Optimal timing of the Fontan conversion: Change in the P-wave characteristics precedes the onset of atrial tachyarrhythmias in patients with atriopulmonary connection

Abstract

Objectives: Atrial tachyarrhythmia is a common complication late after the atriopulmonary connection Fontan procedure. The P-wave duration and dispersion have been regarded as useful markers for its prediction. The purpose of this study was to analyze change in the P-wave characteristics over time after the atriopulmonary connection Fontan procedure, with a special emphasis on the timing of the Fontan conversion. Methods: We reviewed clinical and electrocardiographic data in 18 patients with classic tricuspid atresia who underwent the atriopulmonary connection Fontan procedure. Their median age at operation was 4.1 years (range, 1.1-22 years), and the median follow-up period was 18.1 years (range, 10-25 years). We measured the P-wave duration, dispersion, and axis from consecutive 12-lead electrocardiograms in each patient. Results: There was a significant increase in the maximum P-wave duration as well as the P-wave dispersion over time. Transient ectopic atrial rhythm was observed in 16 patients during follow-up. Atrial tachyarrhythmia developed subsequent to transient ectopic atrial rhythm in 8 patients. Ten patients underwent the conversion. Atrial tachyarrhythmia recurred in 2 patients who had sustained arrhythmia (6.0 and 8.0 years) before the conversion. In contrast, the other 8 patients with transient ectopic atrial rhythm alone or nonsustained atrial tachyarrhythmia have been free from arrhythmia after the conversion. Conclusions: Patients commonly and increasingly had prolonged P-wave duration, larger P-wave dispersion, and ectopic atrial rhythm, along with an atrial tachyarrhythmia propensity, late after the atriopulmonary connection Fontan procedure. These P-wave characteristics were informative when considering the Fontan conversion before a sustained atrial tachyarrhythmia ensued. © 2007 The American Association for Thoracic Surgery.