Department of Clinics, Faculty of Veterinary Medicine, University of Applied Life Sciences and Environment 'Ion Ionescu de la Brad', Iași, Romania.
Department of Clinics, Faculty of Veterinary Medicine, University of Applied Life Sciences and Environment 'Ion Ionescu de la Brad', Iași, Romania.
Vet J. 2021 Aug;274:105704. doi: 10.1016/j.tvjl.2021.105704. Epub 2021 Jun 5.
Mitral valve disease (MVD) progression is associated with autonomic nervous system (ANS) imbalance. This study hypothesized that sympathetic and parasympathetic tones would be altered with MVD progression. ANS activity was assessed among different MVD classes in untreated dogs. This cross-sectional retrospective study included 29 healthy control dogs and 71 dogs with MVD divided according to American College of Internal Medicine (ACVIM) guidelines. Heart rate variability (HRV) analyses utilised time and frequency domains and were derived from 5 min, six-lead electrocardiogram recordings of sinus rhythm or respiratory sinus arrhythmia. While all time domain-related HRV parameters decreased with disease severity, only dogs in stage C exhibited significantly lower values (P < 0.05). High frequency (HF) band values decreased more than low frequency (LF) band values as disease severity increased (P < 0.05). The LF/HF ratio also progressively increased with MVD severity. A negative correlation was observed between HRV parameters and La/Ao ratio when the entire MVD case population was pooled (P < 0.05). Both sympathetic and parasympathetic tones were altered in dogs with MVD before clinical signs were observed and prior to the development of cardiomegaly. This is the first HRV study in untreated dogs with MVD. Investigating ANS imbalances preceding subclinical left-sided cardiomegaly in dogs with MVD should be considered in future age-matched, longitudinal studies to determine the potential benefits of early vagal tone augmentation in high-risk canine patients.
二尖瓣疾病（MVD）的进展与自主神经系统（ANS）失衡有关。本研究假设，随着 MVD 的进展，交感和副交感神经张力会发生改变。在未经治疗的犬中，评估了不同 MVD 类别的 ANS 活性。这项横断面回顾性研究包括 29 只健康对照犬和 71 只根据美国内科医师学会（ACVIM）指南分为 MVD 的犬。心率变异性（HRV）分析利用了时域和频域，并从窦性节律或呼吸窦性心律失常的 5 分钟 6 导心电图记录中得出。虽然所有与时间相关的 HRV 参数都随着疾病严重程度的降低而降低，但只有 C 期的犬表现出显著降低（P < 0.05）。随着疾病严重程度的增加，高频（HF）波段值的降低幅度大于低频（LF）波段值（P < 0.05）。LF/HF 比值也随着 MVD 严重程度的增加而逐渐增加。当整个 MVD 病例群体被汇集时，观察到 HRV 参数与 La/Ao 比值之间存在负相关（P < 0.05）。在出现临床症状和心脏肥大发展之前，患有 MVD 的犬的交感和副交感神经张力都发生了改变。这是首例未经治疗的 MVD 犬 HRV 研究。在未来的年龄匹配、纵向研究中，应考虑在患有 MVD 的犬出现亚临床左侧心脏肥大之前，调查 ANS 失衡，以确定早期增加迷走神经张力对高危犬患者的潜在益处。
