Echocardiographic and clinicopathologic characterization of pericardial effusion in dogs: 107 cases (1985-2006)

Objective-To evaluate sensitivity and specificity of echocardiography for diagnosis of cardiac masses in dogs with pericardial effusion. Design-Retrospective case series. Animals-107 dogs with pericardial effusion. Procedures-Records of dogs with pericardial effusion examined at the University of California-Davis Veterinary Medical Teaching Hospital from 1985 to 2006 were reviewed. Dogs were included when echocardiography and pericardectomy or necropsy were performed. Sensitivity, specificity, and metastatic rates were calculated for various causes of pericardial effusion. Results-107 dogs with pericardial effusion were evaluated by surgery (n = 48 dogs), necropsy (44), or both (15). Echocardiography revealed no mass (n = 41 dogs), a right atrial (RA) mass (38), a heart base (HB) mass (23), a pericardial mass (2), an HB and an RA mass (2), and a right ventricular mass (1). Sensitivity and specificity were 82% and 100%, respectively, for detection of a cardiac mass; 82% and 99%, respectively, for detection of an RA mass; and 74% and 98%, respectively, for detection of an HB mass. Most HB masses were neuroendocrine or ectopic thyroid gland tissue, but 3 were hemangiosarcomas and 4 were mesotheliomas. Most RA masses were hemangiosarcomas, but this group also included a neuroendocrine tumor, ectopic thyroid gland tissue, mesothelioma, lymphosarcoma, and sarcoma. Metastatic rates did not differ (50% to 66%) among neoplastic causes. Conclusions and Clinical Relevance-Echocardiography had high sensitivity and specificity for diagnosis and differentiation of RA or HB masses in dogs with pericardial effusion. There was a high rate of metastasis for cardiac masses of all causes. (J Am Vet Med Assoc 2009;235:1456-1461)