Atrioventricular nodal re-entry tachycardia (AVNRT) is
the most common benign supraventricular tachycardia{Kastor, 1975 #14}. The
underlying substrate for the arrhythmia was first proven by Denes et al. in 1973 as being the presence of dual atrioventricular
(AV) pathways {Denes, 1973 #3}. Although present in about 20 to 30% of people,
AV nodal duality only gives rise to symptomatic tachycardia in about 3% of this
subgroup {McCanta, #18}. Therapeutic
options for symptomatic patients consist of both medical therapy and ablation.
Several class I, II and IV anti-arrhythmic drugs are used to treat AVNRT.
However, since the majority of patients suffering from AVNRT are in their
second and third decade of life, a long-lasting drug therapy is not the most
preferred option. Therefore radiofrequency (RF) ablation for AVNRT was
introduced in 1982 by Gallagher et al {Gallagher, 1982 #7}. The initial target for
ablation was the fast pathway {Langberg, 1989 #16}. This approach soon proved
to have some deleterious side effects such as complete atrioventricular block in
10%-20% {Epstein, 1989 #6} and so the target for ablation was moved to the slow
pathway in most patients. Nowadays two
options are available to ablate the slow pathway: focal cryoablation or RF
ablation. Both techniques come with different advantages and disadvantages. This
paper is dedicated to make a historical comparison between both techniques,
evaluate results published in literature and comment on possible pitfalls in using
cryo- and RF ablation.
Credits: Riahi Leila; Prisecaru Raluca; De Greef Yves; Stockman Dirk; Schwagten Bruno