Apple Watch Can Help Monitor Your Heart

Jeffrey L. Williams, MD

The Series 4 Apple Watch has just been announced and will prove to be a game changer for heart health monitoring. It is the first over-the-counter electrocardiogram product available direct to consumer.


It has three main features:

  • It will be able to automatically detect abnormally slow heart rhythms.
  • It can screen for heart rhythm disorders such as atrial fibrillation.
  • It has a built-in electrical sensor to take a single lead electrocardiogram (ECG) in less than 30 seconds.

The first two features are enabled by the optical sensor on the back of the Apple Watch. The final ECG feature is a novel sensor where the user touches the digital crown on the watch which then permits the electrical sensor on the back of the watch to record a single heart rhythm strip recording the electrical activity of the heart. The digital processor in the Apple Watch has algorithms to analyze the recording and provide an interpretation. This will permit the user to obtain a heart rhythm interpretation, such as normal sinus rhythm or atrial fibrillation. These ECG strips are saved in the user’s Digital Health iPhone application. These results can then be shared with your doctor at the next visit. This is analogous to the alerts from your car’s electrical monitoring system (such as the Check Engine light). It is important to discuss these findings with your care provider to see if there are any serious issues that need to be addressed.

What is a normal heart rhythm?

A normal heart rhythm is when your heart rate is between 60 and 100 beats per minute (bpm), with one atrial and one ventricular contraction for each heartbeat. This is called normal sinus rhythm. The sinus node is a specialized area in your heart that serves as the “timer” or “pacemaker” for your heart. Any heart rate above 100 bpm or below 60 bpm could be abnormal. However, there are some situations where a heart rate may be less than 60 bpm but not indicate an abnormality, such as in a well-trained athlete at rest; the most common situation is called sinus bradycardia, and no treatment is necessary. Similarly, there are some situations where a heart rate may be more than 100 bpm, such as during illness or infection; the most common explanation for this is called sinus tachycardia, and treatment of the underlying illness will correct the fast heart rhythm.

What are abnormal heart rhythms?

Abnormal heart rhythms include a multitude of situations in which the heart rate is outside the normal range of 60 to 100 bpm. Furthermore, an abnormal heart rhythm can also occur within the normal range of between 60 and 100 bpm. Another cause of abnormal heart rhythms is when the heart beats irregularly for any reason. Not all abnormal or irregular heart rhythms are worrisome or need treatment.

What are palpitations?

Palpitations are the sensation of an irregular, fast, uncomfortable, or strong heartbeat. These symptoms may be caused by an abnormal heart rhythm, but I have many patients with palpitations that are not associated with any arrhythmia. It is important to note that many patients will not experience palpitations but still have an arrhythmia. Finally, not all patients with “palpitations” have a heart-rhythm abnormality; this can be very frustrating for the patient, but we can at least offer reassurance that there is not an active cardiac issue.

Other symptoms that may represent heart-rhythm abnormalities.

My goal as a care provider for heart-rhythm disorders is to carefully listen to the patient describing his or her symptoms and determine the likelihood that these symptoms may represent a heart-rhythm abnormality. Many patients who have an arrhythmia will not tell me that they are “having a fast heartbeat.” Often, patients report fluttering, vibrating, skipping, or tingling. Furthermore, patients may not experience these symptoms in the chest but instead experience symptoms in the stomach, neck, jaw or back. I have had a patient report belching; careful questioning revealed that the patient had a heart-rhythm abnormality that caused her to feel nauseous and start belching!

As the American College of Cardiology President C. Michael Valentine says, “There are several sub-groups of patients that could benefit from this new device. While there are many digital recording devices on the market today, a wearable device for the wrist is obviously easier for most patients – especially a device that could better track patients who have more intermittent symptoms of arrhythmia.”

About the Author

Jeffrey L. Williams, MD, FACC, FHRS, is an Electrophysiologist and Cardiologist with Lakeland Regional Health. He serves as Assistant Quality and Medical Informatics Officer for Lakeland Regional Health. In addition, Dr. Williams has authored several books on cardiovascular issues. Call 863-284-5020 to make an appointment with Dr. Williams.