Impact of Junctional Ectopic Tachycardia after Repair of Tetralogy of Fallot (TOF)

Objectives: Junctional ectopic tachycardia (JET) is a common arrhythmia after surgical repair of tetralogy of Fallot and poses a severe threat in the initial postoperative period due to the resulting hemodynamic impairment. However, little is known about the long-term consequences and if the occurrence of JET predisposes to subsequent arrhythmias.

Methods: From 2003 to 2012, a total of 105 patients (median age: 5.2; range: 0.2–65.6 months) underwent repair of tetralogy of Fallot at our institution. 14 of them developed JET, all within the first 24 hours after surgery. In this retrospective study, we examined surgical and electrocardiographic data over a mean follow-up period of 3.8 years (range: 7 days to 12.5 years), to detect risk factors for the incidence of JET and to evaluate the outcome of these patients.

Results: JET lasted over a mean time of 3.1 (range: 1–7 days) with a rate of 202 (range: 170–225/min), showing return to normal sinus rhythm after 4.9 (range 1–11 days). Only 4 of the 14 patients went straight from sinus rhythm to JET. The others either presented a transient AV block (5 patients) or junctional rhythm (5 patients), 8 of them immediately after leaving the cardiopulmonary bypass, showing a significant relation (p = 0.010). Other associations with JET were young age (p = 0.025) - with a median age of 3.2 (range 0.5–8.2 months) - and longer bypass time (p = 0.044) - with a median time of 143 (range 62–238 minute). Unrelated factors were body weight (p = 0.123), gender (p = 0.766) and hypoxic spells in the anamnesis (p = 1.000). The incidence of JET was linked to a longer stay at the ICU (p = 0.000) and a prolonged need for catecholamines (p = 0.005). Of the 105 patients, only 1 died within the first month after surgery (ECMO therapy was terminated after a cerebral embolism), with the occurrence of JET over 7 days factoring into his postoperative course. Of the 13 surviving JET patients, 11 continued to have a normal sinus rhythm over the follow-up period, while 2 developed an AV block-I. All 13 patients were NYHA-I at their last follow-up and showed no significant difference in QRS-duration (p = 0.579), compared with the rest of the patient base.

Conclusion: JET remains a potential fatal complication in the initial postoperative period. Risk factors are young age, longer bypass time and an intraoperative AV block or junctional rhythm. However, apart from the possibility of inducing an AV block-I, it does not cause a susceptibility to subsequent arrhythmias.

No conflict of interest has been declared by the author(s).