ARRHYTHMIA

Welcome! In this article, we investigate the condition arrhythmia. Enjoy!

Cardiovascular diseases remain one of the leading causes of illness, with it resulting in 20.5 million deaths in 2025 alone. Arrhythmia is a condition that falls under the umbrella of cardiovascular diseases, where more than 50 million people worldwide are affected by the most common type of arrhythmia - atrial fibrillation. In this article, we delve into what arrhythmia really is, symptoms of this condition and ways to treat it.

What is Arrhythmia?

Arrhythmia is a condition in which the heart beats irregularly (this could mean your heart is beating too quickly, too slowly, or with an irregular rhythm).

Normally, your heart depends on an electrical system to beat accurately. This electrical system is called the cardiac conduction system, which controls the ‘rate and rhythm of the heartbeat’. The process of a heartbeat is essentially that an electrical signal travels from the top to the bottom of your heart, causing your heart to contract and pump blood. This all starts in a group of pacemaker cells placed in the sinoatrial (SA) node in the right atrium near the superior vena cava. For every heart cycle, two electrical signals are produced: one for pumping deoxygenated blood to the lungs and one for pumping oxygenated blood around the body. Arrhythmia affects this system and, therefore, results in an irregular heartbeat. There are many types of arrhythmia, and these are the most common:

Tachycardia - increased heart rate (more than 100 beats per minute at rest).
Bradycardia - slowed heart rate (less than 60 beats per minute at rest).
Atrial Fibrillation (AF) - the heart beats randomly due to improper release of electrical signals.
- Atrial comes from the two upper chambers in the heart (atria) where the pacemaker cells are located. Fibrillation comes from the electrical signals ‘twitching’ or ‘quivering’ rather than being steady and controlled.
Ventricular Fibrillation - the loss of electrical signals affects the ventricles, causing them to no longer contract properly.
- This is arguably one of the most dangerous types of arrhythmia as it results in a lack of oxygen being transported to the brain and vital organs, and so can potentially lead to cardiac death.

Symptoms of Arrhythmia

Shortness of Breath - not enough blood is pumped around the body, so less oxygen is being delivered to respiring cells. This results in anaerobic respiration and heavier breathing.
Episodes of Fainting - not enough blood is delivered to the brain, resulting in a lack of consciousness.
Fatigue - similar to shortness of breath.
Chest Discomfort - strain on the heart muscle due to irregular heartbeat, disrupting the regular pumping and flow of blood.
Heart Palpitations - disorganised electrical signals disrupt the natural rhythm of the heart.

Risk Factors

Many factors can increase a patient’s chance of developing arrhythmia, such as underlying heart conditions, pre - existing chronic health conditions, and even genetics and lifestyle factors can tend to play a role.

Underlying Heart Conditions: Conditions such as coronary artery disease can play a role in increasing the chance of developing arrhythmia, as they disrupt the heart’s specialised electrical system.
Excessive Alcohol Usage: Excessive alcohol usage can create toxic effects on the heart. An example of this is how alcohol can create inflammation of the myocardium (the muscular tissue of your heart), and this can lead to the buildup of fibrous scar tissue. The small amount of scar tissue physically blocks the electrical signals, forcing them to take an irregular pathway.
Obesity: The increased body volume and body weight force the heart to pump harder, stretching the heart chambers (atrial enlargement). The changes to the structure of the heart provide a place for increased erratic electrical signals.
Genetics: Genetics can play a role in developing arrhythmia. One way this can be seen is through mutations in a person’s DNA. They can potentially change the structure and function of the proteins necessary for the cardiac conduction system.

Reasons for Misdiagnosis

Arrhythmia is often misdiagnosed for a multitude of reasons.

The symptoms are commonly linked with conditions such as anxiety and panic attacks, and so they can be easily confused.
Furthermore, many types of arrhythmia are paroxysmal*, so maybe won’t show up on an ECG*.
Some types of arrhythmia (silent atrial fibrillation) display no physical symptoms; therefore, the condition is revealed during exams or after the patient has experienced a seizure or sudden cardiac death.

Treatments

For tachycardia (fast heartbeat), a range of medications can be used, such as beta blockers, adenosine, potassium and sodium channel blockers. Adenosine temporarily blocks any electrical signals travelling through the atrioventricular (AV) node and essentially resets your heart. This allows for a normal rate and rhythm to take over.
If medication doesn’t work, then more surgical options are favoured. This could include inserting a pacemaker, an implantable cardioverter defibrillator (ICDs), or even carrying out a procedure called catheter ablation*.

As we can see, arrhythmia isn’t just an irregular heartbeat. There is so much to this condition, including the different types of arrhythmia and how they each affect the body in different ways. Also, we can understand how treatments differ from one another to suit the different disorders that fall under arrhythmia.

*Paroxysmal - intermittent, they come and go.
*ECG - electrocardiogram. A test which records any electrical activity in your heart whilst also measuring the rate and rhythm of your heart.
*Ablation - In cardiology, ablation is a procedure to correct those irregular heartbeats.

Well, that’s the end of this article! If you enjoyed this blog or would like to suggest a topic, email Ishita (ishitakarvapalli6@gmail.com) or Aiza (aiza15spk@gmail.com).

As always, we would like to state that we are not doctors and are not writing these blogs as medical advice; they are designed solely to compile scientific knowledge and shed light on various medical conditions.