Dissectr. Sample Questions

Right Coronary Artery

The right coronary artery (RCA) originates above the right cusp of the aortic valve. It travels down the right atrioventricular groove, towards the crux of the heart. It branches into the posterior descending artery and the right marginal artery. At the origin of the RCA is the conus artery.

In addition to supplying blood to the right ventricle (RV), the RCA supplies 25% to 35% of the left ventricle (LV).

In 85% of patients (Right Dominant), the RCA gives off the posterior descending artery (PDA).

Ascending Aorta

Commences at the upper part of the base of the left ventricle, on a level with the lower border of the third costal cartilage behind the left half of the sternum. It’s total length is about 5 centimetres (2.0 in).

The only branches of the ascending aorta are the two coronary arteries which supply the heart; they arise near the commencement of the aorta from the aortic sinuses which are opposite the aortic valve.

Mitral Valve

The mitral valve lies between the left atrium (LA) and the left ventricle (LV). The mitral valve is typically 4–6 cm² in area and has two cusps.

Tricuspid Valve

The tricuspid valve lies between the right atrium and the right ventricle. The function of the valve is to prevent back flow of blood into the right atrium. The normal tricuspid valve usually has three cusps.

Pulmonary Valve

The pulmonary valve is a semilunar valve that lies between the right ventricle and the pulmonary artery and has three cusps. Similar to the aortic valve, the pulmonary valve opens during ventricular systole.

Left Coronary Artery

The left coronary artery is an artery that arises from the aorta above the left cusp of the aortic valve and supplies blood to the left side of the heart.

It typically runs for 10 to 25 mm and then bifurcates into the left anterior descending (LAD) and the left circumflex artery.

Anterior Interventricular Branch of the Left Coronary Artery (Left Anterior Descending Artery)

The artery supplies the anterolateral myocardium, apex, and interventricular septum. The left anterior descending (LAD) typically supplies 45-55% of the left ventricle (LV) and is therefore considered the most critical vessel in terms of myocardial blood supply.

Circumflex Artery

The circumflex artery is a branch of the left coronary artery. The circumflex artery curves to the left around the heart within the coronary sulcus, giving rise to one or more left marginal arteries as it travels towards the posterior surface of the heart.

Left Coronary Sinus

The coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the heart muscle (myocardium). It delivers deoxygenated blood to the right atrium.

Right Coronary Sinus

The coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the heart muscle (myocardium). It delivers deoxygenated blood to the right atrium.

Cardiac Fibrous Skeleton

The cardiac skeleton, also known as the fibrous skeleton of the heart, is a high density single structure of connective tissue that forms and anchors the valves and influences the forces exerted through them. The cardiac skeleton separates and partitions the atria from the ventricles.

SA Nodal Artery

The sinoatrial nodal artery is an artery of the heart which supplies the sinoatrial node and arises from the right coronary artery in around 60% of people. In about 40% of cases, the sinoatrial artery is a branch of the left coronary artery or one of its branches.