Breakthrough Blood Return Technology Reduces Surgical Blood Loss by 97 Percent During Pulmonary Embolism Procedures

The ENGULF trial finds that the Hēlo Blood Return System virtually eliminates blood loss during pulmonary embolism procedures while improving clot removal.

By: AXL Media

Published: Apr 25, 2026, 9:06 AM EDT

Source: Information for this report was sourced from EurekAlert!

A Technological Solution to Hemorrhagic Risks in Pulmonary Care

In a significant advancement for interventional cardiology, researchers at the SCAI 2026 Scientific Sessions in Montreal have unveiled results from the ENGULF trial showing a near-total reduction in surgical blood loss. By utilizing a specialized blood return system during continuous aspiration thrombectomy, medical teams can now address pulmonary embolisms with unprecedented safety. This development addresses a long-standing clinical dilemma where physicians were often forced to prematurely end clot-removal procedures to avoid life-threatening blood loss, frequently leaving dangerous remnants behind in the patient's lungs.

Challenges of Traditional Mechanical Thrombectomy Methods

Mechanical thrombectomy has emerged as a vital minimally invasive option for patients suffering from pulmonary embolism, a condition where blood clots obstruct the arteries in the lungs. However, the vacuum-like aspiration required to extract these dense clots traditionally draws a significant volume of the patient's own blood out of the body. This risk of severe bleeding has historically limited the thoroughness of the procedure, forcing a delicate and often precarious balance between effective clot disruption and the maintenance of the patient's overall blood volume and pressure.

The ENGULF Trial and the Hēlo Thrombectomy System

The ENGULF study serves as a prospective, investigational device exemption trial designed to evaluate the Hēlo Thrombectomy System. This analysis compared 130 patients, with 40 individuals receiving treatment through the novel Blood Return System and 90 undergoing standard aspiration without blood return. The system operates by simultaneously disrupting the clot and filtering the aspirated blood, which is then immediately returned to the patient. This study marks the first time that both the safety of the return process and the actual quality of the recycled blood have been rigorously assessed in a clinical setting.