machine learning and statistical models, we have shown that cardiac magnetic resonance (CMR) LV sphericity index (SI) and LV mid circumferential strain rate (SR_circ) added to LVEF and LVESD predict LVEF < 50% after mitral valve surgery. Here we test the hypothesis that these CMR features predict LVEF < 60% in asymptomatic PMR patients at 18 months.

Methods: 33 asymptomatic PMR patients with moderate to severe mitral regurgitation had CMR with tissue tagging at baseline and every 6 months for 18 months. Two types of models were employed to predict LVEF < 60% at 18 months: a model using CMR features at a single time point (e.g., baseline) and a model utilizing repeated measurements over time.

Results: CMR LVEF decreased below 60% in 13 patients over 18 months. LVEF varied over time with an inverse relation to mean arterial pressure and mean end-systolic wall stress. Random Forest models utilizing LV SI, LV mid SR_circ, LVESD, and LVEF at a single time point (baseline) had a predictive accuracy of 64%. LV SI, LV mid SR_circ, LVESD and LVEF at baseline, 6, and 12 months achieved a higher predictive accuracy of 79%, improved sensitivity from 57% to 85% than baseline alone and identified a threshold of CMR LVEF 63%-64% signaling LVEF < 60%.

Conclusion: The variability of LVEF due to blood pressure dependence may require a longitudinal study that incorporates LVEF, LVESD, SR_circ at multiple time points to identify the threshold at which LVEF is at risk for decline to less than 60%.

Keywords: LV circumferential strain rate; LVEF decline; asymptomatic primary mitral regurgitation; cardiac MRI; machine learning; predictive longitudinal modeling.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by the National Heart, Lung, and Blood Institute and Specialized Centers of Clinically Oriented Research grant [P50HL077100 to L.J.D] in cardiac dysfunction; Department of Veteran Affairs for Merit Review grant [1CX000993-01 to L.J.D]; and National Institutes of Health Grant [P01 HL051952 to L.J.D]. VHA 2021 John Blair Barnwell Award [to LJD]; No relationships to industry.