Progressive Shortness of Breath in a Patient on Dasatinib
A 49-year-old man presents to the emergency department with a 2-month history of progressive shortness of breath, lower leg swelling, and fatigue. He has no history of cardiovascular disease. His only cardiac risk factor is hypertension, for which he is on ramipril 2.5 mg daily. His medical history is significant for Philadelphia chromosome positive acute lymphoblastic leukemia, for which he is on dasatinib. On physical exam, his jugular venous pressure is elevated, his blood pressure is 130/80, and his heart rate is 65 bpm. Heart auscultation reveals normal S1 andS2 and a systolic murmur at lower sternal border. Lung auscultation reveals decreased breath sounds in lower lung fields. Chest X-ray shows small bilateral pleural effusions. A transthoracic two-dimensional echocardiogram is performed that reveals normal left ventricular systolic function, an ejection fraction of 65%, global longitudinal strain of -23%, and grade 1 diastolic dysfunction. Right ventricle is upper limit of normal size with normal function and estimated right ventricular systolic pressure of 58 mmHg.
Which one of the following is the most appropriate next diagnostic approach?