Ventricular arrhythmia in unrepaired and repaired tetralogy of Fallot. Relation to age, timing of repair, and haemodynamic status

Ventricular arrhythmias are common after repair of tetralogy of Fallot and are associated with late sudden death. This study examined the relation of ventricular arrhythmia during normal daily activities to the timing of repair, duration of follow up, and postoperative haemodynamic status. Forty eight hour ambulatory electrocardiographic monitoring was performed in 145 patients: 60 (aged 3 months to 46 years) had not yet undergone repair and 85 were followed from four to 22 (mean 14.6) years after repair. Cardiac catheterisation was performed in 47 (55%) one to 22 (mean 8.9) years after repair. Twelve (20%) of the uncorrected group had ventricular arrhythmia. The incidence increased significantly with age from 0% in patients aged