Heart Sounds (Digital Stethoscope)

What it does

Heart Sounds reads phonocardiogram recordings made with a digital stethoscope at the standard auscultation sites: aortic, pulmonary, tricuspid and mitral. Each recording is segmented into heart cycles, with the first and second heart sounds located, before any murmur is assessed.

The run returns heart rate, S1 and S2 timing, whether a murmur is present, absent or cannot be judged, its timing (systolic or diastolic), the site where it is heard best and its grade, the quality of each recording, and an estimated probability of structural heart disease that helps prioritise echocardiography. The result ends with guidance on echo referral.

Intended use

Decision support for clinicians who auscultate and have to decide who needs an echocardiogram: screening of children for congenital heart disease, where most murmurs are innocent, and of adults for valve disease.

Who it is for

General practitioners, paediatricians, nurses and community health workers who use digital stethoscopes, and the cardiologists and paediatric cardiologists who receive their referrals. Telemedicine services can attach the same structured read to remote auscultation.

Accepted input

• Audio: WAV files from a digital stethoscope, one file per auscultation site, one to four sites per run.
• DICOM: General Audio Waveform objects carrying the same recordings.
• Patient data: age, sex, height and weight with each upload.

Requirements

Requirement	Why
One file per site, labelled with its site	Murmur location and the site of maximal intensity
Several complete heart cycles per recording	S1/S2 segmentation and timing need repeated cycles
Quiet recording with steady contact	Speech, crying, breathing and friction noise mask murmurs
Age, sex, height and weight	The structural heart disease risk uses them alongside the sounds

Recordings that are too noisy to judge are reported as such, and a murmur is then returned as unknown rather than absent.

Optional context

The reason for auscultation, known heart disease and previous echo findings can be passed in clinical_context.

The result

One structured result per patient with per-site findings, heart rate, segmentation and a quality rating for each recording; the cycles that show the murmur are marked on the returned waveform.

Section	Content
Murmur	Present, absent or unknown; systolic or diastolic timing; sites where it is heard; grade
Structural heart disease risk	Estimated probability of an abnormal cardiac evaluation, mainly for children, with an echo-referral recommendation
Draft report	Opt-in (options.report): an English narrative that interprets the result for the reader (findings, impression, limitations); every number is checked against the findings

Standards

• DICOM: results reference the General Audio Waveform recordings they were computed from.
• Guidance: a positive murmur or an elevated risk points to a transthoracic echocardiogram, which MedRun can read with its echocardiography model.

Evidence notes

The structural heart disease risk is designed mainly for paediatric screening. Heart rate and S1/S2 timing come from the segmentation of each recording and are shown per site.