Devices: Smarter stethoscopes

As an engineer with a passion for medicine, Connor Landgraf (B.S.’13, M.Eng.’14 BioE) started designing digital enhancements for stethoscopes as an undergraduate. With guidance from bioengineering professor Amy Herr, Landgraf continued this work with fellow master of engineering students Jiarong Fu, Zhengda Zhao and Robert Sibilia (all M.Eng.’14 BioE), as the team’s capstone project.

Digitally enhanced smart stethoscopeProblem

According to Landgraf, up to 80 percent of new primary care physicians don’t receive enough training to accurately diagnose common heart problems with standard “analog” stethoscopes. Existing audio-amplification devices for stethoscopes are pricey and unpopular with physicians, many of whom prefer classic stethoscopes.


The team took a two-pronged approach to making classic stethoscopes smarter. First, they designed a Bluetooth-enabled hardware device, which is placed between the stethoscope bell and the rubber tubing delivering sound to a clinician’s ears. A slender conical attachment amplifies and digitizes heart sounds, recording an audio clip and sending it, along with a waveform image, to a secure, cloud-based server via a smartphone.

This makes findings easy to process through the second tool Landgraf’s team is developing: a proprietary algorithm able to discern the difference between normal and abnormal heart sounds. This will provide what Landgraf calls “real-time decision support.”


This hardware-software-database combo has the potential to save lives and eliminate billions of dollars a year in unnecessary spending on cardiology referrals and electrocardiograms. A study in the British Journal of Cardiology in 2001 found that up to 60 percent of cardiology referrals were based on erroneous diagnoses, a figure the team aims to drastically reduce.

In 2013, the smart stethoscope team joined Berkeley’s SkyDeck incubator and named their venture Eko (pronounced “echo”) Devices. They anticipate FDA approval this fall. Meanwhile, a local hospital is beta-testing the device.

Update: Connor Landgraf and his fellow Eko Devices cofounders were named to Forbes magazine's 30 Under 30: Healthcare list of young game changers, movers and makers for 2015.

Topics: Bioengineering, Devices & inventions, Health, Alumni

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