Premature Ventricular Contractions
What are premature ventricular contractions (PVCs)?
Premature ventricular contractions, or PVCs, are a type of abnormal heartbeat. Your heart has 4 chambers: 2 upper atria and 2 lower ventricles. Normally, a special group of cells start the signal for your heartbeat. These cells are in the sinoatrial (SA) node in the right atrium. The signal quickly moves down your heart's conducting system. It travels to the left and right ventricle. As it travels, the signal triggers nearby parts of your heart to contract. This allows your heart to squeeze in a coordinated way.
With a PVC, the signal to start your heartbeat comes from one of the ventricles instead. This signal is premature, meaning it happens before the SA node has had a chance to fire. The signal spreads through the rest of your heart and can cause a heartbeat that is different than normal. Depending on when the premature beat happens, you may feel nothing at all, a skipped heartbeat, lightheaded, short of breath, or even chest pain.
PVCs that happen only once in a while are common in people of all ages, but they are a more common in older people. PVCs can happen in people without any heart disease, but they are more common in people with some kind of heart disease. PVCs rarely cause problems unless they occur again and again over a long period of time. In such cases they can lead to a PVC-induced cardiomyopathy, or a weakening of the heart muscle from too many PVCs. Most often, this can go away once the PVCs are treated.
What causes PVCs?
Certain things can help set off a premature signal in the ventricles, such as:
- Reduced blood flow to your heart for any reason
- Acute heart attack (myocardial infarction)
- Cardiomyopathy or heart failure
- Electrolyte problems such as low magnesium or potassium levels
- Increased adrenaline such as from stress or anxiety
- Certain medicines, such as digoxin
Who is at risk for PVCs?
Many heart conditions increase the risk for PVCs. These include:
- Mitral valve prolapse
- High blood pressure
- Heart attack
- Coronary heart disease
- Dilated cardiomyopathy
- Hypertrophic cardiomyopathy
- Congenital heart disease
- Heart failure
What are the symptoms of PVCs?
Most people with occasional PVCs do not have symptoms. When symptoms do happen, they are usually minor. Sometimes PVCs cause an unpleasant awareness of the heartbeat (palpitations). Some people may describe feeling a “skipped” or “extra” heartbeat. Dizziness, near-fainting, and a pounding sensation in the neck are other possible symptoms.
Generally, PVCs cause dangerous symptoms only if the person has another heart problem. For example, they might happen in someone whose ventricle already squeezes poorly. So if you have heart failure, you may notice more symptoms, like shortness of breath. You may also be more likely to have symptoms the more PVCs you have.
How are PVCs diagnosed?
Your healthcare provider will ask about your health history and give you a physical exam. An irregular heartbeat may heard when the healthcare provider listens to your heart with a stethoscope. An electrocardiogram (ECG) may be done. This is usually the first test for diagnosis. This test lets your healthcare provider see the signal of your heartbeat as it moves through the heart during a short amount of time. If you have any PVCs while the ECG is being done, they will show up on the ECG. In some cases, your healthcare provider might recommend ECG monitoring over a day or two, or up to 30 days. This can be done with Holter monitors or other types of heart monitors. This can help to catch PVCs that don’t happen often.
These may be the only tests your healthcare provider will need. You may need more testing if you have PVCs often, or many in a row. Your healthcare provider may do some testing to look for other causes, including potential heart problems. These tests might include:
- Echocardiography, to evaluate heart structure and function
- Cardiac stress testing, to see how your heart responds to exercise and to evaluate blood flow through your heart
- Blood tests, to check potassium and thyroid hormone levels
How are PVCs treated?
Most often, PVCs that happen only once in a while don't need any treatment. If you have another problem with your heart that is treated, your PVCs may decrease. For example, you might take a medicine to lower your blood pressure or lower your heart rate. This may lower how often you have PVCs.
In some cases, specific treatment may be done to help prevent PVCs. These are used only if you have symptoms from PVCs or if there is concern that the PVCs are frequent enough to be damaging your heart. Choices include:
- Beta-blockers or calcium channel blockers
- Medicines called antiarrhythmics,These help prevent abnormal heart rhythms.
- Catheter ablation, to destroy the part of your heart responsible for the abnormal beats
How do I manage PVCs?
Your healthcare provider may give your more instructions about how to manage your PVCs and other medical conditions. These may include:
- Eating a heart-healthy diet
- Getting enough exercise and maintaining a healthy weight
- Not having too much alcohol and caffeine, which can trigger PVCs
- Not having too much stress and fatigue, which can also trigger PVCs
- Getting treatment for your other health conditions such as high blood pressure
- Making sure to keep all your medical appointments
When should I call my healthcare provider?
See your healthcare provider right away if you have severe symptoms like chest pain, lightheadedness, or sudden shortness of breath. If your symptoms are getting worse over time, plan to see your healthcare provider soon.
Key points about PVCs
- PVCs are a kind of abnormal heart rhythm. The signal to start your heartbeat starts somewhere in the ventricles instead of in the SA node. This can feel like a skipped heartbeat or an extra heartbeat.
- PVCs are very common in people of all ages. They are more common if you have other heart problems.
- PVCs can cause symptoms, but often they do not. When they happen only once in a while, PVCs don't need treatment.
- Medicines and catheter ablation are options if you have PVCs that cause symptoms or occur often .
- Your healthcare provider may want to check you for other heart conditions.
- Follow all your healthcare provider’s instructions about medicine, exercise, and lifestyle.
Tips to help you get the most from a visit to your healthcare provider:
- Know the reason for your visit and what you want to happen.
- Before your visit, write down questions you want answered.
- Bring someone with you to help you ask questions and remember what your provider tells you.
- At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
- Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
- Ask if your condition can be treated in other ways.
- Know why a test or procedure is recommended and what the results could mean.
- Know what to expect if you do not take the medicine or have the test or procedure.
- If you have a follow-up appointment, write down the date, time, and purpose for that visit.
- Know how you can contact your provider if you have questions or an emergency.