Heart Spark is a heart-shaped pendant which flashes little lights (light emitting diodes, LEDs) in time with your heart beat.
This video shows how it works:
"Les Archives du Cœur", by Christian Boltanski, permanently houses recordings of the heartbeats of people throughout the world. Christian Boltanski has been recording these heartbeats since 2008. Les Archives du Cœur is a testament to the recordees' existence. The recordings may be listened to by visitors. It is also possible to record your own heart beat here.
http://www.designboom.com/art/christian-boltanski-the-heart-archive/
http://benesse-artsite.jp/en/art/boltanski.html
almost same idea...!
■ Pulse Sensor by SparkFun.
■ Single Lead Heart Rate Monitor - AD8232 by SparkFun
- this is interesting to read https://learn.sparkfun.com/tutorials/ad8232-heart-rate-monitor-hookup-guide?_ga=1.161604794.782366639.1459701888
Mozzi is sound synthesis library for Arduino.