Avaliação da frequência cardíaca e a variabilidade da frequência cardíaca em cães braquicefálicos e mesocefálicos em ambiente hospitalar e domiciliar

Abstract

Brachycephalic dogs, due to their anatomical conformation, may present more pronounced respiratory and cardiovascular alterations in response to stressors related to probable anatomical abnormalities and vagal stimulation. It is assumed that the response to stressful stimuli may differ between brachycephalic and mesocephalic dogs. Therefore, methods such as the assessment of heart rate and its variability can be used as evaluative methods for discerning the alterations caused in dogs due to the diversification of environments. Therefore, the research sought to evaluate how the environment can influence the cardiovascular parameters of brachycephalic and mesocephalic dogs, submitted to electrocardiographic examination in a hospital environment and at home. As results, the study showed that brachycephalic dogs had a higher mean minimum heart rate in a hospital environment (p=0.0115) with 76 bpm when compared to the home environment with 68 bpm. However, when analyzing the mean heart rate, the group of brachycephalic dogs did not present different values between environments (p=0.2316) with 112 bpm in a hospital environment and 100 bpm at home, being analogous to the maximum heart rate respectively, not obtaining different values between environments (p=0.9200), with 172 bpm in a hospital environment and 169 bpm at home. In the analysis of mesocephalic dogs, they presented a higher mean minimum heart rate in a hospital environment (p = 0.0018) of 97 bpm when compared to the home environment with 71 bpm, being similar to the mean heart rate, with disparity between the hospital environment (p = 0.0189) with 138 bpm compared to the home environment with 111 bpm, however, in the analysis of the maximum heart rate, this did not demonstrate disparity values (p = 0.0650) between the two environments, presenting 178 bpm in a hospital environment and 154 bpm at home. Concomitantly, the analysis of the heart rate variability of mesocephalic dogs showed that there were variations in the Cardiovagal Index markers of this group, being lower in a hospital environment (p= 0.026). In addition, variations were evidenced in the Cardio Sympathetic Index markers, obtaining higher values in a hospital environment (p= 0.014), as well as disparity values in Alpha 1 were highlighted, being higher in a hospital environment (p= 0.010), when compared to the home environment. In contrast, the analysis of the heart rate variability of brachycephalic dogs did not demonstrate variations in the linear and non-linear markers of the two environments studied. Therefore, this study demonstrated that the environment has a certain influence on the heart rate and its variability of dogs and may be linked to factors such as stress and anxiety related to handling, obtaining as a response a cardiovascular modulation of the dogs.