We recently received a question from one of our readers regarding grading MR severity with echo. The question was, “Are any labs still using stage I-IV for grading mitral regurgitation? I still see some reports using this grading system. Is there a recommendation from ASE?”
The American Society of Echocardiography (ASE) released a valvular regurgitation guideline paper in 2017. Although we now categorize MR as either mild, moderate or severe their is still a subcategory of grade I-IV. “Quantitation of regurgitation can further subclassify regurgitation into four grades, with grade III having some overlap with characteristics of severe MR, hence the need for an integrative approach” (p.333)
Many people find the quantification algorithm from the ASE guideline paper daunting. Bear with me as I break down Grade III MR. The key to determining if grade III MR is classified as moderate or severe MR is based on specific criteria for severe MR.
The quantification algorithm starts by seeing if we can quickly rule-out mild or severe MR. To meet the severe MR criteria without additional advanced quantification you must meet four or more of the criteria listed in the Severe MR criteria box.
If you do not meet four or more (>4) of these criteria, it will be necessary to calculate the EROA, RVol, and RF. You will note there are two tables leading to Moderate MR based on the value of these measurements.
As you can see by the table above a combination of advanced quantification measurements and specific criteria for severe MR determines if grade III MR is moderate or severe. Therefore, reporting grade III MR would require an additional statement on severity. For example, ‘Grade III Moderate MR’ or ‘Grade III Severe MR’.
Grading MR Severity with Echo requires a severity statement (mild, moderate, severe) A sub-category statement using grade I – IV may also be used. Since many doctors are familiar with using the numbered grading scale it will be necessary to state if grade III MR is moderate or severe.
Thank you for your question. To all of our readers…don’t be shy about asking questions! We are here to serve you and provide the resources you need to improve your understanding of echo techniques.
American Society of Echocardiography (ASE). April 2017. Noninvasive Evaluation of Native Valvular Regurgitation. https://www.asecho.org/wp-content/uploads/2017/04/2017VavularRegurgitationGuideline.pdf