Hypothyroidism which is one of the generally encountered endocrin diseases in dogs, that effects skin, nerves, urinary system, gastro-intestinal system, reproductive system, musculoskeletal system and eye and beside makes serious defects in the cardio-vase ular system. In this case, which we diagnosed as primary hypothyroidism via clinical symptoms and laboratuary tests (K<-4) in a 8 aged male Shetland breed sheepdog cardio-vascular system disturbances were determined by electrocardiographic and echocardiographic methods.
As the result of the electrocardiographic measurements, while the heart rate was 120 beat/minute, rhythm disturbances such as sino-atrial block was observed. It was determined that electrocardiographic wave amplitudes were decreased (P amplitude < 0.2 mV and R amplitude <1.5 mV), but there were no morphological abnormalites. In the echocardiographic examinations, right ventricular and intraventricular septal hypokinesia were observed. Decreased left ventricular systolic-diastolic with left atrium diameter and left ventricular fractional shortening (FS %26) were observed. Left ventricular posterior wall and aort diameters were in normal limits.