Radiologist
Radiologists are medical specialists that specialize in employing medical imaging (radiology) methods (exams/tests) such as X-rays, computed tomography (CT), magnetic resonance imaging (MRI), nuclear medicine, positron emission tomography (PET), and ultrasound to diagnose and treat injuries and diseases.
Cardiologist
A cardiologist is a medical specialist that specializes in the study and treatment of diseases and conditions of the cardiovascular system, which includes heart rhythm abnormalities, coronary artery disease, heart attacks, heart defects and infections, and related disorders. A cardiologist's education is extensive, requiring more than ten years of medical school.