Percutaneous thrombectomy in patients with massive and very high-risk submassive acute pulmonary embolism

Objective: Examine FlowTriever thrombectomy feasibility in high-risk PE patients. Background: The FlowTriever thrombectomy system (Inari Medical, Irvine, CA) can reduce right ventricle (RV) strain in acute submassive pulmonary embolism (PE) patients. This technology has not been studied in higher risk PE patients. Methods: This multicenter retrospective analysis included patients treated with FlowTriever between 2017 and 2019 if they met at least one of the following: vasopressor dependence, PE induced respiratory failure, or decreased cardiac index (CI) measured by right heart catheterization. Results: Analysis included 34 patients: 18 massive, four intubated, 12 normotensive but with CI < 1.8. Average age was 56 and their median simplified PE severity index was 2. Patients had high bleeding risk, with 13 having recent surgery, six posttrauma, and four recent strokes. Six patients received cardiopulmonary resuscitation, and two received additional mechanical circulatory support. All patients had RV dilatation and elevated biomarkers. Clot removal was successful in 32/34 patients. CI improved from 2.0 +/- 0.1 L/min/m(2) before thrombectomy to 2.4 +/- 0.1 L/min/m(2) after (p = .01). The mean pulmonary artery pressure decreased from 33.2 +/- 1.6 mmHg to 25.0 +/- 1.5 mmHg (p = .01). The two patients-both with no or minimal thrombus removed-deteriorated during the procedure: one died and the other was successfully stabilized on ECMO. There were no other major complications. All other patients were alive at the time of data collection (mean follow-up of 205 days). Conclusion: Aspiration thrombectomy appears feasible in higher risk acute PE patients with immediate hemodynamic improvement and low in-hospital mortality.