Since your undergraduate degree was Bachelors in Science and not MBBS, you can not pursue an MD as your post graduate course. MD and MS are PG courses for UG graduates from the field of medicine. As a cardiovascular technologist, you can assist physicians and surgeons to treat problems related to CVS. If you want to study further, you have the following options-

1. Masters in Science (MSc)- This PG program is a 2 year program, eligibility for which is a BSc degree from a recognized university. Your degree may be named MSc CCIT ( Cardiac Catheterization & Interventional Technology) and MSc Cardiac.

2. Post Graduate Diploma program- PG Diploma in Cardiac Care Technology (PG-DCCT), and the PG Diploma in Cardiovascular Sonography

Requirements for Masters-

1. Pass in BSc (Cardiac Care / Cardiovascular Technology) or 2 years of Diploma in Cardiovascular Technology (post regular general BSc) with minimum 3 years of clinical experience.

2. 50 % or more aggregate marks in BSc or equivalent.

3. Completion of Clinical Experience/Internship.

4. Admission is done on the basis of the marks obtained in the Department Test (DT) & Personal Interview (PI).