Cardiologists are doctors who specialize in the diagnosis, prevention and treatment of conditions related to the heart and blood vessels. A patient may be referred to a cardiologist if he experiences symptoms like chest pains, shortness of breath, dizziness, or high blood pressure. The physician will then evaluate your symptoms, take your health and family history and your weight. The cardiologist may order additional diagnostic tests, such as an echocardiogram, X-ray or blood tests. If necessary, the cardiologist may also call for a cardiac catheterization - a procedure in which a small tube is inserted into or near the heart that can take pictures of the heart's activity, or relieve blockage. Once determining whether there is a heart condition, a cardiologist will treat a patient through cholesterol management, cardiac rehabilitation, and fitness. If surgical intervention is required, like open-heart surgery, a cardiologist will make that determination, but a cardiothoracic surgeon will perform the procedure.

An internist is a physician who focuses on the diagnosis and treatment of conditions that affect the adult population—both acute and chronic.These doctors are often who adults see as their primary physicians because they treat a broad range of illnesses that do not require surgical or specialist interventions. They also work to help a patient maintain optimal health in order to prevent the onset of disease.In addition to treating the common cold and flu, internists also treat chronic diseases like diabetes and heart disease.

An ophthalmologist has the training to do much more than just prescribe glasses. They are physicians specially trained to diagnose and treat disorders of the eyes and vision. These doctors are experts on the complicated anatomy of the eye and are trained to treat eye diseases through both medical and surgical methods.Some common conditions that ophthalmologists treat are cataracts, glaucoma, strabismus, diabetic retinopathy, macular degeneration and amblyopia. In addition, ophthalmologists can provide prescriptions for eye glasses and contact lenses and perform LASIK surgery and other corrective surgeries for refractive errors like myopia (near-sightedness), hyperopia (far-sightedness), astigmatism and presbyopia.