The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide to the lungs. In humans, the heart is approximately the size of a closed fist and is located between the lungs, in the middle compartment of the chest, called the mediastinum.
Coronary circulation is the circulation of blood in the arteries and veins that supply the heart muscle (myocardium). Coronary arteries supply oxygenated blood to the heart muscle. Cardiac veins then drain away the blood after it has been deoxygenated. Because the rest of the body, and most especially the brain, needs a steady supply of oxygenated blood that is free of all but the slightest interruptions, the heart is required to function continuously. Therefore its circulation is of major importance not only to its own tissues but to the entire body and even the level of consciousness of the brain from moment to moment. Interruptions of coronary circulation quickly cause heart attacks, in which the heart muscle is damaged by oxygen starvation. Such interruptions are usually caused by coronary ischemia linked to coronary artery disease, and sometimes to embolism from other causes like obstruction in blood flow through vessels.
The papillary muscles are muscles located in the ventricles of the heart. They attach to the cusps of the atrioventricular valves via the chordae tendineae and contract to prevent inversion or prolapse of these valves on systole.
A pulmonary artery is an artery in the pulmonary circulation that carries deoxygenated blood from the right side of the heart to the lungs. The largest pulmonary artery is the main pulmonary artery or pulmonary trunk from the heart, and the smallest ones are the arterioles, which lead to the capillaries that surround the pulmonary alveoli.
The coronary arteries are the arterial blood vessels of coronary circulation, which transport oxygenated blood to the heart muscle. The heart requires a continuous supply of oxygen to function and survive, much like any other tissue or organ of the body.
The atrioventricular node or AV node electrically connects the heart's atria and ventricles to coordinate beating in the top of the heart; it is part of the electrical conduction system of the heart. The AV node lies at the lower back section of the interatrial septum near the opening of the coronary sinus, and conducts the normal electrical impulse from the atria to the ventricles. The AV node is quite compact.
The cardiac conduction system transmits the signals generated by the sinoatrial node – the heart's pacemaker, to cause the heart muscle to contract, and pump blood through the body's circulatory system. The pacemaking signal travels through the right atrium to the atrioventricular node, along the bundle of His, and through the bundle branches to Purkinje fibers in the walls of the ventricles. The Purkinje fibers transmit the signals more rapidly to stimulate contraction of the ventricles.
AV-nodal reentrant tachycardia (AVNRT) is a type of abnormal fast heart rhythm. It is a type of supraventricular tachycardia (SVT), meaning that it originates from a location within the heart above the bundle of His. AV nodal reentrant tachycardia is the most common regular supraventricular tachycardia. It is more common in women than men. The main symptom is palpitations. Treatment may be with specific physical maneuvers, medications, or, rarely, synchronized cardioversion. Frequent attacks may require radiofrequency ablation, in which the abnormally conducting tissue in the heart is destroyed.
The atrium is one of the two upper chambers in the heart that receives blood from the circulatory system. The blood in the atria is pumped into the heart ventricles through the atrioventricular mitral and tricuspid heart valves.
In the blood supply of the heart, the right coronary artery (RCA) is an artery originating above the right cusp of the aortic valve, at the right aortic sinus in the heart. It travels down the right coronary sulcus, towards the crux of the heart. It gives off many branches, including the sinoatrial nodal artery, right marginal artery, posterior interventricular artery, conus artery, and atrioventricular nodal branch. It contributes the right side of the heart, and parts of the interventricular septum.
In cardiology, the cardiac skeleton, also known as the fibrous skeleton of the heart, is a high-density homogeneous structure of connective tissue that forms and anchors the valves of the heart, and influences the forces exerted by and through them. The cardiac skeleton separates and partitions the atria from the ventricles .The heart's cardiac skeleton comprises four dense connective tissue rings that encircle the mitral and tricuspid atrioventricular (AV) canals and extend to the origins of the pulmonary trunk and aorta. This provides crucial support and structure to the heart while also serving to electrically isolate the atria from the ventricles.
The coronary sinus is the largest vein of the heart. It drains over half of the deoxygenated blood from the heart muscle into the right atrium. It begins on the backside of the heart, in between the left atrium, and left ventricle; it begins at the junction of the great cardiac vein, and oblique vein of the left atrium. It receives multiple tributaries. It passes across the backside of the heart along a groove between left atrium and left ventricle, then drains into the right atrium at the orifice of the coronary sinus.
The coronary sulcus is a groove on the surface of the heart at the base of right auricle that separates the atria from the ventricles. The structure contains the trunks of the nutrient vessels of the heart, and is deficient in front, where it is crossed by the root of the pulmonary trunk. On the posterior surface of the heart, the coronary sulcus contains the coronary sinus. The right coronary artery, circumflex branch of left coronary artery, and small cardiac vein all travel along parts of the coronary sulcus.
The circumflex branch of left coronary artery is a branch of the left coronary artery. It winds around the left side of the heart along the atrioventricular groove. It supplies the posterolateral portion of the left ventricle.
The right marginal branch of right coronary artery is the largest marginal branch of the right coronary artery. It follows the acute margin of the heart. It supplies blood to both surfaces of the right ventricle.
Coronary artery anomalies are variations of the coronary circulation, affecting <1% of the general population. Symptoms include chest pain, shortness of breath and syncope, although cardiac arrest may be the first clinical presentation. Several varieties are identified, with a different potential to cause sudden cardiac death.
The left anterior descending artery is a branch of the left coronary artery. It supplies the anterior portion of the left ventricle. It provides about half of the arterial supply to the left ventricle and is thus considered the most important vessel supplying the left ventricle. Blockage of this artery is often called the widow-maker infarction due to a high risk of death.
The sinoatrial nodal artery, sinuatrial nodal artery or sinoatrial artery is an artery of the heart which supplies the sinoatrial node, the natural pacemaker center of the heart. It is usually a branch of the right coronary artery. It passes between the right atrium, and the opening of the superior vena cava.
The crux cordis or crux of the heart is the area on the lower back side of the heart where the coronary sulcus and the posterior interventricular sulcus meet. It is important surgically because the atrioventricular nodal artery, a small but vital vessel, passes in proximity to the crux of the heart. It is the anastomotic point of right and left coronary artery.
The heart is a muscular organ situated in the mediastinum. It consists of four chambers, four valves, two main arteries, and the conduction system. The left and right sides of the heart have different functions: the right side receives de-oxygenated blood through the superior and inferior venae cavae and pumps blood to the lungs through the pulmonary artery, and the left side receives saturated blood from the lungs.
