From the Guidelines
To assess mitral regurgitation with TTE, follow a stepwise approach that includes evaluating mitral valve morphology and function, assessing MR severity using multiple parameters, and evaluating left ventricular and left atrial size and function, as recommended by the most recent guidelines 1. The steps to assess mitral regurgitation with TTE are as follows:
- Determine the etiology of MR by evaluating mitral valve morphology and function, distinguishing between primary (structural valve abnormalities) and secondary (ventricular dysfunction) causes.
- Assess MR severity using multiple parameters including color Doppler jet area, vena contracta width, effective regurgitant orifice area, regurgitant volume, and regurgitant fraction.
- Evaluate left ventricular size and function, measuring end-diastolic and end-systolic dimensions, ejection fraction, and wall motion abnormalities.
- Assess left atrial size, as enlargement suggests chronic MR.
- Measure pulmonary artery pressure using tricuspid regurgitation velocity, as elevated pressures may indicate advanced MR.
- Evaluate right ventricular size and function, as right ventricular dysfunction may develop in severe MR. It is essential to use a comprehensive approach, as each individual measurement has limitations, and integrating these findings helps determine MR severity, mechanism, and hemodynamic consequences, which guide clinical management decisions regarding timing of intervention versus continued surveillance 1. The use of TTE as the first-line imaging modality in valvular regurgitation is recommended, and TOE is advocated when TTE is of non-diagnostic value or when further diagnostic refinement is required 1. In addition, three-dimensional echocardiography can provide additional information in patients with complex valve lesions, and allows more accurate quantitation of haemodynamic consequences of the regurgitation on cardiac chambers 1. The most recent guidelines recommend using a combination of parameters to assess MR severity, including color Doppler jet area, vena contracta width, effective regurgitant orifice area, regurgitant volume, and regurgitant fraction 1. It is also important to consider the clinical context and the potential for changes in MR severity with maneuvers that decrease LV preload or afterload, as well as the potential for improvement with control of blood pressure in patients with hypertensive urgency/emergency 1.
From the Research
Assessment of Mitral Regurgitation with TTE
The assessment of mitral regurgitation using Transthoracic Echocardiography (TTE) involves several steps, including:
- Functional analysis of mitral regurgitation using standardized imaging planes 2
- Quantification of mitral regurgitation severity using qualitative and semiquantitative techniques 3
- Evaluation of mitral valve geometry and pathology using three-dimensional TTE 4
Steps to Assess Mitral Regurgitation
The steps to assess mitral regurgitation with TTE are:
- Use of harmonic imaging to evaluate the mitral valve and left ventricle 2
- Assessment of mitral regurgitation severity using color Doppler and spectral Doppler techniques 3
- Measurement of mitral effective regurgitant orifice area (EROA) and regurgitant volume (Rvol) using 2D and 3D TTE 5
- Evaluation of mitral valve prolapse and regurgitation using live/real-time three-dimensional TTE 4
Importance of TTE in Mitral Regurgitation Assessment
TTE is the main investigation and first approach used to diagnose mitral regurgitation, assess its severity, and describe the underlying mechanism 6. It can predict accurately valve repairability and has a strong influence on postoperative outcome 2. However, TEE, especially with 3D echocardiography, may be useful for clarifying complicated valvular anatomy and assessing the surgical result 6.