A cardiologist is a medical doctor specializing in diagnosing, treating, and preventing heart and blood vessel diseases. Their work includes performing tests like electrocardiograms (ECGs), echocardiograms, and stress tests to assess heart health. They treat conditions such as coronary artery disease, heart attacks, arrhythmias, and heart failure. Treatments can involve lifestyle changes, medications, or procedures like angioplasty, stent placement, and pacemaker insertion. Cardiologists also provide post-treatment care and work with patients to manage chronic heart conditions. Their goal is to improve heart health and prevent cardiovascular diseases through both medical and interventional therapies.