Magnetic navigation in adults with atrial isomerism (heterotaxy syndrome) and supraventricular arrhythmias.
OBJECTIVE
We analysed the type and mechanism of supraventricular arrhythmias encountered in a series of symptomatic adults with atrial isomerism undergoing catheter ablation procedures.


RESULTS
The study population included consecutive adults with atrial isomerism who had previously undergone surgical repair or palliation of the associated anomalies. Patients underwent electrophysiological study for symptomatic arrhythmia in our institution between 2010 and 2012 using magnetic navigation in conjunction with CARTO RMT and three-dimensional (3D) image integration. Eight patients (five females) with a median age of 33 years [interquartile range (IQR) 24-39] were studied. Access to the cardiac chambers of interest was obtained retrogradely via the aorta using remotely navigated magnetic catheters in six patients. Radiofrequency ablation successfully targeted twin atrioventricular (AV) nodal reentrant tachycardia in two patients, atrial fibrillation (AF) in three, focal atrial tachycardia (AT) mainly originating in the left-sided atrium in four patients, and macro-reentrant AT dependent on a right-sided inferior isthmus in three patients. The median fluoroscopy time was 3.0 min (IQR 2-11). After a median follow-up of 10 months (IQR 6-21), five of the ablated patients are free from arrhythmia; two patients experienced episodes of self-terminated AF and AT, respectively, within one month post-ablation; the remaining patient had only non-sustained AT during the electrophysiological study and was managed medically.


CONCLUSIONS
Various supraventricular tachycardia mechanisms are possible in adults with heterotaxy syndrome, all potentially amenable to radiofrequency ablation. The use of remote magnetic navigation along with 3D mapping facilitated the procedures and resulted in a short radiation time.
Department of Cardiology, Royal Brompton and Harefield NHS Foundation Trust, London, SW3 6NP, UK. irina.horduna@gmail.com
Irina
I
Suman-Horduna
Sonya V
SV
Babu-Narayan
Akiko
A
Ueda
Lilian
L
Mantziari
Marko
M
Gujic
Procolo
P
Marchese
Konstantinos
K
Dimopoulos
Michael A
MA
Gatzoulis
Michael L
ML
Rigby
Siew Yen
SY
Ho
Sabine
S
Ernst
D000328:Adult; D018780:Body Surface Potential Mapping / Q000379:methods*; D005260:Female; D059446:Heterotaxy Syndrome / Q000175:diagnosis* / Q000601:surgery*; D006801:Humans; D008280:Magnetics / Q000379:methods*; D008297:Male; D025321:Surgery, Computer-Assisted / Q000379:methods*; D013617:Tachycardia, Supraventricular / Q000175:diagnosis* / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult
Adult congenital heart disease; Atrial isomerism; Heterotaxy; Remote magnetic navigation; Supraventricular arrhythmia; Twin AV nodes