How to: Quantitative Analysis in a Secondary Mitral Regurgitation
Using Quantitative PISA and Stroke Volume Methods
May 10, 2022
Pages 1 – 7
- Quantification of mitral regurgitation
- PISA method
- Stroke volume method
- Vena contracta method
- Color Doppler
- Pulsed Doppler
It is very important to both learn the basics of the quantification of mitral regurgitation and practice the necessary learning curve to acquire personal accuracy and reproducibility. According to the current Guidelines, surgery or intervention is recommended for severe regurgitation in symptomatic patients, selected asymptomatic patients, and a few instances of moderate regurgitation. Echocardiography is the first-line diagnostic tool for valvular heart disease and is often the only one being used before intervention. Thus the information provided by the sonographer/cardiologist is of utmost importance since the “Heart team” decisions are often primarily based on this information.
Given that the decision to perform surgery/intervention is primarily based on the grade of regurgitation (severe / not severe), the main goal of the operator performing the exam is to define accurately the regurgitation grade. The quantification of the grade of mitral regurgitation is a difficult task that requires:
1. Familiarity with the available tools (M-mode, 2D, pulsed, continuous wave, color Doppler echocardiography)
2. Knowledge of the diagnostic methods (Qualitative, Quantitative)
3. Learning curve + Experience
It is never enough to stress the importance of an adequate learning curve to gain confidence and personal accuracy in identifying the grade of valvular regurgitation. Even a very experienced operator who has never performed a stroke volume determination will have initially a low accuracy. Maybe this is the line of reasoning behind the unfortunate recent ESC-EACVI Recommendations that downgrade the stroke volume method to quantify valvular regurgitation to a second-line method that is “time-consuming and is associated with several drawbacks” (of note, references mentioned in support are nonspecific). Although the main limitation of the stroke volume method is that it is limited to single valve lesions, it certainly takes less time than the recommended 3D measurement of the vena contracta.
I personally recommend the stroke volume method as the echocardiographic gold standard method to quantify mitral regurgitation before an intervention. Of note, the methodology recommended by the Guidelines includes the assumption of a circular mitral annulus geometry, which inherently leads to an overestimation of the mitral stroke volume and consequently of the regurgitant volume (compare by yourself calculations with a circular versus an oval mitral annulus geometry here)
(tt2942). This is a 68 year-old male patient (BSA= 1.78 m2) with dilative ischemic heart disease. Heart rate= 85 bpm. The echocardiographic examination shows:
- End diastolic volume index= 133 ml/m2 (moderate dilatation)
- LV End-diastolic / end-systolic diameters= 80 / 68 mm
- LV ejection fraction= 26 % (severe reduction)
- Stroke volume index= 35 ml/m2 (low normal)
- Left atrial volume index= 56 ml/m2 (moderate to severe dilatation)
- Elevated LV filling pressures (E/e’= 26)
- Mitral E wave peak velocity= 115 cm/s
- Pulmonary venous flow= diastolic dominant
- Normal estimated pulmonary systolic pressure
- Normal estimated right atrial pressure
The required task is to quantify the associated mitral regurgitation. The patient is in NYHA II, without angina and following Guidelines directed medical therapy.
The 2D exam (Figures 1-2) showsa severe dilative ischemic heart disease with severe diffuse hypo-akinesis, minimal fibrotic thickening and mild systolic tenting of the leaflets; moderate to severe dilatation of the left atrium with impairment of the reservoir function; normal dimensions and systolic function of the right ventricle.
- Evaluation of mitral valve regurgitation: summary of Qualitative and Quantitative parameters
- See also Doppler echocardiographic Criteria to Grade mitral regurgitation (in this website)