Premature ventricular contractions (PVCs)

Overview

Premature ventricular contractions (PVCs) are extra heartbeats that begin in one of your heart's two lower pumping chambers (ventricles). These extra beats disrupt your regular heart rhythm, sometimes causing you to feel a fluttering or a skipped beat in your chest.

Premature ventricular contractions are common — they occur in many people. They're also called:

• Premature ventricular complexes
• Ventricular premature beats
• Ventricular extrasystoles

If you have occasional premature ventricular contractions, but you're otherwise healthy, there's probably no reason for concern, and no need for treatment. If you have frequent premature ventricular contractions or underlying heart disease, you might need treatment.

Symptoms

Premature ventricular contractions often cause few or no symptoms. But you might feel an odd sensation in your chest, such as:

• Fluttering
• Pounding or jumping
• Skipped beats or missed beats
• Increased awareness of your heartbeat

When to see a doctor

If you feel fluttering, a sensation of skipped heartbeats or odd feelings in your chest, talk to your doctor. You'll want to identify the source of these symptoms, whether it's PVCs, other heart rhythm problems, serious heart problems, anxiety, anemia or infections.

Causes

Your heart is made up of four chambers — two upper chambers (atria) and two lower chambers (ventricles). The rhythm of your heart is normally controlled by the sinoatrial (SA) node — or sinus node — an area of specialized cells in the right atrium.

This natural pacemaker produces the electrical impulses that trigger the normal heartbeat. From the sinus node, electrical impulses travel across the atria to the ventricles, causing them to contract and pump blood to your lungs and body.

PVCs are abnormal contractions that begin in the ventricles. These extra contractions usually beat sooner than the next expected regular heartbeat. And they often interrupt the normal order of pumping, which is the atria first, then the ventricles.

Why do extra beats occur?

The reasons aren't always clear. Certain triggers, heart diseases or changes in the body can make cells in the ventricles electrically unstable. Heart disease or scarring may also cause electrical impulses to be misrouted.

Premature ventricular contractions can be associated with:

• Certain medications, including decongestants and antihistamines
• Alcohol or illegal drugs
• Increased levels of adrenaline in the body that may be caused by caffeine, tobacco, exercise or anxiety
• Injury to the heart muscle from coronary artery disease, congenital heart disease, high blood pressure or heart failure

Risk factors

The following can increase your risk of PVCs:

• Caffeine , tobacco, alcohol and illicit drugs
• Exercise — if you have certain types of PVCs
• High blood pressure (hypertension)
• Anxiety
• Heart disease, including congenital heart disease, coronary artery disease, heart attack, heart failure and a weakened heart muscle (cardiomyopathy)

Complications

Having frequent PVCs or certain patterns of them might increase your risk of developing heart rhythm problems (arrhythmias) or weakening of the heart muscle (cardiomyopathy).

Rarely, when accompanied by heart disease, frequent premature contractions can lead to chaotic, dangerous heart rhythms and possibly sudden cardiac death.