Association of post-cardioversion transcardiac concentration gradient of soluble tumor necrosis factor-related apoptosis-inducing ligand (sTRAIL) and inflammatory biomarkers to atrial fibrillation recurrence

► This study describes the existence of a transcardiac sTRAIL concentration gradient. ► This concentration gradient implies that sTRAIL is indeed produced by the heart. ► sTRAIL gradient is inversely related to AFib recurrence after cardioversion. ► The study suggests a protective role of sTRAIL in AFib substrate-altering processes.