FDA clears first PE thrombectomy system with integrated blood return

Overview

Updated 54 minutes ago

The FDA cleared two devices that together form a pulmonary embolism thrombectomy platform with integrated blood return. Endovascular Engineering's Hēlo system removes clots from the lungs while filtering and returning the patient's own blood, cutting median blood loss by 97% in the ENGULF trial.

Continuous aspiration thrombectomy has a known problem: it pulls out significant blood along with the clot, sometimes hundreds of milliliters. E2's approach returns that blood to the patient. The dual clearances let the company sell the complete system, and the trial data suggests it may make PE procedures faster and safer.

Why it matters

Pulmonary embolism is a leading cause of cardiovascular death; removing clots with near-zero blood loss could make mechanical treatment safer and more common.

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Key Indicators

97%

Median blood loss reduction with blood return

ENGULF trial: 10cc median blood loss with blood return vs 340cc without (p<0.001)

88%

Single-pass completion rate with blood return

Procedures completed with a single pass through the heart, vs 72% without blood return

Major adverse events in blood return group

0 of 40 patients in the BRS group vs 1.1% (1 of 90) without blood return

15F

Crossing profile

Low-profile catheter with 24F clot ingestion funnel for large-bore removal

Voices

Curated perspectives — historical figures and your fellow readers.

Ever wondered what historical figures would say about today's headlines?

People Involved

Dan Rose

Chief Executive Officer, Endovascular Engineering

Leading commercial launch of the Hēlo platform

Organizations Involved

Endovascular Engineering, Inc. (E2)

Medical device company

Commercial-stage company launching the Hēlo platform

Commercial-stage medical device company focused on treating venous thromboembolism, based in Menlo Park, California.

U.S. Food and Drug Administration

Federal regulatory agency

Granted 510(k) clearances for Hēlo devices

The US agency responsible for regulating medical devices, including the 510(k) clearance pathway for moderate-risk devices.

Timeline

December 2025 October 2026

4 events Latest: Today

Tap a bar to jump to that date

October 2026
FDA grants dual clearances for Hēlo platform
Today Regulatory

FDA cleared both the Hēlo Thrombectomy System and Hēlo Return, creating the first blood-return system cleared for continuous vacuum aspiration.
Today
April 2026
Blood quality data presented at SIR Annual Meeting
Clinical

E2 presented blood quality testing data at the Society of Interventional Radiology Annual Scientific Meeting, supporting the blood return system.
April 2026
2026
ENGULF comparative analysis presented at SCAI
Clinical

ENGULF trial data presented at SCAI Scientific Sessions in Montreal showed 97% blood loss reduction with the blood return system.
2026
December 2025
FDA clears Hēlo Thrombectomy System
Regulatory

FDA granted 510(k) clearance for the Hēlo Thrombectomy System under K252956, following ENGULF IDE study data.
December 18th, 2025

Scenarios

Hēlo platform gains rapid adoption in PE treatment

Likely Resolves by Oct 12, 2027

Discussed by: E2 leadership, SCAI presenters

E2 scales its commercial launch across US hospitals, using the dual clearances and ENGULF data showing 97% blood loss reduction and 88% single-pass rates. If adoption accelerates, the platform could become a standard option for PE thrombectomy, competing directly with Inari's FlowTriever and Penumbra's Indigo.

Competitors develop blood return systems

Possible Resolves by Oct 12, 2028

Discussed by: Industry analysts, competing device makers

Inari Medical and Penumbra respond to Hēlo's blood return advantage with their own systems. The ENGULF data showing 97% blood loss reduction raises the bar for the category, and rivals may need to match it to stay competitive.

Adoption lags on cost and training

Possible Resolves by Oct 12, 2027

Discussed by: Hospital procurement analysts

Hospitals weigh the cost of the new platform against existing thrombectomy options. The steerable catheter and blood return workflow require training, and reimbursement for the added blood return component is not yet established. Uptake could be slower than the clinical data suggests.

Historical Context

2 moments from history that rhyme with this story — and how they unfolded.

December 2014 - 2015

Stroke thrombectomy trials (2014-2015)

Five randomized trials — MR CLEAN, ESCAPE, EXTEND-IA, SWIFT PRIME, and REVASCAT — showed that mechanical clot removal plus standard care beat standard care alone for acute ischemic stroke. The results were so clear that several trials were stopped early for efficacy.

Then

Mechanical thrombectomy became the standard of care for large-vessel occlusion stroke within months of the results.

Now

The trials transformed stroke treatment, drove rapid device innovation, and reshaped hospital investment in neurointervention.

Why this matters now

Like stroke thrombectomy, PE thrombectomy is a mechanical approach displacing or supplementing drug therapy. Hēlo's blood return capability addresses a key limitation of continuous aspiration, potentially accelerating adoption the way trial data did for stroke.

2010s

Mechanical thrombectomy for PE emerges (2010s)

Inari Medical's FlowTriever and Penumbra's Indigo system brought mechanical thrombectomy to pulmonary embolism, offering an alternative to systemic thrombolysis with its bleeding risk. These devices established the category Hēlo now enters.

Then

Mechanical thrombectomy gained acceptance for submassive and massive PE, with multiple IDE trials validating safety and efficacy.

Now

The category grew into a competitive market, with device makers competing on clot removal efficiency, catheter profile, and procedural outcomes.

Why this matters now

Hēlo enters an established category but adds a feature competitors lack — integrated blood return. This could reset expectations for what a PE thrombectomy system should do.