Hiroto visits his doctor after experiencing shortness of breath while playing basketball. to record his heart rate, the doctor recommends he use a(n) digital laboratory. electronic medical chart. heart rate monitor. medical camera.

Heart rate monitor

Explanation:

A heart rate monitor is a type of medical device which can be used personally  to measure and display the heart rate in real time.

It is basically used to monitor the heart rate at the time of physical exercises. It can be referred as electrocardiography.

If Hirato is feeling shortness of breathe while playing basket ball then he should use heart rate monitor to to keep a watch on his real time heart rate.