Ablation of atrial tachyarrhythmias late after surgical repair of tetralogy of Fallot.
BACKGROUND
Patients with repaired tetralogy of Fallot may develop symptomatic and haemodynamic deterioration for many reasons such as arrhythmia, pulmonary regurgitation, and impairment in ventricular function. We describe a consecutive group of patients whose main clinical problem was atrial tachyarrhythmias.


OBJECTIVE
To describe the clinical outcome of atrial tachyarrhythmias occurring late after surgical repair of tetralogy of Fallot; to define the circuits/foci responsible for these atrial tachyarrhythmias; to evaluate the outcome of computer-assisted mapping and catheter ablation in this patient group.


RESULTS
Consecutive patients with surgically repaired tetralogy of Fallot and atrial tachyarrhythmias, who underwent catheter ablation between January, 2001 and June, 2007, were identified retrospectively from case records. Computer-assisted mapping was performed in all using either EnSite® (St Jude Medical Inc.) arrhythmia mapping and intra-cardiac catheter guidance system or CARTO™ (Biosense Webster Inc.) electroanatomical mapping systems. Ten patients (four males) with a median age of 39 plus or minus 8 years were studied. The total number of atrial tachyarrhythmias identified was 22 (six macro-reentrant, 16 micro-reentrant/focal). In nine patients, catheter ablation led to improvement in arrhythmia episodes and/or symptoms during follow-up of 41 plus or minus 20 months. Following ablation(s), five patients required pacing for pre-existing conduction disease and five needed further surgery for haemodynamic indications. All patients remained on anti-arrhythmic drugs.


CONCLUSIONS
Patients with surgically repaired tetralogy of Fallot and atrial tachyarrhythmias typically have multiple arrhythmic circuits/foci arising from a scarred right atrium. Catheter ablation reduces arrhythmia frequency and improves symptoms. However, hybrid management is often required, comprising drugs, pacing, and further surgery tailored to the individual.
Department of Adult, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, United Kingdom.
Dan
D
Raine
John
J
O'Sullivan
Milind
M
Chaudhari
Leslie
L
Hamilton
Asif
A
Hasan
John P
JP
Bourke
D000328:Adult; D018780:Body Surface Potential Mapping; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D013612:Tachycardia, Ectopic Atrial / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D013771:Tetralogy of Fallot / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult