A 27-year-old female with a history of congenital heart disease (CHD) presents with persistent fever for 2 weeks. On admission: anemic appearance, grade 4/6 harsh systolic murmur with thrill at left sternal border (3rd-4th intercostal space), spleen 2 cm below the costal margin, and two positive blood cultures. On day 3, she suddenly develops dyspnea, chest pain, and recurrent hemoptysis. The most likely diagnosis is: