Rapid heart rate (medical term: tachycardia) is a potentially serious symptom that can lead to serious health conditions such as stroke, heart failure, cardiac arrest, and sudden cardiac death. 

Please continue reading to learn some of the signs and symptoms of tachycardia and when to seek emergency treatment for a fast heart rate. 

What is the normal heart rate?

According to the American Heart Association, a resting heart rate between 60 and 100 beats/minute is considered normal in adults. A heart rate slower than 60 beats/minute is called bradycardia, and a heart rate faster than 100 beats per minute is called tachycardia. 

Tachycardia (fast heart rate) is a normal response in certain situations, such as during exercise or stressful situations. It can also occur due to an abnormal heart rhythm.

Similarly, bradycardia (slow heart rate) can occur when you’re sleeping, and this is normal. Athletes can also have normal heart rates below 60 beats/minute.

How can I locate my pulse to measure my heart rate?

The best place to measure your pulse is at the carotid artery in your neck. You can find this artery by placing two fingers below the angle of your jaw on one side of your windpipe. You can also find your pulse at the radial artery on your wrist on the side of the thumb. 

How do I measure my heart rate?

To measure an accurate heart rate, count the number of beats for 60 seconds. You can also count the beats for 30 seconds and multiply by two. So, for example, if you count 40 beats in 30 seconds, your heart rate is 80 beats/minute. 

What are the signs and symptoms of a rapid heart rate?

To know whether you have a rapid heart rate, you can time your pulse as explained above. This will tell you whether you are in the normal heartbeat range (60-100 beats/minute) or tachycardic (over 100 beats/minute). 

A rapid heart rate can also cause other symptoms. The following signs and symptoms may accompany a fast heart rate:

• Heart palpitations (a feeling that your heart is racing or pounding)
• A fluttering or flopping sensation in the chest
• Dizziness
• Lightheadedness
• Fainting
• Chest pain
• Shortness of breath
• Loss of consciousness

When to go to the emergency room for a rapid heart rate?

You should call 911 or go to the emergency department if a rapid heart rate is accompanied by chest pain, difficulty breathing, dizziness, fainting or near fainting, or loss of consciousness.

Most heart palpitations are caused by stress, anxiety, or too much alcohol, caffeine, or nicotine. However, if you feel your heart racing or your resting heart rate is consistently above the normal range, make an appointment to see your primary care doctor. If needed, your doctor will refer you to board-certified physicians who specialize in cardiology.

It is important to see a healthcare provider for a physical exam because some types of abnormal heart rhythm, such as atrial fibrillation, if left untreated, can increase your risk of developing blood clots, which puts you at risk of heart attack and stroke. 

What to do if someone has stopped breathing or has no pulse?

Some types of tachycardia can cause a sudden drop in blood pressure, causing the person to lose consciousness and collapse within seconds. If this occurs and you can’t find a pulse or heartbeat, do the following:

• First, call 911.
• Next, if you are trained in CPR, start CPR. 
• If you’re not trained in CPR and are not sure how to give rescue breaths, perform hands-only CPR by pushing down hard firmly on the center of the person’s chest at a rate of approximately 100-120 times a minute until EMS arrives.
• If there is an automated external defibrillator (AED) available, follow the instructions on the device. You can use an AED without any prior training. This device can deliver an electrical shock to reset the heart’s rhythm to a normal rhythm. The device will only deliver the electrical shock if it’s needed.

What causes rapid heart rate?

The heart beats faster or slower in response to various situations and environmental factors. Some of the things that can cause a rapid heart rate include:

• Exercise
• Emotional stress
• Sympathetic nervous system activation (fight or flight response)
• Fever
• Dehydration
• Low blood sugar
• Low or high blood pressure
• Hyperthyroidism (overactive thyroid)
• Anemia (low red blood cells)
• Electrolyte imbalance 
• Heavy alcohol use 
• High caffeine consumption
• Smoking
• Recreational drugs, specifically stimulants like methamphetamine or cocaine
• Medication side effects

An increased heart rate can also be caused by abnormal heart rhythm.

Types of Irregular Heart Rhythms

Different types of abnormal heart rhythms can cause a fast heart rate. They are described briefly below.

• Sinus tachycardia is the increase in heartbeats due to exercise or stress.
• Atrial fibrillation or A-fib is a common type of tachycardia due to irregular or erratic electrical signals in the heart’s upper chambers (atria).
• Atrial flutter is similar to A-fib but less chaotic. The same person can have atrial fibrillation at times and atrial flutter at other times.
• Ventricular tachycardia starts in the heart’s lower chambers (ventricles). Longer episodes of ventricular tachycardia are potentially life-threatening.
• Supraventricular tachycardia (SVT) refers to abnormal heart rhythms that originate above the ventricles. These types of palpitations occur in abrupt episodes. 
• Premature ventricular complexes (PVCs) are extra heartbeats that originate in the ventricles and cause a sensation of skipping beats or fluttering in the chest.
• Ventricular fibrillation is a condition in which there are fast, erratic electrical signals in the ventricles. This is a serious problem and can be fatal if the heart rhythm isn't reset within minutes. 

How can I prevent my heart beating fast?

If your fast heartbeats are due to other medical conditions, such as coronary artery disease or congestive heart failure, it may not be possible to prevent them without managing heart failure or treating your heart disease.

The best way to prevent tachycardia and maintain a regular rhythm is to optimize your heart health. You can do this by leading a healthy lifestyle:

• Eat a heart-healthy diet
• Exercise regularly
• Maintain a healthy weight
• Keep blood sugar and cholesterol numbers in check
• Stop smoking
• Drink alcohol in moderation
• Don’t use illegal drugs

References:

1. https://www.mayoclinic.org/diseases-conditions/tachycardia/symptoms-causes/syc-20355127