palpitations
Palpitations are the unsettling awareness of your own heartbeat — feeling it pound, race, flutter, skip, or thud when normally you notice nothing at all. Most of the time the heart works silently in the background, like a clock you stop hearing; palpitations are the moments when that ticking suddenly becomes loud and impossible to ignore.
They can arise from a heart that is simply beating fast for a good reason — exercise, fever, fright, caffeine — or from a true rhythm disturbance, an arrhythmia, in which extra, missing, or chaotic beats break the smooth cadence. A common harmless example is a premature beat: the early beat is faint and the pause after it lets the next beat fill more, producing a forceful thump that people describe as a skip or flip. Anxiety and an overactive thyroid are also frequent triggers.
Because palpitations span the trivial and the serious, the key questions are whether they are regular or irregular, fast or slow, and whether they come with fainting, chest pain, or breathlessness. Capturing the rhythm during an episode — with an electrocardiogram or a wearable monitor — is the most reliable way to tell a benign flutter from a dangerous arrhythmia, since the heart often behaves normally by the time of the appointment.
A young office worker feels her heart suddenly race and pound for several minutes during a stressful meeting, then stop just as abruptly — a pattern that prompts a wearable monitor to catch the rhythm.
Sudden onset and offset of a fast heartbeat hints at a paroxysmal arrhythmia worth recording.
Palpitations accompanied by fainting, prolonged chest pain, or severe breathlessness are more concerning and deserve prompt evaluation; isolated brief skips in an otherwise healthy person are usually benign.