Fig 1.
Orangutan positioning for echocardiographic examination and probe placement.
Orangutan positioning for echocardiographic examination (A) and probe placement (B) for obtaining the apical long-axis views (1) and the parasternal short-axis view at the level of the aortic valve (2). Fig 1B: courtesy of Emmanuel Baril (Ménagerie, le zoo du jardin de plantes, Paris).
Fig 2.
Representative apical 4-chamber view obtained from Borneo orangutans involved in the study.
This view allows to place the M-mode cursor through the lateral mitral annulus for measurement of mitral annular motion (MAM, A) and to obtain transmitral flow recordings using pulsed-wave Doppler mode (B). Video loops of this view can also be used for left ventricular (C) and left atrial measurements (D). Fig 2C and 2D respectively show measurements of the end-systolic left ventricular diameter and end-diastolic left atrial volume (see text for explanation). E and A: peak velocity of early and late diastolic transmitral flows, respectively; LA: left atrium; LV: left ventricle.
Fig 3.
Representative speckle tracking imaging examination performed from the apical 4-chamber view in a Borneo orangutan.
The left ventricular endocardial border is traced and a region of interest including left ventricular myocardial walls is automatically drawn (A). The software algorithm then automatically separates left ventricular myocardial walls into 6 equidistant segments (A and B). The tracking quality is displayed for each segment (A). Fig C shows on the right the 6 left ventricular longitudinal strain versus time curves (corresponding to the 6 myocardial segments) during a single cardiac cycle. This representative case demonstrates that all the 6 LV segments undergo a relatively homogenous systolic myocardial shortening during systole (negative strain). The corresponding color map below displays the change in strain over time in each segment during the same single cardiac cycle. The peak systolic strain is displayed in each of the six segments on the two-dimensional color-coded view (left). Fig D shows the mean left ventricular longitudinal strain versus time curve. In this case, the peak systolic strain value (StS4chv) is—16.9%. LA: left atrium; LV: left ventricle.
Fig 4.
Representative apical 5-chamber view obtained from Borneo orangutans involved in the study.
This view allows to obtain aortic flow recordings using continuous-wave Doppler mode (A). Video loops of this view can also be recorded for post-processing measurements of the left atrium and the aorta using the anatomic M-mode technique (B). For this purpose, the M-mode line is positioned perpendicular to left atrial and aortic walls (B). Lastly, by slightly tilting the probe from this position, the M-mode line can also be placed through the lateral segment of the tricuspid annulus for optimal measurement of the tricuspid annular plane systolic excursion (TAPSE; C). Ao: aorta; LA: left atrium; LV: left ventricle.
Fig 5.
Representative speckle tracking imaging examination performed from the apical 5-chamber view in a Borneo orangutan.
As described in Fig 3 for the apical 4-chamber view, the left ventricular endocardial border has been traced and a region of interest including left ventricular myocardial walls has been automatically drawn. Six equidistant myocardial segments have been defined. Fig A shows on the right the 6 left ventricular longitudinal strain versus time curves (corresponding to the 6 myocardial segments) during a single cardiac cycle. This representative case demonstrates that all the 6 LV segments undergo a relatively homogenous systolic myocardial shortening during systole (negative strain), with the corresponding color map below displaying the change in strain over time in each segment during the same single cardiac cycle, and with the peak systolic strain displayed in each segment on the two-dimensional color-coded view (left). Fig B shows the mean left ventricular longitudinal strain versus time curve. In this case, the peak systolic strain value (StS5chv) is—20.8%. The global left ventricular systolic strain is then assessed by averaging mean peak systolic strain values obtained from the apical 4- and 5-chamber view, i.e., StS4chv and StS5chv, respectively. LA: left atrium; LV: left ventricle.
Table 1.
Mean ± standard deviation (SD), minimum (Min) and maximum (Max) values of repeated measurements of two-dimensional (n = 12), M-mode (n = 3) and anatomic M-mode (n = 3) echocardiographic variables (n = 18) obtained by a trained observer in 4 Borneo orangutans (Pongo pygmaeus pygmaeus) from 96 transthoracic examinations, BO1 to BO3 being the females and BO4 the male.
Table 2.
Mean ± standard deviation (SD), minimum and maximum values of repeated measurements of Doppler (n = 7) and STE (n = 3) variables (n = 10) obtained by a trained observer in 4 Borneo orangutans (Pongo pygmaeus pygmaeus) from 96 transthoracic examinations.
Table 3.
Within-day and between-day variability, expressed as standard deviations (SD) and coefficients of variation (CV), of two-dimensional (n = 12), M-mode (n = 3) and anatomic M-mode (n = 3) echocardiographic variables (n = 18) obtained by a trained observer in 4 Borneo orangutans (Pongo pygmaeus pygmaeus) from 96 transthoracic examinations.
Table 4.
Within-day and between-day variability, expressed as standard deviations (SD) and coefficients of variation (CV), of Doppler (n = 7) and STE (n = 3) variables (n = 10) obtained by a trained observer in 4 Borneo orangutans (Pongo pygmaeus pygmaeus) from 96 transthoracic examinations.