Table 1.

Relative advantages and disadvantages of drug testing using animal experimentation, isolated cardiac tissues, and engineered cardiac tissues

Parameter	Animal experiments	Isolated cardiac tissues	Engineered cardiac tissues
Advantages	Integrate complexity of whole organism Allow long-term studies Identify effects of metabolites Validity (effects in animals are “real”) Full repertoire of genetic manipulation Long-term experiences Regulatory demand	Direct access to cardiac muscle or vessel function Intact mature myocardium/vessel Full repertoire of methods to determine function Long-term experiences	Human Direct access Simple interventions Stability for days/weeks Simple genetic manipulation Simple multiplexed functional readout
Disadvantages	Species differences Strain differences Lack of good disease models Ethics Integrate complexity of whole organism complicates interpretation Costs	Only short-term experiments High degree of experimental artefact Species and strain differences Difficult genetic manipulation	Unclear validity for human biology High degree of experimental artefact Limited maturity Limited experiences Methods to determine function undefined