Função ventricular direita em felinos domésticos saudáveis não sedados: avaliação pela ecocardiografia bidimensional e speckle tracking

Abstract

Over the years, domestic cats have gained each time more space in homes around the world. Behavioral characteristics of the species, the vertical growth of cities and other socioeconomic changes seem to contribute to the increase in the number of cats, which in some countries already surpasses that of dogs. Socioeconomic changes have also contributed to longer survival of pets and, consequently, to a higher incidence of chronic and degenerative diseases such as heart disease. Echocardiographic examination is an essential diagnostic modality for the assessment of cardiac patients, although most published studies focus on the left ventricle. Recent work has meant that the right ventricle has been underestimated, that it has great importance in circulatory physiology and that it is happening in the pathophysiology of cardiopulmonary and left-sided heart diseases. These findings encourage the realization of new studies that seek to better understand themselves according to the right Municipal Chambers and provide reference values. This study aims to evaluate the right ventricular function of clinically healthy cats in different age groups by means of conventional echocardiography and Speckle Tracking. 88 cats were included in the study. The animals were divided into three groups of different age groups, namely: G1 = pups (≤ 1 year); G2 = young adults (1 to 6 years), G3 = mature adults (7 to 10 years). In conventional echocardiography, linear measurements and myocardial function indices (fractional area variation, systolic excursion of the tricuspid annular plane, myocardial performance index and tissue Doppler) were performed. Two-dimensional speckle tracking were collected from the deformation indices and deformation rate of the free wall of the right ventricle. The linear measurements of the right atrium, right ventricle and free wall of the right ventricle differed between the groups, with lower values found in the offspring. Variables of myocardial function did not differ with age, but Speckle tracking echocardiography changes the highest strain values (G1: 27.12 ± 4.26; G2: 20.90 ± 2.59; G3: 23.57 ± 4.63; p <0.000) and strain rate (G1: 3.72 ± 0.72; G2: 2.88 ± 0.42; G3: 2.92 ± 0.71; p <0.0001) free wall images of the right ventricle in G1 animals. The evaluation of the deformation of the myocardial segments indicates that, in the free wall of the right ventricle of healthy cats, the basilar region has a greater contribution to myocardial contraction. In cats, conventional echocardiographic variations are determined by age, however puppies have higher formation values than adults. Preliminary reference values for healthy non-sedated cats can be derived from the results of this study.