Consequently, this pilot study was performed to elaborate the potential role of soluble HSP70 (HSPA1A) [16] and anti-HSP70 antibodies in the AF development by (1) comparing plasma levels of patients with paroxysmal and persistent AF with AF-free controls and (2) by evaluating their response to catheter ablation that generates myocardial injury and their possible association with rhythm outcome. Here, HSPA1A is linked to atrial fibrillation.