Coexistence of tachyarrhythmias in patients with tetralogy of Fallot.

BACKGROUND: The expanding population of adult patients with tetralogy of Fallot (ToF) requires knowledge of its long-term sequelae.

OBJECTIVE: The purpose of this study was to examine the coexistence and order of appearance of atrial fibrillation (AF), other supraventricular tachycardias (SVTs), ventricular tachycardia (VT), and ventricular fibrillation (VF), and their impact on survival during long-term follow-up.

METHODS: Adult, corrected ToF patients [N = 225; 128 male; mean ± SD (minimum-maximum) age 41 ± 12 (19-79) years] were included in the study. Medical correspondence, ECGs, and Holter recordings were reviewed for documented AF, other SVTs, VT, and VF.

RESULTS: During follow-up of 35 ± 9 (16-64) years, sustained tachyarrhythmias, including SVT (n=50, 22%), AF (n=29, 13%), VT (n=20, 9%), and VF (n=9, 4%), were observed in 71 patients (32%), of whom 27 (38%) had coexistence of different tachyarrhythmias. In 18 patients with coexisting SVT and AF, SVT most often preceded AF in 13 (72%). Age at SVT onset was similar between those with and those without subsequent AF development (40 ± 17 years vs 35 ± 16 years; P = .283). However, age at SVT and AF onset were positively correlated (rho 0.585; P = .011). Prevalence of SVT/AF was associated with VT/VF prevalence (odds ratio [OR] 4.59; P < .001). Although 11% of patients with SVT/AF subsequently develop VT/VF, onset of SVT/AF could not predict future VT/VF development (OR 1.81; P = .233). Adult ToF patients are initially at risk for SVT development, followed by AF, VT, and VF at 46 (43-50), 56 (53-59), 57 (54-61), and 62 (61-63) years after ToF correction (P < .001), respectively. Survival time decreased when sustained tachyarrhythmias developed (P = .024). Age at onset of SVT, AF, and VT was positively correlated with age at death (SVT: rho 0.734; P = .004; AF: rho 0.783; P = .007, VT: rho 0.755; P = .050).

CONCLUSION: Coexistence of different (supra)ventricular tachyarrhythmias is frequently observed in adult ToF patients. In these patients, a specific order of these tachyarrhythmias was observed. Tachyarrhythmias are associated with decreased survival time, and, more importantly, age at tachyarrhythmia development positively correlates with age at death.