What would cause heart rate to drop

Condition Basics

What is bradycardia?

Having bradycardia (say "bray-dee-KAR-dee-uh") means that your heart beats very slowly. For most adults, a heart rate of about 60 to 100 beats a minute while at rest is considered normal. If your heart beats less than 60 times a minute, it is slower than normal.

Table of Contents Show

Condition Basics
What is bradycardia?
What causes it?
What are the symptoms?
How is it diagnosed?
How is bradycardia treated?
How can you care for yourself?
Sinus bradycardia
Medications
What causes sudden heart rate drop?
Should I be worried about my heart rate dropping?
When should I go to the ER for low heart rate?

A slow heart rate can be normal and healthy. Or it could be a sign of a problem with the heart's electrical system.

For some people, a slow heart rate does not cause any problems. It can be a sign of being very fit. Healthy young adults and athletes often have heart rates of less than 60 beats a minute.

In other people, bradycardia is a sign of a problem with the heart's electrical system. It means that the heart's natural pacemaker isn't working right or that the electrical pathways of the heart are disrupted. Sometimes, the heart beats so slowly that it doesn't pump enough blood to meet the body's needs. This can cause symptoms, such as feeling dizzy or weak. In some cases, it can be life-threatening.

What causes it?

Bradycardia can be caused by many things. Examples include:

Changes in the heart that are the result of aging.
Diseases that damage the heart's electrical system. These include coronary artery disease, heart attack, and infections such as endocarditis and myocarditis.
Conditions that can slow electrical impulses through the heart. Examples include having a low thyroid level (hypothyroidism) or an electrolyte imbalance, such as too much potassium in the blood.
Many types of medicines. Examples include antidepressants, heart medicines, and opioids.

What are the symptoms?

A very slow heart rate may cause you to:

Feel dizzy or light-headed.
Feel short of breath and find it harder to exercise.
Feel tired.
Have chest pain or a feeling that your heart is pounding or fluttering (palpitations).
Feel confused or have trouble concentrating.
Faint, if a slow heart rate causes a drop in blood pressure.

Some people don't have symptoms, or their symptoms are so mild that they think they are just part of getting older.

You can find out how fast your heart is beating by taking your pulse. If your heartbeat is slow or uneven, talk to your doctor.

How is it diagnosed?

To diagnose bradycardia, your doctor may take your pulse, do a physical examination, ask questions about your health, and do an electrocardiogram (EKG or ECG). An EKG measures the electrical signals that control heart rhythm.

Bradycardia often comes and goes, so a standard EKG done in the doctor's office may not find it. An EKG can identify bradycardia only if you have it during the test.

You may need to wear or carry a device called a portable, or ambulatory, electrocardiogram. Examples include a Holter monitor and a cardiac event monitor. You might use it for a day or more. It records your heart rhythm while you go about your daily routine.

You may have blood tests to find out if another problem is causing your slow heart rate.

How is bradycardia treated?

How bradycardia is treated depends on what is causing it. Treatment also depends on the symptoms. If bradycardia doesn't cause symptoms, it may not be treated. You and your doctor can decide what treatment is right for you.

If damage to the heart's electrical system causes your heart to beat too slowly, you will probably need to have a pacemaker. A pacemaker is an implanted device that helps correct the slow heart rate.
If another medical problem, such as hypothyroidism or an electrolyte imbalance, is causing a slow heart rate, treating that problem may cure the bradycardia.
If a medicine is causing your heart to beat too slowly, your doctor may adjust the dose or prescribe a different medicine.

The goal of treatment is to raise your heart rate and relieve symptoms. For certain types of bradycardia, treatment may help prevent serious problems. These problems include fainting, injuries from fainting, and even death.

How can you care for yourself?

Bradycardia is often the result of another heart condition, so taking steps to live a heart-healthy lifestyle will usually improve your overall health. The steps include:

Having a heart-healthy eating plan that includes vegetables, fruits, nuts, beans, lean meat, fish, and whole grains. Limit alcohol, sodium, and sugar.
Being active on most, if not all, days of the week. Your doctor can tell you what level of exercise is safe for you.
Losing weight if you need to, and staying at a healthy weight.
Not smoking.
Managing other health problems, such as high blood pressure, high cholesterol, and diabetes.

Your heart rate is the number of times your heart beats in 1 minute and is a measure of cardiac activity. Most healthy adults have a heart rate between 60 and 100 beats per minute when they’re at rest.

Bradycardia happens when your heart rate is slower than normal. While it’s possible for some healthy individuals to have a slow heart rate, a heart that’s beating slower than normal may also be an indication of a medical problem.

Keep reading to learn more about bradycardia, what causes it, and how it’s treated.

You have bradycardia when your heart rate is slower than 60 beats per minute at rest.

In some cases, a slow heart rate is an indication of an extremely healthy heart. Athletes, for instance, often have lower than normal resting heart rates because their heart is strong and doesn’t have to work as hard to pump blood throughout the body.

Your heart rate can also slow down when you’re in a deep sleep. During this time, it’s not unusual for your heart rate to drop below 60 beats per minute.

Having a slower heart rate, however, can also be a sign of something more serious.

A heart rate that’s too slow can mean that not enough oxygen-rich blood is reaching the organs and tissues in your body. This can affect your body’s ability to effectively carry out its normal processes and functions.

Many people with bradycardia don’t have any noticeable symptoms. When symptoms are present, they may include:

fatigue
weakness
shortness of breath
spells of dizziness or lightheadedness
near-fainting or fainting
exercise intolerance, which is when you tire quickly during physical activity

If you’re having symptoms consistent with bradycardia, see a doctor. They can help determine what may be causing your symptoms.

Recognizing a potential emergency situation
In certain situations, a slow heart rate could indicate a medical emergency. The following bradycardia symptoms may be a sign of a more serious condition:
chest pain
trouble breathing
pallor (pale skin)
cyanosis (bluish skin color)
blurred or hazy vision
trouble focusing or concentrating
disorientation
confusion
near fainting or loss of consciousness
If you have any of these symptoms and a change in your heart rate, call 911 or seek emergency medical attention immediately.

It’s possible for bradycardia to happen due to damage to the heart muscle. When this occurs, it can interfere with the electrical signaling that coordinates your heartbeat.

Some examples of heart-related conditions that may lead to the development of bradycardia include:

coronary artery disease, a condition where blood flow to the arteries of the heart is impaired
heart attack, in which blood flow to the heart is cut off, causing heart muscle to die
previous surgery to the heart
congenital heart conditions, which are abnormalities in the heart that are present from birth
myocarditis, a swelling of the heart muscle that may be caused by infections or autoimmune disease
pericarditis, a condition that involves inflammation of the sac surrounding your heart
rheumatic fever, a potential complication of strep throat, that can lead to heart issues
damage to the heart’s electrical system from prior infection or inflammation

There are also several additional underlying conditions that may lead to bradycardia. These include:

an electrolyte imbalance, most specifically an imbalance of calcium or potassium
hypothyroidism, which happens when your thyroid produces too little thyroid hormone
sleep apnea, a condition where your breathing pauses when you’re asleep

Additionally, some medications may cause bradycardia as a side effect. A few examples include:

blood pressure medications like beta-blockers and certain calcium channel blockers
some types of anti-arrythmic drugs
opioids

Sinus bradycardia

The sinoatrial (SA) node is your heart’s natural pacemaker. It initiates the electrical impulses that travel through your heart muscle, resulting in your heartbeat.

When your SA node sends out electrical impulses at a slower rate, it’s called sinus bradycardia.

Sinus bradycardia can happen naturally due to the aging process. It can also occur due to several of the factors discussed above, including:

damage to your heart muscle due to conditions such as a heart attack, a pervious heart surgery, or myocarditis
congenital heart conditions
health conditions like hypothyroidism or sleep apnea
side effects from certain medications

A thorough medical evaluation by a healthcare professional is necessary to determine the cause of a slow heart rate. This will typically include the following:

a thorough medical history
a physical examination, which will include measurement of your vital signs, including your heart rate, blood pressure, and respiratory rate
an electrocardiogram (EKG or ECG), which measures the electrical activity in your heart

Based on the findings from the evaluation above, it’s possible that your doctor may recommend additional testing, such as:

laboratory tests, which may include tests of blood glucose, electrolyte levels, or thyroid function
an echocardiogram, which uses ultrasound technology to create pictures of your heart
Holter monitoring, which measures the electrical activity of your heart while you go about your daily activities
a sleep study to determine if you have sleep apnea that may be contributing to your bradycardia

The treatment of bradycardia depends on what’s causing it. Bradycardia that’s mild or occasional may not require treatment.

If a slow heart rate is due to the effect of a medication, it’s possible that your doctor may adjust your medication dosage. If possible, they could also switch you to a different medication that doesn’t have bradycardia as a side effect.

Similarly, if an underlying condition is contributing to your bradycardia, your doctor will work to address that condition. For example, the medication levothyroxine can be used to manage hypothyroidism.

It’s also possible that your doctor may recommend a pacemaker. This is an implanted medical device that stimulates heartbeats so that they occur at a regular rate and rhythm. Bradycardia is one of the main conditions for which a pacemaker may be recommended.

Medications

There are also a few medications that may be used to treat bradycardia. These may be utilized when bradycardia is causing acute symptoms and isn’t due to a reversible cause, such as a medication side effect.

Medications for bradycardia work to increase your heart rate and can include:

atropine, which is the first-line drug treatment for bradycardia
dopamine
epinephrine
glycopyrrolate

All of these medications are given via intravenous (IV) infusion. If they’re not effective at managing acute symptoms of bradycardia, temporary pacing (either transcutaneous or transvenous) may be used to ease bradycardia.

COVID-19 is the illness that’s caused by the novel coronavirus, SARS-CoV-2. There are several potential cardiovascular symptoms associated with COVID-19, one of which is bradycardia.

It’s still unclear what exactly causes this symptom in individuals with COVID-19, but it may be due to one or a combination of the following factors:

direct damage to the heart muscle
the body’s inflammatory response
low oxygen levels in the body (hypoxia)
a drop in blood pressure (hypotension)

Currently, most of the availablereports about bradycardia in COVID-19 have been in individuals that have been hospitalized. It’s unclear whether this symptom appears in people who aren’t hospitalized and, if so, how frequently it happens.

The reports on how bradycardia during COVID-19 is treated can vary. While some individuals had bradycardia that resolved on its own, others required a temporary or permanent pacemaker.

If you’re curious about your heart rate, you can measure it yourself. First, find your pulse by holding a finger (not your thumb) to the radial artery on the inside of your wrist. Then, count the number of beats per minute while you’re resting.

Other places your heart rate can be measured include:

on your neck, alongside your windpipe (carotid artery)
inside your elbow (brachial artery)
on the inside of your groin/upper thigh (femoral artery)
on the top of your foot (pedal pulse)

When you’re determining your heart rate, here are some numbers to keep in mind:

A resting adult heart rate is normally between 60 to 100 beats per minute.
Athletes or people on certain medications may have a lower-than-normal resting heart rate.
The normal heart rates for children can be different from those of adults, depending on a child’s age:
- up to 3 months old: 85 to 205 beats per minute
- 3 months to 2 years: 100 to 190 beats per minute
- 2 to 10 years: 60 to 140 beats per minute
- older than 10 years: 60 to 100 beats per minute

Bradycardia is when your heart rate is too slow. It can be caused by a variety of conditions, particularly those that can impact the heart’s normal electrical signaling. If you have bradycardia, your body may not be receiving enough oxygen to carry out its normal functions.

Some people with bradycardia may not have any noticeable symptoms. However, others may experience fatigue, weakness, or shortness of breath. In serious cases, chest pain, confusion, and loss of consciousness can occur.

Bradycardia can be effectively managed through treatments that address what’s causing it. Make an appointment with your doctor if you notice any changes in your heart rate, especially if the changes are accompanied by other symptoms.

What causes sudden heart rate drop?

Ventricular fibrillation These erratic electrical impulses, sometimes triggered by a heart attack, cause your heart's ventricles to quiver. When you have this kind of arrhythmia, your ventricles can't pump blood into your body, and your heart rate drops quickly.

Should I be worried about my heart rate dropping?

If you have bradycardia, your heart beats fewer than 60 times a minute. Bradycardia can be a serious problem if the heart rate is very slow and the heart can't pump enough oxygen-rich blood to the body. If this happens, you may feel dizzy, very tired or weak, and short of breath.

When should I go to the ER for low heart rate?

Adults and children who have a low pulse and experience symptoms such as chest pain, fainting, or exercise intolerance should also go to the hospital. A person should contact a doctor about bradycardia when they: experience an unexplained change in heart rate that lasts for several days.