RV function training › Guides › RV size
RV size on echo
A normal RV is smaller than the LV in the apical 4-chamber view and does not form the apex. Size is measured at end-diastole in the RV-focused view, because small changes in transducer position change the apparent RV size a lot.
Diameters
| Measure | Where | Dilated (adults) |
|---|---|---|
| Basal diameter (RVD1) | Widest point in the basal third, just above the tricuspid annulus | >47 mm (men), >43 mm (women) |
| Mid-cavity diameter (RVD2) | Middle third, at the level of the papillary muscles | >42 mm (men), >35 mm (women) |
| Longitudinal (RVD3) | Tricuspid annular plane to the RV apex | >87 mm (men), >80 mm (women) |
| Proximal RVOT | Parasternal long axis | >43 mm (men), >40 mm (women) |
RV size values are not indexed and change with athletic training; RA area is normal up to 22 cm² in men and 19 cm² in women.
Quick visual checks
- RV:LV basal ratio: above 1 at end-diastole suggests RV dilatation (unreliable when the LV is also dilated); it is used, for example, in acute pulmonary embolism.
- Apex-forming RV: when the RV reaches or passes the LV apex, it is at least moderately dilated.
- Short axis: a dilated RV wraps further around the LV, and the septum may flatten (see the septal guide).
Wall thickness
RV free-wall thickness is measured at end-diastole, ideally in the subcostal view, below the tricuspid annulus, excluding trabeculations and epicardial fat. More than 5 mm means RV hypertrophy, usually from chronic pressure overload (pulmonary hypertension, pulmonary stenosis) and also in infiltrative disease.
In the simulator
Each case shows the patient's sex, and the RV counts as dilated when the basal diameter is above the BSE limit for that sex (47 mm in men, 43 mm in women). Values within 2 mm of the limit are borderline, and either answer is accepted.
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