Health Minister Ma Subramanian underwent a coronary angiogram in Omandurar Government Multi Super Speciality Hospital in Chennai on Wednesday. The minister complained of dizziness while meeting visitors at his residence after his morning walk.He was taken to the Kalaignar Centenary Multispeciality Hospital in Guindy where he underwent some tests. Doctors, who noticed mild changes in the ECG, referred him to Tamil Nadu Government Multi Super Speciality Hospital (Omandurar hospital) for a coronary angiogram.