Eisenmenger's syndrome in a domestic shorthair cat with bilateral abdominal cryptorchidism

An eleven-month-old, male domestic shorthair cat was presented for neutering. The cat was bright, alert and responsive, with a good body condition. During the clinical examination, no testicles were palpable in either the scrotum or the inguinal region. Thoracic auscultation revealed a grade 3/6 systolic left-sided heart base murmur. Upon further investigation, a stress-induced cyanosis was apparent. Echocardiography revealed right ventricular hypertrophy, a ventricular septal defect (VSD) with right-to-left shunting, dextroposition of the aorta, and pulmonary hypertension. A diagnosis of VSD with Eisenmenger's syndrome was determined. The patient was then treated with atenolol. Afterwards, both testicles were removed during an exploratory laparotomy. Six months after surgery, the cat demonstrated a good body condition, though it continued to be exercise intolerant.