Palpitations: Heart Rhythms Gone Haywire

By Sarah Samaan, Rosanne Rust, Cynthia Kleckner

Because your heart is not only a strong muscle but also an incredible network of electrical tissue, sometimes things can go a bit haywire. Heart rhythm problems run the spectrum from mildly irritating to life-threatening. Following are some common heart rhythm abnormalities:

  • Premature atrial contractions (PACs): These are irregular beats that originate in the atria, or top chambers, of the heart. About half of people with normal, healthy hearts have a few of these every day. When they occur singly or in brief groupings, they can sometimes be uncomfortable but rarely harmful. Stress, fatigue, excessive caffeine, low potassium or magnesium, and thyroid problems are common causes.

  • Premature ventricular contractions (PVCs): PVCs originate in the ventricles, or bottom pumping chambers of the heart. Like PACs, it’s normal to have a few PVCs over the course of a day. Some people feel them, but most people don’t. The same triggers for PACs can also generate PVCs. However, PVCs are more common in people with weak or damaged hearts and in people with abnormal heart valves.

  • Atrial fibrillation (a-fib): A-fib is a potentially dangerous heart rhythm that usually requires medical therapy. It’s caused by a continually erratic rhythm that starts in the atria. Usually, but not always, it causes a rapid, irregular heart rate that feels very uncomfortable. Doctors take a-fib very seriously, not only because it makes your heart work so hard but also because it’s a leading cause of stroke.

    When the heart is in a-fib, blood clots can form in the atria. If those clots break free, they can travel to the brain and cut off blood flow, causing permanent damage to the brain tissue. Thankfully, good medicines are available to prevent this from happening.

  • Ventricular tachycardia (v-tach): V-tach happens when a rogue bundle of electrical tissue in one of the ventricles takes over the heart rhythm. It often happens for just a few beats, but in more serious instances, it can go on for minutes and, rarely, even longer. It can temporarily drop blood pressure and reduce blood flow to the brain and other organs.

    Although v-tach can occur in healthy hearts, it’s more common in people with weak or scarred hearts. If you’ve had a large heart attack in the past, you’re especially at risk. V-tach is a potentially very dangerous rhythm because it can degenerate into ventricular fibrillation, a rhythm that’s nearly always fatal without prompt treatment.

The sensation of an irregular heartbeat is referred to as palpitations. The specific type of irregular heartbeat can be tricky to self-diagnose. If you suspect any change in your sense of heart rhythm, play it safe and visit your doctor.

If you’re experiencing frequent palpitations combined with dizziness or chest discomfort, contact your doctor or (in the case of severe or persistent symptoms) seek emergency care. The cause of your symptoms can usually be readily sorted out with an EKG (an electrical tracing of the heart rhythm) or a heart monitor.

Your doctor will probably order blood work and may also order an echocardiogram, or sonogram, of the heart. Treatment, if needed, typically involves medication, although in some more serious cases, a surgical procedure may be required.