Transforming Growth Factor-β1 Level and Outcome After Catheter Ablation for Nonparoxysmal Atrial Fibrillation

Study Questions:

Are plasma levels of transforming growth factor-β1 (TGF-β1), which induces cardiac fibrosis, associated with the results of radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF)?

Methods:

The plasma TGF-β1 level was measured before RFCA in 154 patients with paroxysmal AF and 46 patients with persistent or permanent AF (mean age 54 years). Serial Holter monitors or event monitors were used to assess efficacy during a mean follow-up of 10.9 months. A post-ablation AF recurrence was defined as AF lasting >1 minute after a 3-month blanking period.

Results:

AF recurred in 37% of patients with paroxysmal AF, with no relationship between TGF-β1 level and recurrent AF. AF recurred in 65% of the patients with nonparoxysmal AF, and the TGF-β1 level was significantly higher among the patients with (34.6 ng/ml) than without (27.3 ng/ml) recurrent AF. By multivariate analysis, the only independent predictors of recurrent AF were TGF-β1 level and left atrial diameter (LAD). The AF recurrence rate was 89% in patients with LAD >43 mm and TGF-β1 level >31.3 ng/ml compared to 11% in patients with LAD ≤43 mm and TGF-β1 level ≤31.3 ng/ml.

Conclusions:

The TGF-β1 level is an independent predictor of recurrent AF after RFCA of nonparoxysmal AF.

Perspective:

The results of experimental and clinical studies have implicated TGF-β1 in the pathogenesis of atrial fibrosis. The authors concluded that the preablation TGF-β1 level can help to identify patients most likely to benefit from RFCA of nonparoxysmal AF. However, the study did not present data on the results of redo procedures. Therefore, whether TGF-β1 levels predict the ultimate outcome of RFCA of persistent or permanent AF after repeat procedures is unclear.

Keywords: Recurrence, Follow-Up Studies, Biomarkers, Transforming Growth Factor beta1, Atrial Fibrillation, Electrocardiography, Heart Rate, Catheter Ablation, Fibrosis


< Back to Listings