Index procedure: electro-anatomical mapping (EAM) and associated RF ablation lesions
After EIVM and visualization of LA myography, the acute effect of EIVM was assessed by repeated LA voltage mapping (see below). PVI was completed in case of PV reconnection on both sides. A roof line was performed or completed and the MI line was completed endocardially (mitral annulus side) and epicardially by RF applications within the CS. Electrical cardioversion was then performed in the absence of organization to an LA flutter or regularization to SR. Bidirectional blocks of PV, MI and roof lines were then assessed by activation mapping and differential pacing.16 Cavotricuspid isthmus ablation was then performed (or bidirectional block assessed). All lines were re-assessed 30 min later. All ablations involved the 3.5-mm, bidirectional, open-irrigated, contact force-sensing SmartTouch SurroundFlow catheter (Johnson & Johnson, Irvine, CA). Involved RF powers included 50 W at the endocardial MI (target ablation index 450–500), 25 W in the CS (target ablation index 300), 30 to 40 W in the LA (target ablation index 430 anterior and 380 posterior) and 40 W at the cavotricuspid isthmus (target ablation index 450).