Review Question - QID 214209

A 67-year-old man presents to the emergency department with fatigue, malaise, and a 33-pound weight loss over the past 2 months. He finally came into the ED when his son came home to visit and thought he looked ill. The patient states that he has felt weak, fatigued, and has had little appetite. The patient has a past medical history of obesity, diabetes, smoking, and alcoholism and is notably noncompliant with his medications. He has recently been visiting one of his nephews in prison. His temperature is 97.0°F (36.1°C), blood pressure is 157/88 mmHg, pulse is 84/min, respirations are 16/min, and oxygen saturation is 94% on room air. Physical exam is notable for temporal wasting and a frail-looking man. There is yellowing of the patient's sclera and skin. His abdomen is nontender, and rectal exam reveals no occult blood. The patient becomes hypotensive so a central line is placed, and he is started on IV antibiotics and vasopressors. The patient is admitted to the hospital, and on day 1 he becomes pulseless on the hospital floor. CPR is initiated; however, the patient ultimately is pronounced dead. Post-mortem analysis reveals a pulmonary embolism and multiple thrombi and vegetations on the aortic and pulmonary valve. These are found to be platelet thrombi with fibrin and without any organisms or neutrophils. Which of the following is the most likely diagnosis?