Case Study

Left congestive heart failure and mitral prolapse in a 14 year old FS Tibetan Terrier

A 14-year-old spayed female Tibetan Terrier dog was presented with a history of progressive coughing and wheezing. A grade V/VI left-sided systolic murmur was ausculted on physical examination. Premature ventricular contractions were seen on an electrocardiogram. The patient was treated with enalapril, pimobendan, and aminophylline.

Sonographic Differential Diagnosis

Mitral valve prolapse and severe insufficiency causing left sided volume overload. Left sided congestive heart failure. Emerging pulmonary hypertension.

Image Interpretation

The echocardiogram demonstrated a prominent right heart with mild right ventricular hypertrophy and mild right atrial prominence. Moderate tricuspid insufficiency was noted, which is consistent with secondary pulmonary hypertension. Prolapse of the posterior leaflet was noted. The prominent right heart is due to excessive intrathoracic pressures caused by chronic respiratory disease or conformational issues. The left ventricle in this patient was volume overloaded with subnormal contractility for this type of pathology, which is indicative of emerging myocardial insufficiency. The images also showed prolapse and severe insufficiency of the mitral valve, with moderate to severe chronic left atrial enlargement. Transdiaphragmatic view of the heart revealed a pleural irregularity or “shower curtain” effect in the caudal lung, which is suspicious for pulmonary thromboembolic disease or other form of alveolar disease. However, this diseased lung did not appear to be located in an area typical for progressive pulmonary edema. Aspirin therapy is warranted for this condition.

DX

Left congestive heart failure secondary to mitral valve disease. Emerging pulmonary hypertension.

Outcome

Continuation of ace inhibitor therapy, an increased dose of Lasix with monitoring of renal values, pimobendan, aspirin, spironolactone, and eventual addition of sildenafil with monitoring of blood pressure and electrocardiography was recommended for this patient. A guarded prognosis was given due to the patient’s risk for sudden death.

Clinical Differential Diagnosis

Primary cardiac disease – mitral or tricuspid valve insufficiency, pulmonary edema secondary to mitral valve insufficiency, myocardial weakness secondary to mitral valve insufficiency. Primary pulmonary disease – bronchitis, neoplasia, allergic, fibrosis.