Medtronic has unveiled results from the Micra atrial tracking using a ventricular accELerometer (MARVEL 2) study of Micra Transcatheter Pacing System (TPS).

The results of MARVEL 2 trial demonstrated that an investigational set of algorithms used in Micra TPS would improve the synchrony and cardiac function in patients with impaired electrical conduction between the chambers of the heart, called atrioventricular (AV) block.

MARVEL 2 study co-principal investigator Larry Chinitz said: “Our investigation shows that accelerometer-based atrial-sensing algorithms can sense signals from the atrium in the heart and make calculated adjustments to when ventricular pacing occurs, thus improving coordination between the atrium and ventricle.

“These results provide further evidence that these novel investigational algorithms added to the Micra TPS may allow more patients, including those with normal sinus rhythm and AV block, to benefit from a leadless pacemaker.”

Medtronic’s Micra TPS device is the world’s smallest pacemaker

MARVEL 2 study enrolled 75 patients at 12 centres in Hong Kong, Malaysia, Europe and the US, to evaluate the safety and effectiveness of accelerometer-based atrial sensing algorithms, which were downloaded to the Micra TPS device.

The Micra TPS has been approved by the US Food and Drug Administration (FDA) in April 2016, for patients needing single-chamber pacemaker. The device marks the first and only leadless pacemaker approved for use in the US.

Forty patients with complete heart block and normal sinus rhythm were selected to be included in the primary efficacy analysis while all 75 patients were included in the primary safety objective.

In addition, the study evaluated the capability of Micra accelerometer to monitor and detect atrial contractions and enable coordinated pacing between the atrium and ventricle, thereby providing AV synchrony.

Medtronic said that the study has reached the primary safety objective, with no pauses or episodes of pacing-induced tachycardia during algorithm mediated AV synchronous pacing in any of the 75 patients.

The results of the study were published in the ‘JACC: Clinical Electrophysiology’ and the company intends to present the study results at American Heart Association Scientific Sessions 2019.

Based on positive results from both the MARVEL and MARVEL 2 studies, the company has filed an application with FDA to expand the indication for its Micra AV, to include AV block and normal sinus rhythm population.

Medtronic vice president and cardiac rhythm and heart failure division chief medical officer of medical affairs Rob Kowal said: “The results of MARVEL 2 build on the original promising MARVEL results and provide the strongest evidence to date that accelerometer-based atrial sensing with the Micra leadless pacemaker has the potential to provide improved AV synchrony in AV block patients, who make up approximately 40% of the pacemaker population worldwide.

“This first-of-its-kind approach to pacing is another example of Medtronic’s commitment to meaningful product innovation that will help patients around the world.”