Left atrial anatomical contact areas were closely associated with low-voltage zones (80% overlap) and circular activation sites (55% proximity) in patients with persistent atrial fibrillation.
Observational (n=40)
Is there a spatial relationship between left atrial anatomical contact areas and circular activation sites in patients with persistent atrial fibrillation?
External anatomical structures contacting the left atrium may contribute to the formation of low-voltage zones and unique conduction properties necessary for maintaining persistent atrial fibrillation.
INTRODUCTION: Atrial low-voltage zones (LVZs) may be related to maintenance of atrial fibrillation (AF). The influence of left atrial (LA) contact areas (CoAs) on reentrant or rotor-like sources maintaining AF has not been investigated. METHODS AND RESULTS: Forty patients with persistent AF (PsAF) were analyzed. Three representative CoA regions in the LA (ascending aorta: anterior wall; descending aorta: left inferior pulmonary vein; and vertebrae: posterior wall) were visualized by enhanced CT. Using circular catheters, the LVZs (80% of the mean AF cycle length. A pivot was defined as the core of the localized circular activation. Anterior (39/40 patients, 98%), left pulmonary vein antrum (27/40, 68%), and posterior (19/40, 48%) CoAs were identified, and 80% (68/85) of those sites were overlapped by or close (<3 mm) to LVZs. Thirty-six (90%) patients demonstrated circular activation (3.1±1.7 sites/patients) along with significantly higher organized dominant frequencies (6.3 ± 0.5 Hz, regularity-index: 0.26 0.23-0.41) within the LA, and the average electrogram amplitude of those pivots was 0.30 mV (0.18-0.52). Of those sites, 55% (66/120) were located at or close to CoA regions. Catheter ablation including of LVZs neighboring CoAs terminated AF in 9 (23%) patients. CONCLUSIONS: External anatomical structures contacting the LA may be related to unique conduction properties in diseased myocardium necessary for PsAF maintenance.
Nakahara et al. (Mon,) conducted a observational in Persistent Atrial Fibrillation (n=40). Left atrial anatomical contact areas was evaluated on Overlap or proximity (<3 mm) of left atrial contact areas to low-voltage zones. Left atrial anatomical contact areas were closely associated with low-voltage zones (80% overlap) and circular activation sites (55% proximity) in patients with persistent atrial fibrillation.