Table 7.

Inter- and intra-observer variability for the different LA quantification methods, dense spontaneous spontaneous echocardiographic contrast and left atrial appendage thrombus

Inter-observer variability	A vs B	A vs C	B vs C
LA AP Diameter (mean ± SD,%)	1.05 ± 0.19	1.04 ± 0.2	1.04 ± 0.18
LA Area 4C (mean ± SD,%)	1.03 ± 0.23	1.04 ± 0.24	1.02 ± 0.21
LA Ellipsoid Volume (mean ± SD,%)	1.12 ± 0.36	1.1 ± 0.36	1.08 ± 0.33
LA 1P Area-Lenght Volume (mean ± SD,%)	1.09 ± 0.44	1.11 ± 0.47	1.06 ± 0.41
LA 2P Area-Lenght Volume (mean ± SD,%)	1.05 ± 0.28	1.07 ± 0.28	1.03 ± 0.27
Dense SEC	R = 0.797, p < 0.001	R = 0.849, p < 0.001	R = 0.841, p < 0.001
LAA Thrombus	R = 0.857, p < 0.001	R =1, p < 0.001	R = 0.857, p < 0.001
Intra-observer variability	A	B	C
LA AP Diameter (mean ± SD,%)	1 ± 0.08	1 ± 0.08	1 ± 0.07
LA Area 4C (mean ± SD,%)	1.01 ± 0.11	1.01 ± 0.09	1.01 ± 0.1
LA Ellipsoid Volume (mean ± SD,%)	1.01 ± 0.1	01.01 ± 0.1	0.98 ± 0.11
LA 1P Area-Lenght Volume (mean ± SD,%)	1.03 ± 0.24	1.02 ± 0.2	1.03 ± 0.22
LA 2P Area-Lenght Volume (mean ± SD,%)	1.01 ± 0.15	1.01 ± 0.15	1.02 ± 0.14
Dense SEC	R =0.901, p < 0.001	R =1, p < 0.001	R = 1, p < 0.001
LAA Thrombus	R = 1, p < 0.001	R = 1, p < 0.001	R =1, p < 0.001

Legend: LA – left atrial; LAA – left atrial appendage; SEC – spontaneous echocardiographic contrast; 4C – 4-chamber; 1P – single-plane; 2P – biplane.

A, B and C represent the three different echocardiographers.

For LA measurements are presented the results of Bland-Altman analysis, expressed as mean ± SD of the ratio of the measurements in comparison. For dense spontaneous spontaneous echocardiographic contrast and left atrial appendage thrombus are presented the variability is presented as a correlation.