If the heart is compared to a “house”, it has five main functional areas – waterways, electrical circuits, walls, doors and windows, and external decoration, which are briefly described below. 1.Heart waterway problem: The waterway of the heart is the blood vessels, including the arterial and venous systems. Such as the aorta, pulmonary artery, pulmonary vein, superior vena cava, inferior vena cava, coronary artery and so on. A lesion in any of them is called a vascular lesion. An example is aortic coarctation. And the often said myocardial infarction is caused by the narrowing and occlusion of coronary arteries. 2, heart circuit disease: is a variety of arrhythmias. A normal heartbeat requires electrical signals from the sinus node to be initiated and transmitted down through the atrioventricular bundle, junctional area, Hitchcock’s bundle, and Purkinje fibers in sequence before the sequential contraction and beating of the heart occurs and then blood can be pumped outward. If there is a problem in any of the above circuits, it will cause the heart to beat irregularly, leading to arrhythmia diseases such as premature beats and arrests. 3, the walls of the heart: the “compartments” between the atria and ventricles, called the atrial septum, the septum and the heart muscle (the outer walls of the house). If the walls become thin, thick or have holes, it is often referred to as cardiomyopathy, myocardial perforation, atrial and ventricular septal defects and other diseases. 4, heart door and window disease: is the heart’s valve disease, such as the door between the left atrium and ventricle is called mitral valve, the door between the right atrium and ventricle is called tricuspid valve, etc.. These doors are regularly open and closed. If there is valve aging, defect, tear, infection, etc., it will cause valve stenosis or incomplete closure and other diseases. 5, the external decoration of the heart disease: the outside of the heart has a membrane, called the pericardium, wrapped around the heart, which has a small amount of plasma, to lubricate the heart. If inflammation occurs in the pericardium, it can all affect the contraction of the heart and cause pericardial diseases such as pericarditis. In addition, various diseases can co-exist or occur sequentially.