A 42-year-old woman with no known medical illness presented to the ED with shortness of breath for the past 5 days, which acutely worsened a few hours ago. On physical examination, she was tachypneic, lethargic with altered mental status, normotensive but tachycardic, and had an oxygen saturation of 92% on room air. Lung auscultation revealed reduced breath sounds bilaterally, and heart auscultation showed no murmurs. Her chest X-ray was clear, but the ECG showed a typical S1 Q3 T3 pattern.

Her troponin T and D-dimer levels were both significantly elevated, at 289 pg/mL (normal < 14) and 3195 ng/mL, respectively. An ECHO revealed signs of right ventricular (RV) overload and dysfunction. Given the high clinical suspicion for pulmonary embolism, she was sent for a CT pulmonary angiogram, which confirmed a massive bilateral pulmonary embolism (PE). She was classified as Class V on the Pulmonary Embolism Severity Index (PESI) and diagnosed with intermediate-high risk PE.

Given the clinical severity and high risk of progressive hemodynamic deterioration leading to decompensated shock, the invasive catheterization lab was activated for emergency percutaneous catheter-directed mechanical thrombectomy.

Right femoral vein access was obtained under ultrasound and fluoroscopy guidance. A 6Fr multipurpose (MP) catheter was used to deliver a J-tip guidewire into the main pulmonary artery, which was then exchanged for a pigtail catheter. Digital subtraction angiography revealed filling defects in the truncus anterior and bilateral interlobar arteries. The 6Fr femoral sheath was upsized to a 16Fr sheath. The Penumbra ENGINE and Lightning Flash 2.0 system, with a 16Fr aspiration catheter, was primed. Using the MP catheter, the J-tip guidewire was delivered into the left pulmonary artery and exchanged for the 16Fr aspiration catheter. Multiple aspiration runs were performed using the computer-assisted vacuum thrombectomy system. The same steps were repeated for the right pulmonary artery. The procedure lasted 2 hours, with 1.2L of blood loss and approximately 6-8 cubic centimeters of fresh clots aspirated. The patient received 2 units of packed red blood cells during the procedure. Femoral access was closed with a figure-of-8 suture.

The patient was transferred to the Cardiac Care Unit for close monitoring and continued on parenteral anticoagulation. Less than 12 hours post-procedure, she showed remarkable clinical improvement. Her altered mental status, tachycardia, and tachypnea resolved, and oxygen saturation improved to 99% on room air. A repeat ECHO showed improvement in RV function, with a TAPSE of 1.35 cm and an S' 9.0 cm/s. She was discharged well 5 days later. Intermediate to high risk PE remains a disease with sub-optimal clinical outcomes. Early mechanical thrombectomy should be considered for rapidly deteriorating patients, even in the absence of hemodynamic instability.