MINERVA: Managed atrial, ventricular pacing reduced AF development in bradycardia

Issue: September 2014

SAN FRANCISCO — An advanced pacing feature was associated with reduced development and progression of persistent atrial fibrillation in patients with bradycardia, according to new data from the MINERVA study.

Perspective from Kevin Heist, MD

Researchers assigned patients with bradycardia and dual-chamber pacemakers who had a history of paroxysmal or persistent AF or atrial tachyarrhythmias (AT/AF) to standard dual-chamber pacing (n=385), managed ventricular pacing (n=398) or atrial preventive pacing and atrial antitachycardia pacing plus managed ventricular pacing (Reactive ATP, Medtronic; n=383).

At 2 years, incidence of persistent AT/AF was 26% (95% CI, 22-31) in the standard pacing group, 25% (95% CI, 21-30) in the managed ventricular pacing group and 15% (95% CI, 12-20) in the Reactive ATP group (HR for Reactive ATP vs. standard pacing=0.52; P<.001; HR for Reactive ATP vs. managed ventricular pacing=0.57; P=.002), according to results presented at the Heart Rhythm Society Annual Scientific Sessions.

High efficacy of Reactive ATP (>44%) was an independent predictor of reduced persistent AT/AF (HR=0.42; 95% CI, 0.21-0.83), according to Luigi Padeletti, PhD, from the University of Florence, Italy.

Compared with those in the standard pacing group, those in the Reactive ATP group showed a 58% relative reduction in the development of persistent AF and a 52% relative reduction in AF-related hospitalizations and ED visits (P<.001 for both), according to a Medtronic press release.

“Surprisingly, many episodes we thought to be AF actually start or periodically evolve into slower, more regular rhythms,” Padeletti stated in the release. “By effectively terminating those rhythms, Reactive ATP appears to be the primary pacing feature significantly delaying AF progression in patients with Medtronic pacemakers.” – by Erik Swain

For more information:

Padeletti L. Abstract LB03-06. Presented at: Heart Rhythm Society Annual Scientific Sessions; May 7-10, 2014; San Francisco.

Disclosure: Padeletti reports receiving research grants from Boston Scientific, Medtronic and St. Jude Medical.

Perspective

Kevin Heist, MD

Maintenance of sinus rhythm in patients with a history of AT/AF is a challenging goal, often requiring antiarrhythmic drug therapies and ablation procedures. Investigational atrial defibrillators used in the past were effective at terminating AT/AF, but were poorly tolerated due to painful shocks and never reached mainstream use. Prior studies have shown increased incidence of AT/AF with increased right ventricular (RV) pacing (and reduced AF with avoidance of RV pacing), but most prior studies of atrial overdrive and antitachycardia pacing (ATP) have failed to demonstrate a benefit in regard to AT/AF burden.

In this well-performed study, more than 1,000 patients were randomly assigned to three arms: standard DDDR pacing, managed ventricular pacing (to minimize RV pacing) or DDDR pacing with both ATP and MVP (DDDRP+MVP). There was no benefit demonstrated when comparing MVP with DDDR in regard to atrial arrhythmia burden, but DDDRP+MVP demonstrated a significantly lower incidence of persistent AF compared to either of the other randomization arms. As has also been demonstrated for ATP for ventricular arrhythmias with implanted defibrillators, atrial ATP was less successful in terminating arrhythmias with very high rates. At a time when enthusiasm for device-based AT therapy was clearly waning based on prior negative studies, this current study reignites hope that device-based therapy may terminate AF and other AT. While the data are not yet strong enough to advocate device placement solely for suppression of these arrhythmias (absent a pacing indication), atrial ATP may prove to be an important adjunct to other strategies to maintain sinus rhythm.

Kevin Heist, MD

Assistant Professor of Medicine in Cardiac Electrophysiology

Harvard Medical School

Massachusetts General Hospital Institute for Heart, Vascular and Stroke Care

Disclosures: Heist reports consulting for Boston Scientific and St. Jude Medical and receiving honoraria from Biotronik and St. Jude Medical for educational lectures.