Abstract
Background: Rupture of the chordae tendineae of the tricuspid valve is rare in dogs. We report the case of a dog with tricuspid valve chordal rupture secondary to pulmonary hypertension.
Case Description: A 7.7-kg, 13-year-old neutered male Pekingese on annual heartworm prevention presented with respiratory distress. The patient was diagnosed with pulmonary hypertension and medically managed. However, the patient re-presented 405 days post-diagnosis with dyspnea and an increased abdominal circumference. Transthoracic echocardiography showed ruptured chordae tendineae of the tricuspid valve and abdominal ultrasound identified significant ascites associated with worsening right congestive heart failure. The patient improved after drainage of ascitic fluid and additional medical treatment but was discharged with a poor prognosis.
Conclusion: Ruptured chordae tendineae of the tricuspid valve should be considered in patients with pulmonary hypertension.

Key words: Canine, Chordal rupture, Congestive heart failure, Pulmonary hypertension