The problems or diseases of the human heart and blood vessels are collectively called Cardiovascular diseases. Structural disorders of the heart are called Coronary heart diseases. Ischemic heart diseases are the conditions caused by the origin of heartbeat or irregularity of circulation. Chest pain is felt when the lumen of the coronary artery is narrowed by 50-70% by fatty deposits, and chest pain occurs when it is narrowed by 90-99%. Heart disease is the number one killer disease in the developed world. Because 30% of the total deaths in the world are caused by heart disease. The prevalence of this disease is high between 15-30 years of working life. Notable heart diseases are hypertension, hypotension, coronary heart disease, cardiomegaly (enlarged heart), valvular heart disease (valvular dysfunction), congenital heart disease (born), pericarditis (inflammation of the pericardium), cardiomyopathy (heart muscle disease), rheumatic disease (heart muscle and valves) etc.