Sim plays an active role in various research projects and clinical trials and is the National Leader for Singapore for a few key global pharmacological heart failure trials. His clinical interest is in Heart Failure.

Research Interests:
Epidemiology of heart failure in Asia (Director of Heart Failure in charge of setting up the Heart Failure programme in National Heart Centre Singapore)
Pharmacological therapy for acute and chronic heart failure for reduced and preserved ejection fraction (Director of Heart Failure, National Heart Centre Singapore)
National Leader for Singapore for key global trials on pharmacological therapy for heart failure
Mechanical assist devices in advanced heart failure (Principal cardiologist involved in the mechanical assist device programme in National Heart Centre Singapore)
Advance care planning and end of life issue in heart failure (Director of the Advance Care Planning (ACP) programme in National Heart Centre and member of the ACP National steering committee)