Now, 'simulated' human heart to screen drugs

In a breakthrough, a British scientist has developed a new technique that uses beating heart muscles to test safety of drugs, eliminating the need for human or animal trials.
The work by Dr Helen Maddock from the Coventry University in UK could lead to the lives of hundreds of future patients being saved and the quality of their treatments improved.
Adverse effects of drugs on the cardiovascular system are a major cause of many medical treatments failing, but heart-related side-effects can often only be detected once a drug is being used on patients in clinical trials - by which time it is too late.

Maddock's 'in vitro' technique - which means 'in glass' in reference to it taking place in a laboratory environment rather than in a living organism - uses a specimen of human heart tissue attached to a rig allowing the muscle to be lengthened and shortened whilst being stimulated by an electrical impulse, mimicking the biomechanical performance of cardiac muscle.
Trial drugs can then be added to the tissue to determine whether or not they have an adverse effect on the force of contraction of the muscle (and therefore of the heart), a test that could only previously be performed 'in vivo'- ie on living animals - often with inconclusive results.

This 'simulated' cardiovascular system - known as a work-loop assay - provides the most realistic model of heart muscle dynamics in the world to date, and opens up unprecedented possibilities for identifying negative effects of drugs early and inexpensively - potentially saving lives and speeding up the development of successful drug treatments.

"I'm delighted that our research is at a stage where we can confidently say the work-loop assay we've created is the world's only clinically relevant in vitro human model of cardiac contractility," Maddock, who spent almost ten years developing the technique, said.
"It has the potential to shave years off the development of successful drugs for a range of treatments," Maddock said.

"Both the pharma industry and regulators recognise that existing methods of assessing the contractility of the heart are fraught with problems, so we're incredibly excited to be able to introduce a new way to accurately determine the safety of drugs in respect of the heart without the need to test on humans or animals," said Maddock.