Review Question - QID 109789

A 65-year-old man presents to the emergency department for sudden weakness. He was at home enjoying his morning coffee when his symptoms began. His left arm suddenly felt very odd and weak thus prompting him to come to the ED. The patient has a medical history of diabetes, COPD, hypertension, anxiety, alcohol abuse, and PTSD. He hs no recent history of trauma. He typically drinks 5-7 drinks per day and his last drink was yesterday afternoon. His current medications include insulin, metformin, atorvastatin, lisinopril, albuterol, and fluoxetine. His temperature is 99.5°F (37.5°C), blood pressure is 177/118 mmHg, pulse is 120/min, respirations are 18/min, and oxygen saturation is 93% on room air. On physical exam, the patient is mildly confused. Cardiopulmonary exam demonstrates bilateral expiratory wheezes and a systolic murmur along the right upper sternal border that radiates to the carotids. Neurological exam reveals cranial nerves II-XII as grossly intact with finger-nose exam mildly abnormal on the left and heel-shin exam within normal limits. The patient has 5/5 strength in his right arm and 3/5 strength in his left arm. The patient struggles to manipulate objects such as a pen with his left hand. The patient is given a dose of diazepam and started on IV fluids. Which of the following is the most likely diagnosis in this patient?