What Is the Right Atrium?

The right atrium is one of the four cavities of the heart and is the rightmost part of the heart cavity. The right atrium is divided into anterior and posterior parts. The anterior part is called the intrinsic right atrium. The posterior part is the vena cava sinus. The anterior upper part of the intrinsic atrium has an ear-like protrusion called the right atrial appendage. The inner wall surface of the intrinsic atrium is not smooth. When the heart function is impaired and blood flow is slow, thrombus is easily formed here. The right atrium has the right atrium vent, which opens into the right ventricle.

The right atrium is one of the four cavities of the heart and is the rightmost part of the heart cavity. The right atrium is divided into anterior and posterior parts. The anterior part is called the intrinsic right atrium. The posterior part is the vena cava sinus. The inner wall of the sinus is smooth. The anterior upper part of the intrinsic atrium has an ear-like protrusion called the right atrial appendage. The inner wall surface of the intrinsic atrium is not smooth. When the heart function is impaired and blood flow is slow, thrombus is easily formed here. The right atrium has the right atrium vent, which opens into the right ventricle.

Chinese name

Right atrium

Foreign name

right atrium, atrium dextrum

Function

The venous return of the heart itself

Structure

Three entrances and one exit

Right atrium anatomy:

1. Right atrium:

The right atrium is located above the right half of the coronary sulcus. The front wall protrudes to the right atrial appendage, and there are many parallel bulges on the inner surface, called comb muscles. The inner surface of the posterior wall is smooth, with the entrance of the superior vena cava at the upper back and the entrance of the inferior vena cava below. The left front of the inferior vena cava port is the right atrioventricular port with a coronary sinus entrance between the two ports. The inner wall of the right atrium is the right side of the atrial septum, and there is an oval shallow fossa at the lower part, called the oval fossa. It is a vestige left after the oval holes that left and right atriums were closed during embryonic period . If the hole is not closed or incompletely closed due to the cause, it will become one of the common congenital heart diseases.

Right atrium (5 photos)

2. Heart:

Muscular organs that promote blood circulation. It is located in the chest, between the left and right lungs, and surrounded by the pericardium. Inside there are two atria, the middle is the atrial septum, the two ventricles, the middle is the ventricular septum. The left atrioventricular mouth has a mitral valve and the right atrioventricular mouth has a tricuspid valve, which makes the blood flow unidirectionally. Due to the rhythmic contraction of the myocardium, the venous blood enters the right ventricle from the right atrium, becomes arterial blood after gas exchange through the lungs, enters the left atrium and then to the left ventricle, and is then transported to the arterial blood vessels in various parts of the body.

Morphological structure of right atrium:

One of the four chambers of the heart. It is the rightmost part of the heart cavity with a wall thickness of about 2mm. The right atrium is divided into anterior and posterior, the anterior is the intrinsic atrium, and the posterior is the vena cava sinus. These two parts are bounded by the shallow groove on the surface of the right edge, the boundary groove. The inner wall of the rear part is smooth, and there are upper vena cava and inferior vena cava ports on the upper and lower sides respectively. There is a longitudinal muscle bulge corresponding to the boundary groove between the two ports, which is called the boundary crest. The inferior vena cava valve has an inferior vena cava valve at the front edge, and its medial end extends to the leading edge of the oval fossa. During the fetal period, it guides the blood of the inferior vena cava to the left atrium through the oval hole. The coronary sinus ostium is located between the inferior vena cava and the right atrium ventricle, and there is a coronary sinus valve at the lower edge of the mouth. The anterior upper ear of the intrinsic atrium protrudes as the right atrial appendage, and the inner wall has a parallel muscle bulge from the frontal ridge, called the comb muscle. The comb-like muscles are staggered to the inner surface of the right atrial appendage, many of which are honeycomb-shaped. When heart dysfunction and blood stasis occur, thrombus is easily formed in the heart ear. The postero-medial wall of the right atrium is mainly composed of the atrial septum, and the lower part of it has a shallow depression, called the oval fossa. It is the remnant after the oval hole was closed during the fetal period, and most of the atrial septal defects occurred here.

Right atrium and right atrium-related diseases:

Myxoma:

Overview:

Myxoma is the most common primary tumor of the heart. The left atrium is three times more than the right atrium and can be bilateral. The main clinical manifestations of myxoma are atrioventricular valve obstruction, systemic reactions, and peripheral embolism. Myocardial tumors in the left atrium obstruct the atrioventricular valve much like mitral stenosis. Myxomas often originate from the atrial septum and often have a pedicle (handle). The tumor can move, so the symptoms and signs can change with the body position. When the position suddenly changes, syncope may be caused by the infarcted atrioventricular valve; periodic venous stasis in the lungs; occasional myxoma prevents the mitral valve from closing, causing mitral regurgitation. Myxoma of the right atrium can cause tricuspid orifice obstruction and chronic right heart failure.

symptom:

Systemic manifestations may be the body's abnormal immune response to myxoma, which can sometimes be the main symptom of the disease, including sore muscles and joints, low fever, anemia, accelerated red blood cell sedimentation, and abnormal serum proteins. Myxoma of the left atrium may have first hypercardia and rumbling diastolic or systolic murmur in the apical region, and sometimes "tumor flutter" in early and middle diastole (like the third heart sound or extra ventricular galloping rhythm) Sound), individual patients may only have apical systolic murmurs. On auscultation, it is often intermittent. When sitting, it can show low-key diastolic murmurs in the apical region and simultaneous dyspnea, cyanosis, and fainting (mitral valve obstruction); when the supine position is eliminated, the murmurs are often not heard and the symptoms are reduced .

diagnosis:

If the patient has no history of rheumatic fever and has intermittent, position-related dyspnea (dyspnea occurs in the sitting position, and shortness of breath resolves in the supine position), auscultation finds frequent changes, systemic embolism (appears in about 50% of cases), anemia , ESR and other phenomena, the possibility of atrial myxoma should be considered. Ultrasound can show cloud-like clumps in the atrium. Cardiovascular imaging showed intraatrial defects.

Surgical resection under extracorporeal circulation not only relieves mechanical obstruction, but also the immune changes are rapidly resolved.