Detection of subclinical left ventricular dysfunction by tissue Doppler imaging in horses with aortic regurgitation

Abstract

TDI showed significant differences in radial systolic and late diastolic myocardial velocity in horses with AR. This could indicate an altered LV function in these horses, but further research is needed to investigate the prognostic value of these measurements.

Diagnostic value of noninvasive pulse pressure measurements in Warmblood horses with aortic regurgitation

“…Because indices of LV size were included in the AR severity scoring system used to classify AR severity, it is logical that these indices would be different among the AR severity subgroups. The extent of LV enlargement in the AR severity subgroups was similar to that recently reported in other studies assessing the severity of AR using echocardiographic measurements . However, it is also clear that horses with severe AR show signs of LA enlargement indicating the hemodynamic relevance of severe AR resulting in increased preload of both the LV and LA.…”

“…The fact that indices of LV systolic function are not different among the AR severity subgroups highlights the difficulty in using these variables to judge the severity of AR, as has been described in 2 recent studies evaluating other methodologies to identify subtle changes in myocardial function. 42,43 Our study does not assert that NIBP measurements should replace echocardiography in the assessment of horses with AR. Rather, NIBP measurements, and particularly PP measurements, can provide additional information on the hemodynamic relevance of AR to guide practitioners in their assessment of these horses in both field and hospital settings.…”

“…The finding of increased MWT d and RWT d in horses with mild AR indicates that some concentric remodeling occurs in this population of horses, whereas the decreased RWT d seen in the horses with severe AR indicates that the chamber enlargement is becoming disproportionate to wall thickness. The fact that indices of LV systolic function are not different among the AR severity subgroups highlights the difficulty in using these variables to judge the severity of AR, as has been described in 2 recent studies evaluating other methodologies to identify subtle changes in myocardial function …”

“…The extent of LV enlargement in the AR severity subgroups was similar to that recently reported in other studies assessing the severity of AR using echocardiographic measurements. 10,42,43 However, it is also clear that horses with severe AR show signs of LA enlargement indicating the hemodynamic relevance of severe AR resulting in increased preload of both the LV and LA. The finding of increased MWT d and RWT d in horses with mild AR indicates that some concentric remodeling occurs in this population of horses, whereas the decreased RWT d seen in the horses with severe AR indicates that the chamber enlargement is becoming disproportionate to wall thickness.…”

Assessment of left ventricular function in horses with aortic regurgitation by 2D speckle tracking

“…Traditionally, fractional shortening (FS) or ejection fraction (EF) are used to estimate LV function, but in the compensated stage of the disease, FS and EF are unaltered [4,5]. Tissue Doppler imaging (TDI) is an ultrasound technique that has been validated in horses [6] and is able to detect alterations in radial myocardial function in horses with different grades of AR [7]. However, since apical images cannot be obtained in horses, longitudinal myocardial function cannot be evaluated by TDI.…”