Influência da altitude sobre parâmetros eletrocardiográficos, obtidos por meio do uso do "Holter" em cavalos de enduro em diferentes níveis de condicionamento físico

Abstract

TERMOS DE INDEXAÇÃO: Cardiologia em equinos, enduro equestre, altitude, condicionamento físico em equinos, sistema Holter. INTRODUÇÃOAs provas de enduro equestre realizadas em distância de até 160 km e em diferentes condições ambientais relacio- The aim of this paper was to study the influence of altitude on electrocardiographic parameters by means of the Holter system in 40 Arabian and Arabian crossbred horses, at different levels of physical conditioning, during training in trails of 15 km extension with mean speed of 15 km/h, and altitude varying from sea level to 1700m high. The electrocardiographic monitoring was obtained by standard electrocardiography at rest before exercise, and by dynamic electrocardiography with the Holter system applied during exercise and in post-exercise recovery. The animals presented sinusal rhythm, with a mean registered period for sinusal tachycardia of 32%, and 14% for sinusal bradycardia. Among the arrhythmias there was first-degree atrioventricular block (20%) and second-degree atrioventricular block (5%). Supraventricular ectopic arrhythmias were observed in two horses and only one showed ventricular arrhythmia. The number of asystoles was greater in less conditioned horses. Mean and maximal heart rates were influenced by altitude, with higher values in higher altitudes.INDEX TERMS: Cardiology in horses, endurance riding, altitude, physical conditioning in horses, Holter system.