Patent ductus arteriosus in cats (Felis catus): 50 cases (2000-2015).

OBJECTIVES: To describe signalment, clinical characteristics, diagnostic, treatment, and outcome data in a large case series of cats with patent ductus arteriosus (PDA).

ANIMALS: Fifty cats with confirmed PDA.

METHODS: Retrospective review of medical records from five referral veterinary hospitals for cats with PDA between 2000 and 2015. Cats were included if a PDA was visualized echocardiographically, during surgery, or on post-mortem examination.

RESULTS: Median age at presentation was 6 months (range: 36 days-9.7 years; n = 50), and sex distribution was approximately equal (27 male, 23 female). Most cats did not have clinical signs (70.2%; 33/47) at the time of presentation. Murmurs were classified as continuous (55%; 22/40) or systolic (45%; 18/40). Echocardiography confirmed left-to-right shunting in 33 cats (82.5%; 33/40) and right-to-left shunting in 7 (17.5%; 7/40). Concurrent cardiac anomalies were identified in 54.5% (18/33) and pulmonary hypertension in 45.7% (16/35). Closure was pursued in 68% (34/50), and complications associated with the procedure occurred in 14.7% (5/34) of cats, including one intraoperative mortality. Long-term follow up was available in 80% (40/50) of cats.

CONCLUSIONS: Cats with PDA often do not display clinical signs and may not have the characteristic physical examination findings typical of PDA in dogs. An increased prevalence of concurrent cardiac anomalies and pulmonary hypertension were found relative to previous reports. Thoracic radiographs and echocardiogram may provide the most comprehensive information for making a diagnosis and treatment recommendations. PDA closure was associated with a favorable long-term outcome in cats included in this study.