Contemporary Review on Multi-Modality Imaging Evaluation and Management of Functional Mitral Regurgitation

Abstract

Functional mitral regurgitation (FMR) is a prevalent valvular disorder driven by adverse remodeling of the left ventricle and/or left atrium. This review synthesizes the contemporary evidence on multimodality imaging and its role in mechanism-specific evaluation and management of FMR, with particular emphasis on distinguishing ventricular FMR (VFMR) from atrial FMR (AFMR). FMR is mechanistically heterogeneous, requiring precise phenotyping to guide therapy. A mechanism-based framework differentiating VFMR, driven by left ventricular dilation and leaflet tethering, from AFMR, driven by left atrial and annular enlargement with preserved ventricular function, is central to contemporary management. Echocardiography remains the cornerstone for real-time assessment of MR severity, hemodynamics, and valve-ventricle interactions. Cardiac magnetic resonance (CMR) provides the gold standard for volumetric quantification and myocardial tissue characterization, enabling improved risk stratification by assessing ventricular remodeling and fibrosis. Computed tomography (CT) offers high-resolution anatomic phenotyping and is essential for procedural planning, particularly for transcatheter edge-to-edge repair (TEER) and transcatheter mitral valve replacement (TMVR). Integration of multimodality imaging supports individualized selection between guideline-directed medical therapy alone, TEER, surgical intervention, or TMVR, based on the dominant mechanism and myocardial substrate. The discordant outcomes of landmark trials such as MITRA-FR and COAPT have underscored the importance of precision in patient selection, highlighting the controversial but clinically relevant proportionate/disproportionate FMR framework and the extent of myocardial fibrosis as key modifiers of treatment response. Emerging advances in advanced imaging and artificial intelligence hold promise for automated phenotyping, improved reproducibility, and earlier identification of patients most likely to benefit from intervention, ultimately enabling a more personalized, mechanism-driven approach to improving outcomes in FMR.

Keywords

Functional mitral regurgitation / Mitral valve / Echocardiography / Cardiac magnetic resonance / Computed tomography / Transcatheter interventions / Mitral valve surgery

Statement of the Use of Generative AI and AI-Assisted Technologies in the Writing Process

The authors used Google Gemini and ChatGPT 5.2 to generate ideas for visualizing and presenting the illustrations described in the paper. Grammarly was used to improve grammar and edit paragraphs in the manuscript. After using these tools, the authors reviewed and made necessary edits to the content, taking full responsibility for the final article published.

Author Contributions

Conceptualization, T.K.M.W. and S.-W.L.; Methodology (literature search strategy), S.-W.L.; Validation (critical review of arguments), J.E.R., Y.-F.T., C.T. and T.K.M.W.; Investigation (literature collection), S.-W.L. and J.E.R.; Resources, T.K.M.W.; Writing—Original Draft Preparation, S.-W.L.; Writing—Review & Editing, S.-W.L., J.E.R., Y.-F.T., C.T. and T.K.M.W.; Visualization, S.-W.L.; Supervision, T.K.M.W.; Project Administration, T.K.M.W.; Funding Acquisition, T.K.M.W.

Ethics Statement

Not applicable. This is a review article that synthesizes and summarizes previously published literature and does not involve any new studies with human participants or animals performed by any of the authors.

Informed Consent Statement

Not applicable. This review article does not contain any studies with human participants performed by any of the authors.

Data Availability Statement

No new data were created or analyzed in this study. Data sharing is not applicable to this article. All information discussed in this review is based on previously published studies, which are cited in the reference list.

Funding

This research received no external funding.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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