True morphology of mitral regurgitant flow assessed by three-dimensional transesophageal echocardiography

Echocardiography. 2017 Jan;34(1):87-93. doi: 10.1111/echo.13395. Epub 2016 Oct 4.

Abstract

Introduction: Quantification of mitral regurgitation (MR) by two-dimensional (2D) transthoracic echocardiography (TTE) is based on the analysis of the proximal flow convergence (PFC) and the "vena contracta" (VC). This method assumes geometries and can be misleading. In contrast, three-dimensional (3D) echocardiography directly measures flow volumes and does not assume geometries, which allows for more accurate MR evaluation.

Aims: To report the 3D transesophageal echocardiography (3DTEE) feasibility for MR quantification and evaluate its concordance with 2D echo.

Methods: Twenty-seven consecutive patients undergoing 2D and 3DTEE for presurgical MR evaluation were studied prospectively. MR quantification was performed by classical 2D methods based on PFC. Diameters of the VC in orthogonal planes by 3DTEE were estimated, establishing the VC sphericity index as well as VC area (VCA) by direct planimetry. In case of multiple jets, we calculated the sum of the VCA.

Results: MR assessment by 3DTEE was feasible. An adequate concordance between VC measurements by 2D methods (TTE and TEE) was observed; however, there was a poor correlation when compared with 3DTEE. The sphericity index of the VC was: 2.08 (±0. 72), reflecting a noncircular VC.

Conclusions: 3DTEE is a feasible method for the assessment of the MR true morphology, allowing a better quantification of MR without assuming any geometry. This method revealed the presence of multiple jets, potentially improving MR evaluation and leading to changes in medical decision when compared to 2D echo assessment.

Keywords: mitral regurgitation; proximal flow convergence; three-dimensional echocardiography; vena contracta.

MeSH terms

  • Blood Flow Velocity / physiology*
  • Echocardiography, Doppler, Color / methods
  • Echocardiography, Three-Dimensional / methods*
  • Echocardiography, Transesophageal / methods*
  • Feasibility Studies
  • Female
  • Humans
  • Male
  • Middle Aged
  • Mitral Valve / diagnostic imaging*
  • Mitral Valve / physiopathology
  • Mitral Valve Insufficiency / diagnosis*
  • Mitral Valve Insufficiency / physiopathology
  • Reproducibility of Results
  • Severity of Illness Index