His work on the fluid dynamics of blood flow has had a major impact on the diagnosis and treatment of cardiovascular diseases such as atherosclerosis.

His elder brother Robert Chien (錢純) was former Minister of Finance of Taiwan, and former Secretary-general of Executive Yuan.

Chien is current President (since 1991) of the Whitaker Institute of Biomedical Engineering at the University of California, San Diego (UCSD).

He was named as a recipient of the National Medal of Science by President Barack Obama on September 27, 2011, for "pioneering work in cardiovascular physiology and bioengineering".

In other words, a healthy normal red blood cell is able to "squeeze" by deforming its shape and pass through small pores.

Chien and his colleagues discovered that this was a crucial factor in modulating viscosity and regulating blood flow and elucidated the mechanical, electrical and biochemical basis of this process.

These discoveries show that the shape of red blood cells is not accidental, but rather a highly "engineered design" meant for efficient transportation.