The catheter based pulmonary vein conduit isolation

Currently we are performing catheter based pulmonary vein conduit isolations.  These procedures are different from "simple" pulmonary vein isolations in that the entire conduit feeding the vein pair on both the right and left sides of the left atria are isolated.  Ablation in the pulmonary vein antral regions or vestibules is known to increase the chances for cure from atrial fibrillation over that seen with ostial vein isolations alone.  This procedure also includes linear ablations lines across the roof of the left atria and across the posterior LA wall and a linear lesion in the left atrial isthmus region (ie the region between the left lower pulmonary vein ostia and the mitral annulus).  This procedure is thus the equivalent of a catheter based maze procedure.  Atrial fibrillation (especially in chronic or persistent atrial fibrillation patients) will often involve more then the pulmonary veins alone.  The success rate for catheter based maze procedures in these patients is up to 80% and is far higher then that seen for pulmonary vein isolations alone.

An electroanatomical map of a patients left atria prior to the right pulmonary quadrant being isolated.  The right pulmonary veins are the yellow and grey veins on the left of this map.  The red dots are a series of linear ablation lesions place during the ablation procedure.  The yellow color to the left of the red dots indicates the right common pulmonary conduit (or "trunkus") is electrically active prior to the ablation and thus contains potentially arrhythmia inducing substrates.

Following the ablation lesions a repeat electroanatomical voltage map of the patients heart is constructed.  All myocardium in the right common pulmonary vein trunkus is now red in color.  Red color on this map indicates the absence of electrical activity (yellow, green and blue are healthy) and shows that the common right pulmonary vein trunkus has been electrically disconnected from the rest of the left atria as a result of the ablations performed.  This particular patient had undergone two previous pulmonary veins isolation procedures but continues to suffer from atrial fibrillation.  This procedure has to date resulted in cure for this patients atrial fibrillation.