This case involves an 8-month-old male neutered mixed breed dog who was presented to Cornell’s Small Animal Emergency Service on 9/13/19 for a one week history of labored breathing and marked ascites. On presentation, the patient was cachexic with marked abdominal distension. Abdominocentesis was performed and the client opted outpatient care with the plan to return to Cornell for a cardiology consult on 9/16/19 since the patient was considered stable. The patient was adopted from a shelter in South Carolina and was diagnosed with a grade 2/6 heart murmur earlier in the summer. Since the time of adoption, the patient began showing signs of exercise intolerance, lethargy and failure to thrive. In August 2019, the patient was taken to his referring veterinarian where he was diagnosed with a grade 5/6 murmur and marked ascites. The patient was placed on a loop diuretic (furosemide) and then referred to a cardiologist two days later where he was diagnosed with pulmonic stenosis and right sided heart failure. The treatment protocol was amended to include a beta-blocker (atenolol) as well as an increase in the dose of furosemide. Plans for balloon valvuloplasty were discussed, however, the patient’s condition progressed rapidly before the surgical procedure could be performed. On presentation to Cornell’s Cardiology Service on 9/16/19, evidence of marked ascites was assessed, along with a grade 5/6 left basilar systolic murmur. Echocardiogram revealed severe tricuspid regurgitation, marked right ventricular hypertrophy, severe right atrial dilatation, evidence of intermediate type pulmonic stenosis (type A and type B) as well as a pulmonic gradient of 165 mmHg. The referring cardiologist noted a pulmonic gradient of 132 mmHg which suggested, along with the other compelling cardiac changes and associated clinical signs, that the patient’s condition was life threatening. Discussions with the owner regarding right sided heart failure, balloon valvuloplasty and prognosis resulted in the procedure being successfully performed later that week. The patient is currently being treated for right sided heart failure and is still undergoing serial abdominocentesis.