Cardiologists are medical professionals that examine and treat illnesses associated with the cardiovascular system which includes the heart and blood vessels. They also help their patients learn about their risk factors for heart disease and determine what treatment or procedure should they undergo. A pediatric cardiologist is a specialized physician within cardiology who treats and diagnoses heart complication in children. Cardiologists who specialize in cardiac catheterization, angioplasty, and stenting treatment and diagnosis are usually called Interventional cardiologists.