Safety and Clinical Outcomes of Aspiration Thrombectomy in Patients with Intermediate-High Risk PE: A Single-Center Retrospective Review

This preliminary study seeks to evaluate safety and clinical outcomes for patients with acute intermediate-high risk pulmonary embolism (PE) following aspiration thrombectomy. We hope to add to the growing body of work surrounding this patient population with inclusion of more long-term outcomes.


Materials and Methods:

This IRB approved single-arm retrospective review was performed on patients with intermediate-high risk PE undergoing aspiration thrombectomy from Jan. 2015 to Dec. 2021. An internal database was queried for PE thrombectomy procedures, and electronic health records reviewed for selected periprocedural clinical values, procedural reports and images, and post procedural follow up. Patients were excluded if they had previously failed a course of systemic thrombolysis or if surgical embolectomy was performed, to avoid confounding our assessment of relevant interventions. Primary outcomes were 30-day and one-year mortality, procedure-related complications, and technical success as defined by sufficient removal of thrombus without repeat intervention within 30 days.



Results:

60 patients with intermediate-high risk PE were treated with large-bore suction thrombectomy. Baseline CTs were obtained in 59 patients, with average RV/LV ratio (1.66 +/- 0.48; n = 56) and mean PA diameter (32.14 +/- 4.40; n = 59) serving as measures of PE severity. 5 patients (8.3%) required adjunctive catheter-directed lytic therapy (CDT), with a mean tPA dose of 20.4mg (range of 8 to 50mg). Technical success was achieved in 97% of cases. Complication rate was 3%, with 1 occurrence of insufficient clot retrieval and 1 self-resolved episode of hemodynamic instability. PE recurrence occurred in 1 patient within a year of intervention. 30-day mortality was 1.7%, with 1 patient transitioning to comfort care following basilar artery occlusion. One year mortality was 16% (9/56), with 7 of the additional deaths attributable to advanced cancer and 1 to unrelated systemic infection. Of note, 4 patients were still within a year of intervention, with no mortality at 10+ months. Patients requiring adjunct CDT had a 0% complication and 30-day mortality rate.



Conclusion:

This single-arm retrospective review found high technical success in patients with intermediate-high risk PE. 30-day procedure-related mortality and severe adverse event rates were 0%, further supporting that large-bore aspiration thrombectomy could provide a safe and effective first-line treatment. One year mortality related to PE was 0%, suggesting the possibility of sustained mortality benefit, although further studies are needed.