Elimination of distal coronary sinus (CS) to left atrial (LA) connections reduced atrial arrhythmia recurrences compared to standard pulmonary vein (PV) isolation and non-PV trigger ablation in patients undergoing a first atrial fibrillation (AF) ablation procedure findings of a small randomised study, published in Circulation: Arrhythmia and Electrophysiology has found.
Authors of the study Ling Kuo (Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA) et al write that it has previously been shown that the presence of dual muscular CS to LA connections, coupled with rate-dependent unidirectional block in one limb, is associated with AF induction.
PRECAF—Prospective Elimination of Distal Coronary Sinus to Left Atrial Connection for Atrial Fibrillation Ablation—sought to examine whether ablation of distal CS to LA connections at a first AF ablation reduces arrhythmia recurrence during follow-up.
A total of 35 consecutive patients with drug refractory AF undergoing first time ablation between August, 2018 and August, 2019, were randomly assigned to receive either standard ablation (PV isolation and non-PV trigger ablation), versus standard ablation plus elimination of distal CS to LA connections by targeting the earliest LA activation during distal CS pacing with a deca-polar catheter placed with its proximal electrode at the ostium.
Change of the local CS atrial electrogram and LA activation sequence to early activation of the LA septum or roof during distal CS pacing were the endpoint for CS-LA connection elimination.
The study team report that 30 patients completed six months study follow-up (15 patients in each group). Demographic characteristics including age and AF persistence were similar in both groups. After a mean follow-up of 170±22 days, there were seven atrial arrhythmia recurrences in the standard group and one recurrence in the CS-LA connection elimination group (46.7% vs 6.7%, HR 0.12, P=0.047).
In conclusion the study team reports that elimination of distal CS to LA connections reduced atrial arrhythmia recurrences compared to standard PV isolation and non-PV trigger ablation in patients undergoing a first AF ablation procedure.