Introduction: Older small breed dogs are considered at risk for heart failure secondary to chronic mitral valve disease. However, few data are available on the onset of this disease in such dogs. This study was performed to determine if auscultation alone can be used to eliminate clinically relevant mitral valve regurgitation seen in echocardiography in Dachshund dogs. Material and Methods: Clinical and echocardiographic data were obtained from 107 dogs without heart murmurs. Results: The study revealed that 63.6% of the dogs had mitral regurgitation. Numbers increased with age and a larger percentage of male Dachshunds were affected than female Dachshunds. Mitral valve prolapse and thickening were mild, and the regurgitant area inextensive in most dogs. Conclusions: The study shows that mitral valve regurgitation is prevalent (63.6%) in Dachshunds without heart murmurs. Typical lesions often become apparent during echocardiographic examinations in dogs under 5 years of age.

Myocardial dysfunction occurs in cats with hypertrophic cardiomyopathy (HCM), but little is known about the early stages of the disease. Strain imaging echocardiography is a method that enables the quantitative assessment of myocardial function and deformity, allowing the characterization of systolic dysfunction. The objective of this study was to assess systolic function using strain imaging echocardiography in Maine coon cats genetically tested for the A31P mutation in the MYBPC3 gene, with and without ventricular hypertrophy. For this purpose, 57 Maine coon cats of both genders, with an unknown status regarding the mutation at inclusion, were included prospectively and evaluated by conventional and strain imaging echocardiography. Comparisons were made among cats without hypertrophy (n = 45), suspect cats (n = 7), and cats with hypertrophic cardiomyopathy (n = 5), and also between the heterozygous for the mutation group (n = 26) and the negative for the mutation group (n = 28). Finally, in the group of phenotypically normal cats, heterozygous cats carrying the mutation were compared to cats without the mutation. Strain values were compared among the groups (blinded prospective study). While echocardiography demonstrated normal contractility, strain values (middle of the septum) were lower in HCM cats. Strain values (base of anterior wall of the left ventricle) were lower in heterozygous than in negative cats, even before hypertrophy. Negative correlation was observed between some values of myocardial strain and thickness. While strain imaging echocardiography was able to detect systolic abnormalities, despite apparent normality on conventional echocardiography, it was not able to identify cats that carry the A31P mutation in the MYBPC3 gene. Strain imaging echocardiography could be a useful tool, however, for detecting systolic alterations in HCM cats with an apparently normal systolic function or for detecting alterations in normal carriers of the MYBPC3 gene mutation.

OBJECTIVE To evaluate the accuracy of cardiac output (CO) estimated by use of ECG-gated multidetector CT (MDCT) and 1-, 2-, and 3-D echocardiography and by use of thermodilution. ANIMALS 6 healthy hound-cross dogs. PROCEDURES Electrocardiogram-gated contrast-enhanced 64-slice MDCT and 1-, 2-, and 3-D echocardiography were performed on each dog. The CO for ECG-gated MDCT was calculated as volumetric measurements of stroke volume multiplied by mean heart rate. Echocardiographic left ventricle end-diastolic volumes and end-systolic volumes were measured by use of the Teichholz method (1-D echocardiography) and a single-plane method of disks (2-D echocardiography). Real-time 3-D echocardiographic left ventricle volumes were measured with 3-D functional analysis software on right long-axis and left apical views. The CO of each dog was measured in triplicate by use of thermodilution. Mean CO values, correlations, and limits of agreement for MDCT, echocardiographic modalities, and thermodilution were compared. RESULTS CO measured by use of MDCT, 2-D echocardiography, and 3-D echocardiography had the strongest correlations with CO measured by use of thermodilution. No significant difference in CO was detected between MDCT, any echocardiographic method, and thermodilution. Bland-Altman analysis revealed a systematic underestimation of CO derived by use of MDCT, 2-D echocardiography, and 3-D echocardiography. CONCLUSIONS AND CLINICAL RELEVANCE Use of MDCT, 2-D echocardiography, and 3-D echocardiography to measure CO in healthy dogs was feasible. Measures of CO determined by use of 3-D echocardiography on the right long-axis view were strongly correlated with CO determined by use of thermodilution, with little variance and slight underestimation.

OBJECTIVE To determine effects of a combination of acepromazine maleate and butorphanol tartrate on conventional echocardiographic variables and on strain values obtained by use of 2-D speckle tracking echocardiography (STE) in healthy dogs. ANIMALS 18 healthy medium- and large-size adult dogs. PROCEDURES Transthoracic echocardiographic examination (2-D, M-mode, color flow, spectral Doppler, and tissue Doppler ultrasonography) and high-definition oscillometric blood pressure measurement were performed before and after dogs were sedated by IM administration of a combination of acepromazine (0.02 mg/kg) and butorphanol (0.2 mg/kg). Adequacy of sedation for echocardiographic examination was evaluated. Circumferential and longitudinal global and segmental strains of the left ventricle (LV) were obtained with 2-D STE by use of right parasternal short-axis and left parasternal apical views. Values before and after sedation were compared. RESULTS The sedation combination provided adequate immobilization to facilitate echocardiographic examination. Heart rate and mean and diastolic blood pressures decreased significantly after dogs were sedated. A few conventional echocardiographic variables differed significantly from baseline values after sedation, including decreased end-diastolic LV volume index, peak velocity of late diastolic transmitral flow, and late diastolic septal mitral and tricuspid annulus velocities, increased ejection time, and increased mitral ratio of peak early to late diastolic filling velocity; global strain values were not affected, but 1 segmental (apical lateral) strain value decreased significantly. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that acepromazine and butorphanol at the doses used in this study provided sedation adequate to facilitate echocardiography, with only mild influences on conventional and 2-D STE variables.