Types and Causes of an Irregular Heartbeat

What does an irregular heartbeat mean?

An irregular heartbeat is also medically termed as arrhythmia or dysrhythmia. An irregular heartbeat happens when the heart’s electrical signals that coordinate with your heartbeat are not properly functioning. 

When you have an arrhythmia, your heart may:

• Beat faster (tachycardia)
• Beat too slowly (bradycardia)
• Beat very early (premature contraction) 
• Beat irregularly (flutter or fibrillation)

A healthy individual at rest usually has a heart rate of 60-100 beats/minute. Physically fit people tend to have a lower resting heart rate. At rest, athletes usually have a heart rate of fewer than 60 beats/minute because their hearts are efficiently functioning. 

Types

There are various types of arrhythmia and they include:

• Premature Ventricular Contractions or PVCs: They are the most common type of arrhythmia, which is mostly observed in individuals with or without heart disease. It is also described as a skipped heartbeat, which we might have occasionally experienced at some point in our lives. In certain people, it can be due to stress, too much intake of nicotine or caffeine, or by carrying out high-intensity workouts. However, in certain cases, PVCs are also known to occur due to heart diseases or when there is an imbalance of electrolytes. Although PVCs are usually harmless and do not cause symptoms, individuals who often have PVCs or experience symptoms associated with it should consult a cardiologist (a doctor who specializes in heart disorders) for evaluation. 

• Premature Atrial Contractions (PACs): These beats originate from the atria or the heart's upper chambers. These are also called as early additional beats. These contractions are most of the time harmless and would not need any treatment.

• Atrial Flutter (AFL): In this type of arrhythmia, the heart abnormally beats faster in a regular pattern. It is caused by either one or more rapid circuits in the atrium. An atrial flutter is known to occur most often among individuals who suffer from heart diseases and those who are in their first week after a heart surgery. An atrial flutter can eventually convert itself to atrial fibrillation (AFib).

• Atrial Fibrillation (AFib): It is one of the most common types of irregular heartbeat. It causes abnormal contraction of the atria and the upper chambers of the heart.

• Accessory Pathway Tachycardias (APT): An extra abnormal pathway or connection in between the ventricles and the atria causes it. The impulses travel through these extra abnormal pathways and through the usual route. In this case, the heart unusually beats very fast because the impulses around the heart travel very quickly.

• Paroxysmal Supraventricular Tachycardia or PSVT: A type of arrhythmia that abruptly starts and ends. It causes a rapid heart rate along with a regular rhythm. It originates from the ventricles. 

• AV Nodal Reentrant Tachycardia: A rapid heart rate may occur due to multiple or more than one pathways via the AV node. This can result in fainting, heart palpitations, or heart failure. In most of the cases, it can be terminated or stopped by carrying out simple exercises, which include breathing in and then bearing down. Other exercises can be performed with the help of trained medical professionals. There are certain medications that can also help in stopping this type of abnormal heart rhythm.

• Ventricular Fibrillation: The impulses from the ventricles can be erratic and disorganized. In this case, not enough blood is pumped by the ventricles due to erratic impulses. It is a medical emergency that should be treated with cardiopulmonary resuscitation (CPR) and defibrillation without delay.

• Ventricular Tachycardia: It is a type of fast heart rate, which comes from the lower chambers or ventricles of the heart. The heart is not filled with an adequate amount of blood due to a rapid or fast heart rate. For this reason, less blood is pumped throughout the body. This particular type of irregular heartbeat can turn out to be really serious, especially for individuals who suffer from heart problems. There are also chances that it can be associated with other symptoms. 

• Sinus Node Dysfunction: It causes a slow rhythm of the heart due to a dysfunction of the sinus node. Major cases of sinus node dysfunctions have to be treated with the help of a pacemaker.

• Heart Block: In this case, there is a block or delay of the heart's electrical impulses as they go through the sinus node and the heart's lower chambers. A pacemaker may be needed in serious cases. 

Causes

If the electrical impulses are interrupted, it causes the heart to contract, which ultimately leads to irregular heartbeats. For an individual who has a healthy heart, the ideal heart rate while at rest should be in between 50-100 beats/minute. If people are more physically fit, their resting heart rate is slower. There are a number of reasons for the heart to work incorrectly and causing irregular heartbeats and they include:

• Mental, emotional, or physical stress
• Diabetes
• Excessive consumption of caffeine 
• Use of certain medications
• Alcohol or drug abuse
• High blood pressure or hypertension
• An overactive thyroid gland (hyperthyroidism)
• Herbal treatments
• Certain dietary supplements
• Scarring of the heart 
• Smoking
• Congestive heart failure or any kind of heart disease
• Any changes in heart structure

Unless there are external triggers such as drug abuse or an electrical shock, a healthy person would hardly suffer from long-term arrhythmia. If there are other underlying medical problems, the electrical impulses would not be able to properly travel through the heart, which increases the risk of having an irregular heart rhythm.

Our heart is composed of four different chambers, which is divided into two atria (upper chambers) and two ventricles (lower chambers). It is powered with the help of an electrical system that puts our pulses in a regular rhythm. These pulses are known to keep our heart always pumping, thereby allowing a free flow of blood to the lungs and other parts of the body. When the heart beats way too fast or too slow, then an individual may have an arrhythmia.

A slight change in the heart’s rhythm feels like a strong heartbeat, which is commonly referred to as a palpitation. Sometimes, it is described as "fluttering in the chest".

There is nothing to worry about if your heartbeat becomes occasionally irregular and you do not have other symptoms such as lightheadedness, shortness of breath, or dizziness. It is a quite common occurrence for small children to have an extra heartbeat. In the case of healthy children, an extra heartbeat is also not a cause for concern. 

Changes in Heart Rate

Most heart rate changes are only minor cases, which may not need any medical intervention if there are no accompanying symptoms or history of any heart disease. Drinking alcohol, excessive caffeine intake, smoking, taking diet pills, and cough medicines can cause the heart to work faster or tend to skip a beat. The heartbeat changes when an individual is under a lot of stress or pain. If an individual is not feeling well or suffering from any illness, then the heartbeat can become faster. Moreover, when a person carries out intensive exercises, then it can mostly lead to an increase in one's heart rate, which can lead to changes in the rhythm of the heart.

Dietary supplements such as goldenseal, motherwort, ephedra (ma-huang), and oleander can lead to irregular heartbeats in an individual. It is also quite common for pregnant women to have minor changes in their heartbeat.  However, if an individual starts to experience other symptoms such as fainting and lightheadedness, a medical assessment must be done.

When to worry about an irregular heartbeat?

An irregularity in the heartbeat changes the amount of blood that passes or flows to the lungs and other parts of the body. The amount of blood, which the heart pumps can be reduced when the heart beats too fast or too slow.

Certain changes in the heartbeat such as atrial fibrillation tend to start in the upper chambers of the heart. This condition can be serious. The reason is that the risk of developing a blood clot also increases in this condition. The condition ultimately leads to an increased risk of having a stroke or a blood clot in the lungs, which is also known as pulmonary embolism. People who have certain heart diseases, especially those who have a past history of a heart attack should always be more concerned with any changes in their usual heart rhythm.

Ventricular arrhythmia is an abnormally fast heartbeat. This type of irregular heartbeat can make it harder for the heart to pump enough blood to the brain and to the rest of the body, which can turn out to be life-threatening. Taking illegal drugs such as cocaine and abusing any kind of prescription or over-the-counter medicine can lead to serious heart issues, which ultimately pose a huge health threat. Hence, the FDA has banned the sale of ephedra, which has been associated with stroke, heart attacks, and sudden death in individuals.

Living with Arrhythmia

• Take your medications as prescribed by the doctor. Do not stop taking your medications without your doctor's advice. Inform your doctor immediately if you experience any side effects. 
• Certain substances that can contribute to an irregular heartbeat should be avoided such as tobacco, alcohol, caffeine, cold and cough medications, psychotropic drugs, appetite suppressants, antiarrhythmic drugs, and beta blockers.
• You should know how to take your pulse and keep a record of it. Keep a record of the day, time, and note how you felt while taking your pulse.
• Certain factors that can increase the risk of arrhythmia should be controlled such as high blood pressure, being overweight, high cholesterol levels, and smoking.