TOPLINE:

An analysis of heart sounds measured using a smartphone-based application (FonoCheck) showed efficacy in screening people for atrial fibrillation (AF) in community settings, with a positive predictive value of 94% when the condition was confirmed through ECG.

METHODOLOGY:

  • Researchers investigated whether heart sounds measured by smartphones can facilitate screening for AF in community settings.
  • They prospectively enrolled 5312 participants (mean age, 53 years; 60% women) from two districts in China between August 2023 and May 2024.
  • A smartphone was placed on the apical auscultation area of the chest of participants, and an app recorded heart sounds for 30 seconds.
  • Heart sounds in the range of 20-150 Hz were visually assessed in a software based on irregularities in rhythm and variability of amplitude; participants with suspected AF were followed up for ECG-based confirmation.
  • A random sample of 20% of participants aged 65 years or older who showed no indications of AF on the basis of heart sounds served as the negative control group.

TAKEAWAY:

  • Visual assessment of heart sounds identified 39 cases of suspected AF; the proportion of cases of suspected AF determined from heart sounds increased with age (P P = .04).
  • Follow-up ECG confirmed AF in 34 cases, yielding a 94% positive predictive value; the prevalence of AF increased with age (P
  • None of the participants from the negative control group had a confirmed diagnosis of AF.
  • The app recorded 270 (5%) noisy heart sounds, and these recordings were excluded from all analyses.

IN PRACTICE:

“The high positive predictive value and the low rate of noisy heart sound recordings (5%) support the FonoCheck app as a reliable tool for AF detection in community populations,” the researchers reported. “The performance is comparable to other AF screening methods using wearable devices, such as smartwatches. The app may be more easily accepted by physicians because heart sounds have long been an integral part of bedside examinations vs other apps that use smartphone camera-based photoplethysmography technologies.”

SOURCE:

This study was led by Huiying Ren, MD, of Southeast University in Nanjing, China. It was published online on July 28, 2025, in Circulation.

LIMITATIONS:

The true prevalence of AF may have been underestimated as only those with suspected arrhythmias and a proportion of elderly participants underwent diagnostic follow-up, potentially missing paroxysmal AF. Measurement of heart sounds may require validation in hospital settings with simultaneous ECGs. 

DISCLOSURES:

This study received grants and institutional and provincial funds from multiple agencies, including the National Natural Science Foundation of China, the Excellent Young Scientists Fund Program Overseas 2022, and the Jiangsu Shuangchuang Project.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.