Purerfellner H., Aichinger J., Martinek M., Nesser H.J., Janssen J, 13
“Short- and long-term experience in pulmonary vein segmental ostial ablation for
paroxysmal atrial fibrillation”
Our results demonstrating a stable cure rate over an extendend period are confirmed in a
previously published larger report11. However, it remains interesting to reconfirm those data by
our own series of patients having undergone a 4 PV ablation approach from the second half ot
the year 2002 onwards.
Learning curve
To find an appropriate measure for our learning curve we have analyzed the number of
secondary procedures and the success rates . As depicted in figure 1 there is a constant decrease
of secondary procedures per patient with growing experience : The percentage decreases from
about 50% in patients with their primary procedure in the year 2001 to 40% and 25%,
respectively in patients who underwent PVI in the year 2002 and 2003. The reason for this is
based on the growing knowledge about the nature of early recurrences (within the first days after
the primary procedure): As those recurrences may merely represent transient effects of leason
healing we tended to treat those arrhythmias conservatively with growing experience by
administering antiarrhythmic drugs instead of performing an early redo procedure. In addition ,
we were able to exactly quantify and publish the decrease of arrhythmic burden of PAF within
the first 3 months after PVI in 12 patients who were previously implanted with a last generation
implantable pacemaker offering extended storage capabilities (Medtronic Inc, AT 500)9. Figure
4 demonstrates the success rate based on the year of the primary procedure. It shows an increase
in the CS from 40% in the year 2001 to about 50% in the next two years. The most likely cause
for this is the fact that the procedure changed from a 3 PV to a 4 PV isolation approach
(including the RIPV) . The CRR, however, remains fairly constant, reaching 70 to 80%.
Redo procedures
In general, concomitant atrial tachycardias or atrial flutter were not a primary target for
ablation during the first ablation session. In case of a recurrence of PAF, one or more PVs were
usually reconnected and had to be reisolated. In addition, sustained atrial tachycardias as well as
right or left atrial flutter circuits were mapped as appropriate. However, no detailed ablation
results for these substrates are available in this reported patient series.
Complications
With regard to diagnosis, management and outcome in PV stenosis follwing ostial PVI
we may refer to our previously published results6,7. Despite the fact that there may be multiple
factors operational for the occurence of PV stenosis (energy source, amount of delivered energy,
localisation of the affected PV) the exact site of energy delivery at the ostial level seems to be of
highest importance: The more energy delivered within a PV (versus ostial) the higher the chance
of developing significant PV stenosis. In general, the symptom threshold (including dyspnea,
hemoptysis and pneumonia) for significant PV narrowing exceeds 60% of luminal narrowing,
however, not every single significant PV narrowing produces symptoms. Lung scanning is a
useful diagnostic test to document hemodynamically significant PV stenosis by detecting a
segmental perfusion deficit. Interventions in significant PV stenosis including PV dilatation
and/or stenting may lead to a high reocclusion rate. In our published series of 6 patients with
predominant single PV stenosis the clinical outcome is beneficial despite reocclusion in 2
patients during a longterm follow up.
Limitations
Longterm success is based on the results in patients with a 3 PV ostial isolation approach
(sparing the RIPV). It may well be that chronic results in patients with a 4 PV (including the
RIPV) approach are superior.
Although routine longterm ECG monitoring was performed at prespecified points in time
Indian Pacing and Electrophysiology Journal (ISSN 0972-6292), 6(1): 6-16 (2006)