<h4>Background</h4>Titin (TTN), a giant structural and signaling protein of striated muscle, participates in intracellular signaling networks and cytoskeletal organization, potentially influencing cell activation, trafficking, and interactions with other tissues, including the heart.<h4>Methods</h4>In this pilot study, 29 patients with acute myocarditis and 10 healthy individuals were prospectively enrolled. Here, TTN is linked to myocarditis.