Safety and Efficacy of Acute Pulmonary Embolism Treated via Large-Bore Aspiration Mechanical Thrombectomy Using the Inari FlowTriever Device.

Purpose: To report initial experience with safety and efficacy in the treatment of pulmonary embolism (PE) using the FlowTriever device.

Materials And Methods: A single-center retrospective study was performed in all patients with acute central PE treated using the FlowTriever device between March 2018 and March 2019. A total of 46 patients were identified (massive = 8; submassive = 38), all with right ventricular (RV) strain and 26% with thrombolytic contraindications. Technical success (according to SIR reporting guidelines) and clinical success (defined as mean pulmonary artery pressure intraprocedural improvement) are reported, as are major device and procedure-related complications within 30 days after discharge.

Results: Technical success was achieved in 100% of cases (n = 46). Average mean pulmonary artery pressure improved significantly from before to after the procedure for the total population (33.9 ± 8.9 mm Hg before, 27.0 ± 9.0 mm Hg after; P < .0001; 95% confidence interval [CI], 5.0-8.8), submassive cohort (34.7 ± 9.1 mm Hg before, 27.4 ± 9.2 mm Hg after; P < .0001; 95% CI, 5.2-9.5) and massive cohort (30.4 ± 6.9 mm Hg before, 25.4 ± 8.2 mm Hg after; P < .05; 95% CI:0.4-9.6). Intraprocedural reduction in mean pulmonary artery pressure was achieved in 88% (n = 37 of 42). A total of 100% of patients (n = 46 of 46) survived to hospital discharge. In total, 71% of patients (n = 27 of 38) experienced intraprocedural reduction in supplemental oxygen requirements. Two major adverse events (4.6%) included hemoptysis requiring intubation, and procedure-related blood loss requiring transfusion. No delayed procedure-related complications or deaths occurred within 30 days of hospital discharge.

Conclusions: Initial clinical experience using the FlowTriever to perform mechanical thrombectomy showed encouraging trends with respect to safety and efficacy for the treatment of acute central, massive, and submassive pulmonary embolism.