Dr. Krishna Iyer is one of India's front ranking paediatric cardiac surgeons, recognised for his clinical expertise and wide ranging involvement with cardiac care for children in India and other developing nations, Dr. Iyer initiated the first dedicated paediatric cardiac care program in Northern India , a pioneering initiative, at Escorts Heart Institute Research Centre( now Fortis-Escorts Heart Institute ) in 1995. Under his guidance this paediatric cardiac program has become the benchmark for cardiac care for children for India and its South East Asian neighbours. Dr. Iyer has operated on more than 10,000 babies, children and adults with congenital heart diseases comprising various procedures like arterial switch procedure, double switch operation TAPVC repairs, Fontan and Fontan type procedures, corrections for tetralogy of Fallot, DORV, Truncus etc. Senning operation, conduit repairs and wide range of one stage and multi-stage corrections for complex congenital heart diseases. He has done original work on rapid two-stage arterial switch procedure and performed the first successful rapid two stage arterial switch and double-switch operation in India. His current interests are perfecting complex neonatal cardiac surgery, cardiac surgery in malnourished infants and children, salvaging late presenters of congenital heart disease, and developing cost effective cardiac care for children in developing countries. After basic training, he joined the Department of Cardiothoracic and Vascular Surgery at AIIMS and was Additional Professor at the time he moved to Escorts Heart Institute to set up its paediatric cardiac care division. He trained in paediatric and infant cardiac surgery under the guidance of the renowned paediatric cardiac surgeon Dr. R.B.B.Mee as Senior Fellow at the Department of Paediatric Cardiac Surgery at Royal Children's Hospital, Melbourne in Australia in 1989. He is involved in many charities for underprivileged children, most notably the 'Gift of Life' program of Rotary International.

During his academic career Dr. Iyer has won many awards. Some of these are the Institute Gold Medal for Best Graduate of the year at MBBS examination, Sorel Catherine Friemna Prize for proficiency in Paediatrics, Pfizer Postgraduate Medical Award, Gold Medal and Scroll of Honour, Hira Lal Gold Medal for being the best postgraduate in General Surgery. He was awarded the Doppler award for best paper at the Sixth International Symposium on Echocardiography in Cardiac Surgery held in Washington D.C. in 1994. He has been designated Paul Harris Fellow of the Rotary International Foundation for humanitarian services for children.