A six year old German Shepherd presents to you for a sudden onset of marked lethargy and exercise intolerance. On physical examination the heart sounds are muffled and the femoral arterial pulses are very weak. Thoracic radiographs reveal marked cardiomegaly and no pleural effusion. There is no evidence for pulmonary edema. The EKG reveals low amplitude QRS complexes.
Does the very enlarged heart represent heart failure, if so what is the cause?
The Two-dimensional Echocardiogram reveals a marked pericardial effusion. A thorough examination of the region of the right atrium indicates a mass attached to the outside wall. Although M-mode Echocardiography is ideal to assess the contractility of the left ventricle, in the presence of the pericardial effusion such assessments are erroneous.
Some ultrasonographs enable the technician to perform ultrasound assisted biopsies. Thus a sample of the effusion can be obtained for analysis and culture with the assistance of ultrasound to guide the placement of the biopsy needle.
Doppler Echocardiography has no real value in this type of case.