Retrospective study of allometric relationship between heart rate, electrocardiographic parameters and bodyweight in dogs

ABSTRACT The allometric relationship between bodyweight (BW) and heart rate (HR) has been described as inversely proportional in domestic species, but that has been refuted. The relationship between HR and electrocardiographic variables is described in literature. However, studies about the variation and influence of factors on the hemodynamic and electrocardiographic parameters in dogs are not abundant. As the metabolic rate is defined as the production and dissipation of heat by the body surface area (BSA) in m², it is essential to define that relationship. A retrospective study was conducted to analyze the correlation between HR, ECG parameters and BW in dogs. One thousand electrocardiographic tracings were analyzed in addition to the ECG parameters and clinical data such as gender, age and bodyweight. The determination of BSA was performed as follows: BSA (m2) = (10.1 x bodyweight 0.67) X 10-4. When the unified groups were analyzed, there was a negative but weak correlation (r= -0.14, P< 0.0001) between bodyweight and HR. There were differences between weight groups regarding electrocardiographic variables. There is no allometric relationship between BW and HR in dogs. Weight was associated with changes in ECG variables.

摘要 家畜中体重（BW）与心率（HR）的异速生长关系曾被表述为负相关关系，但该结论已被推翻。现有文献已对心率与心电图变量间的关联进行了阐述，但针对犬类血流动力学与心电图参数的影响因素及其变异特征的相关研究仍较为匮乏。由于代谢率被定义为体表面积（BSA，单位：平方米）所产生并散发的热量，明确二者间的关联具有重要意义。本研究开展回顾性分析，旨在探究犬类心率（HR）、心电图（ECG）参数与体重（BW）之间的相关性。研究共纳入1000份心电图描记图，并同步收集心电图参数及性别、年龄、体重等临床数据。体表面积的计算公式如下：BSA（m²）= (10.1 × 体重^0.67) × 10^-4。对合并分组进行分析后发现，犬类体重与心率间呈负相关，但相关性较弱（r=-0.14，P<0.0001）。不同体重分组的心电图变量存在差异。犬类体重与心率间不存在异速生长关系，且体重与心电图变量的变化存在关联。