Mitral Stenosis

Mitral Stenosis

Evaluate MS severity anchored on mitral valve area. Mean gradient reflects hemodynamic burden — it does not independently classify severity. PHT method accuracy, AF, low-flow state, and etiology all shape the interpretation.

Primary guideline:ACC/AHA VHD 2020

Assess MS severity

Classify MS severity using ACC/AHA 2020 integrated criteria. MVA-anchored classification with PHT method accuracy warnings, AF and low-flow confounders, and etiology modifier flags.

Open MS Severity Tool

MS Intervention Navigator

Evaluate intervention pathways for significant MS based on severity, symptom status, morphology, and clinical context.

Open MS Intervention Navigator

Learn the concepts

Why MVA anchors the grade, what makes PHT unreliable, and how discordant hemodynamics should be interpreted.

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Clinical context

MVA is the primary severity anchor — not mean gradient

MS severity is classified by mitral valve area. Mean gradient reflects the hemodynamic burden at a given flow and heart rate — not the anatomic severity of the valve lesion. A low gradient does not exclude severe MS if MVA is ≤ 1.5 cm².

PHT is commonly used but context-dependent

Pressure half-time estimates MVA from transmitral pressure decay. Its accuracy is reduced by coexistent AR, post-valvotomy state, tachycardia, LV diastolic dysfunction, and coexistent MR. When these are present, planimetry or 3D echocardiography provides more reliable MVA.

Etiology shapes intervention complexity — not the severity grade

Rheumatic, MAC-related, prosthetic, and congenital MS all produce MVA obstruction, but intervention approach, eligibility, and complexity differ substantially. The severity grade is MVA-anchored regardless of etiology; modifier flags highlight where standard pathways do not apply.