Fast Heart Rate and Lightheaded

After your physician determines the cause, and prescribes an appropriate treatment plan, you can use that guidance to create a lifestyle that promotes good heart health.
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If you've ever experienced a heart racing and lightheaded feeling, it can certainly be a cause for concern. After your physician determines the cause, and prescribes an appropriate treatment plan, you can use that guidance to create a lifestyle that promotes good heart health.


Fast Heart Rate Causes

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Maybe your pulse has recently been a bit elevated, and you can't figure out the reason behind this higher-than-normal reading.

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A normal heartbeat rate is 60 to 100 times per minute, according to the U.S. National Library of Medicine. If you exercise often, or take medicines that decrease your heart rate, your heart may beat less than 55 beats per minute. A heart rate that's over 100 beats per minute is classified as tachycardia, while a slow heart rate is known as bradycardia.

According to Dr. Richard Lee of Harvard Medical School, there are several possible causes for a fast heart rate. If you're otherwise healthy, a fast heart rate isn't a cause for concern unless it's regularly higher than 100 beats per minute in a resting state. A 120-beats-per-minute rate deserves further investigation, but is not necessarily dangerous.

If you do have a higher-than-normal heart rate, there can be several non-cardiac reasons for it. Fast heart rate causes include a fever, an overactive thyroid gland and anemia. Anxiety, caffeine overconsumption or excessive decongestant use can also be at fault.


Less-than-optimum physical conditioning could be another of the fast heart rate causes. If you show a high-normal heart rate, and your doctor doesn't see evidence of a serious issue, they might recommend you ramp up your physical activity. By becoming more physically fit, your resting heart rate will gradually slow down.

If your heart rate regularly reads above 100 beats per minute, even when you're completely relaxed and immobile, you could potentially be affected by an abnormal heart rhythm. Your elevated rate could also result from a heart muscle weakened by a virus. As a result, your heart must beat faster to pump sufficient blood throughout your body.


Read more: What Is a Good Exercise Heart Rate?

Fast Heart Rate Diagnostic Tests

Your physician (or cardiac specialist) wants to determine if you're affected by tachycardia, explains the Mayo Clinic. This is a type of heart rhythm condition in which your heart has a higher-than-normal rate while you're resting.



Your doctor will perform one or more tests that are helpful in diagnosing tachycardia. An electrocardiogram (EKG or ECG) is a commonly performed test that uses small sensors attached to your arms and chest. These devices record your heart's electrical functions, which enables the doctor to find patterns that can help determine the tachycardia's source.

Your physician may also ask you to wear a portable EKG device that records your heart's activity for a certain period. A Holter monitor records heart function for 24 hours, while an event monitor records longer-term activity, but only for a few minutes at a time.


More Heart Rate Diagnostic Tools

An electrophysiological test involves use of electrode-tipped flexible catheters. Your physician inserts these small tubes into your blood vessels, and carefully guides them to different locations in your heart.

There, the devices record the path of each beat's electrical impulses. This intricate procedure can confirm your doctor's diagnosis or find the source of malfunctions in your heart's electrical circuits.


Cardiac imaging can reveal whether your heart has structural abnormalities that can help to cause the tachycardia. An echocardiogram uses sound waves to show your heart in motion.

A magnetic resonance imaging test (MRI) takes images of your heart's blood flow, while a computerized tomography (CT) scan provides a cross-sectional heart view. A coronary angiogram can display potential blood flow blockages. Finally, a standard chest X-ray can help to determine if you have an enlarged heart.


For an interactive stress test, electrodes monitor your heart's function while you perform a certain exercise, usually walking on a treadmill.


In certain cases, your physician may prescribe additional tests. These procedures can help to identify another condition that has contributed to the tachycardia's development.

Read more: The 14 Best Foods for Your Heart

Fast Heart Rate Treatment

If your physician discovers you're affected by tachycardia, and determines the cause, they'll create a fast heart rate treatment plan that should address the issue. According to Dr. Blair Halperin of the Providence St. Vincent Medical Center, there's more than one type of tachycardia.

First, you might have experienced common sinus tachycardia, which can result from exercise, stress, excitement or fear. Other tachycardia types fall into the arrhythmia category, and are essentially malfunctions of your heart's electrical system.

When a short-circuit occurs in the heart's two upper chambers (the atria), it's called atrial tachycardia. Electrical malfunctions in the two lower chambers (or ventricles) are known as ventricular tachycardia.

Fast heart rate treatment options will vary based on the tachycardia type. Your physician might perform a catheter ablation procedure, which permanently removes the tissue that caused the electrical pathway to short-circuit.

This procedure will likely correct the problem, and should eliminate the need for daily medicines that can carry notable side effects.

What Are Heart Palpitations?

If you feel like your heart is racing or pounding, or sense that your heart has skipped a few beats, you may be experiencing heart palpitations. The U.S. National Library of Medicine states that these palpitations, which usually aren't serious, can be caused by varied external factors.


Potential causes include stress, panic attacks, anxiety or fear. Use of caffeine, nicotine, diet pills and illegal drugs such as cocaine can also cause heart palpitations. They can be triggered by a fever or by engaging in exercise too.

Although most palpitations aren't cause for concern, that could change if they're accompanied by an arrhythmia, or abnormal heart rhythm. An arrhythmia can be caused by heart disease, abnormal blood potassium levels or a malfunctioning heart valve. Low blood oxygen levels, an overactive thyroid gland or specific medications are also potential sources. To determine the arrhythmia cause, your physician will likely prescribe one or more targeted tests.

If you're experiencing palpitations for the first time, tell your physician about the symptoms so you can receive proper treatment. However, certain symptoms require immediate medical attention, and potentially a trip to the emergency room. Experiencing your heart racing and light headed sensation are among them.

If you have chest pain, shortness of breath, abnormal sweating or dizziness, get medical help quickly. Feeling your heart racing and light headed and loss of consciousness are also red flags.

To reduce the chances that you'll be affected by heart palpitations, find ways to decrease anxiety and stress and begin a consistent exercise program. Engage in regular deep relaxation or breathing exercises.

Beginning a regular yoga, tai chi or meditation regimen may also be helpful. Decreasing your caffeine and nicotine usage, and avoiding smoking, is also beneficial.

After your doctor determines that the palpitations aren't due to a serious cause, try not to dwell on them, as that can be stressful. If you continue to have the palpitations, and notice that they change or become more frequent, see your doctor without delay.


Read more: Breakfast, Lunch, and Dinner on a Cardiac Diet

Can Heart Palpitations Cause Nausea?

Heart palpitations can be a sign of arrhythmia, or an abnormal heart rhythm, explains PeaceHealth Sacred Heart Medical Center at RiverBend. Although arrhythmia can occur without any symptoms, you could also experience well-defined symptoms that will likely get your attention.

Besides palpitations, other arrhythmia symptoms include a slow or rapid heartbeat. You could also feel a fluttering sensation, as if your heart skipped several beats in a row.

If you feel like you're ready to faint, you're having a pre-syncope episode. This condition can cause dizziness or lightheadedness, and tunnel or blurred vision might also occur. Headache, mental confusion and sweating are possible. Be prepared for potential nausea or a stomach ache as well.




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