Premature Ventricular Contractions (PVCs)

Premature ventricular contractions are called PVC’s, and they are abnormal heartbeats that originate in one of the two ventricles (the lower chambers responsible for pumping blood). PVC’s are extra beats that interfere with normal sinus rhythm (NSR-normal heart rhythm). NSR normally starts in the right atrium (upper right chamber), so when a PVC occurs in the ventricle it feels like a missed beat sometimes followed by a “flip-flop” sensation in the chest. PVC’s are common and most people have them if they live long enough.

If you are having PVC’s you may be feeling a fluttering in the chest, or a flip-flop sensation. You may also experience skipped heartbeats, or feel a pounding in the chest-over all you feel an awareness of your chest at all times, because you feel something so frequently. There are other names for PVC’s which are: premature ventricular complexes; ventricular premature beats; extrasystoles (pronounced extra-sis-tow-lees)-meaning extra heartbeats; and ectopic beats-meaning beats outside normal heart chamber.

For most people PVC’s are not a problem, but if you have them frequently they may be a symptom of underlying heart problems. There may be many reasons people experience PVC’s. Normally your heart is electrically programmed to work in a specific way; the rhythm is controlled by the SA (sinoatrial) node-which is the natural pacemaker of the heart that triggers the heartbeat. The heart beats because the electrical impulses travel from the SA node in the atrium to the ventricles. The electrical impulse then causes the ventricles to contract, which then pumps the blood out of the heart and into the lungs and out to the body. The normal heartbeat is approximately 72 beats per minute, so the SA node fires an impulse for each contraction of the heart. PVC’s interfere with this normal sequence of events to disrupt the normal heartbeat.

The exact cause of PVC’s is not know, but there are many factors associated with them, which include: certain medications-especially asthma meds; drinking alcohol; drug abuse; high blood pressure; anxiety; use of caffeine; injury to heart muscle-related to heart disease; chemical imbalances in the body; fluid and electrolyte imbalances; and smoking. As a general rule, if you are having as many as 5 PVC’s a minute over long periods of time; you should see your doctor to be evaluated. There may be absolutely nothing wrong, but then again there may be an underlying heart problem, so it is better to err on the side of safety and get checked, even if it turns out to be nothing.

Your doctor will ask you how long you have been feeling the sensations, and he/she may ask you to describe what you are feeling. If PVC’s are suspected, your doctor will order tests that include an electrocardiogram (EKG or ECG), to visualize the electrical conductivity of your heart at that moment in your office. He/she may ask you to wear a Holter monitor ECG recorder to record your cardiac activity for a 24 hour period. The Holter monitor can pick up anomalies in your heartbeats during all of your waking and sleeping hours. When you feel an ectopic beat, fluttering or any other symptom of discomfort you can press a button to indicate that you felt something. Your response will be noted in the recording. You may also be asked to perform a stress test, which is a special EKG machine that records your heart’s activity during exercise. You will be walking on a treadmill or exercise bike when the test is going on. This EKG will record your heart’s electrical function.

The benefit of the cardiac testing such as the Holter monitor is that these tests can identify the type of PVC you are having. There are two types of PVC, and they are the bigenimy and the trigenimy. The bigenimy is a ventricular pattern of alternating normal beats with premature ectopic beats-this one is usually associated with heart problems-can be life threatening. The trigenimy is two normal beats followed one ectopic beat-this one is usually harmless.

In most cases, PVC’s are harmless and do not require treatment, but for those who have underlying heart problems, the PVC’s could lead to cardiac rhythm problems. Some people are so bothered by the dysrhythmia they have to make lifestyle changes and take medications to suppress the contractions. If you are having PVC’s and they are bothersome to you, track them. Jot down the time and what you are doing when you have them. Tracking your PVC’s will help you identify what actually triggers them. You may be able to avoid them by avoiding the triggers.

Some of the common triggers are smoking, drinking caffeine, and anxiety. You may be able to decrease your premature contractions by avoiding tobacco and caffeine. If anxiety is a problem, you might talk to your doctor about ways to reduce stress. Exercise and biofeedback machines are helpful in reducing stress. Certain anti-anxiety medications are also beneficial in reducing your response to stress. It is important to be compliant with your plan of care. If your doctor asks you to stop smoking, or to stop drinking caffeine-do it. Your health-when it is all said and done-is your responsibility.

Source: Mayo Clinic information page