RA/RV Calculator

Quantitative Right Heart Morphology & Function

Echocardiographic assessment of the right heart integrates chamber dimensions with multiparametric evaluation of longitudinal and global systolic performance according to ASE 2025 guidelines.

1. Right Atrial (RA) Size

• RA Volume Index (RAVI): Normal ≤ 29 mL/m²; mild dilatation 30–36 mL/m²; moderate 37–41 mL/m²; severe > 41 mL/m².
• RA Area (A4C): Normal < 19 cm²; mild 19–22 cm²; moderate 23–24 cm²; severe > 24 cm².

2. Right Ventricular (RV) Dimensions (End-diastole)

• RVOT PLAX: Normal ≤ 33 mm.
• RVOT1 PSAX (above aortic valve): Normal ≤ 34 mm.
• RVOT2 PSAX (below pulmonary valve): Normal ≤ 29 mm.
• RV basal (A4C): Normal ≤ 41 mm.
• RV mid (A4C): Normal ≤ 35 mm.
• RV longitudinal: Normal ≤ 82 mm.

3. Systolic RV Function Metrics

• TAPSE: Normal > 17 mm. Mildly reduced 13–17 mm; moderately reduced 11–12 mm; severely reduced < 10 mm.
• TDI S' (lateral tricuspid annulus): Normal > 9.5 cm/s.
• FAC (Fractional Area Change): Normal > 35%; mildly reduced 30–35%; moderately reduced 23–29%; severely reduced < 23%.

4. Ventriculo-Arterial Coupling (TAPSE/sPAP)

The TAPSE/PASP ratio (normal > 0.36 mm/mmHg) evaluates RV contractile compensation against pulmonary vascular afterload and serves as an established prognostic marker in pulmonary hypertension.