Pulmonary embolism with filling defect in main pulmonary artery on CTPA

A 55-year-old woman presents 14 days after right total hip replacement with sudden pleuritic right chest pain, dyspnea, hemoptysis, and presyncope. She has been ambulating poorly and missed her last dose of rivaroxaban thromboprophylaxis. Vitals: HR 128, BP 92/58 mmHg, RR 28, SpO2 88% on room air. Wells score is 6.5 (high probability) and D-dimer is 4800 ng/mL. CT pulmonary angiography (CTPA) demonstrates a central hypodense filling defect straddling the bifurcation of the main pulmonary artery as shown by the structure marked **B**, with extension into both lobar arteries. RV to LV diameter ratio is 1.4 with septal bowing, and troponin I is elevated at 0.42 ng/mL. What is the most appropriate immediate management for this intermediate-high risk pulmonary embolism?