Cardiology is the branch of medicine that focuses on the study, diagnosis, and treatment of disorders of the heart and circulatory system. Cardiologists are medical doctors who specialize in the prevention, diagnosis, and treatment of heart-related diseases such as heart attacks, high blood pressure, heart failure, and arrhythmias. They use a variety of medical tests and procedures, such as echocardiograms, stress tests, and cardiac catheterizations, to evaluate and monitor patients with heart conditions. Cardiology is a critical field of medicine as heart disease remains one of the leading causes of death worldwide.