Skipping a beat — the surprise of palpitations

Sometimes you may notice that your heart has unexpectedly started to race or pound, or feels like it has skipped a beat. These sensations are called palpitations. For most people, palpitations are a once-in-a-blue-moon occurrence. Others have dozens a day, some so strong that they feel like a heart attack.

Most palpitations are caused by a harmless hiccup in the heart's rhythm. A few reflect a problem in the heart or elsewhere in the body. Doctors can be quick to attribute them to anxiety, depression, or some other emotional or psychological problem. Although sometimes that's exactly right, it's important to first rule out harmful heart rhythms and other physical causes.

A palpitation primer

Palpitations are extremely common. Different people experience palpitations in different ways. You might feel as though your heart is fluttering, throbbing, flip-flopping, or pounding, or that it has skipped a beat. Some people feel palpitations as a pounding in the neck; others as a general sense of unease.

Some palpitations appear out of the blue and disappear just as suddenly. Others are linked with certain activities, events, or feelings. Exercise and physical activity can generate palpitations, as can anxiety or stress. Some people notice palpitations when they are drifting off to sleep; others, when they stand up after bending over.

Triggering palpitations

Many things can generate palpitations. These include:

  • Stress, anxiety, or panic
  • Dehydration
  • Low potassium
  • Low blood sugar
  • Too much caffeine, chocolate, or alcohol
  • Nicotine
  • Exercise
  • Standing up
  • Swallowing
  • Fever
  • Prior heart attack
  • Mitral valve prolapse
  • Anemia
  • Overactive thyroid
  • Pregnancy
  • Menopause
  • Acid reflux (heartburn)
  • Drugs and medications such as cocaine, amphetamines, diet pills, some cough and cold remedies, some antibiotics, thyroid hormone, digoxin, asthma medications, beta blockers, or anti-arrhythmics
  • Dietary supplements such as ephedra, ginseng, bitter orange, valerian, or hawthorn

Finding the source

Palpitations come and go. They are usually gone in the doctor's office. That makes pinning them down a joint effort. One of the most helpful pieces of information is your story of how your palpitations feel, how often they strike, and when. When you have palpitations, try to gauge your heart's rhythm (is it fast or slow? regular or irregular?). Do you feel lightheaded, dizzy, or out of breath, or do you have chest pain? Are you often doing the same thing when they occur? Do they start and stop suddenly, or fade in and out?

A physical exam can reveal telltale signs. When listening to your heart, your doctor may hear a murmur or other sound suggesting a problem with one of the heart's valves, which can cause palpitations. He or she may also discover a thyroid imbalance, signs of anemia, low potassium, or other problems that can cause or contribute to palpitations.

An electrocardiogram (ECG) is a standard tool for evaluating someone with palpitations. This recording of your heart's electrical activity shows its rhythm and any overt or subtle disturbances, but only over the course of 12 seconds or so. Your doctor may want to record your heart rhythm for longer to identify the cause of the palpitations.

If your palpitations come with chest pain, your doctor may want you to have an exercise stress test. If they come with a racing pulse or dizziness, an electrophysiology study using a special probe inserted into the heart may be in order.

Capturing the problem

Sometimes it's important to identify the source of palpitations. If you are at risk for a heart-rhythm problem or if palpitations are interfering with your life or mental health, recordings of your heart's rhythm that last longer than an ECG offer a way to capture an electrical signature of the problem.

A Holter monitor constantly records your heart's rhythm for 24 to 48 hours as you go about your daily activities. Small patches called electrodes are stuck onto your chest and attached to a recorder that's carried in a pocket or a pouch worn around the neck or waist. During the test, you should keep a diary of what you do and how you feel together with the time. When you return the monitor to your doctor, he or she will look at the recording and see if there have been any irregular heart rhythms.

Sometimes even 48 hours isn't long enough to spot the culprit. An event recorder can monitor the heart for weeks. There's even an implantable recorder that can invisibly monitor the heart for a year or more.

What to do

If you have unexplained palpitations, start with the simple things first: Try cutting back on caffeine, or giving it up altogether, to see if it is contributing to the problem. Smoking can cause palpitations, as can alcohol. Beware of over-the-counter decongestant medications that contain pseudoephedrine or phenylephrine. Make sure you eat regularly (low blood sugar can cause palpitations) and drink plenty of fluids. Get enough sleep.

Stress and anxiety are two other key triggers of palpitations. A two-step approach can help here. Meditation, the relaxation response, exercise, yoga, tai chi, or other stress-busting activities may help keep palpitations away. If they do appear, breathing exercises or tensing and relaxing every muscle group in your body can ease the panic or anxiety spurred by palpitations that sometimes feeds into creating more of them.