ELI5: Why does coughing stop/subdue heart palpitations? I've been researching this to try and find an answer but haven't been able to find anything that really explains it. When I feel the "flutter" in my chest I usually find that a slight cough will stop it, though the flutter itself somewhat provokes the cough. The same goes for whenever my heart is beating really hard. Not beating fast, just harder than usual. 