Apple Watch has powerful sensors that make it the ultimate device for a healthy life. Now with new notifications and the ECG app, it can provide you and your patients with important information concerning their heart health.
Apple Watch checks for unusually high or low heart rates in the background, which could be signs of a serious underlying condition. This could help you and your patients identify situations which may warrant further evaluation.
If a patient’s heart rate is above 120 bpm or below 40 bpm while they appear to have been inactive for 10 minutes, the user will receive a notification. Patients can adjust the threshold bpm or turn these notifications on or off. All heart rate notifications — along with date, time and heart rate — can be viewed in the Health app on iPhone.
The irregular rhythm notification occasionally checks for signs of irregular rhythms that may be suggestive of atrial fibrillation (AFib). This feature won’t detect all instances of AFib but may catch something that can provide your patients with an early indication that further evaluation may be warranted.
Irregular rhythm notifications use the optical heart sensor to detect the pulse wave at the wrist and look for variability in beat‑to‑beat intervals when the user is at rest. If the algorithm repeatedly detects an irregular rhythm suggestive of AFib, your patient will receive a notification and the date, time and beat‑to‑beat heart rate will be recorded in the Health app.
With the ECG app on Apple Watch Series 4, patients who experience symptoms such as rapid or skipped heartbeat, or receive the irregular rhythm notification, can capture an ECG and record their symptoms. This real-world data can enable you to make more informed and timely decisions regarding further evaluation and care.
The ECG app uses the electrical heart sensor built into the Digital Crown and the back crystal of Apple Watch Series 4 to record a single lead ECG similar to a Lead I ECG. The ECG app then provides a result of sinus rhythm, atrial fibrillation or inconclusive, and prompts the user to enter any symptoms such as rapid or pounding heartbeat, dizziness or fatigue. The waveform, results, date, time and any symptoms are recorded and can be exported from the Health app as a PDF to share with a clinician. If the patient notes symptoms that indicate a serious condition, they are prompted to immediately call emergency services.
The ECG app waveform is similar to a Lead I ECG, which can enable classification of atrial fibrillation and sinus rhythm, but cannot identify other conditions, like heart attacks.
After taking an ECG reading, the ECG app will check for sinus rhythm or AFib. If the heart rate is under 50 bpm or over 120 bpm, the app is unable to check for AFib, but will note the heart rate and save the ECG recording. The ECG app may provide an inconclusive result if, for example, there is poor signal due to motion artifacts or poor electrode contact, the heart rate is between 100 and 120 bpm, or for other reasons such as presence of arrhythmias other than AFib, presence of an ICD or pacemaker, or poor electrical signal in the recording which can occur as a result of right axis deviation.
In a clinical study, the rhythm classification by the ECG app of a single lead ECG on Apple Watch was compared to the rhythm classification by a cardiologist of a simultaneously collected 12-lead ECG. The ECG app demonstrated 99.6% specificity in classifying sinus rhythm and 98.3% sensitivity in classifying AFib for the classifiable results. In this study, 12.2% of recordings were not classifiable.
This can be an addition to our growing armamentarium to identify AFib, which can be intermittent and asymptomatic.
Products that seek to provide deeper health insights, like the Apple Watch, have the potential to be significant in new clinical care models and shared decision making between people and their healthcare providers.
Apple is democratizing healthcare, providing on‑demand access to accurate sensors and software that can help consumers develop real healthcare literacy and inform how daily choices impact their health.
*Note: Original Apple Watch does not support these functions
When a hard fall is detected with Apple Watch Series 4, an alert appears and allows the user to easily call emergency services or dismiss the alert. If the user is unresponsive for about a minute, an emergency call will be placed automatically and a message will be sent to the user’s emergency contacts. All falls detected are recorded in the Health app. This feature is automatically enabled for users 65 years and older and can be turned on for anyone in the Apple Watch app on iPhone.
Medical ID allows first responders and emergency room clinicians to access critical medical information from a patient’s iPhone lock screen or Apple Watch without requiring a passcode, and without compromising patient privacy. Patients can list important information such as allergies, medications, conditions, organ donor preferences and emergency contacts by setting up Medical ID in the Health app on iPhone.
When a user’s iPhone is locked with a passcode, Touch ID or Face ID, their health data in the Health app is encrypted on‑device. If a user chooses to sync their health data with iCloud, it is encrypted while in transit and at rest.