Figure 7. Bland-Altman plot for
difference between LVESD in the prone versus the supine positions
The mean time of scan was significantly longer in the prone position as
compared to the supine position (12.5 vs 4.5 minutes, p <
0.001). In the supine position, the standard echocardiographic views
(PLAX, PSAX at the level of great vessels, mitral valve and papillary
muscles, apical and subcostal views) were feasible in all patients.
While in the prone position the PLAX view was feasible in 29 patients,
the PSAX view at the level of the the great vessels, mitral valve and
papillary muscles were feasible in 15, 27 and 20 patients respectively.
There was statistically significant difference in the quality of scans
in both positions, with the supine position having good quality scans as
compared to the prone position (p < 0.001). All supine studies
had good quality, while in the prone position 2, 23 and 4 studies had
good, fair and poor qualities respectively. Only in one study it was
non-diagnostic in the prone position due to obesity (BMI was 35.5
kg/m2). Figure 8 is a graphic demonstration of the frequencies of the
scan quality.
Figure 8.
Frequencies of scans quality in the prone position
studies