Mitral Valve Coaptation Reserve Index: A Model to Localize Individual Resistance to Mitral Regurgitation Caused by Annular Dilation

Jayant S Jainandunsing; Dario Massari; Jaap Jan Vos; Inez J Wijdh-den Hamer; Ad Fm van den Heuvel; Massimo A Mariani; Feroze Mahmood; Wobbe Bouma; Thomas W L Scheeren

doi:10.1053/j.jvca.2022.11.009

Mitral Valve Coaptation Reserve Index: A Model to Localize Individual Resistance to Mitral Regurgitation Caused by Annular Dilation

J Cardiothorac Vasc Anesth. 2023 May;37(5):690-697. doi: 10.1053/j.jvca.2022.11.009. Epub 2022 Nov 13.

Authors

Jayant S Jainandunsing¹, Dario Massari², Jaap Jan Vos², Inez J Wijdh-den Hamer³, Ad Fm van den Heuvel⁴, Massimo A Mariani³, Feroze Mahmood⁵, Wobbe Bouma³, Thomas W L Scheeren²

Affiliations

¹ Department of Anesthesiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands. Electronic address: jsjainandunsing@gmail.com.
² Department of Anesthesiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
³ Department of Cardiothoracic Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
⁴ Department of Cardiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
⁵ Department of Anesthesiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA.

PMID: 36509635
DOI: 10.1053/j.jvca.2022.11.009

Abstract

Objectives: The objective of this study was to develop a mathematical model for mitral annular dilatation simulation and determine its effects on the individualized mitral valve (MV) coaptation reserve index (CRI).

Design: A retrospective analysis of intraoperative transesophageal 3-dimensionalechocardiographic MV datasets was performed. A mathematical model was created to assess the mitral CRI for each leaflet segment (A1-P1, A2-P2, A3-P3). Mitral CRI was defined as the ratio between the coaptation reserve (measured coaptation length along the closure line) and an individualized correction factor. Indexing was chosen to correct for MV sphericity and area of largest valve opening. Mathematical models were created to simulate progressive mitral annular dilatation and to predict the effect on the individual mitral CRI.

Setting: At a single-center academic hospital.

Participants: Twenty-five patients with normally functioning MVs undergoing cardiac surgery.

Interventions: None.

Measurements and main results: Direct measurement of leaflet coaptation along the closure line showed the lowest amount of coaptation (reserve) near the commissures (A1-P1 0.21 ± 0.05 cm and A3-P3 0.22 ± 0.06 cm), and the highest amount of coaptation (reserve) at region A2 to P2 0.25 ± 0.06 cm. After indexing, the A2-to-P2 region was the area with the lowest CRI in the majority of patients, and also the area with the least resistance to mitral regurgitation (MR) occurrence after simulation of progressive annular dilation.

Conclusions: Quantification and indexing of mitral coaptation reserve along the closure line are feasible. Indexing and mathematical simulation of progressive annular dilatation consistently showed that indexed coaptation reserve was lowest in the A2-to-P2 region. These results may explain why this area is prone to lose coaptation and is often affected in MR.

Keywords: coaptation; echocardiography; mitral regurgitation; mitral valve; mitral valve coaptation reserve index.

MeSH terms

Computer Simulation
Dilatation
Echocardiography, Three-Dimensional* / methods
Humans
Mitral Valve / diagnostic imaging
Mitral Valve / surgery
Mitral Valve Insufficiency* / diagnostic imaging
Mitral Valve Insufficiency* / etiology
Mitral Valve Insufficiency* / surgery
Retrospective Studies