Can a dog have a heart attack, especially if it is a small breed? Unfortunately, yes. Nearly all small breeds are prone to heart failure. The Pomeranian, in particular, suffers from patent ductus arteriosus. Luckily, this defect can be fixed by the means of surgery.
Gentle, friendly and devoted, the Collie is another breed exposed to the heart problems. It, too, has issues with patent ductus arteriosus. The symptoms primarily include the bluish-grey shade of gums as the blood does not receive sufficient oxygen.
This intelligent and docile breed is subject to having ventricular septal defects. These occur when there is a gap between the ventricles. As a result, too much blood can be redirected to the lungs, which leads to the congestive heart failure in dogs of this breed.