Double chambered right ventricle in 9 cats.

Area of Science:

• Veterinary Cardiology
• Congenital Heart Defects
• Feline Medicine

Background:

• Double-chambered right ventricle (DCRV) is a known congenital cardiac anomaly in humans and has been reported sporadically in dogs and cats.
• A comprehensive description of the clinical and echocardiographic features of DCRV in cats is lacking in veterinary literature.

Purpose of the Study:

• To systematically describe the clinical and echocardiographic features of DCRV in a cohort of cats.
• To assess the prevalence and clinical significance of DCRV in feline patients.

Main Methods:

• Retrospective case series of nine cats diagnosed with DCRV.
• Echocardiographic evaluation including measurements of pressure gradients and assessment of concurrent cardiac abnormalities.
• Clinical data including signalment, presenting signs, and long-term outcomes were collected.

Main Results:

• Nine cats aged 4 months to 10 years presented with DCRV.
• Echocardiography revealed obstructive fibromuscular bundles dividing the right ventricle, with marked proximal hypertrophy and common right atrial dilation.
• A significant mean pressure gradient of 130 ± 50 mm Hg was measured across the obstruction. Concurrent defects included VSD, aortic abnormalities, and peritoneo-pericardial diaphragmatic hernia.
• Five cats remained asymptomatic long-term, while three developed congestive heart failure. One cat died during surgical intervention.

Conclusions:

• Double-chambered right ventricle (DCRV) is a congenital cardiac abnormality that may be more common in cats than previously recognized.
• Echocardiography is crucial for diagnosing DCRV and assessing its severity and associated complications in cats.