Serial evaluation of cardiac biomarker NT-proBNP with speckle tracking echocardiography in a 6-year-old Golden Retriever dog with subaortic stenosis and dilated cardiomyopathy

Assessment of myocardial function in Retrievers with dilated cardiomyopathy using 2D speckle tracking echocardiography: a pilot study

Early diagnosis of canine dilated cardiomyopathy (DCM) is complicated by the presence of a prolonged asymptomatic phase, for which a comprehensive evaluation of myocardial function is essential. This pilot study was conducted to evaluate the myocardial function in dogs with DCM using two-dimensional speckle tracking echocardiography (2D-STE). Nine client-owned Retrievers with DCM and twelve client-owned clinically normal Retrievers were comparatively evaluated using standard echocardiography and 2D-STE. Dogs with DCM were characterized by significant dilation of the left ventricle (LV), thinning of the LV wall, and myocardial hypokinesis when compared to clinically normal dogs. The global strain analysis showed a significant reduction of strain in both radial and circumferential directions, and the regional strain analysis revealed a greater degree of myocardial dysfunction at the LV free wall in the circumferential direction in dogs with DCM. The regional strain analysis also demonstrated a difference in the pattern of contraction between dogs with DCM and clinically normal dogs. The results of this study illustrate the ability of 2D-STE to evaluate both global and regional myocardial function in dogs with DCM and show differences between dogs with DCM and clinically normal dogs.

Changes in echocardiographic indices and left ventricular strain values by two-dimensional speckle-tracking echocardiography following pre-anesthetic oral pimobendan administration compared with intravenous pimobendan in dogs

Introduction

The effects of pre-anesthetic single-dose oral pimobendan during inhalational anesthesia, including the comparison with the effects of single intravenous pimobendan under anesthesia, remain unexplored. Therefore, this study aimed to determine changes in hemodynamic and echocardiographic parameters induced by pre-anesthetic administration of oral pimobendan under isoflurane general anesthesia and to compare them with those induced by intravenous pimobendan.

Methods

Thirteen clinically normal dogs (4 laboratory and 9 client-owned dogs) with no clinical signs and not on any medical treatment were included. Anesthesia was performed three times: no pimobendan (Control), oral pimobendan (PIMO PO, 0.3 mg/kg), and intravenous pimobendan (PIMO IV, 0.15 mg/kg). Echocardiographic and hemodynamic parameters were monitored at 30-min intervals in all groups.

Results

Compared to the Control group, end-systolic volume index (ESVI) and normalized left ventricular internal diameter at end-systole (LVIDSN) were significantly lower, and fractional shortening (FS) and ejection fraction (EF) were significantly higher in the PIMO PO and IV groups (p < 0.001). Global radial strain (GRS) was significantly higher in the PIMO PO and IV groups (p = 0.015).

Conclusion

Under general anesthesia, oral pimobendan preserved LV systolic and myocardial function in a manner comparable to intravenous pimobendan. Pre-anesthetic administration of oral pimobendan can be used to compensate for cardiac systolic function in dogs who require therapeutic and diagnostic procedures under general anesthesia with potential risk of circulatory failure.

Role of Two-Dimensional Speckle-Tracking Echocardiography in Early Detection of Left Ventricular Dysfunction in Dogs

Simple Summary

Two-dimensional speckle-tracking echocardiography represents an advanced imaging technique that allows the analysis of global and regional myocardial function, cardiac rotation and synchronicity using deformation imaging. It has gained growing importance over the last decade, especially in human medicine as a method of evaluating myocardial function. This review aims to give an overview of the current understanding of this technique and its clinical applicability in the field of veterinary medicine with a focus on early detection of left ventricular dysfunction in dogs.

Abstract

Two-dimensional speckle-tracking echocardiography (2D–STE) is an advanced echocardiographic technique based on deformation imaging that allows comprehensive evaluation of the myocardial function. Clinical application of 2D–STE holds great potential for its ability to provide valuable information on both global and regional myocardial function and to quantify cardiac rotation and synchronicity, which are not readily possible with the conventional echocardiography. It has gained growing importance over the past decade, especially in human medicine, and its application includes assessment of myocardial function, detection of subclinical myocardial dysfunction and serving as a prognostic indicator. This review illustrates the fundamental concepts of deformation analysis and gives an overview of the current understanding and its clinical application of this technique in veterinary medicine, with a focus on early detection of left ventricular (LV) dysfunction in dogs.