Greetings,

Yes you can pursue your MBBS degree after BSC Cardiology, but you have to pursue your MSC degree and then MD in Cardiology. You have to appear for examinations like NEET and MCAT to gain admission in a medical school and fulfill allthe necessary requirements for medical licensing . After this you'll be allowed to practice medicine and obtain a doctoral degree.

For further information about NEET colleges, you can go through the link attached below.