Dr. Punitha Arasaratnam received her medical degree from the Royal College of Surgeons in Ireland (Dublin) in 2001. She graduated with honours and was awarded first prizes in physiology and pathology. She completed her internal medicine training mainly at the Kuala Lumpur General Hospital in Malaysia. She obtained membership to the Royal Colleges of Physicians based in the UK in 2008. She later pursued her cardiology training in Tan Tock Seng Hospital, in Singapore, and she completed her training in 2013.

Dr. Arasaratnam pursued a clinical and research fellowship in nuclear/PET/CT at the University of Ottawa Heart Institute in 2014, and another in cardiac MRI at the Stephenson Cardiac Imaging Centre at the University of Calgary the following year. Upon her return to Singapore, she served as a staff cardiologist under the National University Health System before moving on to private practice in 2021. She spearheaded the nuclear cardiology service and was actively involved in echocardiography and magnetic resonance imaging, including teaching undergraduates and residents. She was awarded the Public Healthcare Clinician Special Recognition Award for her commitment to patient care.

She completed a Master of Science degree in health economics, outcomes and management in cardiovascular sciences with merit from the London School of Economics and Political Science, and a diploma in organizational leadership from the University of Oxford, in England. She graduated with distinction in legal aspects of medical practice from Cardiff University, and she holds a Master's degree in business administration.

Dr. Arasaratnam provides clinical care in both the inpatient and outpatient settings, and directs the Anticoagulation Clinic. She also reports cardiac nuclear and magnetic resonance imaging studies.