PACs and PVCs are "extra" heartbeats that start from somewhere other than the heart's normal pacemaker — they're extremely common, usually harmless, and often felt as a skipped beat or a flutter. In most people they need nothing more than reassurance, though a high burden of them, or ones occurring alongside other findings, can sometimes warrant closer evaluation.
What Are PACs and PVCs?
- PAC (premature atrial contraction) — an early, extra beat that starts in the atria (the heart's upper chambers), instead of from the heart's normal pacemaker
- PVC (premature ventricular contraction) — an early, extra beat that starts in the ventricles (the heart's lower, main pumping chambers)
Both interrupt the heart's normal rhythm briefly, which is often what you actually feel — not necessarily the extra beat itself, but the slightly longer pause and stronger beat that follows it.
What's Happening in Your Heart
A cell somewhere outside the heart's normal pacemaker (the sinus node) fires early, triggering a beat out of the usual sequence. This is a common, usually benign electrical quirk — nearly everyone has occasional PACs or PVCs, often without ever noticing them.
Types & Causes
- Common triggers — caffeine, alcohol, stress, poor sleep, dehydration, and certain stimulant medications or supplements
- Often no trigger is identified at all, particularly for occasional, isolated ones
- A high burden of PVCs specifically (a large percentage of total heartbeats over 24 hours) is the feature that sometimes prompts closer evaluation, since a very high burden over time can, in some people, affect heart function — a condition sometimes called PVC-induced cardiomyopathy when the burden is high enough and sustained enough
- Occurring alongside underlying heart disease changes how these are interpreted — the same PVC pattern means something different in an otherwise healthy heart versus a weakened one
Common Symptoms
A sensation of a skipped beat, a flutter, a thud, or a brief "flip-flop" feeling in the chest — often more noticeable when resting quietly (like lying in bed) than during activity. Many people have PACs or PVCs with no symptoms at all, found only on a routine ECG or monitor.
How It's Diagnosed
An ECG can catch one if it happens to occur during the recording. Because these are often intermittent, a Holter monitor or extended patch monitor is frequently used to capture how often they occur and calculate your specific burden. An echocardiogram is often obtained, especially with a high PVC burden, to check that heart structure and function are normal. (See Cardiac Testing & Imaging.)
Main Treatment Options
For occasional, low-burden PACs/PVCs in an otherwise healthy heart, often no treatment beyond addressing identifiable triggers (caffeine, alcohol, stress, sleep) and reassurance. For bothersome symptoms or a higher burden, beta-blockers are often the first medication tried. For a high, persistent PVC burden — particularly if it's affecting heart function or causing significant symptoms — catheter ablation targeting the specific site of origin is a highly effective option, and can sometimes improve heart function that had declined due to the PVC burden itself.
Lifestyle Changes That Help
- Identifying and moderating your personal triggers — caffeine, alcohol, and poor sleep are the most common
- Stress management techniques, since stress and anxiety are common amplifiers of how noticeable these feel
- Staying well hydrated and maintaining consistent electrolyte levels
Living With It
For the great majority of people, these are a benign, lifelong quirk that doesn't need active treatment beyond reassurance and, sometimes, trigger management. If your care team has checked your heart structure and function and found them normal, that reassurance is genuinely meaningful — you can generally trust it rather than continuing to worry with each noticed skip.
When to Call Your Doctor vs. Go to the ER
- New or increasing frequency of skipped beats or palpitations that concern you
- Palpitations with fainting, chest pain, or severe shortness of breath — these need urgent evaluation to rule out a more serious rhythm problem
Common Questions
Are these dangerous?
For most people, no — in a structurally normal heart, occasional PACs and PVCs are considered a benign finding, though your care team will individualize this based on your specific burden and heart health.
Why do I feel them more at night?
Fewer distractions and a quieter body make you more likely to notice normal cardiac sensations you'd otherwise tune out during activity — it's usually about awareness, not that they happen more often at night.
Do I need to stop drinking coffee?
Not necessarily, but if you notice a clear pattern between caffeine and your symptoms, moderating your intake is a reasonable, low-risk first step to try.
What counts as a 'high burden' of PVCs?
There's no single universal cutoff, but burdens in the range of roughly 10-15% or more of total heartbeats over 24 hours are generally when closer monitoring of heart function becomes more of a focus — your care team will interpret your specific number in the context of your symptoms and heart function.
Can PVCs themselves weaken my heart?
A genuinely very high burden, sustained over a long period, can occasionally lead to a reversible weakening of heart function called PVC-induced cardiomyopathy — uncommon, but part of why very frequent PVCs get monitored rather than dismissed automatically as harmless.