A 53-Year-Old With Progressive Dyspnea

CASE PRESENTATION: A 53-year-old woman with a history of pulmonary embolism treated with rivaroxaban came to the ED after 4 days of acutely worsening dyspnea and chest pressure. On arrival, her temperature was 36.7 degrees C; heart rate, 71 beats/min; BP, 98/ 59 mm Hg; respiratory rate, 22 breaths/min; and SpO2 95% on room air. Her WBC count was elevated at 15,770/mL; hemoglobin, 13.3 g/dL; platelets, 280,000/mL; INR (international normalized ratio), elevated at 1.66; and partial thromboplastin time, elevated at 18.8 s. Serum chemistry results were unremarkable, and pro-brain natriuretic peptide was slightly elevated at 530 pg/mL (normal, < 300 pg/mL).