A 58-year-old man with a 3-day history of left leg swelling and pain presents to the emergency department with acute-onset dyspnea, severe chest pain, and hypotension (SBP 78 mmHg). A CT pulmonary angiogram shows a large thrombus straddling the bifurcation of the main pulmonary artery and extending into both right and left main pulmonary arteries, as marked **A** in the diagram. The patient is in cardiogenic shock with altered mental status. Which of the following is the most appropriate immediate management?