Rhythm and conduction abnormalities after surgical correction of Fallot’s Tetralogy

Objectives: Rhythm and conduction disturbances are common findings after surgical correction of Tetralogy of Fallot. Methods:71 Tetralogy of Fallot patients underwent surgical correction in Heart Institute, Cluj Napoca, Romania, between September 2001 and July 2006, without prior palliations. Employed surgical techniques were: transannular patch (n=46), infundibular patch (n=12), infundibular patch + pulmonary patch (n=5), transatrial + transpulmonary repair (n=8). The patients were divided into 2 groups, correction under 1 year of age and correction above 1 year of age, for comparative study of results. Among the 71 patients group, 58 were followed up at 43 months meaninterval in group 1, and 48 months mean interval in group 2, by standard electrocardiography, 24 hours Holter monitoring and echocardiography. Results: Major differences between the two groups were recorded: the QRS complex and Q-T corrected interval (QTc) duration were significantly different between the 2 groups, right bundle branch block with left anterior hemiblock was noticed especially in patients operated over 1 year of age, ventricular arrhythmias were present especially in the same group of patients operated over 1 year and did not appear in patients with combined (transatrial and transpulmonary) repair; furthermore, ventricular arrhythmias were especially present in patients with postoperative severe pulmonary regurgitation; the mean QRS duration was intensely significant correlated with the type of arrhythmia. Conclusions: Rhythm and conduction disturbances are statistically significant correlated with the age at correction (the grater the age at operation, the bigger the risk for this type of complications), moreover being correlated with the surgical technique as well, and the postoperative pulmonary regurgitation is a key factor for rhythm disorders.