: A Prospective Study Investigating the Use of the Eko CORE and Eko DUO Electronic Stethoscopes in Pediatric Patients.


The Eko CORE and DUO stethoscopes are FDA approved electronic devices which have the capacity to record heart sounds. This study will utilize these devices to see if they can differentiate between pathologic and innocent heart murmurs in children.

Full Title of Study: “A Prospective Study Investigating the Use of the Eko CORE and Eko DUO Electronic Stethoscopes for Differentiation of Innocent vs. Pathologic Murmurs in Pediatric Patients.”

Study Type

  • Study Type: Observational
  • Study Design
    • Time Perspective: Prospective
  • Study Primary Completion Date: February 2021

Detailed Description

It is estimated that 50-70% of all children will have had a detectable heart murmur at some point in early life, but fortunately, the vast majority of these murmurs are benign asymptomatic "innocent" murmurs and not indicative of heart disease. However, there is concern about the ability of front-line pediatricians and family providers to distinguish between an innocent and pathological murmur. Thus, it is of no surprise that the largest number of new patient referrals to pediatric cardiologists is due to the detection of a murmur. Of those referred, 20-30% are typically diagnosed with trivial to significant heart disease based on auscultation and confirmatory echocardiography follow-up when necessary.

Having a child referred for a heart murmur evaluation causes significant anxiety for parents, even if the murmur is suggested to be innocent by the pediatrician and in some cases, clinical diagnostic testing is done unnecessarily. Interestingly, studies have shown that performing diagnostic electrocardiography, chest radiography, or echocardiography prior to clinical assessment by pediatric cardiologists did not offer additional assistance in differentiating murmurs. Unnecessary echocardiograms or other diagnostic tests for innocent murmur evaluation add unnecessary cost to the healthcare system.

Unfortunately, the unnecessary use of echocardiography for the diagnosis of innocent murmurs is also high among pediatric cardiologists. Thus, with the rising cost of health care, it is essential that we identify and target areas of practice that will enable us to increase efficiency and reduce unnecessary costs.

Specific characteristics of the sound of the murmur may help differentiate innocent from other murmurs, so improving auscultation skills and diagnosis based on auscultation and electrocardiography is very important in accurate diagnosis and reducing cost associated with the diagnosis of innocent and pathologic heart murmurs in children. The use of new technologies to improve auscultation and auscultation-based diagnosis could lead to improved diagnoses with decreased cost. New systems that used telemedicine techniques to transfer phonocardiogram (PCG) recordings to a cloud server have shown benefit in differentiating innocent versus pathologic murmurs, but cannot be used large scale, and are based on cardiology involvement.

The FDA-cleared Eko CORE device (Eko, Berkeley, California, USA) is a digital stethoscope that allows recording of the audio to produce a PCG. The FDA-cleared Eko DUO device is a digital stethoscope that allows recording of the audio to produce a PCG combined with a single lead electrocardiograph. The CORE and DUO both feature sound amplification and audio transmission to a smart phone, laptop or tablet via Bluetooth® that allows the user to open and playback sounds using an iOS, Android, or Microsoft Windows compatible application. The App provides the ability to save sounds within select Electronic Health Record (EHR) systems, share patient recordings with other practitioners, and annotate notes on recorded audio. Eko is intended for use on pediatric and adult patients. These features uniquely situate this device to accumulate large sets of auscultatory data on patients both with and without congenital heart disease (CHD).

In this study, we seek to use auscultatory audio recordings and phonocardiograms collected from pediatric patients using Eko CORE and DUO digital stethoscopes to develop a clinically significant algorithm that differentiates innocent from pathologic heart murmurs. As the Eko CORE and DUO devices are similar to a traditional stethoscope, an iconic tool widely accepted by patients and providers alike, its use to drive an automated detection algorithm is both feasible and attractive as a substitute for traditional auscultation. Furthermore, by providing an algorithmic analysis that can supplement clinical acumen, we hypothesize that we will improve overall diagnostic accuracy and show a decreased need for referral echocardiograms for innocent murmurs.


  • Device: Use of EKO Core and EKO Duo electronic stethoscopes
    • Listen to heart murmurs

Clinical Trial Outcome Measures

Primary Measures

  • Comparison of stethoscope recordings between innocent, pathologic and none to determine if stethoscope can differentiate
    • Time Frame: Recording 2 minutes of heart sounds for each stethoscope
    • The data science team will generate ROC curves for algorithm scores in the set of recorded heart sounds. Exploratory descriptive analyses of the algorithm will be performed by identifying clinical correlates to the characteristics most heavily weighted in detecting a pathologic murmur. The likelihood ratios of the test at sensitivity cut offs of 0.90, 0.95, 0.99 will also be determined. Patients will also be stratified based on age as a secondary outcome: For example, infants (0<1 years of age, since murmurs in this age group are more likely to be pathologic), young children (1-5 years of age), children (>5-12 years of age) and adolescents (>12 to<18 years of age). Murmurs will be classified as none, innocent [defined as no significant heart disease on echocardiogram and further classified as Still's, pulmonary flow murmur, systemic flow murmur, venous hums by the physician], or pathological by disease type (e.g., atrial septal defect (ASD), ventricular septal defect (VSD), etc.

Secondary Measures

  • Murmurs identified by stethoscope recording will be stratified based on age
    • Time Frame: 2 minutes of recording with two stethoscopes
    • Differentiated murmurs of infants between 0-1 years, young children, ages 1-5 years, children ages >5-12 years and adolescents >12 years < 18 years will be evaluated and murmurs identified

Participating in This Clinical Trial

Inclusion Criteria

1. Patients aged 0 to 17 years, who are able to read and speak English, and/or with parents or legal guardians who are able to read and speak English

2. New patients referred to the Nemours Cardiac Center for a heart murmur, chest pain, syncope, or arrhythmia. This could include children with suspected murmurs (but ultimately found to have no murmur by a cardiologist), innocent murmurs, and pathologic murmurs.

3. Patients with previously diagnosed heart condition, if they have not had any corrective surgeries and had a detectable murmur at their last clinic visit (for pathological and innocent murmurs) or had no detectable murmur at their last clinic visit (for no murmurs).

Exclusion Criteria

1. Patients aged 18 and over

2. Patients and/or parents who are unable to read or speak English

3. Patients who have had corrective heart surgery for a heart defect

4. Auscultation cannot be performed properly at all locations

5. Patients not wishing to participate in study recordings

Gender Eligibility: All

Minimum Age: N/A

Maximum Age: 18 Years

Are Healthy Volunteers Accepted: Accepts Healthy Volunteers

Investigator Details

  • Lead Sponsor
    • Nemours Children’s Clinic
  • Provider of Information About this Clinical Study
    • Sponsor
  • Overall Official(s)
    • Nicholas Slamon, MD, Principal Investigator, Nemours/Alfred I duPont Hospital for Children
  • Overall Contact(s)
    • Catherine M Haut, DNP, 3026515161, Catherine.haut@nemours.org


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