• TVD is a congenital defect of the tricuspid valve and its related structures (ie papillary muscles and chordae tendineae).
• It is an uncommon congenital heart disease in dogs, accounting for 2% of all congenital conditions in one study. TVD is most often detected in large breed dogs, and in particular, the Labrador Retriever Retriever: Labrador. TVD is occasionally seen in cats.
• TVD causes tricuspid regurgitation, right heart enlargement, and in severe cases, right heart failure.
• Signs: asymptomatic murmur in many cases and animals can remain asymptomatic for years. In more severe cases right sided heart failure may develop and then common clinical signs include abdominal distension, jugular pulsation, weakness, and poor appetite. 
• Treatment: involves standard medical therapy for heart failure.
• Prognosis: poor in severely affected animals.

Presenting signs

• Asymptomatic.

• Weakness.
• Lethargy.
• Poor appetite.
• Abdominal swelling/distension.

• Syncopal episodes (poor cardiac output secondary to, eg arrhythmia Heart: dysrhythmia and/or congestive heart failure Heart: congestive heart failure ).

Acute presentation

• In severely affected animals, signs of right heart failure usually predominate, including:
  • Ascites.
  • Jugular venous distension and positive hepato-jugular reflex.
  • Pleural effusion (less common than ascites).
  • Weakness.
  • Poor appetite.
  • Labored breathing due to compromise of thoracic space (due to ascites).
• While, this acute presentation is occasionally seen in young animals, many with TVD remain asymptomatic for many years.

Age predisposition

• A heart murmur Murmur: overview is first detected in young puppies and kittens that are often asymptomatic; risk of clinical signs increases as animal ages, many animals remain asymptomatic for years.

Breed/Species predisposition

• In dogs, TVD is most commonly diagnosed in Labrador retrievers Retriever: Labrador. Veterinary database studies also suggest that German Shepherds German Shepherd Dog are at increased risk. The  Dougue de Bordeaux Dougue de Bordeaux is also thought to have an inherited form of TVD. TVD is usually seen in large breed dogs.

Cost considerations

• Treatment costs equivalent to any other case of congestive heart failure (standard therapy).

Special risks

• Patients with decompensated heart failure are often very poor anesthetic candidates and every attempt should be performed to avoid anesthesia Anesthesia: for cardiovascular insufficiency.