Obesity is one of the most frequently seen nutritional problems to happen in companion animals and can lead to severe healthy problems in dogs and cats, such as cardiovascular diseases. This research aimed at evaluating the structural and functional cardiac alterations after weight loss of obese dogs. For such, fifteen obese healthy dogs were assigned into three different groups, according with their body weight: I (dogs up to 15Kg), II (dogs weighing between 15,1 and 30Kg), and III (dogs weighing over 30Kg). Moreover, group IV was composed by adding all animals included in groups I to III (dogs weighing from 10 to 59,2Kg). The animals were submitted to a caloric restriction weight-loss program, whose target weight was defined as 15% below their admittance body weight. The echocardiogram and blood pressure evaluations were performed before the diet was started and upon reaching the target weight. Data showed a significant decrease in left ventricular free wall thickness in groups III (1,07±0,17cm to 0,84±0,24cm in diastole and 1,52±0,41cm to 1,23±0,30cm in systole, p<0,05) and IV (0,93±0,16cm to 0,80±0,15cm in diastole and 1,32±0,33cm to 1,14±0,27cm in systole, p<0,05), in systolic blood pressure in groups III (158±20mmHg to 144±11mmHg, p<0,05) and IV (145±15mmHg to 133±19mmHg, p<0,05), mean blood pressure in groups II (112±6mmHg to 92±13mmHg, p<0,05) and IV (107±13mmHg to 93±16mmHg, p<0,05), diastolic blood pressure in group IV (87±13mmHg to 73±16mmHg, p<0,05); and a significant increase in left atrium/aorta ratio in group I (1,10±0,12cm to 1,16±0,11cm, p<0,05), and in end-systolic left ventricular volume index in groups III (20,41±6,74ml/m² to 28,83±9,39ml/m², p<0,05) and IV (20,86±6,47ml/m² to 25,00±9,47ml/m², p<0,05). Furthermore, it wasn't observed significant alterations in left atrium and aorta diameters, left ventricular internal diameter, septal thickness, ejection fraction and shortening fraction. It was possible to conclude that the weight loss program reverted the structural cardiac alterations observed by echocardiogram and decreased the arterial blood pressure in obese dogs that were fed a hypocaloric diet.

References

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