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by FireBeyond 2785 days ago
> A year before that, they announced face detection for the purposes of identity

Somewhat like Windows Hello, that also existed, based on technology from the Xbox Kinect?

> Two months ago, Apple announced an ECG sensor for your wrist.

Okay, so this is cool. But, putting on my paramedic hat for a moment, there is _SO_ much disinformation about what this does and what it is capable of detecting, what the difference is between FDA _clearance_ and _approval_, etc.

It can detect A-fib. This is a common, but usually not life threatening medical condition. It's good to have it diagnosed, but even undiagnosed, many people live happy lives blisfully unaware of it. Another way you can potentially recognize A-fib? It's not quite as fancy as the Apple Watch, though: put your fingers on your radial pulse by your wrist. Feel yourself skipping every fourth beat? That _could_ be a problem (though there are other diagnoses).

The Apple Watch does not and _cannot_ (despite ill-informed articles by Cnet and others) take the place of a "12 lead" ECG (random detail, in the medical field, ECG usually refers to an echocardiogram, an ultrasound imaging, and EKG, for electrocardiogram, is most commonly used for what the Apple Watch and other devices are doing).

From Cnet[1]: "Traditional EKG machines have 12 leads with electrodes that are attached all over your body to measure the electrical signals. Apple compares what the Apple Watch Series 4 does to a single-lead EKG, which research shows is just as effective at measuring the heart's electrical signals as a 12-lead machine."

This is flat out and factually wrong. The linked research shows nothing of the sort, and tries to walk someone through using a single lead system multiple times (up to 10), to get the full results of a 12 lead (if you've ever wondered why a 12 lead EKG only requires 10 physical leads, think of them more as 'axes', measured multiple ways, i.e. from lead 1 to lead 4, lead 1 to 5, etc), and then being able to aggregate them manually. For one, this requires moving the end points of the leads multiple times, something you could not do with the Apple Watch (or, to be clear and fair, any other watch), unless you're planning on holding it in many different spots in sequence (which then has issues of being more a time lapse, than a snapshot).

What does that mean? It can't diagnose impending heart attacks, nor heart disease, valve problems, circulatory disorders, and it likely never will, especially with current hardware.

This is also why it's obtained FDA clearance, not approval. To use a metaphor, it's more like a fitness device on steroids, so to speak, with some minor overlap into general health. But not that much more.

[1]: https://www.cnet.com/how-to/apple-watch-ekg-what-is-ekg/

1 comments

Having said that, an incidental 1 lead EKG on a wrist that can be brought up to your primary care and cardiologist at a later date is a game-changer. In clinical practice we will often use a Holter monitor (4 lead wearable EKG) to look for paroxysmal atrial fibrillation, but having a passive monitor such as this on for months at a time will help doctors have more information regarding tachycardias like atrial fibrillation. I disagree profoundly with the assessment that the Apple Watch is just a glorified fitbit. (Source: medical resident)