DISCUSSION:
Typical AVNRT is the most common cause for SVT and slow pathway ablation
provides long term cure in > 95% of patients. To date
there is a paucity of prospective studies evaluating the acute impact of
catheter ablation in the region of the slow pathway on inducibility of
AVNRT. Prior retrospective studies exploring the characteristics of JR
have reported variable outcomes on slow pathway
conduction26, 37, 38. In the present study we
prospectively evaluated the impact of each individual radiofrequency
application on slow pathway conduction. The main findings were:
- Junctional rhythm was required during RFA for successful slow pathway
ablation in all;
- The median cycle length of junctional rhythm was similar during
effective and ineffective RF applications (587 ± 150 vs 611 ± 193 p =
0.4);
- Junctional atrial (JA) block during faster junctional rhythm was
associated with a high likelihood of successful slow pathway
modification and;
- RF applications as short as 5-10 seconds can result in successful
modification of the slow pathway.