Electrophysiological Follow-Up of Tetralogy of Fallot

Abstract

Arrhythmias and sudden death are well-recognized complications that occur late after correction of tetralogy of Fallot. This study, based on the literature and personal work, reviews the numerous investigations prompted by these complications and provides recommendations regarding follow-up. Conduction disturbances and ventricular arrhythmias are both common; although mostly asymptomatic, they are the likely cause of syncopy and sudden death. Supraventricular arrhythmias are less common but cause symptoms more frequently. Detecting patients at risk for life-threatening arrhythmias is an important task. The simple surface electrocardiogram (ECG) gives a host of information regarding patients at risk. Holter recordings, signal-averaged ECG, and invasive electrophysiological studies may all be helpful; the indications to perform these investigations are discussed and propositions are made for the follow-up of the postoperative patient. There is hope that a systematic approach along these lines, together with surgery done at an earlier age, will decrease the incidence of severe arrhythmias and sudden death in the future.

Risk factors for arrhythmia and late death in patients with right ventricle to pulmonary artery conduit repair—Japanese multicenter study

“…Data from TOF after repair suggest that asymptomatic Holter arrhythmia is not predictive of sudden cardiac death and we submit that most significant arrhythmias could be detected and reported here by 12 lead electrocardiograms and/or exercise testing and/or 24 h Holter monitoring [27,28]. Lack of right ventricular volumetric data and precise quantification of pulmonary regurgitation limits the ability of this study to conclude on the role of the latter.…”

Role of invasive and noninvasive testing in risk stratification of sudden cardiac death in children and young adults: an electrophysiologic perspective

“…After TOF repair, induced VT correlates well with clinical sustained VT; programmed ventricular stimulation also guides drug therapy for clinical VT. EPS does not identify patients who are at risk of sudden death, however [110,111]. This probably is true in other congenital heart diseases postrepair [112].…”

The impact of pulmonary valve replacement after tetralogy of Fallot repair: a matched comparison

“…Murphy et al [2] and Silka et al [1] reported a 6% prevalence of late sudden cardiac death among patients with up to 30 years of follow-up. Important ventricular and atrial arrhythmias are also prevalent, occurring in up to 35% of patients [3][4][5]; Harrison et al [4] and Gatzoulis et al [6] reported risk factors for ventricular arrhythmia and sudden death, including repair at an older age, previous transannular patch repair, severe pulmonary regurgitation, right ventricular (RV) dilatation and dysfunction, RV outflow tract aneurysm, left ventricular (LV) systolic dysfunction, QRS duration !180 ms and increased QRS duration rate of change during follow-up [3]. A recent study showed that pulmonary regurgitation was the predominant lesion associated with ventricular tachycardia and sudden death [6].…”