• Late-breaking study presented at HRX 2026 met primary feasibility endpoint in 100% of patients
• Majority of patients had minimal or no AF symptoms at 12 months
• STAR Apollo™ Mapping System identifies atrial fibrillation (AF) drivers based on the fundamental electrophysiological principles of activation precedence

LA JOLLA, Calif. and LONDON, Sept. 22, 2026 /PRNewswire/ — Rhythm AI, a MedTech company developing AI-powered mapping software for electrophysiologists treating atrial fibrillation (AF), today announced results from the STAR Apollo study (NCT05826665) evaluating the company’s STAR (Stochastic Trajectory Analysis of Ranked signals) mapping approach in redo ablation procedures of patients with persistent AF. The results were simultaneously published in the Heart Rhythm Journal and presented by Dhanunjaya R. Lakkireddy, MD, FHRS, Executive Medical Director of the Kansas City Heart Rhythm Institute during the Late-Breaking Clinical Trials session at HRX 2026 in Atlanta.

“After a first ablation fails, the hardest question is knowing where to go next, beyond the pulmonary veins. STAR Apollo gives us a way to answer that using a catheter and mapping system already in the lab. It’s not a black box but built on the same activation-timing principles electrophysiologists have relied on for decades, just applied automatically and at a scale no one could manage by hand. In this study, that translated into 90% of patients in sinus rhythm at the 1-year follow-up visit, which is an encouraging signal,” commented Dr. Lakkireddy.

The prospective, single-arm STAR Apollo study was conducted across four U.S. centers in 50 patients undergoing redo ablation for persistent AF that had recurred after a prior pulmonary vein isolation (PVI). One in three patients will undergo a repeat ablation for AF and re-isolation of the PVI alone is often insufficient.¹ The STAR Apollo Mapping System provides a precise, patient-specific map of AF drivers by identifying Repetitive Patterns of Activation (RPAs) and Early Sites of Activation (ESAs) and is compatible with the two most widely used 3D mapping platforms in clinical practice.

The late-breaking one-year data for the 50-patient STAR Apollo study showed:

• The primary endpoint (procedural feasibility) was met in 100% of patients.
• 90% of patients were free of AF at the 1-year follow-up.
• Very few patients had reinterventions, with analyses showing that 73% of patients had no recurrence of arrhythmia at all.
• A limited number of sites were targeted per patient.
• A strong safety profile with no procedure-related deaths, stroke or atrioesophageal (a/o) fistulas.
• STAR mapping added very little time to the case, which had a median time of just over two hours.

“These are the kind of data that matter to us both clinically and commercially. STAR Apollo is already FDA-cleared and compatible with the two mapping platforms present in EP labs performing AF ablations,” said Mike Dineen, President & Chief Executive Officer of Rhythm AI. “This study shows clear evidence that our approach to locating AF drivers is effective and safe for this difficult-to-treat AF population and the results exceeded our expectations. That’s the evidence base we need as we prepare to expand physician access and conduct further evaluations of the STAR Apollo technology.”

About Rhythm AI
Rhythm AI is a MedTech company developing AI-powered software to help electrophysiologists treat atrial fibrillation more precisely and effectively. The company’s flagship product, STAR Apollo™, is an FDA-cleared solution that analyzes live electrogram data during electrophysiology procedures, identifying patient-specific Repetitive Sites of Activation and Early Sites of Activation for mapping discrete areas of interest to locate AF drivers. Founded in 2018 and headquartered in London, UK, Rhythm AI is committed to improving outcomes for the millions of patients living with atrial fibrillation who are currently underserved by current electrophysiology approaches. Learn more at https://rhythm-ai.com.

1. Sanchez-Somonte, P, et al. Incremental Efficacy for Repeat Ablation Procedures for Catheter Ablation of Atrial Fibrillation. JACC. 2024.

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SOURCE Rhythm AI