What can cause arrhythmias of the heart?

While it is normal for your heartbeat to speed up or slow down on occasion, an abnormal heart rate or rhythm may sometimes indicate arrhythmia.

Here to provide an expert insight into arrhythmia, including types, causes and treatment, is Dr Senthil Kirubakaran, renowned consultant cardiologist and electrophysiologist based in Portsmouth.

What is an arrhythmia?

An arrhythmia is an abnormal rhythm of the heart.

A normal heart rhythm, or heartbeat, is generated by electrical impulses passing through the chambers of the heart in a coordinated and controlled manner. If this is disrupted in any way, it will cause an abnormal rhythm of the heart, called an arrhythmia.

What are the different types of arrhythmia?

Broadly speaking, there are three types of arrhythmia:

• Slow rhythms of the heart, called bradyarrhythmia or bradycardia
• Fast rhythms of the heart, called tachyarrhythmia or tachycardia
• An irregular heartbeat, which are usually extra beats or ectopic beats (skipped beats) of the heart

Can arrhythmia range from mild to serious?

Arrhythmia can certainly range from mild to serious. However, this depends on the type of rhythm disturbance in question.

With slow rhythms of the heart, these can cause people to have syncope if left untreated.

With fast rhythms of the heart, the severity of the arrhythmia depends on where the abnormal rhythm is coming from. Rhythms from the main pump of the heart (the ventricles), for example, tend to be more serious. If left untreated, they can cause problems in the future.

With other rhythms of the heart, such as extra beats or ectopic beats, these tend to be benign and very mild.

Besides these, there is a separate group of rhythms of the heart that tend to be in the middle of the spectrum in terms of severity, causing a moderate risk. However, again, it depends on the specific type of rhythm.

What causes or triggers arrhythmias?

The causes of different rhythm disturbances are varied.

With slow rhythms of the heart, these tend to happen as a consequence of the heart not generating electrical impulses properly, or, due to the failure of electrical impulses passing through the heart. This tends to occur as people grow older, when nerves and electrical impulses start to slow down. Thus, slow rhythms of the heart are conditions that usually affect the elderly population more.

With fast rhythms of the heart, these can have a number of different causes and triggers. Some rhythms happen in childhood and are associated with extra nerves in the heart, leading to supraventricular tachycardia. Other rhythms of the heart, however, occur as a consequence of damage to the heart itself due to other cardiac conditions, such as heart attacks that can cause scars in the heart. These scars can predispose people to ventricular rhythms of the heart later on.

In terms of triggers, again, this is very varied and it also depends on the type of rhythm disturbance. There are some rhythms that can happen with exercise or stress, whilst there are other rhythms that happen in the middle of the night. At the same time, there are some rhythms of the heart that occur sporadically, causing significant impact to a person’s quality of life due to the sporadic nature and the unpredictability of the rhythm.

How are arrhythmias treated? Is surgery always required?

Different rhythm disturbances require different treatment options. If the rhythm itself is benign and very mild then, certainly, the rhythm can be left alone and monitored over time.

Some rhythm disturbances require specific treatment in the form of drugs to help keep the rhythm of the heart as normal as possible. There are many drugs available, particularly for fast rhythms of the heart or extra beats, that can certainly do this and improve quality of life at the same time.

Other rhythm disturbances require specific intervention, such as surgical procedures, to try and correct them. Slow rhythms of the heart, for example, can be treated with pacemakers if they are causing symptoms.

Other rhythms of the heart, particularly fast rhythms of the heart, can be treated with ablation. This is a cardiac procedure that targets and treats the actual area in the heart that is causing the rhythm disturbance, either with radiofrequency or with freezing technologies.

However, I would generally say that not all rhythm disturbances need interventional procedures. In fact, I would say that it is rare for rhythm disturbances to require surgical procedures. Interventions tend to be reserved for those rhythm disturbances that cause significant problems to a person’s quality of life.

What happens if arrhythmia is left untreated?

Slow rhythms of the heart that are left untreated can result in people having syncope, due to the heart not being able to pump blood properly to the brain. Thus, treatment for slow rhythms of the heart is usually recommended as soon as people start developing symptoms. This is generally in the form of a pacemaker.

Milder rhythms of the heart, such as extra beats or ectopic beats, that are left untreated will not cause any problems at all.

Some fast rhythms of the heart that are left untreated, however, can result in the muscle of the heart becoming weak. This can lead to cardiac conditions, such as heart failure, which can become problematic in the future.

As well as these, there are obviously some very serious rhythms of the heart that can cause severe complications if left untreated. These rhythms usually arise from the ventricles of the heart.

Again, the type of rhythm disturbance will determine as to whether it requires treatment or not.

Dr Senthil Kirubakaran is a renowned consultant cardiologist and electrophysiologist with over 20 years’ experience.

If you require expert assessment and management for cardiac arrhythmias, do not hesitate to visit Dr Kirubakaran’s Top Doctors profile today.