Scientists at the University of Michigan's have developed a testing chip that mimics your heart rhythm to know the drugs, which will behave properly under the stresses of your body.
The device uses microscopic, gravity-powered fluid channels to replicate heartbeats and other natural flows (such as brain signals).
You'll know if that treatment works properly when the patient's heart is racing, for example. You don't need to stick around pumping fluid yourself unlike previous attempts at emulating heartbeats. Long-term tests that reflect what would happen in a real body over time can be done.
Researchers can use this chip much sooner than other experimental medical tech, since it's only going to be used in the lab. The University expects to share the design with other scientists in a matter of months though there are no plans to sell it. If you end up needing heart medicine in the future, you may well get drugs that are genuinely in tune with the way your body works.