Real-time global control index for adaptive atrial resynchronization: a quantitative feedback mechanism for non-destructive AF therapy
K Sinha, B J D Doliner, T J C Corvi, D C Chou, P S N Safavi-Naeini, M M J John, D J B Bernard, L M J Jaworski, B A C Coppola, B A C Bomela, R W Werneth, M R RazaviAbstract
Introduction
Left atrial multi-site pacing (LAMSP), delivered through Spatial Resynchronization Therapy (SRT), restores functional sinus rhythm by coordinating atrial activation without tissue ablation. To enable closed-loop control, clinicians require quantitative metrics of atrial organization during therapy delivery. We developed and validated a real-time Global Control Index (GCI) to quantify the degree of atrial coordination and guide the optimization of LAMSP parameters.
Methods
The LAMSP System employs spatially distributed multi-site epicardial electrodes spanning anterior, posterior, and lateral left atrial surfaces and the right atrium. The proprietary GCI algorithm continuously quantifies spatial coordination (0–100 scale) using three features: (1) activation sequence consistency, (2) cycle-length stability, and (3) propagation coherence across electrode arrays. Six patients with inducible AF underwent LAMSP with concurrent GCI monitoring.
Results
The GCI distinguished three activation states: (1) baseline AF (0–30), (2) regional control (30–70), and (3) global control (≥70). Global control was achieved within 1.5–4 s of LAMSP initiation. A decline in GCI preceded visual loss of coordination by 0.5–1.5 s, demonstrating predictive capability. Sustained GCI > 80 for > 10 s predicted AF termination in all responsive patients (4/4), while intermittent fluctuations (65–85) indicated transient organization in advanced AF.
Conclusions
The Global Control Index provides the first real-time quantitative measure of atrial coordination during LAMSP. By enabling closed-loop, adaptive pacing control, GCI supports functional sinus rhythm restoration without tissue injury. This physiologic metric may guide therapy optimization, predict termination success, and define a new standard for intelligent atrial resynchronization monitoring.