Shortness of Breath in a Patient With Chronic Myeloid Leukemia
A 35-year-old woman presents to the emergency department with shortness of breath and mild orthopnea of 2 weeks' duration. She has no known risk factors for cardiovascular disease and has no previous history of cardiovascular disease. Her medical history is significant for chronic myeloid leukemia in the past 2 years. She was started on dasatinib (second-generation BCR-ABL tyrosine kinase inhibitor) and has continued dasatinib since the diagnosis, and her chronic myeloid leukemia is well-controlled with undetectable disease. On initial examination, she was hemodynamically stable and without focal clinical findings, with the exception of decreased breath sounds at the left lung base. Her chest x-ray is shown in Figure 1.
Which one of the following conditions is the most likely cause of shortness of breath in this patient?