Tricuspid Stenosis: Echocardiographic Assessment

Tricuspid stenosis (TS) is narrowing of the tricuspid valve orifice that impedes diastolic blood flow from the right atrium to the right ventricle. It is a relatively rare valve lesion, and echocardiography is the primary tool for its diagnosis, severity assessment, and evaluation for accompanying valve disease. This tutorial covers etiology and echocardiographic assessment, informed by the 2025 ESC/EACTS valvular heart disease guideline, which includes a dedicated tricuspid stenosis section not present in the 2020 ACC/AHA guideline.

Etiology

• Rheumatic fever — the most common cause worldwide, and, importantly, tricuspid rheumatic disease more often presents as a combined stenosis-and-regurgitation pattern rather than pure stenosis (unlike the mitral valve, where pure rheumatic stenosis is more typical). This mixed pattern limits how often balloon valvuloplasty is a feasible treatment option for rheumatic TS.
• Carcinoid heart disease — a distinctive, non-rheumatic cause: serotonin-mediated proliferation causes fibroblasts and extracellular matrix to deposit on the valve leaflets and subvalvular apparatus, thickening and fixing them.
• Congenital anomalies — including Ebstein’s anomaly, the most recognized congenital tricuspid abnormality
• Enzymatic/infiltrative disorders — Whipple’s disease and Fabry’s disease are both recognized, less common causes
• Right atrial tumors or thrombus, and endocardial fibroelastosis
• Rare causes — certain medications (e.g., fenfluramine, methysergide), cardiac implantable electronic device (CIED) lead-associated thrombus obstructing the valve, and infective endocarditis with large vegetations

Signs and Symptoms

Because TS obstructs flow into the right side of the heart, symptoms reflect systemic venous congestion rather than pulmonary congestion:

• Peripheral edema
• Abdominal swelling and ascites
• Right upper quadrant pain, from hepatic congestion
• Jaundice
• Notably, minimal evidence of pulmonary congestion — a useful distinguishing feature from left-sided valve disease, since blood is backing up behind the tricuspid valve rather than the mitral valve

Cardiac Auscultation

• An opening snap, best heard along the lower left sternal border
• A diastolic rumble — a low-pitched murmur that characteristically increases with inspiration (Carvallo’s sign), reflecting increased venous return to the right heart during inspiration

Diagnostic Testing Beyond Echocardiography

• ECG — right atrial enlargement; biatrial enlargement if concomitant mitral stenosis is present; atrial fibrillation is common
• Chest X-ray — right atrial enlargement

Echocardiographic Findings

M-Mode

• Thickened tricuspid valve leaflets
• Decreased E-F slope of the tricuspid valve, reflecting impaired early diastolic opening
• Anterior motion of the posterior leaflet during diastole

2D Echocardiography

• Thickened leaflets, particularly at the leaflet tips
• Diastolic doming of the tricuspid valve — a “hockey stick” appearance, directly analogous to the classic sign of rheumatic mitral stenosis
• Right atrial enlargement
• A dilated inferior vena cava, reflecting elevated right atrial pressure

Doppler Echocardiography

• Turbulent flow through the valve in diastole
• An increased inflow velocity (> 1.0 m/s) at the leaflet tips
• A decreased E-F slope on the Doppler inflow tracing, mirroring the M-mode finding
• Pressure half-time (PHT) can be used to estimate tricuspid valve area, using the same relationship applied to the mitral valve:

Tricuspid valve area (cm²) = 220 / PHT (ms)

This method is less well-validated for the tricuspid valve than for the mitral valve, since the tricuspid valve operates at lower pressures and flow rates, and PHT-derived estimates should be interpreted alongside the other findings below rather than in isolation.

• Mean pressure gradient across the valve should be determined directly
• Assess for the presence and severity of any accompanying tricuspid regurgitation, since — as above — mixed disease is common

Severity Assessment

The 2025 ESC/EACTS guideline states that a mean diastolic transvalvular gradient greater than 5 mmHg at a normal heart rate indicates severe TS. This is the specific, guideline-stated quantitative threshold for severity.

A tricuspid valve area below approximately 1.0–2.0 cm² is commonly cited in echocardiography teaching as corresponding to severe stenosis (normal tricuspid valve area is roughly 7–9 cm², substantially larger than the mitral valve given the larger normal annulus), though this specific area-based cutoff is less rigorously standardized in the literature than the gradient-based criterion above — favor the mean gradient when the two seem to disagree.

Important Considerations

• TS rarely occurs as an isolated lesion. It is very often accompanied by mitral stenosis, and sometimes aortic or pulmonic valve disease — a comprehensive evaluation of all four valves for rheumatic involvement is essential whenever TS is identified.
• Because rheumatic TS commonly presents with a mixed stenosis-regurgitation pattern, percutaneous balloon valvuloplasty is a less broadly applicable option here than it is for pure rheumatic mitral stenosis — surgical management is more often required.
• Right heart hemodynamics are more sensitive to loading conditions (volume status, respiratory variation) than the left heart, so integrate Doppler findings with the overall clinical volume status rather than reading any single measurement in isolation.