Apple Watch Series 4 and later model is getting ECG feature in India. The feature is being rolled out as part of watchOS 6 update, which became available yesterday night. The update brings the new ECG app and irregular heart rhythm notification feature. Since it became available globally last year, the feature has helped users identify signs of AFib, the most common form of irregular rhythm. The announcement comes at a time when the burden of atrial fibrillation (AFib) has become an important health issue in India.
“We are confident in the ability of these features to help users have more informed conversations with their physicians,” said Sumbul Desai, MD, Apple’s Vice President of Health. “With the ECG app and irregular rhythm notification feature, customers can now better understand aspects of their heart health in a more meaningful way,” Desai added.
AFib can lead to blood clot formation in the heart, leading to stroke. It is more prone in those patients who are predisposed to having AFib and stroke. Apple Watch Series 4 or later come with new electrodes built into the back crystal and Digital Crown. They work together with the ECG app to enable customers to take an ECG similar to a single-lead reading.
In order to take an ECG at any time or following an irregular rhythm notification, users of Apple Watch Series 4 or later need to open the new ECG app and hold their finger on the Digital Crown. As the user touches the Digital Crown, the circuit is completed and electrical signals across their heart are measured. After 30 seconds, the heart rhythm is classified as either AFib, sinus rhythm or inconclusive. All recordings, their associated classifications and any noted symptoms are stored securely in the Health app on iPhone.
Apple Watch Series 4 or later users can then share a PDF of the results with their physicians. With watchOS 6, the irregular rhythm notification feature will use the optical heart sensor to occasionally check the user’s heart rhythm in the background for signals of an irregular heart rhythm that appears to be Afib.
If irregular heart rhythm such as Afib is identified on five rhythm checks over a minimum of 65 minutes, a notification will be generated to alert the user. The ability of ECG app to accurately classify an ECG recording into AFib and sinus rhythm was validated in a clinical trial of around 600 participants. The study found the ECG app on Apple Watch demonstrated 98.3 percent sensitivity in classifying AFib and 99.6 percent specificity in classifying sinus rhythm in classifiable recordings.
The irregular rhythm notification feature was recently studied in the Apple Heart Study. With over 400,000 participants, the Apple Heart Study was the largest screening study on atrial fibrillation ever conducted. A subset of the data from the Apple Heart Study was submitted to the FDA to support clearance of the irregular rhythm notification feature. In that sub-study, of the participants that received an irregular rhythm notification on their Apple Watch while simultaneously wearing an ECG patch, 80 percent showed AFib on the ECG patch and 98 percent showed AFib or other clinically relevant arrhythmia.
There have been several examples where Apple Watch saved lives. A US doctor saved a person’s life by using Apple Watch Series 4 on his wrist to detect atrial fibrillation at a restaurant. An Apple Watch user in the UK was recently alerted about his low heart rate by the device. It revealed a serious heart condition that ultimately resulted in a surgery to fix the problem.
There is a dearth of data on epidemiologic outcomes in patients of Afib in India, leading to inconsistent practice patterns as regards to medical therapy, and Apple Watch data can help in this direction, feel experts. According to Dr Devi Shetty, Chairman and Executive Director of Narayana Health, devices like Apple Watch will help users have better conversations with their doctors. “It will open the door for a big shift in monitoring an individual’s heart health,” said Shetty.
(Written with IANS inputs)