Everyone is interested in keeping their health in the best shape, but with so many risks around us, we hardly know what really is good for our health. Whether it’s having extra fries with a cheeseburger, enjoying a can of soda or asking for an additional dip, these guilty pleasures hide more health threats than we imagine. These dietary indiscretions increase the chances of getting lifestyle-related conditions, such as obesity, increased cholesterol levels and diabetes, among others.
Add them up to a suite of conditions that are genetically inherited or to temporary dysfunctions that occur in otherwise normally functioning bodies, and it becomes increasingly harder to succeed. Premature ventricular contractions are an example of a common heart condition that occurs in many normal people, but that may indicate more serious heart problems.
What Are Premature Ventricular Contractions?
Premature Ventricular Contractions (PVCs) are abnormal early heartbeats that originate in the bottom chambers of the heart (ventricles). Just like Premature Atrial Contractions, they are responsible for the feeling that your heart “skips a beat.” Both conditions disrupt the normal rhythm, which is controlled by the electrical system of the heart. Most people don’t think about the electrical system, or “cardiac conduction system,” but essentially all cardiac rhythm disturbances (“arrhythmias”) arise from electrical problems in the heart.
A normal resting heart rate for adults is anywhere from 60 to 80 beats per minute (bpm), depending on age, level of fitness, and other factors. Therefore, the normal heart beats approximately once every second. The electrical signal that controls the heart beat arises from a specialized structure in the top of the right atrium. This electrical structure is known as the sinus node or sinoatrial node, and the signal it generates passes across the top chambers (atria) and down to the bottom chambers through another electrical structure called the AV (atrioventricular) node, which serves as the “main wire” connecting the top and bottom chambers. Every cell in the heart is capable of generating an electrical impulse. If a spot in the ventricle decides to “fire” prematurely, it overrides the sinus node and causes the heart beat to occur early, effectively shortening the time in between beats. This “premature ventricular contraction” also disturbs the normal timing of the heart chambers, since the bottom chambers now beat before the top chambers. This can give rise to symptoms like palpitations, fluttering or flipping of the heart, or give the sense that the heart “skipped” a beat. It can also cause a “rush” or fullness in the neck, a sensation of emptiness in the chest, and some people describe it like the feeling they get when an elevator suddenly starts dropping. PVCs sometimes give people the feeling that they have to cough. PVCs may occur on rare occasions or they can keep happening over and over for hours at a time.
In between normal heart contractions, the heart relaxes and fills up with blood coming from the veins. When a PVC occurs, there may not have been enough time for the heart to fill properly. The result is that the heart does not pump blood as efficiently when this rhythm disturbance is present, which can lead to a reduced blood pressure and symptoms of lightheadedness, weakness, and fatigue. People can also complain of a sense of shortness of breath when they are having PVCs frequently.
What Causes PVCs?
PVCs can occur in normal people. Most people over the age of 30 have some PVCs. In the absence of significant heart disease, PVCs are harmless. Many people don’t even realize they have them. PVCs can be associated with more serious problems if the heart is already diseased or if there are other medical problems underlying. Frequent PVCs can be triggered by:
- A chemical imbalance in the body
- Electrolyte deficiency
- A hormonal imbalance caused by too much adrenaline
- Certain medications
- Injury or damage of the heart muscle
- Lack of sleep
- Thyroid problems.
Some lifestyle habits can be considered risk factors that can lead to a frequent occurrence of premature ventricular contractions:
- Intense exercise
- Anxious situations or responses to stress
- Poor sleep habits
- Caffeine, nicotine, and alcohol consumption
- High blood pressure.
Making a Diagnosis
If you suspect there is something wrong with your heartbeat, check with your doctor. You can have an electrocardiogram (ECG or EKG), which is a recording of your heart’s electrical activity. If the PVCs are happening at the time, they will clearly show up on the ECG. Unfortunately, PVCs can sometimes occur sporadically during the day and they can be unpredictable. There might not be any occurring when the ECG machine is attached to your chest.
Depending on the frequency of the symptoms, the doctor might suggest that you to wear a Holter monitor. This device records your heart’s activity for 24 – 48 hours, and offers accurate details about the heartbeat pattern. It will count up every normal beat and record the abnormal ones as well. One advantage is that your doctor can see what percentage of your total heartbeats are made of PVCs and if they are coming from one spot in the ventricle or more than one.
Once the diagnosis of PVCs is made, your doctor will want to determine if they place you at risk of anything more serious. One way to establish if the PVCs are harmless or if there’s an underlying problem is the exercise stress ECG. During this test, you walk on a treadmill or pedal a bike, with ECG electrodes attached to your skin. They are connected to a monitor that indicates your heartbeats. Stress tests are mainly designed to detect coronary insufficiency, which is due to blockages in the arteries that feed the heart muscle. Rarely, PVCs can be a sign of coronary disease, but most of the time they are simply a minor electrical disturbance. If the premature beats cease when you start to exercise, it generally suggests that they are “benign.” However, if the PVCs get worse with exercise or if the heart starts racing continuously from the bottom chamber (an arrhythmia known as Ventricular Tachycardia), then a serious heart problem may be present. If that happens, further testing is necessary to figure out why and fix the problem, since ventricular tachycardia can be dangerous and even life-threatening.
What is the Best Treatment for PVCs?
Because PVCs are observed in healthy people and are generally not considered harmful, doctors try to reassure patients with mild symptoms and avoid any medications. Medications all have potential side effects, and so prescribing a pill may be doing more harm than good. Besides, not all medications are effective.
One remedy that has been proven to reduce PVCs is magnesium supplements. While extra magnesium should not be consumed by anyone with severe kidney problems, most people can take an extra 250-400 mg of magnesium oxide per day, which has been shown to reduce the symptoms from PVCs. Maintaining proper electrolyte (sodium, potassium) balance is essential to minimize electrical disturbances of the heart. Electrolytes are responsible for providing the micro-electric charges that generate the electrical activity of heart, muscle, and nerve fibers. Some advocate electrolyte-enhanced beverages, like sports drinks, though you should check with your doctor before consuming large amounts of these drinks. Be careful to not consume excessive calories or caffeine with those beverages, as those are the two most common additives in so-called “energy drinks.” Caffeine, in fact, can stimulate the heart and increase the number of PVCs that a person may have.
For people with severe symptoms, a cardiac specialist might recommend beta-blockers, which block the effects of adrenaline (epinephrine) on the heart. This reduces the heart rate and can decrease the symptoms of PVCs. A “calcium-channel blocker” known as verapamil may work better in some patients and is less likely to cause fatigue than beta blockers. In rare cases, stronger antiarrhythmic medications are recommended, but the overall benefit is still controversial. Careful monitoring is necessary when drugs are used to treat highly symptomatic PVCs. If the drug causes the heart to become too slow, then symptoms of fatigue, lightheadedness and exercise intolerance can occur. Not only that, but with slowing of the heart rate there will be additional time in between heartbeats, and this can actually encourage PVCs to occur, resulting in worsening of symptoms instead of making them better!
What you can do to alleviate the symptoms is to work on your lifestyle habits and reduce the potential triggers like alcohol, caffeine, and nicotine consumption. To have better control of your circulatory system’s health, you can engage in relaxing activities, which are known to promote a healthy blood flow throughout the body. Exercise helps reduce the symptoms of PVCs by regularly increasing your heart rate. This helps your heart learn to deal with every day stresses and makes the heart less sensitive to your body’s own adrenaline, so it can work like a “natural” beta blocker!
Should I Worry About PVC?
As mentioned before, PVCs are usually not harmful in normal people, so there’s nothing to worry about. You should alert your doctor if the premature contractions hinder you from accomplishing your routine tasks. You should also let your doctor know if you start feeling continuous rapid heartbeats, experience lightheadedness, chest pain, or if you lose consciousness (faint). Finally, make sure that frequent PVCs are not a symptom of a more serious heart condition that you might be unaware of.