[6] After a brief stint as a faculty member at the PGIMER Chandigarh, he underwent further training in cardiac surgery at the Johns Hopkins, George Washington, and Georgetown University Hospitals and became a Fellow of the Royal College of Physicians and Surgeons of Canada in 1970.

[7] Valiathan served on the faculty of the Georgetown University Hospital,[8] PGIMER,[9] IIT Madras[8] and as director of SCTIMST.

In the first model, the major and minor struts were electron-beam welded and the valve was expected to withstand 360 million cycles of disc movement.

The third model had a housing made of a highly wear-resistant superalloy, "Haynes-25", a cobalt-based alloy of chromium, nickel and tungsten.

[11][12] However the fourth model was a success and more than 100,000 valves have been implanted in patients (until 2016).The multidisciplinary team at the Sree Chitra Institute led by Valiathan also developed a vascular graft and a series of disposable devices such as blood bags, oxygenators and cardiotomy reservoirs, which are in commercial production in industrial units in Kerala and Tamil Nadu.

[16] Later on, as a National Research Professor, he carried out a study of Sushruta and Vagbhata and completed the series of Legacy volumes on the 'Great Three' of Ayurveda'.

[17][18] In an interview, Valiathan had observed, "At this time there is no common ground where physicists, chemists, immunologists and molecular biologists can interact with Ayurvedic physicians.

[21] ASIIA made good progress and has been taken over by the Department of Science and Technology, Government of India, for sustained support under a "Task Force in Ayurvedic Biology", which appears on the SERB website.

[22] These lectures provided the material for his book Ayurvedic Inheritance; A Reader's Companion published by Manipal University Press in 2017.

Valiathan's contributions to medical sciences and technology brought him many honours and awards such as the Fellowships of the IAS, INSA New Delhi, NAS India, NAMS, INAE, The World Academy of Sciences, American College of Cardiology, the Royal College of Physicians of London and the International Union of Societies of Biomaterials and Engineering.

[26][27] He received the Dr. Samuel P. Asper International Award from the Johns Hopkins University[3] for his contributions to medical education.

[28] Valiathan served on numerous Government committees and academic councils which pertain to education, medicine, science and technology.