Mitral regurgitation — classify first, then grade
Primary and secondary MR use different severity thresholds and follow different intervention pathways. Applying the same criteria to both leads to misclassification. This hub starts with that distinction.
Primary MR (structural valve disease)
MVP, flail leaflet, rheumatic — the valve itself is diseased
Primary MR Severity
Integrate EROA, regurgitant volume, regurgitant fraction, and vena contracta to grade severity. Classify concordant severe, supported severe, and discordant patterns. Add LV function and symptoms to assign ACC/AHA stage (C1 / C2 / D).
Primary MR Intervention
Evaluate ACC/AHA indication class for MV repair or replacement and surgical timing based on confirmed severity, symptoms, and LV function.
Secondary MR (functional MR)
Secondary MR is ventricular or atrial remodeling disease. Severity assessment comes first; intervention decisions require symptoms, LV size/function, pulmonary pressure, and HF therapy context.
Secondary MR Severity
ACC/AHA 2020 applies the same quantitative severe range to secondary MR as to primary MR, but the clinical interpretation differs substantially. Severity must be assessed in the context of LV function, symptoms, pulmonary pressure, and GDMT response — not quantitative values alone.
Secondary MR Intervention
Intervention decisions in secondary MR are complex — they sit at the intersection of heart failure management, LV remodeling, and valve disease treatment.
Learn — Primary MR
Learn — Secondary MR
Secondary MR is ventricular disease, not a valve-first problem
EROA 0.20 cm² is a prognostic signal, not the severe threshold
GDMT can cause MR regression — it is not a placeholder
Valve intervention does not fix the ventricle
COAPT vs MITRA-FR: why the trials diverged
Atrial functional MR — different from ventricular functional MR
Cases — Secondary MR
Why classification comes first
Primary and secondary MR: same criteria, different clinical meaning
ACC/AHA 2020 applies the same quantitative severe range to both primary and secondary MR. But the same EROA value does not carry the same clinical meaning — secondary MR must be interpreted in the context of LV function, symptoms, and GDMT response, not just the measured ERO alone.
Primary targets the valve; secondary targets the left ventricle
In primary MR, the anatomical target is the valve itself (repair or replacement). In secondary MR, the primary intervention is the underlying LV dysfunction or ischemia. Treating the valve without addressing the driver often fails.
Practical implications for the perioperative anesthesiologist
When MR is identified on a preoperative TTE, the first question is: primary or secondary? Moderate-severe primary MR warrants cardiac surgery team communication. Secondary MR makes LV function the dominant monitoring concern.