Author`s Reply.

To the Editor,

First, we would like to thank you for your interest in our paper entitled “Prognostic role of soluble suppression of tumorigenicity-2 on cardiovascular mortality in outpatients with heart failure” (1).

We had pointed out in the paper that soluble suppression of tumorigenicity-2 (sST2) levels increased in collagen tissue diseases, cancer, sepsis, and ulcerative colitis, indicating that it is also associated with inflammation and immunological processes (2). However, cancer, sepsis, and ongoing systemic inflammatory conditions including autoimmune diseases were among our exclusion criteria, although our patients were HF outpatients and inflammatory markers such as CRP levels were not routinely tested.

The association between sST2 level and the functional capacity of patients with chronic heart failure had been previously evaluated in a smaller case-control study from our cohort with an available double-checked NYHA Class data, although survival data had not been considered (3). We herein reiterate the results designating that sST2 levels were higher in patients with NYHA functional classes III and IV than in patients with NYHA functional classes I and II (p<0.001). However, we also declare that in both of our works, body mass index and heart rate were not thoroughly considered and that these chronic HF outpatients were well-treated with beta blockers, and the relation between ST2 level and heart rate is not well-validated in the presence of chronic beta blocker therapy.