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).