UMEM Educational Pearls

Title: Management of Submassive Pulmonary Embolism

Category: Critical Care

Keywords: Pulmonary Embolism, PE, submassive PE, thrombolysis, catheter-directed thromblysis, thrombectomy, echo (PubMed Search)

Posted: 1/19/2016 by Daniel Haase, MD (Updated: 2/10/2016)
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What classifies "submassive PE"?

  • Echocardiographic signs of RV strain (RV dilation/systolic dyfunction, decreased TAPSE)
  • Hemodynamic stability (SBP >90)
  • Patients may or may not have abnormal cardiac biomarkers (elevated troponin, BNP)

Submassive PE has early benefit from systemic thrombolysis at the cost of increased bleeding [1].

Ultrasound-accelerated, catheter-directed thrombolysis (USAT) [the EKOS catheters] has been shown to be safe, with low mortality and bleeding risk, as well as immediately improved RV dilation and clot burden [2-4]. USAT may improve pulmonary hypertension [4].

USAT is superior to heparin/anti-coagulation alone for submassive PE at reversing RV dilation at 24 hours without increased bleeding risk [5].

Long-term studies evaluating chronic thromboembolic pulmonary hypertension (CTEPH) need to be done, comparing USAT with systemic thrombolysis and surgical thombectomy.

Take-home: In patients with submassive PE, USAT should be considered over systemic thombolysis or anti-coagulation alone.

References

1. PEITHO Investigators. Fibrinolysis for patients with intermediate-risk pulmonary embolism. N Engl J Med. 2014 Apr 10;370(15):1402-11.

2. Engelhardt TC, Taylor AJ, et al. Catheter-directed ultrasound-accelerated thrombolysis for the treatment of acute pulmonary embolism. Thromb Res. 2011 Aug;128(2):149-54

3. Bagla S, Smirniotopoulos JB, et al. Ultrasound-accelerated catheter-directed thrombolysis for acute submassive pulmonary embolism. J Vasc Interv Radiol. 2015 Jul;26(7):1001-6.

4. SEATTLE II Investigators. A Prospective, Single-Arm, Multicenter Trial of Ultrasound-Facilitated, Catheter-Directed, Low-Dose Fibrinolysis for Acute Massive and Submassive Pulmonary Embolism: The SEATTLE II Study. JACC Cardiovasc Interv. 2015 Aug 24;8(10):1382-92.

5. Kucher N, Boekstegers P,et al. Randomized, controlled trial of ultrasound-assisted catheter-directed thrombolysis for acute intermediate-risk pulmonary embolism. Circulation. 2014 Jan 28;129(4):479-86.