Atrial Septal Defect

Atrial septal defect (ASD) is an abnormality of the upper chambers of the heart (atria) where the wall between the right and left atria does not close completely. This defect is present at birth (congenital). In humans, when the person has no other congenital defect, symptoms may be absent, particularly in children. Symptoms usually have manifested by age 30. Individuals with ASD are at an increased risk for developing a number of complications including: Infective endocarditis, Heart failure, atrial fibrillation and stroke. ASD may not require treatment if there are few or no symptoms, or if the defect is small. Surgical closure of the defect is recommended if the atrial septal defect is large or if symptoms occur. With a small-to-moderate atrial septal defect, a person may live a normal life span without symptoms. Larger defects may cause disability by middle age because of increased blood flow and shunting of blood back into the pulmonary circulation.

Atrial Septal Defect in Pets

Atrial septal defect (ASD) is a common congenital heart disease (CHD) in humans, but considered relatively rare in veterinary medicine. However, modern echocardiographic and Doppler echocardiography currently offer a good view of the abnormalities facilitating earlier detection of ASD in awake animals. Boxer and Domestic shorthair cat are the most common canine and feline breeds affected. Most defects are without clinical signs. The most common clinical signs included heart murmur heard, exercise intolerance, fainting, difficulty breathing and cough.² In older dogs, ASD is sometimes found in addition to dilated cardiomyopathy. The long-term prognosis for dogs with isolated and small-sized ASD is usually good, but can be compromised by the presence of concurrent congenital or acquired cardiac diseases.³

References

1. Atrial septal defect, MedlinePlus
2. Chetboul V, Charles V, Nicolle A, Sampedrano CC, Gouni V, Pouchelon JL, Tissier R. Retrospective study of 156 atrial septal defects in dogs and cats (2001-2005). J Vet Med A Physiol Pathol Clin Med. 2006 May;53(4):179-84.
3. Guglielmini C, Diana A, Pietra M, Cipone M. Atrial septal defect in five dogs. J Small Anim Pract. 2002 Jul;43(7):317-22.