2019
Heart sound segmentation using bidirectional LSTMs with attention
IEEE Journal of Biomedical and Health Informatics, vol. 24, no. 6
Fernando, Ghaemmaghami, Denman, Sridharan, Hussain, Fookes
A morning with BeatAware takes less time than the kettle.
Sit up, rest the bottom edge of the phone on your chest, and stay still for twenty seconds. The app listens, sends the recording for analysis, and comes back with one sentence and the numbers behind it.
Just left of centre, a hand's width below the collarbone.
Rest the bottom edge of the phone there, pointing out from your body. The phone tells you when it can hear your heart clearly, before the count starts. Thin fabric is fine.
Hold still. The field turns teal when the signal is good.
Talking or moving restarts the count, so the recording that leaves the phone is a clean one.
One sentence, one colour, and the numbers beneath.
Teal when this morning sits inside your usual range, amber when it sits outside it. Nothing shouts.
No cuff. No strap. No second device.
The microphone already in your iPhone can hear the two sounds every heartbeat makes. BeatAware turns that recording into heart rate, the timing of each beat and an estimate of blood pressure, and compares all of it with your own history rather than a population chart.
BeatAware is a wellness app, not a medical device. Its estimates are something for you and your doctor to talk about, not a diagnosis.
Blood pressure, estimated from the sound
Shown as pending until the analysis has beats it is confident about.
Heart rate and the cardiac cycle
Beats a minute, and how long each S1, systole, S2 and diastole lasted.
Your own usual range
Formed from seven readings over four weeks, then kept up to date.
What the microphone hears.
Every heartbeat makes two sounds. The first, S1, is the mitral and tricuspid valves closing as the heart begins to squeeze. The second, S2, is the aortic and pulmonary valves closing as it relaxes. Between them is systole; after them, the longer diastole. Move across the trace to read the phases.
S1
Illustrative trace and timings, not a real recording.
An electrocardiogram draws the electrical signal
It is the right tool for rhythm. It says nothing directly about the valves or the pressure the heart is working against.
A phonocardiogram records the mechanical event
The sounds are the valves themselves. Their timing and shape change with how the heart is filling, squeezing and relaxing, which is why clinicians have listened with a stethoscope for two hundred years.
A phone can record one
A modern iPhone microphone, with the bottom edge of the phone resting on the chest, captures the sounds at a quality the analysis can work with. The technology page follows the recording from microphone to sentence.
Measured against you, not against everyone.
A single reading is a data point. The product is what changes over weeks. After seven readings in four weeks the app knows your usual range for blood pressure and heart rate, and every morning after that is read against it.
Usual
This morning sits inside the band your own readings have drawn. The field is teal.
Higher, or lower
This morning sits outside it. The field is amber, and the copy says so plainly. It never advises care; that is a conversation for you and your doctor.
No verdict yet
The first week, a morning not yet recorded, a recording still being analysed. The field is slate.
Teal, amber and slate are the only colours in the app that mean anything. Nothing else is coloured for decoration.
Everything you see, you can hand to your doctor.
Each session keeps its recording, its beats and its numbers. Share one with your cardiologist, send a PDF report for any date range, or export every recording and result you have ever made.
Clinicians have a console of their own for patients, recordings and reports, and a REST API behind it. See Developers.
Built on published work on body sounds going back to 2009.
The team behind BeatAware has published in IEEE journals on finding the heart sounds in a recording, on models that explain which part of a sound they are reacting to, on lung sounds, and on audio analysis that stays reliable in noise. Three of the papers most relevant to the app:
2020
A robust interpretable deep learning classifier for heart anomaly detection without segmentation
IEEE Journal of Biomedical and Health Informatics, vol. 25, no. 6
Dissanayake, Fernando, Denman, Sridharan, Ghaemmaghami, Fookes
2017
Automatic segmentation and classification of cardiac cycles using deep learning and a wireless electronic stethoscope
IEEE Life Sciences Conference
Ghaemmaghami, Hussain, Tran, Carey, Hussain, Syed, Sinskey, O'Hashi, Sperling
Private by design.
A heart recording is health information. The app treats it that way, and says so in plain language in its own Privacy and consent screen.
The microphone, only while you record
Twenty seconds at a time, and the live level is on screen while it listens.
Stored under your account
Each recording and its results are kept by the BeatAware service so they follow you between phones. Your date of birth and sex are used only to set your usual range.
Shared only when you share
A session goes to your cardiologist, a report goes where you send it, and an export goes to you. Nothing else leaves without an action of yours.
Yours to export or delete
Export every recording and result, or delete your account and its data, from the Profile tab.
Questions people ask.
Is BeatAware a medical device?
No. BeatAware is a wellness app. It describes how this morning compares with your own usual and shows you the measurements behind that. It does not diagnose, treat or prevent any condition, and it does not replace advice from a qualified health professional.
How can a phone estimate blood pressure from sound?
The timing and shape of the two heart sounds change with the pressure the heart is working against. The analysis service measures every accepted beat and estimates systolic and diastolic pressure per beat with a confidence; the app shows the estimate only when enough beats carry one, and marks it pending otherwise.
Which phones work?
BeatAware is an iPhone app. An iPhone 13 or newer records best. An Android version is on the way.
When can I use it?
The iPhone app is in early access through TestFlight, Apple's app for trying software before it is released. Leave your name and email at the top of this page and we will send an invitation as places open.