If a racing heart is waking you from sleep, this can be even scarier than PVCs.

When you’re sleeping, your body is at its lowest energy needs, so why would your heart suddenly start racing?

What awakens you is the sudden racing of your heart, provided that you’re not in a deep sleep.

Any deviation from the normal minimal state that your body is in can be enough to pull you out of slumber.

Of course, when that deviation is a racing heart, and you’re just lying there in the middle of the night in a dark room, this can be quite alarming.

Racing Heart vs. Palpitations

that Awaken You

Let’s first make sure that what you’re experiencing is indeed a racing heartbeat, rather than palpitations or premature ventricular contractions.

They are not one and the same. A rapid pulse can still consist of a smooth rhythm, while PVCs may occur amid a normal pulse speed.

This article is not about thumping, fluttering, jumping, “skipped” or erratic heartbeats.

It’s strictly about an increase in heart rate. Sinus tachycardia means a fast heart rate but a normal rhythm.

Causes of Awakening from Sleep

with a Racing Heart

“This is most commonly caused by anxiety that could result from underlying stress or a bad dream,” says Morton Tavel, MD, Clinical Professor Emeritus of Medicine, Indiana University School of Medicine, and author of “Health Tips, Myths and Tricks: A Physician’s Advice.”

• Side effects of medications like those for cold, or asthma inhalers

• High caffeine intake before bedtime

• Drop in blood pressure while asleep—the heart speeds up to compensate to make sure there’s enough blood circulating throughout your body. Causes are many including pregnancy.

• Drop in blood sugar—again, the heart speeds up to compensate. Causes include strenuous exercise with inadequate recovery nutrition.

• Hyperthyroidism (overactive thyroid), though you’ll likely have additional symptoms like unintentional weight loss or feeling hot when nobody else in the room does.

•  “A less likely cause would a heart rhythm disorder that results in an inappropriately rapid rate,” says Dr. Tavel.

“In this latter case, the problem is usually benign and often resolves spontaneously.”

The condition is called supraventricular tachycardia, of which there are several types.

People who have this are primarily young adults. It can last minutes to hours and be accompanied by a tight chest and feeling breathless.

Dr. Tavel also explains, “In some instances, it can be terminated by vigorous coughing or by breath-holding combined with bearing down (similar to motion during defecation).

“If it doesn’t stop within about 20-30 minutes, medical attention should be sought promptly.”

• Atrial fibrillation—you may feel no other symptoms than a fast heart rate that awakens you from sleep, but other symptoms may be chest pain and a faint feeling while awake. Untreated A-fib is a risk factor for stroke.

Panicking after you realize that a racing heart has awakened you from sleep may speed up your pulse and/or prolong the racing.

Rather than fret over this the following day, make an appointment with a cardiologist.

Do not be scared of test results. Often, the patient is told he’s just fine. But there’s only one way to find out for sure!

morton tavel, MD

Dr. Tavel’s medical research includes over 125 publications, editorials and book reviews in peer-reviewed national medical journals. He was formerly director of the cardiac rehabilitation program at St. Vincent Hospital in Indiana.
Sources:
patient.info/blogs/sarah-says/2013/06/abnormal-heart-rhythms—getting-to-the-heart-of-the-matter
heart.org/HEARTORG/Conditions/Arrhythmia/AboutArrhythmia/Tachycardia-Fast-Heart-Rate_UCM_302018_Article.jsp#.WHVNe1MrLxM