A cardiologist is a doctor who specializes in treating the heart and associated cardiovascular system. Cardiologists perform a wide range of tasks on a daily basis, from using medical imaging studies to diagnose a heart condition to working with a cardiac surgeon to establish a treatment plan for a patient. This medical specialty also has several subspecialties, for doctors who want to focus on a specific aspect of medical care for the heart.

Typically, in order to become a cardiologist, a doctor must complete medical school and a residency in internal medicine before applying for a fellowship in cardiology. A cardiology fellowship generally lasts around three years, and it includes training in using diagnostic tools, talking with patients, networking with other doctors, and using things like pacemakers and medication to treat heart conditions. Once the fellowship is completed, the doctor can apply for certification as a cardiologist before beginning to practice, or he or she can pursue training in a subspecialty.

Typically, a cardiologist sees patients because they are referred by other doctors who have concerns about their heart health. When a cardiologist meets a new patient, the patient is interviewed and the doctor may run some diagnostic tests to get more information about the patient's condition. When the doctor reaches a diagnosis, he or she can discuss the patient's condition and treatment options.

Cardiologists can use tools like stress testing, cardiac catheterization, radiology studies, and a variety of other techniques to diagnose heart conditions. Various treatments including medication and lifestyle changes can be used to treat diagnosed conditions. If a cardiologist decides that a condition needs to be treated surgically, he or she will bring a cardiothoracic surgeon onto the patient's team to discuss surgical options. Typically, after a surgery is completed, a cardiologist performs follow-up care to ensure that the surgery went well and that the patient stays as healthy as possible.

If a cardiologist chooses to do so, he or she can specialize in things like interventional cardiology, nuclear cardiology, electrophysiology, or echocardiography. These advanced techniques in the field of cardiology can be used to provide additional diagnostic studies for a patient with a heart condition, and to treat heart conditions with innovative technology.

In the course of a day's work, a cardiologist will interact with a wide range of patients, from young adults with congenital heart defects to geriatric patients with cardiovascular disease. Heart disease is a leading killer in many developed countries, so a cardiologist always has plenty of work to do.