A 37-year-old man with a known history of an atrial septal defect was admitted to the hospital with shortness of breath, hemoptysis, chest pain, and tightness. On admission, the patient had a heart rate of 120 beats/min, respiratory rate of 21 breaths/min, basal resting oxygen saturation of 81%, and blood pressure of 99/60 mmHg. Transthoracic echocardiography showed the presence of a secundum type of atrial septal defect with a diameter of 21 mm, right ventricular (RV) enlargement,