Double-chambered right ventricle in two dogs

Area of Science:

• Veterinary Cardiology
• Congenital Heart Defects
• Canine Cardiovascular Surgery

Background:

• Double-chambered right ventricle (DRCV) is a rare congenital cardiac anomaly.
• This condition involves an anomalous muscular ridge dividing the right ventricle into two chambers, leading to outflow obstruction.

Observation:

• Selective angiocardiography identified DRCV in two young dogs.
• One dog presented with a significant pressure gradient (67 mm Hg) across the right ventricular outflow tract.
• The second dog had a clinically insignificant gradient, with bilateral cardiac enlargement noted later.

Findings:

• Surgical intervention for the dog with a significant gradient resulted in a complete recovery and normal clinical status 1.5 years post-operation.
• The absence of valvular abnormalities and pressure gradient at surgery confirmed a congenital muscular obstruction.
• The second dog remained asymptomatic with a normal electrocardiogram despite cardiac enlargement.

Implications:

• Surgical resection of the obstructing muscular band is an effective treatment for symptomatic DRCV in dogs.
• Conservative management may be appropriate for cases with minimal pressure gradients and no clinical signs.
• Early diagnosis and appropriate intervention can lead to excellent long-term outcomes for canine congenital heart disease.