Extravascular Defibrillator System Treats Abnormal Heart Rhythms

By HospiMedica International staff writers
Posted on 20 Feb 2023

Image: EV-ICD defibrillation lead placed outside of heart and veins, preserving vasculature (Photo courtesy of Medtronic)

Implantable cardioverter-defibrillators (ICDs) are used to provide life-saving therapy for patients at risk of sudden cardiac arrest (SCA), an electrical problem with the heart due to a dangerously fast heart rate (ventricular tachycardia or ventricular fibrillation). SCA can be fatal if it is not treated immediately. Traditional, transvenous ICDs are implanted in the chest and attached to leads that are threaded through the veins into the heart to sense the heart's electrical signals and deliver therapy to terminate a potentially fatal arrhythmia, restoring the heart's normal rhythm. Now, a new extravascular defibrillator system provides the life-saving benefits of traditional ICDs while avoiding certain risks because its lead (thin wire) is placed outside the heart and veins.

Patients implanted with the Aurora EV-ICD system from Medtronic plc (Dublin, Ireland) have defibrillation, anti-tachycardia pacing (ATP), and back-up pacing therapies available to them via a single implanted device that is similar in size, shape, and longevity to traditional ICDs. The system approval also includes proprietary procedure implant tools. The Aurora EV-ICD is implanted below the left armpit (in the left mid-axillary region) and the Epsila EV lead is placed under the breastbone (sternum) using a minimally invasive approach. Placing the lead outside of the heart and veins is designed to help avoid long-term complications that may be associated with transvenous leads, such as vessel occlusion (narrowing, blockage or compression of a vein) and risks for blood infections.

In a global pivotal study, the device's effectiveness in delivering defibrillation therapy at implant was 98.7%. This indicates a greater defibrillation efficacy for the EV-ICD than historical transvenous ICD studies, and comparable efficacy to the subcutaneous ICD despite EV-ICD's smaller device size. Further, the efficacy of ATP – which paces the heart to interrupt and terminate a dangerous rhythm, potentially avoiding a defibrillation shock – in the EV ICD study was comparable to ATP efficacy in transvenous defibrillators. In total, 33 shocks were avoided by having ATP programmed "on." Additionally, at six months, 92.6% of patients in the pivotal study were free from major system and/or procedure-related major complications such as hospitalization, system revision, or death. There were no major intraprocedural complications, nor any unique complications observed related to the EV-ICD procedure or system.

The Aurora EV-ICD system is indicated for patients who are at risk of life-threatening arrhythmias, and who have not had a prior sternotomy and do not need chronic bradycardia (abnormally slow heartbeat) pacing. The Aurora EV-ICD system includes features available in Medtronic transvenous ICDs, and offers additional advantages that are not available with subcutaneous ICDs. Medtronic has received CE (Conformité Européenne) Mark for the Aurora EV-ICD MRI SureScan (Extravascular Implantable Cardioverter-Defibrillator) and Epsila EV MRI SureScan defibrillation lead to treat dangerously fast heart rhythms that can lead to sudden cardiac arrest. The CE Mark approval follows the EV ICD Pivotal Study meeting its safety and effectiveness endpoints. The Aurora EV-ICD system is expected to be commercially available in autumn 2023 in select countries in Europe.

"We are proud to be the first company to offer a complete one-system, one-procedure extravascular ICD solution, which maintains the patient benefits of traditional, transvenous ICDs without the risk of leads in the heart and vasculature," said Alan Cheng, M.D., chief medical officer of the Cardiac Rhythm Management business, which is part of the Cardiovascular Portfolio at Medtronic. "This approval is a significant milestone in achieving our goal of delivering a defibrillation solution that treats sudden cardiac arrest while improving the patient experience."

Related Links:
Medtronic plc