Heart rate variability in dogs with myxomatous mitral valve disease: a contemporary review

Abstract

The autonomic nervous system is responsible for regulating heart rate and adapting it to the metabolic and tissue needs of the organism. Heart rate variability (HRV) can be analyzed to assess cardiac autonomic activity in dogs with myxomatous mitral valve disease (MMVD), the main chronic acquired heart disease affecting this species. HRV measurement is performed through the analysis of electrocardiographic recordings and can indicate prognosis and predict the risk of death from cardiovascular diseases in animals and humans. Evaluation of different variables has shown that HRV is reduced in patients with congestive heart failure. In asymptomatic dogs with early-stage MMVD, there is still no scientific certainty regarding a reduction in HRV. Pharmacological and non-pharmacological treatments, such as exercise training, can increase cardiac autonomic modulation and parasympathetic activity in dogs with MMVD. The assessment of HRV in animals with MMVD is important for a better understanding of disease progression and determining prognosis. Understanding the pathophysiological mechanisms involved in MMVD and congestive heart failure is essential, and assessing HRV in animals with MMVD is important for a better understanding of disease progression and therapeutic interventions. Therefore, this literature review covers the variables used to evaluate HRV and its correlation with DMD in its different stages and treatments from different recent studies on the subject.