@ARTICLE{Mazurek_Ł._Cardiovascular_2024,
 author={Mazurek, Ł. and Staniec, M. and Żółkiewski, P. and Skrzypczak, M. and Adaszek, Ł.},
 volume={vol. 27},
 number={No 4},
 pages={501–511},
 journal={Polish Journal of Veterinary Sciences},
 howpublished={online},
 year={2024},
 publisher={Polish Academy of Sciences Committee of Veterinary Sciences},
 publisher={University of Warmia and Mazury in Olsztyn},
 abstract={The effects of T4 are mainly manifested by positive ino- and chronotropism. The syndrome accompanying hypothyroidism in rabbits (impaired myocardial contractility and reduced ejection capacity) is caused by a deficiency of thyroid hormones - especially T4. The study group consisted of a total of 41 animals: 15 males and 26 females, ranging in age from 2 months to 8 years. with echocardiogram showing reduced fractional shortening (<30%), with normal results of heamatological and biochemical tests. Blood was collected in order to measure T4 level. Echocardiographic examinations were performed with two-dimensional (2D) imaging, M-mode measurements and the pulsed/colour-labelled Doppler technique. Statistical analysis was performed using Statistica 13.0. Correlations were determined: between serum thyroxine concentration and the value of the fraction of shortening in the groups: young animals (up to 5 years of age) and older animals, females and males, and sterilised and non-sterilised animals. Statistical analysis showed a positive correlation between T4 levels in the blood of the test animals and myocardial fractional shortening and heart rate and left-atrial to aortic ratio (LA/Ao) in the pre-treatment period. A positive correlation was also shown after dividing the patients into 2 groups based on their age (below 5 years vs. 5 years and over), sex (male and female rabbits) and fact of sterilization (yes/no). Our study unequivocally confirmed a positive correlation between the decreased serum T4 concentration and reduced fractional shortening, indicating decreased cardiac systolic function in hypothyroid rabbits.},
 title={Cardiovascular problems in rabbits in reference to hypothyroidism – a four-year retrospective study},
 type={Article},
 URL={http://czasopisma.pan.pl/Content/133628/PDF/2%20_%20Mazurek.pdf},
 doi={10.24425/pjvs.2024.151745},
 keywords={rabbit, hypothyroidism, echocardiographic examination, levothyroxine},
}