Auscultation of arteriovenous fistula (AVF) using a smartphone

[Background] Monitoring of sounds emanating from an arteriovenous fistula (AVF) is of significant importance in clinical settings. The widespread use of smartphones, with over 80％ of the Japanese population utilizing them, presents an opportunity to use their recording capabilities for this purpose. Certain smartphones, such as iOSⓇ, are equipped with a recording application that is accessible through the settings. This study explores the potential use of smartphones to monitor AVF sounds and their efficacy in clinical settings. [Method] AVF sounds were recorded pre- and post-percutaneous transluminal angioplasty (PTA) using smartphones. The recording was made by positioning the bottom of the smartphone above the anastomosis of the shunt or at the palpable thrill site. [Results] The AVF sounds of three patients were successfully recorded. The volume of the AVF sounds post-PTA was louder than that during pre-PTA. The sound quality was similar to that of auscultation. [ Conclusion] Smartphones may be a reliable alternative to stethoscopes for the auscultation of AVF sounds.