Patient Characteristics
A cohort of 65 consecutive patients with AT/flutter who were referred to
our institution for radiofrequency (RF) catheter ablation between April
2018 and December 2020 were evaluated retrospectively. Of these 65
patients, a total of 8 patients (5 men and 3 women) with more than two
types of stable ATs during ablation were included in this study. The
patients with unstable cycle length (CL), unsustainable ATs and in whom
ablation failed were excluded due to the unascertainable mechanism of
these ATs. Seven patients had permanent AT, and 1 patient had paroxysmal
AT for an average of 12 months (range, 1 month to 36 months) despite the
use of antiarrhythmic drugs. All patients had been on oral
anticoagulants before ablation. Transesophageal echocardiography was
performed to rule out left atrial (LA) thrombi in all patients. Oral
anticoagulants were stopped at admission and replaced with intravenous
heparin to maintain partial thromboplastin time at 2 to 3 times the
control value. This was stopped 6 to 8 hr before ablation for
transseptal puncture. All patients gave written informed consent, and
the study protocol was approved by the local Research and Human Ethics
Committees.