Medical Edge Newspaper Column

Fluttery Heartbeat After Exercise Should Be Checked Out

May 22, 2006
DEAR MAYO CLINIC:
I'm a 62-year-old woman with mild mitral valve prolapse. After one of my recent, normal workouts, I felt very strange: weak, clammy palms and a fluttery heartbeat. The symptoms lasted about 15 minutes. What could be going on? Should I be worried? -- E. Northport, N.Y.

ANSWER:
Your description of a fluttery heartbeat after exercise could be a normal heart-rate response to exercise. The heart's electrical system regulates the heartbeat so that the heart normally contracts 60 to 100 times per minute at rest. Contractions will increase with exercise as the body requires more blood flow.

That fluttery feeling also could be from an abnormal heart rhythm or arrhythmia.

Abnormal heart rhythms can originate from the bottom chambers of the heart (ventricles) or the top chambers of the heart (atria). Since the ventricles are the main pumping chambers of the heart, abnormal heart rhythms originating from the ventricles usually cause severe symptoms, such as passing out.

If your symptoms are due to an abnormal heart rhythm, it is more likely that your arrhythmia is originating from the top portion of the heart. Arrhythmias from the atria can cause feelings of light-headedness or weakness because the heart is not beating as efficiently as possible.

The most common arrhythmia originating from the atria are single extra beats. In this circumstance, the isolated extra heartbeats can cause fleeting symptoms that are commonly called palpitations. Single extra beats are normal and are generally not a cause for concern.

In some cases, people develop longer-lasting arrhythmias. The most common and clinically important longer-lasting arrhythmia arising from the atria is atrial fibrillation. With this condition, the atria beat chaotically and rapidly instead of contracting regularly at a normal rate. The rapid atrial activity leads to rapid heart rates.

Atrial fibrillation is more common as people age and is associated with high blood pressure, diabetes and heart failure. Atrial fibrillation can be observed in patients with mitral valve prolapse, where the mitral valve bows a little when the left ventricle contracts. Atrial fibrillation is not life-threatening but can increase a person's risk of stroke. The general public has become more aware of atrial fibrillation since several high-profile sports figures, including Bill Bradley and Mario Lemieux, had episodes of it.

It is important for you to see your physician. After performing a general history and physical examination, your physician may order an echocardiogram to determine whether your mitral valve prolapse has changed.

The most critical information to assess your condition will be a recording of your heart's electrical activity, which can be accomplished in a number of ways. The information will help determine whether you have a serious arrhythmia and will help your physician formulate a treatment plan, if necessary. Fortunately, most arrhythmias, whether ventricular or atrial, can be treated with medications or cardiac procedures.

-- Fred Kusumoto, M.D., Cardiology, Mayo Clinic, Jacksonville, Fla.