Circulating Soluble Suppression of Tumorigenicity 2 Robust Predictor of Recurrence in Atrial Fibrillation

In persistent atrial fibrillation (AFib) patients, increased soluble suppression of tumorigenicity 2 (sST2) is a strong marker of recurrence after radiofrequency ablation, according to a study published in Frontiers in Cardiovascular Medicine. 

In this study, researchers analyzed baseline plasma levels of sST2 from 210 patients with persistent AFib (n = 117) and paroxysmal AFib (n = 93) patients. The population were followed up for 15 months after ablation. The researchers used multivariable Cox regression relationship between circulating sST2 and recurrence was assessed by multivariable Cox regression, while cutoff values of sST2 were determined using operating characteristic curve. To assess the relationship between baseline sST2 level and left atrial volume index (LAVI), the investigative team used multivariate linear regression analysis. They conducted sST2 measurements at 24 hours, 6 months, and 15 months of ablation.

According to the results of the study, sST2 was linked with with left atrial volume index (LAVI) in the persistent AFib group, and elevated sST2  was observed to independently increased the risk of recurrence of AFib when adjusted for co-variables. In contrast, elevated sST2 cannot predict recurrence in paroxysmal AFib, the researchers noted.

The study did have several limitations. First, the study was only carried out in one center, and with a relatively small cohort. Second, the researchers noted, the IHC and WB experiments were done on left atrial appendages taken from patients presenting with a different pathology (AFib combined with valvular heart disease). Third, they further noted, is no direct assessment of atrial fibrosis by using MRI.

 

“In persistent AFib, circulating sST2 ≥ 39.25 ng/ml was predictive of recurrence after primary ablation. Furthermore, atrial myofibroblasts were likely a cellular source of circulating sST2, which might serve as an important biomarker for the degree atrial fibrosis. Inhibiting circulating sST2 might be useful as an adjuvant treatment to improve outcomes of catheter ablation for persistent AFib,” the researchers concluded.