Chanoit G, Mathews KG, Keene BW, et al.
Case Description-A 6-year-old Siberian Husky-mix dog was examined for episodes of collapse. Clinical Findings-Physical examination, echocardiography, abdominal ultrasonography, ECG, and thoracic computed tomography with contrast were performed and revealed a 2.5 x 2.3 x 2.0-cm mass over the pulmonic valve leaflets, resulting in moderate pulmonic stenosis. Other abnormal findings included systemic hypertension, right bundle branch block, proteinuria, and a urinary bladder mass. Treatment and Outcome-Pulmonary arteriotomy was performed under inflow occlusion, and the mass was resected with transesophageal echocardiographic guidance and direct visualization. Results of histologic examination of the mass revealed a vascular hamartoma. Sequential follow-up examinations and telephone contacts (at 0.5, 5, and 15 months after surgery) revealed that the patient had been free from episodes of collapse since surgery. No regrowth of the mass was noted on follow-up echocardiograms, and the pulmonic stenosis had resolved, although mild to moderate pulmonary insufficiency later developed. The bladder mass was excised 15 months after the first surgery when hematuria developed, and results of histologic examination of this mass revealed a vascular hamartoma. The dog was eventually euthanized 31 months after the initial surgery for reasons that could not be directly linked to any recurrence of the pulmonary artery mass. Clinical Relevance-Hamartomas are benign tumors that can be located in various tissues, including large arteries. Computed tomography was helpful in predicting the resectability of the intracardiac mass in this dog. Treatment with arteriotomy under inflow occlusion and mild hypothermia resulted in a favorable outcome.