Je. Olgin et al., PATHOLOGICAL FINDINGS FOLLOWING SLOW PATHWAY ABLATION FOR AV NODAL REENTRANT TACHYCARDIA, Journal of cardiovascular electrophysiology, 7(7), 1996, pp. 625-631
Introduction: AV nodal reentrant tachycardia is routinely cured using
radiofrequency catheter ablation techniques, However, there remains co
ntroversy as to whether the reentrant circuit for this tachycardia exi
sts solely in the AV node or whether perinodal atrial tissues are vita
l to the circuit, In addition, the effects of radiofrequency ablation
of the slow pathway of AV nodal reentrant tachycardia on the AV node a
re not known, We examined an autopsy specimen to determine the anatomi
cal location and extent of AV nodal damage of radiofrequency slow path
way ablation for cure of AV nodal reentrant tachycardia. Methods and R
esults: A 64-year-old woman with confirmed AV nodal reentrant tachycar
dia underwent a successful ''slow pathway'' AV modification with a sin
gle radiofrequency application. Five months after the procedure, the p
atient died from a spontaneous intracranial hemorrhage. Postmortem gro
ss pathological examination of the heart was performed, The heart was
then sectioned and stained for histologic examination, On gross examin
ation, a pale lesion 0.5 cm in diameter was seen on the endocardial su
rface adjacent to the tricuspid annulus, approximately 0.85 cm anterio
r to the coronary sinus os and 1.15 cm from the apex of the triangle o
f Koch where the AV node resides, Histologic examination revealed a ri
ght atrial lesion composed of connective tissue and fat, The compact A
V node and surrounding transitional cells were unaffected histological
ly, with normal atrial cells lying between the AV node and the lesion.
Conclusion: Ablation of the slow pathway to cure AV nodal reentrant t
achycardia does not produce any gross or histologic damage to the AV n
ode, suggesting that the AV nodal reentrant circuit does not exist in
its entirety in the AV node.