Analytics Stories

CHAPTER 30Can We Predict Heart Attacks in Real Time?

One out of four deaths in the United States is caused by heart attacks (see www.cdc.gov/heartdisease/facts.htm). Are we near the time when your smartwatch will sense that you are high risk for a heart attack and text you to go to the hospital before the heart attack occurs? Unfortunately, as of April 2020, we are not close to realizing this goal. In this chapter, we will discuss the Apple Heart Study, which is (hopefully) a first step toward accurate prediction of the likelihood that a participant will suffer a heart attack (if not treated) in the near future.

Smartwatches such as the Apple Watch have an optical heart sensor that can continuously monitor a user's heart rate and heart rate variability (see med.stanford.edu/news/all-news/2019/11/through-apple-heart-study--stanford-medicine-researchers-show-we.html). Every several hours, the watch creates a plot (a tachogram) that shows the time between heartbeats. Beginning with WatchOS 5.1.2, the owner of the watch can sign up for the Apple Heart Study and receive a notice of potential arrhythmia (irregular heartbeat) if five of the last six tachograms indicate an irregular heartbeat. Atrial fibrillation and atrial flutter (AF) are two types of irregular heartbeats. The presence of AF increases the risk of a stroke 500%, and it is estimated that 700,000 people have AF and don't know it. With these facts in mind, Apple and Stanford University cooperated in the Apple Heart Study, ...