Soru

Progressive dyspnea and persistent chills over the past week prompt the hospitalization of a $34$-year-old woman with a well-documented history of injection drug use. Initial blood cultures are drawn, and she is started on empiric intravenous vancomycin and cefepime. On the second day of admission, the nursing staff calls for urgent evaluation due to a sudden decline in her mental status. Vital signs show a temperature of $38.8^\circ C$ ($101.8^\circ F$), blood pressure of $72/40$ mmHg, heart rate of $134$/min, and respiratory rate of $28$/min. Her extremities are cool with thread-like peripheral pulses. Cardiac auscultation reveals tachycardia with a soft first heart sound ($S_1$), a prominent third heart sound ($S_3$), and a short, early diastolic decrescendo murmur best heard along the left sternal border. Lung auscultation demonstrates bilateral crackles extending to the mid-lung fields along with scattered expiratory wheezes. A bedside echocardiogram reveals a $1.6$-cm highly mobile echodensity attached to the aortic valve, accompanied by severe leaflet destruction and massive retrograde flow into a normal-sized left ventricle. Which of the following is the most appropriate next step in the management of this patient?