Variabilidade da frequência cardíaca e a dinâmica miocárdica em cães com degeneração mixomatosa da valva mitral submetidos a um programa de condicionamento físico

• Autor(a) principal: Adams, Felipe Kunz [UNESP]
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/127975; http://www.athena.biblioteca.unesp.br/exlibris/bd/cathedra/17-09-2015/000849663.pdf
• topic: Cão; Coração - Doenças; Exercícios físicos; Esteira rolante; Ecocardiografia; Valvula mitral; Echocardiography

The myxomatous mitral valve disease (MMVD) is the most common heart disease in dogs. Although treatment strategies change according to the stage of the disease, exercise programs are not part of the standard therapy of the disease. In human beings, it has been demonstrated that proper training can be beneficial as adjunctive treatment of certain cardiovascular diseases. This study evaluated the effects of systematic training on a treadmill in dogs with MMVD. Nineteen dogs were selected and divided into four groups according to the severity of illness (based on the size of the left atrium-to-aorta ratio - Group A: control; Group B: LA/Ao<1.4; Group C: LA/Ao 1.4 to 1.8, and Group D: LA/Ao>1.8). The incremental exercise test was performed to detect the lactate threshold. Eight consecutive weeks of training were performed based on 70% of the lactate threshold velocity. The animals were evaluated for the heart rate variability, as well as myocardial dynamics, by standard and tissue Doppler echocardiography. Test for residual normality, analysis of variance, and Tukey's test were all used to compare the means of several parameters. Statistical analyses were performed at a level of significance of 5%. Exploratory multivariate statistical analysis was used for the extraction of factors, according to the Kaiser criteria. The echocardiography results showed increased left ventricular internal diameter in diastole eight weeks after training as compared to the baseline value in group C, as well as an increased interventricular septum in systole at four weeks and eight weeks as compared to the baseline value in group A. Heart rate variability data revealed a reduction in standard deviation of all RR intervals (SDNN) in C and D groups in comparison with group A at baseline. Also, after two and four weeks of training significant differences were found to exist between all groups compared to group A. From standard deviations of the mean values of ...