Phenotype-directed use of large-bore mechanical thrombectomy in high-risk pulmonary embolism: a retrospective case...

High-risk pulmonary embolism (PE) carries substantial mortality. Systemic thrombolysis remains the most established reperfusion strategy for high-risk PE; however, large-bore mechanical thrombectomy (LBMT) is increasingly being utilised in selected clinical phenotypes. Its role as upfront therapy in selected high-risk phenotypes is not well defined, though recent international guideline updates suggest a shift towards consideration of LBMT in certain patients.

To describe real-world treatment pathways and outcomes in high-risk PE managed within a multidisciplinary Pulmonary Embolism Response Team (PERT) model, focusing on phenotype-directed use of upfront and rescue LBMT.

We performed a retrospective single-centre case series of consecutive patients with high-risk PE managed by a PERT between July 2024 and March 2026. High-risk PE was defined by haemodynamic instability per European Society of Cardiology criteria. Patients were categorised into primary LBMT (Inari FlowTriever) or systemic thrombolysis, with rescue LBMT for clinical deterioration. Outcomes were reported descriptively.

Twenty-three patients were included (mean age 57.5 years). Severe shock was common (mean lactate 3.71 mmol/L; vasopressor use 81%), and 41% had contraindications to thrombolysis. Primary LBMT was performed in nine patients. Fourteen patients received systemic thrombolysis, including five presenting with cardiac arrest. Three thrombolysis-treated patients (21%) subsequently underwent rescue LBMT for persistent shock physiology or failed clinical response. In-hospital mortality was 13% (PE-related 9.5%). LBMT produced consistent haemodynamic improvement without procedural complications. Bleeding occurred predominantly in the thrombolysis group, including one fatal haemorrhage.

LBMT appears feasible as an upfront strategy in selected high-risk PE cases, particularly in patients with elevated bleeding risk or temporally stable shock, and may serve as effective rescue therapy following thrombolysis failure.