Exploring the cause of conduction delays in patients with repaired Tetralogy of Fallot.
Europace
; 23(23 Suppl 1): i105-i112, 2021 03 04.
Article
em En
| MEDLINE
| ID: mdl-33751080
ABSTRACT
AIMS:
Cardiac dyssynchrony in patients with repaired Tetralogy of Fallot (rToF) has been attributed to right bundle branch block (RBBB), fibrosis and/or the patches that are inserted during repair surgery. We aimed to investigate the basis of abnormal activation in rToF patients by mapping the electrical activation sequence during sinus rhythm (SR) and right ventricular (RV) pacing. METHODS ANDRESULTS:
A total of 17 patients were studied [13 with rToF, 2 with left bundle branch block (LBBB), and 2 without RBBB or LBBB (non-BBB)] during medically indicated cardiac surgery. During SR and RV pacing, measurements were performed using 112-electrode RV endocardial balloons (rToF only) and biventricular epicardial sock arrays (four of the rToF and all non-rToF patients). During SR, functional lines of block occurred in five rToF patients, while RV pacing caused functional blocks in four rToF patients. The line of block persisted during both SR and RV pacing in only 2 out of 13 rToF patients. Compared to SR, RV pacing increased dispersion of septal activation, but not dispersion of endocardial and epicardial activation of the RV free wall. During pacing, RV and left ventricular activation dispersion in rToF patients were comparable to that of the non-rToF patients.CONCLUSION:
The results of the present study indicate that the delayed activation in the right ventricle of rToF patients is predominantly due to block(s) in the Purkinje system and that conduction in RV tissue is fairly normal.Palavras-chave
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Tetralogia de Fallot
Tipo de estudo:
Diagnostic_studies
/
Etiology_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article