Heart diseases refer to conditions that affect the structure and function of the heart, leading to poor circulation and reduced oxygen supply to the body. Common heart problems include palpitations, irregular heartbeat (arrhythmia), chest pain (angina), and heart attack (myocardial infarction). These conditions are often caused by stress, high blood pressure, cholesterol, diabetes, unhealthy lifestyle, or blocked arteries. If not treated in time, heart diseases can become serious, but with proper medical care, lifestyle management, and heart-strengthening therapies, heart function can be improved and future risk can be reduced.