Pericardial Effusion in Cats: a Retrospective Study of Clinical Findings and Outcome in 146 Cats

Background: Pericardial effusion (PE) in dogs most often is associated with neoplasia or idiopathic pericarditis, and frequently causes cardiac tamponade. Studies of PE in the cat are limited.

Hypothesis: Congestive heart failure (CHF) is the most common cause of PE in the cat.

Animals: All cats diagnosed with PE on echocardiographic examination at the Matthew J. Ryan Veterinary Hospital of the University of Pennsylvania (MJR-VHUP) from 2000 to 2005.

Methods: The clinical and pathologic findings in 146 cats with PE were reviewed. Records were examined retrospectively to identify additional underlying conditions. Follow-up status and cause of death were determined by review of the medical records or phone interviews with the owners.

Results: The most common cause of PE in this study was CHF (75%). Biochemical abnormalities were uncommon, but aspartate aminotransferase (AST) activity frequently was increased (85%). Follow-up information was available on 108 cats (74%). Median survival time (MST) was 144 days for cats that were not euthanized within 24 hours (n = 85). The MST of cats with heart failure was 41 days, whereas the MST of cats without heart failure was 361 days, when those euthanized within 24 hours were excluded.

Conclusions: Survival time of cats with heart failure in this study was significantly shorter than previously reported, and significantly shorter than in cats without heart failure as a cause of PE.