Cardiac disorders in dogs infected with Babesia canis

The aim of this study was to assess cardiac disorders in dogs infected with B. canis. The study included 50 dogs with babesiosis and 20 healthy control animals. All the animals had haematological tests, ECG, echocardiography and serum troponin I and CK-MB levels checked. The haematology in the group of dogs with babesiosis confirmed thrombocytopaenia in 100% of dogs, decreased haematocrit in 52% and anaemia in 46%. The most common abnormalities in ECG and echocardiography in dogs infected with protozoa included: change in appearance and/or amplitude of the T-wave (34%), increased fractional shortening (24%), an increased sinus rhythm (14%) and heart axis deviation (10%). In 19 of the 50 dogs with babesiosis, the level of serum troponin I was elevated. In 2 dogs that died from babesiosis, the troponin level I was very high. The ECG confirmed sinus tachycardia and interpolated ventricular beat in these animals. In all dogs with babesiosis that were used in the study, the serum CK-MB was high or very high and was within limits of 23.17 U/L - 369.62 U/L. The highest kinase concentration (367.33 U/L and 369.62 U/L) was observed in dogs that died due to the disease. The presented results prove that cardiac changes are common in canine babesiosis, but that most changes are nonspecific and appear to have little clinical significance. Cardiovascular assessment should be based on the assessment of the level of troponin I and CK-MB in the serum of sick animals. High concentrations of these factors might be indicators of poor prognosis.