Design and development of an electronic stethoscope for cardiac murmur identification

Abstract

Cardiac murmurs are the sounds produced by the abnormal passage of the blood flow inside the heart due to the diseased value of tissues. Identifying the type of the murmur can diagnose the cardiac pathology related to that particular murmur. This paper describes a researched digital stethoscope that can be used as a stethoscope as well as a murmur identification device. To capture the heart beat, a chest piece of a traditional stethoscope is used with a condenser microphone attachment. Then the signal is amplified and filters out the noise and sent to the microprocessor. At the processing module, amplifying is carried out and stores the sampled data if the data transmission is not being done. then the amplified data is transmitted to a central location using radio frequency transformer module to carry out the signal processing. If the user wishes, the signal processing can be done in the stethoscope itself since the microprocessor is in the stethoscope unit. Auto correlation has been used as the signal processing algorithm.