Heart failure is the inability of the heart to pump oxygenated blood to the rest of the organs.
A cardiologist is a doctor who specializes in the diagnosis and treatment of diseases of the heart and blood vessels: the cardiovascular system.
The internist is the specialist in comprehensive care focused on diseases that affect internal organs and systems.
A surgeon is a doctor who can prevent and diagnose a disease through surgery.
Remember that for the proper selection of health professional that treats heart failure you must consider the nature, severity and symptoms you are presenting.