Posted by Carl Plaskett on May 13, 2004 at 15:34:59:
In Reply to: Post PVI at the C.C. posted by Chris Muscato on May 13, 2004 at 01:59:14:
When related to a PVI/PVA, I believe stenosis is a narrowing of the opening of the pulmonary veins where they attached to the atrium wall. This "narrowing" is usually the result of the scar tissue the EP created with his ablation tip/tool to block those pesky errant electrical impulses. Some folks have very small openings and scar tissue can easily create a partial blockage. Too much energy, too close or long with the "tip" or the wrong selection of tip can contribute to excessive scarring.
If you refer back to Sarah's report from the Afib Summit, which she posted several months ago, I believe the consensus was that blockage of less than 60% is not a problem. She also reported that at the Cleveland Clinic, unlike MOST facilities, the EP has multiple engergy sources/tips/tools available in the EP Lab during a PVI/PVA procedure, so if he feels one isn't suitable for a particular patient (narrow pulmonary openings, thicker or thinner atrium wall, etc.), he can quickly change to the more appropriate (for that patient) energy source, etc. This is a luxury not available at most hospitals, and may partially account for their higher than average success rate and lower than normal stenosis. They still follow up for several months to confirm that stenosis has not developed or increased.
EPs who have only one energy source, etc., are at a disadvantage, in MY opinion, since they have to do what they can with what they have. It doesn't surprise me that stenosis/strokes are more of a risk at some facilities.