RA is more difficult to estimate than LA. There are only a few echocardiographic measurements. In many cases, we look at the AP4CH to the ratio LA / RA: LA is normally slightly larger.
RA size
| MALE | FEMALE | |
|---|---|---|
| Mean ± SD | Mean ± SD | |
| RA minor axis diameter (cm/m²) | 1.9 ± 0.3 | 1.9 ± 0.3 |
| RA major axis diameter (cm/m²) | 2.5 ± 0.3 | 2.4 ± 0.3 |
| (2D echo) RA volume (mL/m²) | 21 ± 6 | 25 ± 7 |
RA pressure
| Inferior Vena Cava size | Estimation RA pressure |
|---|---|
| Normal <21mm, collaps >50% | 3 mmHg (range 0–5 mmHg) |
| Borderline <21mm, collaps <50% | 8 mmHg (range 5–10 mmHg) |
| Borderline >21mm, collaps >50% | 8 mmHg (range 5–10 mmHg) |
| Dilated >21mm, collaps < 50% | 15 mmHg (range 10- 20 mmHg) |
