Congenital Heart Disease
Congenital heart disease is present at birth, and there are a variety of conditions that fall into this category.
Patent Ductus Arteriosus
Patent ductus arteriosus (PDA) is a common heart defect that is present at birth. The ductus arteriosus is a short blood vessel that normally allows blood to bypass the lungs, which are nonfunctional in an unborn dog. The ductus closes shortly after birth, but when it remains open, the blood leaks back into the other side of the heart. The heart must pump more blood to maintain a normal blood flow. PDA is detected by a continuous heart murmur.
Certain breeds, including the Miniature Poodle, German Shepherd, and Cocker Spaniel, are more prone to the condition. It is also more common in females than males. The signs of PDA include the following:
Collapse
Coughing
Exercise intolerance
Heart murmur
Labored breathing
Seizures
Fainting spells
Heart failure ultimately results and surgery is required as early as possible to close the patent ductus.
Pulmonic Stenosis
Smaller dogs are more prone to pulmonic stenosis. This common congenital heart defect is the third most common canine congenital heart defect. Pulmonic stenosis is a narrowing of the right ventricle and the pulmonary artery of the heart. The narrowing causes an overload in the right ventricle and ultimately produces thickening of the heart muscle.
A revolutionary new method of treating PDA is interventional catheterization. Catheters are used to close the PDA. The surgeon inserts a stainless steel fiber–embedded coil into a catheter to close off the hole. This procedure is less invasive than traditional surgery and the recovery time for the dog is minimal. However, not all dogs are suitable for this type of closure.
Severe cases of pulmonic stenosis require treatment. Valvuloplasty is more successful if conducted early before extensive remodeling of the heart has occurred. In this procedure, a catheter with a balloon is inserted into the heart through a blood vessel. The balloon is inflated to widen the steno-sis. Balloon valvuloplasty is less invasive for the dog than traditional surgery and is 70 percent more successful.
