The 'In a Heartbeat' meme, often depicted as a medical EKG monitor or heart rate graph, visually illustrates how specific stimuli cause a sudden surge in excitement or anxiety. The template typically shows a steady, rhythmic line that abruptly transforms into a chaotic, rapid spike when the subject encounters a particular person, hobby, or stressful situation. While it began as a simple drawing on social media platforms like Twitter and Tumblr, it evolved into various digital formats used to humorously express intense passion or fear. It is a staple for fandoms and hobbyists to showcase their dedication to a specific interest through visual exaggeration.