Q. A 58-year-old male presents to the emergency department complaining of chest pain that began suddenly and has been ongoing for the last 30 minutes. The patient reports that the pain is located in the center of his chest and is described as a crushing sensation. He also reports shortness of breath, nausea, and diaphoresis. The patient has a history of hypertension, hyperlipidemia and a past myocardial infarction. He is currently taking aspirin, atorvastatin, lisinopril, and metoprolol. On physical examination, the patient is alert and oriented but appears uncomfortable. His blood pressure is 160/90 mm Hg, heart rate 110/min, respiratory rate 20/min, and oxygen saturation is 96 percent on room air. The patient's cardiac examination reveals tachycardia and the presence of a III/VI systolic murmur. You order an electrocardiogram which shows ST-segment elevation in leads II, III, and aVF, consistent with an acute myocardial infarction. Laboratory results show an elevated troponin level. You order the patient to be given morphine, nitroglycerin, and aspirin, and place him on oxygen via facemask and cardiac telemetry. Suddenly, the patient becomes unresponsive and you note acute changes in his cardiac telemetry (see image). Which of the following interventions is the best next step in managing this patient?