The data on the influence of sedative alpha-2- agonists - xyla and meditine on functional condition of cardiovascular system of the cat are presented in the study: heart rate, speed of passing of an im-pulse on carrying-out heart system, the existence of violations of heart rhythm. The research was con- ducted on clinically healthy cats coming to educa- tional and scientific methodical veterinary center of "Vita" of Krasnoyarsk SAU. Two groups of animals up to 30 heads in each were created. The cats of the first group were injected with xyla in a dose of0.15 ml on 1 kg of weight one time intramuscularly, the cats of the second group - meditine 0.5 ml on 5 kg of weight intramuscularly once. In all cats, se- dated with xyla, steady decrease in heart rate to 90-112 beats/min (at a rate of 140 beats/min) was established, the lengthening of the R-R interval by 1.5-2 times (from 0.65 up to 0.9 seconds), as well as a significant increase in the time of repolariza- tion of the heart muscle (t wave and t-R interval -0.06 seconds and from 0.26 seconds respectively). Also in the cats of the first group, heart rhythm dis- turbance was noted. In the cats of the second group, which received sedation meditine, bradyarrhythmia was detected only in 18 cats, which amounted to 60 %. In 40 % of cats of the second group the electrocardiogram showed no deviations from physiological indicators. Against the background of the introduction of xyla in all cats on the ECG, a slowdown in the pulse conduction sys- tem of the heart from sinoauricular node to atrioventricular junction was revealed, which was manifested by an extension of the p-Q interval, with the introduction of meditine, the duration of this in- terval corresponded to the norm. When applying xyla and meditine in cats atrioventricular block was not registered.