suggested reading (Score 1)

There are many books out there that cover ecg circuit design, one of which is Medical Instumentation by Webster which discusses the topic ad nausea.

One of my undergrad bioengineering advisors told about the droves of electrical engineering undergrads that came to him year after year. The students thought intro circuit design was all they needed to build competent medical equipment, yet they had never even heard of isolation. I just thought it was funny that they probably did zero research and kept re-inventing the wheel.