Overview
A rapid heart could be a concerning situation depending on the nature of the medical problem causing it. In this article, we will try to look at the definition of normal and rapid heart rate, the symptoms, and causes of accelerated heart rate, and what are some complications that can arise as a result of this phenomenon.
What is your heart rate?
Have you ever had a doctor put their fingers over your wrist to feel for something; What they are measuring is known as Heart Rate also known as a pulse which is essentially the number of times your heart beats per minute. A heartbeat is generated when the chambers of the heart (known as the atria and ventricles) contract as a result of electrical signals which are stimulated and initiated by the pacemaker or sinoatrial node located in right atrium (one of the heart chambers).1
How fast is a rapid heart rate?
Normal resting heart rate ranges from 60-100 beats per minute,2 if this rate exceeds 100 beats per minute at rest, this would be considered a rapid heart rate or Tachycardia.
How to measure heart rate
So, if you want to measure your heart rate, you can do so easily:4
- First, begin by placing the index fingers on the wrist of your opposite hand at the base of the thumb
- Alternatively, place your fingers below the jawbone at the side of the neck
- Measure the number of beats in 15 seconds and then multiply by 4, this will be your heart rate
Symptoms of a fast heart rate
There are many symptoms of tachycardia which include:3
- Fainting (medically referred to as syncope)
- Palpitations (thumping feeling in the chest of a fast heartbeat)
- Shortness of breath
- Fatigue
- Chest pain/tightness
In more severe cases, one can experience cardiac arrest
Causes of tachycardia
Different forms of tachycardias have different causes. Let’s look at each one of them in detail:
Sinus tachycardia
This happens when the pacemaker initiates and fires electrical signals faster than usual leading to a normal increase in heart rate. Even though the heart rate is faster, it is still beating in a regular cardiac rhythm. This usually occurs in response to physiological distress (for example strenuous exercise or excessive stress). It can also occur due to anxiety, fear, or fever.3
Inappropriate sinus tachycardia
Essentially, this means that the heart is beating faster than normal without a known reason. It is stipulated, however, that the nerves that control the heart rate do not work as intended giving rise to this effect. It could also arise from a virus.5
Atrial or supraventricular tachycardia
Tachycardia can occur due to the misfiring of signals (abnormal electrical signals) in the atria (the upper chambers of the heart) and hence the phenomenon can also specifically be referred to as atrial or supraventricular tachycardia. This misfiring interferes with the natural signals coming from the sinoatrial node. This disruption in the normal heart rhythm then causes a rapid increase in heart rate.3
Ventricular tachycardia
Ventricular Tachycardia (also known as V-Tach) occurs due to the irregular beating and resultant pumping of the ventricles (the lower chambers of the heart) leading to the body not receiving adequate oxygenated blood.
There are a few causes behind V-Tach:6
- Structural issues in the heart:
- Heart Attack
- Heart Failure
- Inflammation of the heart muscle (myocarditis)
- Issues with heart valves
2. Idiopathic ventricular tachycardia:
The term idiopathic means that the origin of a disease or condition is unknown or that the illness is spontaneous. IVT can therefore occur when cells outside the pacemaker of the heart begin to initiate an electrical signal and start interfering with the normal cardiac rhythm.
3. Genetic causes – catecholaminergic polymorphic ventricular tachycardia
A serious genetic illness, it can cause the ventricles to beat rapidly leading to potential fainting and even death due to inadequate blood supply to the body.
When to go to hospital
If you have any of the symptoms listed above, it is pertinent that you visit your healthcare provider immediately. The symptoms are similar across most types of tachycardia so it would be important to know if you have a serious issue. At the hospital, one of the first things that your physician might do is conduct an Electrocardiogram (ECG ) – a simple test where sensors are attached to your skin to determine if your heart’s rhythm and electrical conductivity are in order.7
Complications
Atrial Fibrillation
This is essentially a type of Supraventricular Tachycardia that involves the atria stimulating electrical impulses erratically which causes the muscles in the atrium to twitch or quiver – hence the name fibrillation. This phenomenon may present intermittently too, in which case it is called paroxysmal atrial fibrillation. While the condition is not life-threatening it is considered very serious because it can give rise to blood clots and cause strokes.8
Atrial flutter
This is a type of SVT too and is very similar to Atrial Fibrillation, but the symptoms are milder, Atrial Fibrillation but it is possible for an individual to have both conditions.8
Heart failure symptoms
If you compare the symptoms of tachycardia and heart failure, you will notice some overlap which underlines the importance of getting yourself checked out by your doctor as soon as possible. The primary symptoms of heart failure, according to the NHS (National Health Service, UK), include:9
- Severe shortness of breath after moderate activity or even at rest
- Fatigue
- Loss of consciousness/dizziness/fainting
- Swollen ankles
- Unexplained/unintentional weight loss
- A rapid heart
Treatments
Just like the cause, the treatment for tachycardia depends on the type of tachycardia.
Treatment for Inappropriate Sinus Tachycardia would involve removing any potential stimulants that may increase heart rate; your doctors may also prescribe you medicines to slow down your heart rate and will probably recommend that you exercise, as per your ability, to stay healthy.5
Supraventricular Tachycardia is not usually life-threatening but in case you need to go to the hospital, your physician might prescribe you medicine to keep the condition under control. In more severe cases, one of the following methods may be used:10
- Cardioversion: Electric shock that is given to the heart to loop back into normal rhythm
- Catheter ablation: in this procedure, thin tubes are placed in the heart through an artery or vein to rectify the problems with the electrical conductivity of the heart. This usually fixes the problem(s) permanently
Ventricular Tachycardia is usually treated using medications or catheter ablation. However, a device known as an implantable cardioverter defibrillator can be also placed inside the patient’s heart which delivers an electrical pulse in scenarios when there is a dangerous, rapid, and irregular heartbeat.6
Prevention
Prevention of tachycardia would mostly involve maintaining a healthy lifestyle which includes doing regular exercise (as much as you can handle) and keeping a healthy and nutritious diet.
Summary
In conclusion, therefore, the heartbeat originates from a group of cells in one of the upper chambers of the heart (right atrium) which then gives rise to a heart rate. A rapid heart is known as tachycardia and depending on the type can have multiple causes and varying symptoms. Tachycardia can be related to heart failure too so if you have any of the symptoms, it will be best to seek advice from your physician to rule out any serious conditions.
References:
- How the Heart Works - How the Heart Beats | NHLBI, NIH [Internet]. www.nhlbi.nih.gov. Available from: https://www.nhlbi.nih.gov/health/heart/heart-beats
- American Heart Association. All about heart rate (pulse) [Internet]. American Heart Association. 2015. Available from: https://www.heart.org/en/health-topics/high-blood-pressure/the-facts-about-high-blood-pressure/all-about-heart-rate-pulse
- American Heart Association. Tachycardia: Fast Heart Rate [Internet]. www.heart.org. 2016. Available from: https://www.heart.org/en/health-topics/arrhythmia/about-arrhythmia/tachycardia--fast-heart-rate
- Harvard Health Publishing. Want to check your heart rate? Here’s how - Harvard Health [Internet]. Harvard Health. Harvard Health; 2018. Available from: https://www.health.harvard.edu/heart-health/want-to-check-your-heart-rate-heres-how
- Articles [Internet]. Cedars-Sinai. Available from: https://www.cedars-sinai.org/health-library/diseases-and-conditions/i/inappropriate-sinus-tachycardia.html
- Ventricular Tachycardia [Internet]. 2019. Available from: https://www.hopkinsmedicine.org/health/conditions-and-diseases/ventricular-tachycardia
- National Health Service. Electrocardiogram (ECG) [Internet]. NHS. 2021. Available from: https://www.nhs.uk/conditions/electrocardiogram/
- British Heart Foundation. Atrial fibrillation [Internet]. Bhf.org.uk. 2019. Available from: https://www.bhf.org.uk/informationsupport/conditions/atrial-fibrillation
- NHS. Heart failure - Symptoms [Internet]. nhs.uk. 2017. Available from: https://www.nhs.uk/conditions/heart-failure/symptoms/
- NHS Choices. Supraventricular tachycardia (SVT) [Internet]. Nhs. 2019. Available from: https://www.nhs.uk/conditions/supraventricular-tachycardia-svt/