Medtronic has presented data from the ALSYNC (Alternate Site Cardiac Resynchronization) study evaluating the safety and performance of a new delivery system and left ventricular endocardial (LVE) pacing lead for CRT implantation.

According to Medtronic, the ALSYNC study results showed that heart failure patients who have limited options for implanted device therapy may benefit from a novel implant technique for cardiac resynchronization therapy (CRT) devices.

The ALSYNC study involved 138 patients at 18 centers in Europe and Canada. These patients were indicated for CRT, but were unable to receive a conventional system or did not respond to the therapy at least six months post-implant.

Primary objective of the study was to demonstrate that the complication rates were less than 30% at six months in patients with an implant attempt. The study has met the primary objective with an observed rate of 17.7%.

The study results showed that LVE pacing from inside the heart’s left ventricle was successful in 118 patients out of 133 (89%) of implant attempts.

Some heart failure patients are not suitable for, or do not respond to, traditional CRT due to limitations associated with implanting a lead, or thin wire, in veins on the outside of the left ventricle; these limitations may include unique patient anatomy or suboptimal lead placement.

As a potential alternative for these patients, the system evaluated in the study implants a lead placed inside the left ventricle by crossing the atrial septum.

Dr John Morgan from Southampton University Hospitals Trust, Southampton, the UK, noted that there is a significant need for a new way to pace the left ventricle in patients unable to receive the clinical benefits of standard CRT therapy, and this study suggests left ventricular endocardial pacing is a feasible option.

"These findings will elevate this new approach from something that is investigational to one that is closer to the mainstream," Dr Morgan added.

The system evaluated in the ALSYNC study is not available for investigational or commercial use in the US.