Importance of tachycardia cycle length for differentiating typical atrial flutter from scar-related in adult congenital heart disease.
BACKGROUND
Radiofrequency catheter ablation (RFCA) for intraatrial reentrant tachycardia (IART) in congenital heart disease (CHD) remains difficult.


METHODS
Thirty-four consecutive adult patients (age, 37.6 ± 12.8 years; male, 21) with previously repaired CHD and IART underwent an electrophysiological study and RFCA. CHD included atrial septal defect (ASD, n = 14), tetralogy of Fallot (n = 11), ventricular septal defect (n = 4), pulmonary atresia (n = 2), atrioventricular septal defect (n = 1), transposition of the great arteries (n = 1), and double-outlet right ventricle (n = 1).


RESULTS
Duration of CHD repair to IART onset was 19.1 ± 8.5 years. Thirty and four patients had single- and double-loop reentrant tachycardia, respectively. Among the total of 38 IARTs, which were mapped, 22 (57.9%) and 13 (34.2%) IARTs were cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) and scar-related AFL, respectively. Typical AFL electrocardiography findings including definite sawtooth appearance in inferior leads and positive F wave in lead V1 were observed in only 12 of 21 patients (57.1%) with CTI-dependent AFL. CTI-dependent AFL had a significantly longer tachycardia cycle length (TCL) than scar-related AFL (267.6 ± 34.4 ms and 235.9 ± 37.0 ms, respectively; P = 0.031). TCL > 250 ms had 79% sensitivity as the cutoff value for differentiating CTI-dependent from scar-related AFL. The acute success rates of RFCA in CTI-dependent and scar-related AFLs were 85.7% and 90.0%, respectively. The recurrence rates in CTI-dependent and scar-related AFLs were 11.1% and 11.1%, respectively, during a follow-up of 21.2 ± 28.3 months.


CONCLUSIONS
CTI-dependent AFL was the most common IART in adult patients with repaired CHD and was easily manageable by RFCA. TCL might help to differentiate CTI-dependent AFL from other IARTs.
Division of Cardiology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea.
Jae-Sun
JS
Uhm
Hee-Sun
HS
Mun
Jin
J
Wi
Jaemin
J
Shim
Hye Jin
HJ
Hwang
Jung-Hoon
JH
Sung
Jong-Youn
JY
Kim
Hui-Nam
HN
Pak
Moon-Hyoung
MH
Lee
Boyoung
B
Joung
D000328:Adult; D001282:Atrial Flutter / Q000150:complications / Q000175:diagnosis*; D002921:Cicatrix / Q000150:complications* / Q000175:diagnosis*; D003937:Diagnosis, Differential; D004562:Electrocardiography / Q000379:methods; D006330:Heart Defects, Congenital / Q000150:complications* / Q000175:diagnosis*; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000209:etiology*