Stethoscope app shows promise in tracking heart health:  App turns smartphones into electronic stethoscopes

Smartphones are beginning to have a real influence on the way we manage our day-to-day health, and one area they may have a significant impact is in monitoring our hearts.  A new study has demonstrated that an app designed to turn smartphones into electronic stethoscopes can capture reliable, quality recordings of user heartbeats across the population, which doctors can then use to remotely monitor progression of heart conditions.

The Echoes app is designed to perform the role of a traditional stethoscope.  Users simply place the phone’s microphone directly on their skin in a quiet environment, with an onscreen slider enabling them to tune the microphone’s sensitivity to ensure they capture their beating heart.  The app was launched last May (2022) and has since gathered more than 100,000 heart recordings.  These are added to a database for scientists at Kings College London and the Maastricht University in the Netherlands to analyze for sound quality and try to spot clinical markers of cardiac events.

In newly published research, the scientists assessed more than 7,500 recordings, along with data on users’ gender, age, body mass index (BMI) and phone hardware.  While the team found that success rate of good recordings tended to decrease with user age, their gender, BMI or phone hardware did not alter the quality of the recordings.  “This research proves that mobile technologies are a viable way of recording heart sounds and that in the future, cardiac patients and doctors could use at-home recordings to check for existence or progression of heart conditions,” said Lead Researcher, Professor Pablo Lamata.

As a sign of how things are developing in smartphone diagnostics and heart health, in 2015 we looked at a related technology that performed as well as traditional stethoscopes.  However, rather than using the phone’s onboard microphone, the technology relied on an additional recording device that was placed against the patient’s skin and wired into an iPhone’s headphone jack.  In having the entire phone do the legwork on its own, the Echoes app could bring this functionality to everyday users.  The team says more work is needed to explore how the app can work with existing heart monitoring solutions; however, are excited about the possibilities.

“Our study has answered the central question to large-scale applications of using a smartphone microphone as a stethoscope,” said study Author Hongxing Luo, from Maastricht University.  “The results have shown that non-medical users are able to record heart sounds in sufficiently good quality for further processing of the signals.  We may be able to extract further features for diagnosis and monitoring purposes in future clinical studies.”

The research was published in the European Heart Journal 0 Digital Health.