Hydrogel endovascular aneurysm treatment (HEAT) clinical trial starts patient enrolment


MicroVention, a wholly owned subsidiary of Terumo, has announced initiation of patient enrolment in its HEAT (Hydrogel endovascular aneurysm treatment) clinical trial. 

This prospective, randomised, international multicentre trial is designed to compare clinical outcomes in patients with intracranial aneurysms treated with the new generation of the MicroVention hydrogel coils to those treated with bare platinum coils. The HEAT trial will enrol up to 600 subjects from approximately 30 sites around the world.

Bernard R Bendok, neurosurgeon at Northwestern Memorial Hospital, Chicago, USA, and principal investigator for the HEAT trial said: “Intracranial aneurysms can be a devastating, life threatening condition with approximately 30,000 people suffering from subarachnoid haemorrhage each year in the USA alone. The HEAT trial will allow us to better understand these lesions and advance their treatment.”

Richard Cappetta, president and CEO, MicroVention, said: “The HEAT trial is intended to provide evidence that our second-generation hydrogel coil technologies provide superior long-term clinical outcomes compared to bare platinum coils. In a recently published article in The Lancet reporting on our earlier HELPS trial results, MicroVention’s first-generation HydroCoil Embolic System demonstrated superior angiographic outcomes at 18 months compared to bare platinum coils.1 We believe that, with a comprehensive line of second-generation hydrogel technologies utilised in the HEAT trial, which includes the HydroFrame, HydroFill and HydroSoft embolic coils, improvement in clinical efficacy should be even greater compared to bare platinum coils. In addition, these new gel coils are much easier to use due to their increased repositioning time, softer delivery system and standardised microcatheter delivery.”

Click here to listen Bendok’s podcast about brain aneurysm symptoms and treatment.  


  1. White PM, Lewis SC, Gholkar A et al. Hydrogel-coated coils versus bare platinum coils for the endovascular treatment of intracranial aneurysms (HELPS): a randomized controlled trial. Lancet 2011; 377:1655-62.

About the HydroCoil Embolic System

The HydroCoil Embolic System is a unique non-bioactive endovascular embolization device combining MicroVention’s platinum microcoil technology with a proprietary hydrogel. The hydrogel polymer is a biomaterial that begins to swell after a brief period of contact with blood, giving physicians the ability to precisely control delivery of the device. Once the hydrogel swells, it provides improved filling of the aneurysm without exerting pressure onto the aneurysm wall or adjacent coils. The HydroCoil system combines the safety of platinum coils with the filling and mechanical stability of hydrogel. The HEAT trial will focus on the newer generations of the HydroCoil Embolic System that are designed for ease of use together with the benefits of hydrogel. The HydroCoil system offers a therapeutic alternative to the current treatment choices of platinum coils and neurosurgical clipping, and is also being used clinically to treat fistula and peripheral vascular lesions.