Valores eletrocardiográficos em saguis-de-tufo-preto (Callithrix penicillata)

Abstract

Pesq. Vet. Bras. 33(7):937-941, julho 2013 937 RESUMO.-O conhecimento de parâmetros cardíacos em animais modelo experimentais é essencial para a investigação médica comparativa. Nosso estudo teve como objetivo estabelecer parâmetros eletrocardiográficos e valores de referência para saguis-de-tufo-preto (Callithrix penicillata). Dezenove saguis-de-tufo-preto adultos saudáveis foram utilizados. Uma combinação de tiletamina e zolazepam foi empregada para contenção química antes da realização do exame eletrocardiográfico (ECG Knowledge of cardiac parameters in experimental animal models is essential for comparative medical research. Our study aimed to establish electrocardiographic parameters and reference values for marmosets (Callithrix penicillata). Nineteen healthy adult marmosets were used. A combination of tiletamine and zolazepam was used for chemical restrained before performing electrocardiography (ECG). A computerized ECG machine was used. Values of the ECG parameters were a mean heart rate of 264±74 beats/min, a variation MCA between 60° and -90°, a mean P wave duration of 34±6ms and amplitude of 0.132±0.051mV, a mean PR interval duration of 56±11ms, a mean QRS complex duration of 35±7ms and amplitude of 0.273±0.269mV, a mean QT interval duration 130±26ms, ST segment was isoelectric (13 animals) and with elevation (six animals) and a mean T wave amplitude of 0.19±0.083mV and positive. There was no significant difference between males and females. Thus, the electrocardiographic parameters obtained in our study in marmosets can be used as a reference values to in other future researches, providing researchers electrocardiographic parameters that contribute with the literature.INDEX TERMS: Primate, marmoset, Callithrix penicillata, cardiology, electrocardiography.

Electrocardiographic parameters of Sapajus libidinosus (SPIX, 1823) after chemical immobilization with tiletamine‐zolazepam

“…The mean value found in this study (82 ms in S libidinosus ) for the PR interval was very close to that described in other research on primates, that ranges from 70 ms for rhesus monkeys, to 80 ms for cynomolgus monkeys, Macaca arctoides and Japanese monkeys, with a bigger variation for interval duration of 120‐200 ms in humans, and 56 ms in the black‐tufted marmoset . The time that the electrical impulse takes to cross the atria and the atrioventricular node is represented by this interval, that is measured from the start of the P wave to the first deflection of the QR S complex…”

“…The T wave polarity was positive in all the animals, similar to that found in humans and black‐tufted marmosets . T wave inversion or other alterations in this morphology were not observed in the present research, different from reports by other authors in Japanese monkeys .…”

“…The mean QT interval was 164 ms in the present study. Variation has been reported for other primates of 200 ms in cynomolgus monkeys and Japanese monkeys, 270 ms in M arctoides, 130 ms in black‐tufted marmosets, and 170 ms in S apella, that belong to the same genus under study. The period between the start of ventricular depolarization and the end of repolarization is represented by this interval .…”

“…Several electrocardiographic studies have been carried out in various non‐human primate species but nevertheless there are no electrocardiographic studies on S libidinosus .…”

“…The P wave represents atrium activation and is generated by the start of the electric impulse in the sinoatrial node, followed by its rapid transmission through the atrium . Measurements of time and amplitude are indicative of left atrial overload (duration in ms) and right atrium (voltage in mV), but for the correct assertion that overloads would be necessary to perform chest X‐rays and/or echocardiogram, taking into account in view of the fact that tiletamine‐zolazepam, due to sympathomimetic action, would determine a reduction in the time of atrial depolarization by intensifying the electrical conductance in the cardiac tissue and not causing a delay. In this case, these animals may be carriers of some cardiomyopathy or simply these values may be considered as borderline for the species.…”