Serum levels of interleukin-2 predict the recurrence of atrial fibrillation after pulmonary vein ablation.
OBJECTIVE
Interleukin-2 has a significant antitumor activity in some types of cancer, and has been associated with the development of atrial fibrillation (AF). In addition, IL-2 serum levels in recent onset AF have been related with pharmaceutical cardioversion outcomes. We evaluated the hypothesis that a relationship exists between inflammation and the outcome of catheter ablation of AF.


METHODS
We studied 44 patients with paroxysmal AF who underwent catheter ablation. Patients with structural heart disease, coronary artery or valve disease, active inflammatory disease, known or suspected neoplasm, endocrinopathies, or exposure to anti-inflammatory drugs were excluded. All study participants underwent evaluation with a standardized protocol, including echocardiography, and cytokine levels of interleukin-2, interleukin-4, interleukin-6, interleukin-10, tumour necrosis factor-alpha, and gamma-interferon determination before procedure. Clinical and electrocardiographic follow-up were performed with Holter-ECG at 3, 6 and 12months in order to know if sinus rhythm was maintained.


RESULTS
After catheter ablation of the 44 patients included (53±10years, 27.3% female), all patients returned to sinus rhythm. During the first year of follow-up seven patients (15.9%) experienced recurrence of AF. The demographics, clinical and echocardiographic features, and pharmacological treatments of these patients were similar to those who maintained sinus rhythm. The only independent factor predictive of recurrence of AF was an elevated level of IL-2 (OR 1.18, 95% CI 1.12-1.38).


CONCLUSIONS
High serum levels of interleukin-2, a pro-inflammatory non-vascular cytokine, are associated with the recurrence of AF in patients undergoing catheter ablation.
UGC del Corazón, Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Victoria de Málaga, IMIBA (Instituto de Investigación Biomédica de Málaga), Universidad de Málaga, Spain. Electronic address: fjcabrera@secardiologia.es.
Fernando
F
Cabrera-Bueno
UGC del Corazón, Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Victoria de Málaga, IMIBA (Instituto de Investigación Biomédica de Málaga), Universidad de Málaga, Spain.
Carmen
C
Medina-Palomo
UGC del Corazón, Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Victoria de Málaga, IMIBA (Instituto de Investigación Biomédica de Málaga), Universidad de Málaga, Spain.
Amalio
A
Ruiz-Salas
UGC del Corazón, Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Victoria de Málaga, IMIBA (Instituto de Investigación Biomédica de Málaga), Universidad de Málaga, Spain.
Ana
A
Flores
UGC del Corazón, Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Victoria de Málaga, IMIBA (Instituto de Investigación Biomédica de Málaga), Universidad de Málaga, Spain.
Noela
N
Rodríguez-Losada
UGC del Corazón, Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Victoria de Málaga, IMIBA (Instituto de Investigación Biomédica de Málaga), Universidad de Málaga, Spain.
Alberto
A
Barrera
UGC del Corazón, Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Victoria de Málaga, IMIBA (Instituto de Investigación Biomédica de Málaga), Universidad de Málaga, Spain.
Manuel
M
Jiménez-Navarro
UGC del Corazón, Servicio de Cardiología, Hospital Clínico Universitario Virgen de la Victoria de Málaga, IMIBA (Instituto de Investigación Biomédica de Málaga), Universidad de Málaga, Spain.
Javier
J
Alzueta
D001281:Atrial Fibrillation / Q000097:blood* / Q000000981:diagnostic imaging / Q000209:etiology*; D016022:Case-Control Studies; D017115:Catheter Ablation / Q000009:adverse effects*; D003710:Demography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007376:Interleukin-2 / Q000097:blood*; D057230:Limit of Detection; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*; D012008:Recurrence; D014463:Ultrasonography
D007376:Interleukin-2
Atrial fibrillation; Catheter ablation; Cytokine; Inflammation; Interleukin 2