Late clinical and functional assessment of arrhythmias in children after repair of Tetralogy of Fallot.
BACKGROUND
Cardiac arrhythmias are the major cause of late sudden death in patients undergoing repair of Tetralogy of Fallot (TF).


OBJECTIVE
To evaluate the occurrence of cardiac arrhythmias in children and adolescents undergoing repair of TF, and to associate them with clinical aspects and laboratory tests.


METHODS
Cross-sectional study of 37 patients undergoing repair of TF at Instituto Estadual de Cardiologia Aloysio de Castro (Rio de Janeiro). After review of the medical records and clinical assessment, the patients underwent electrocardiography (ECG), echocardiography (Echo), 24-h Holter monitoring and exercise test (ET), whose results were subjected to statistical analysis.


RESULTS
A total of 37 patients of whom 54% were males with a mean age of 9.7 ± 3.5 years and mean follow-up period of 4.7 ± 1.9 years were studied. The abnormalities most frequently found were: on ECG: right bundle branch block (89%); Echo: severe pulmonary regurgitation (43%), mild pulmonary stenosis (73%), moderate right ventricular hypertrophy (RVH, 57%); on ET: low exercise capacity (90%), impaired chronotropic response (40%), arrhythmias (20%); on Holter monitoring: arrhythmias (59%, of which 44% were ventricular, 38% supraventricular, and 24% both ventricular and supraventricular, with predominance of infrequent and benign ventricular premature beats). Five patients (15%) presented with multiform ventricular premature beats. There was an association of ventricular arrhythmia with moderate and severe RVH (p=0.026), as well as with right ventricle-to-pulmonary artery gradient (RV/PA) > 45 mmHg (p=0.004). The logistic regression analysis showed that increased RV/PA gradient was an independent predictor of ventricular arrhythmia (p=0.017).


CONCLUSIONS
Cardiac arrhythmia was a common finding in a large proportion of children and adolescents after surgical repair of TF; however, it was infrequent and benign in most of the cases. The RV/PA gradient was considered a strong predictor of ventricular arrhythmia.
Pfeiffer
Maria Eulália Thebit
ME
Instituto Estadual de Cardiologia Aloysio de Castro, Rio de Janeiro, RJ, Brazil. methebit@cardiol.br
Andrea
Eduardo Machado
EM
Serra
Salvador Manoel
SM
Assumpção
Claudio Roberto
CR
Herdy
Gesmar Volga Haddad
GV
D000293:Adolescent; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000209:etiology; D002648:Child; D004562:Electrocardiography; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D011183:Postoperative Complications / Q000175:diagnosis*; D013771:Tetralogy of Fallot / Q000601:surgery*; D016896:Treatment Outcome