Why is your heart rhythm different?
An arrhythmia isn’t something that you usually have to worry about. Some can occur without you even knowing you have one. Others are life-threatening and need immediate medical treatment. What exactly is an arrhythmia? How do you know whether the type you have is serious? What can be done to correct it?
An arrhythmia is when the electrical impulses that regulate your heart rate aren’t functioning the way they should and causes the heart to beat too fast, slow, or irregularly. To understand arrhythmias, it’s key to know the basic structure and function of the heart. The heart has four chambers with two atria on top and two ventricles on the bottom. To pump blood throughout the body, they need to receive a signal to contract at the right time from the control of the electrical pathway. The pathway starts in the sinus node, which is located in your right atrium. Once the sinus node initiates the electrical process, it moves across the atria and signals the muscles to contract, sending the blood in them into the ventricles. The electrical signal reaches the atrioventricular (AV) node, which slows the impulse down slightly before sending it to the ventricles, allowing them to receive the blood from the atria before getting the signal to contract and send that blood throughout your body. The average resting heart rate is between 60 – 100 beats per minute.
Most arrhythmias are classified by rate and where it originates from, either the top or bottom parts of your heart. If the rate is above 100, it’s called tachycardia; if it’s below 60, it’s called bradycardia.
Tachycardic rhythms that start in the atria are atrial fibrillation, atrial flutter, and supraventricular tachycardia. Atrial fibrillation (AFib) is when your sinus node has chaotic electrical impulses signaling the atria to contract rapidly. These contractions are uncoordinated and weak, meaning that the blood in your atria isn’t usually pumped into the ventricle as it should. Instead, the blood pools in the atria and increases the risk of developing a blood clot. These abnormal electrical impulses also affect the AV node, which tells the ventricles to contract rapidly at an irregular rate (not usually as fast as the atria). Atrial flutter (AFlutter) is like atrial fibrillation in the cause, but the rhythm is less uncoordinated. Supraventricular tachycardia (SVT) describes any other type of arrhythmia that starts above the AV node and ventricles. One example of this is Wolff-Parkinson-White (WPW) Syndrome.
Tachycardic rhythms that start in the ventricles are usually more serious because they’re more life-threatening. Ventricular tachycardia (VTach) is similar to atrial fibrillation in that there are chaotic electrical impulses that signal the ventricles to contract rapidly, but the origin of the impulses comes from the AV node rather than the sinus node. Like AFib, these contractions are uncoordinated and weak, so the ventricles can’t pump sufficient blood to the rest of the body. If not treated quickly, it can turn into ventricular fibrillation. Ventricular fibrillation (VFib) is when the abnormal electrical impulses occur so rapidly that your ventricles don’t have time to contract, so they quiver, not allowing blood to be pumped out of them. If this isn’t corrected within a few minutes, it’s usually fatal. Long QT syndrome is a disorder that increases the risk of developing fast, frenzied heartbeats that result in fainting or, in some cases, sudden death. It’s often the result of a genetic mutation, congenital heart defect, or certain medications.
A premature heartbeat is when you have an extra beat (it might feel like your heart skipped a beat) and is often the result of stress, strenuous exercise, or stimulants. It isn’t uncommon for these to happen occasionally and doesn’t usually indicate that you have a serious problem. The concern is that if you have a history of heart disease or another underlying risk, a premature heartbeat can cause an arrhythmia.
It’s important to note that having a bradycardic heart rhythm doesn’t necessarily signify a problem. For very athletic people, it isn’t uncommon to have a normal resting heart rate below 60 beats a minute. Also, one of the side effects of certain medications is having a lower heart rate. The concern arises when the heart rate is slow to the point the body can’t pump enough blood throughout the circulatory system. Sick sinus syndrome is when the sinus node isn’t sending the electrical impulses correctly, resulting in the heart rate being too slow or causing an intermittent speeding up and slowing down of the rate. Sometimes, it results from scar tissue near the sinus node blocking the travel of the electrical impulses. A conduction block is similar in that electrical impulses are blocked or delayed, but the location is usually closer to the AV node or down the individual ventricle electrical pathways.
Any changes in the heart rhythm can cause a fluttering feeling in the chest (palpitations), chest pain, sweating, shortness of breath, lightheadedness, dizziness, or fainting. Sometimes, it might feel like your heart is racing or going too slow.
Due to the wide variety of arrhythmia types, numerous possible causes exist. Some reasons directly related to the heart are if the person is currently having a heart attack, scar tissue from a prior heart attack, anything that interrupts the normal flow of electrical impulses, changes to your heart’s structure, coronary artery disease, congenital heart problems, or a family history of arrhythmias or other heart problems.
Other non-heart reasons for arrhythmias include diabetes, sleep apnea, electrolyte imbalance, high blood pressure, thyroid problems (either over or under active), smoking, drinking too much alcohol/caffeine, abuse of drugs, taking certain medications, and being under a lot of stress.
The treatment for arrhythmias depends on the type. For tachycardic rhythms, there are several options. The initial thing that your doctor might try is called a vagal maneuver. They will instruct you to cough, bear down like you’re having a bowel movement, or put an ice pack on your face. These techniques stimulate your vagus nerve, which helps regulate your heartbeat. It isn’t effective for all types of tachycardia, so the doctor might need to give you an injection of an anti-arrhythmic medication to change your heart rhythm.
If the injection works, you’ll be prescribed medication to take at home to help keep your heart rhythm under control. If the injection doesn’t work, your doctor might try a cardioversion procedure, where they send an electrical signal to your heart by placing patches on your chest and sending a shock through them. The process should return your heart to a normal rhythm.
A permanent solution is an ablation, which is when a catheter is inserted into one of your blood vessels and guided to your heart. Once in position, the tip of the catheter is heated, destroying the tissue to create a block along the electrical pathway that’s causing the problem.
Another possible surgical option is a maze procedure. It involves a surgeon making a series of surgical incisions in the heart tissue in the atria to create a pattern or maze of scar tissue. While very effective, it’s usually reserved for people who don’t respond to other treatments since it involves open heart surgery.
The doctor may recommend implanting a device that can help control abnormal heart rhythms, such as a pacemaker or implantable cardioverter-defibrillator (ICD). Both devices are small and usually placed under your skin near your collarbone. From the device, an insulated wire extends to your heart and is permanently anchored to it.
A pacemaker is used for either tachycardic or bradycardic rhythms. It’s usually the only treatment for bradycardic rhythms with no underlying cause that can be corrected. If the pacemaker detects either rhythm, it will send an electrical impulse to your heart, signaling it to beat normally.
An ICD is primarily used for individuals with VTach, VFib, or sudden cardiac arrest because it can send out low or high-energy shocks to reset your heart to a normal rhythm (much like external cardioversion).
Besides these interventions, your doctor will recommend that you make lifestyle changes to improve your heart health. These changes are the same as prevention techniques, so we’ll take a closer look at them in the next section.
The best way to prevent an arrhythmia is by living a heart-healthy lifestyle. A key step is to eat a diet low in salt and solid fats but rich in fruits, vegetables, and whole grains. It’s also essential to increase your level of physical activity with the goal of doing some form of exercise daily. By doing both of these things, you’ll be able to maintain a healthy weight, which is vital since being overweight increases your chances of having heart disease. Eating healthy and exercising will also help you control your blood pressure and cholesterol levels. Both of these impact your heart significantly and can contribute to arrhythmias.
If you smoke, quit. If you don’t smoke, avoid being around people who do because secondhand smoke harms your health. Be careful when using over-the-counter medications. Some cold and cough medicines contain stimulants, which can trigger a rapid heart rate. If you drink alcohol or caffeine, do so in moderation. It’s critical to reduce the amount of stress in your life. Participating in activities like yoga, meditation, and relaxation techniques, can be extremely beneficial. Some individuals feel that acupuncture and omega-3 fatty acids might help reduce stress and prevent arrhythmias, but further research is needed.
Having any arrhythmia can come as a shock, especially if it’s life-threatening. The good news is that there are ways to manage them so you can live a healthy life. If you have any questions or concerns about arrhythmias, please speak with your doctor. If you would like more information, please visit the National Heart, Lung, and Blood Institute’s arrhythmia page at https://www.nhlbi.nih.gov/health-topics/arrhythmia