To become a cardiologist or Neurologists you must have to appear for the competitive entrance exam for MBBS (Bachelor of Medicine and Bachelor of Surgery).
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Becoming a cardiologist generally entails several years of training beyond an MBBS degree, as well as licensure and board certification. To become a cardiologist after taking MD / MS / DNB, one has to go for a DM in Cardiology. For more about cardiologist click here