Clinical and pathology.
1, triatrial heart is a rare congenital cardiovascular malformation, which refers to the presence of abnormal septum-like structures in the atria dividing the atria into two chambers, and can be divided into left atrial triatrial heart and right atrial triatrial heart. The clinical term “triple atrial heart” generally refers to the left atrial triple atrial heart.
The left atrium is divided by an abnormal fibromuscular septum into two parts: the posterior superior appendage (connected to the pulmonary vein) and the anterior inferior part of the innate atrium (connected to the mitral orifice). Because the septum constitutes a resistance to left atrial blood flow, the appendage is significantly enlarged and left ventricular blood flow is relatively low, resulting in hemodynamic changes similar to those seen in mitral stenosis; this malformation may exist alone or in combination with other malformations, most commonly atrial septal defect or complete pulmonary venous ectopic drainage.
Anatomy and typing of cases
1, paratrial and true atrial connections (typical triatrial heart): can be divided into.
A, without other connections.
B, with other abnormal connections and direct communication with the right atrium (i.e., combined atrial defect).
C, with anomalous connections and ectopic drainage of the whole pulmonary vein.
2.Para-atrial is not connected to the true atrium.
A, direct connection to the right atrium (i.e., combined atrial defect)
B, ectopic drainage of the whole pulmonary vein.
3, Incomplete triatrial heart: A
A, part of the pulmonary veins are connected to the true atrium through the paratrial, and the rest of the pulmonary veins are connected to the true atrium.
B, partial pulmonary vein connected to the true atrium via the paratrial and the remaining pulmonary veins are ectopically drained.
C, Some of the pulmonary veins connect to the right atrium via the collateral atrium, and the rest of the pulmonary veins enter the true atrium normally.
Clinical and pathology.
1, triatrial heart is a rare congenital cardiovascular malformation, which refers to the presence of abnormal septum-like structures in the atria dividing the atria into two chambers, and can be divided into left atrial triatrial heart and right atrial triatrial heart. The clinical term “triple atrial heart” generally refers to the left atrial triple atrial heart.
The left atrium is divided by an abnormal fibromuscular septum into two parts: the posterior superior appendage (connected to the pulmonary vein) and the anterior inferior part of the innate atrium (connected to the mitral orifice). Because the septum constitutes a resistance to left atrial blood flow, the appendage is significantly enlarged and left ventricular blood flow is relatively low, resulting in hemodynamic changes similar to those seen in mitral stenosis; this malformation may exist alone or in combination with other malformations, most commonly atrial septal defect or complete pulmonary venous ectopic drainage.
Anatomy and typing of cases
1, paratrial and true atrial connections (typical triatrial heart): can be divided into.
A, without other connections.
B, with other abnormal connections and direct communication with the right atrium (i.e., combined atrial defect).
C, with anomalous connections and ectopic drainage of the whole pulmonary vein.
2.Para-atrial is not connected to the true atrium.
A, direct connection to the right atrium (i.e., combined atrial defect)
B, ectopic drainage of the whole pulmonary vein.
3, Incomplete triatrial heart: A
A, part of the pulmonary veins are connected to the true atrium through the paratrial, and the rest of the pulmonary veins are connected to the true atrium.
B, partial pulmonary vein connected to the true atrium via the paratrial and the remaining pulmonary veins are ectopically drained.
C, Some of the pulmonary veins connect to the right atrium via the paratrial, and the rest of the pulmonary veins enter the true atrium normally.
Hemodynamic changes
In typical triple atrial heart, there is a septum between the paratrial and true atria, with only one or several small holes connected, and pulmonary vein stasis and high pressure are the inevitable result. If the parasternal atrium is not connected to the true atrium but is connected to the right atrium, the hemodynamic changes are similar to ectopic drainage of the whole pulmonary vein. In the case of incomplete triatrial heart, the obstruction of pulmonary venous return occurs only in the part of the lung lobe where the pulmonary veins are abnormally connected, while the rest of the lung lobe is open to venous drainage and pulmonary artery pressure may not be elevated.
Ultrasound diagnostic points and differential diagnosis
I. Echocardiographic sonographic manifestations are.
1. The left atrium is divided into two parts by abnormal septum-like echoes.
The pulmonary vein flows wholly or partially into the parasternal atrium, and the intrinsic atrium is connected to the mitral valve. The pulmonary venous blood can enter the left ventricle through the small hole in the septum, but the blood flow is blocked and causes functional mitral stenosis.
3.The left atrium is enlarged, and the right atrium can also be enlarged.
In partial triatrial heart, the opening of the pulmonary vein can be seen in the intrinsic left atrium.
5.In combination with other malformations, corresponding echocardiographic changes can be shown.
6.Color Doppler can show the high velocity blood flow through the septal foramen and the shunt blood flow of ASD or oval foramen in the intrinsic atrium.
7.Spectral Doppler can detect high-speed blood flow in the stenotic region of the atrium and shunt blood flow through the ASD or oval foramen without closure.
II. Right atrial triple atrium
One end of the right atrial triatrial septum mostly starts from the inferior vena cava, and the other end can be located at different levels on the right atrial side of the atrial septum, mostly in the lower part of the septum, immediately adjacent to the tricuspid annulus, separating the right atrium into two chambers, the anterolateral and the posterior medial. If the right atrial septum is semi-annular and does not affect the hemodynamic status of the patient, it usually cannot be called the right triatrial heart and can be called the right atrial septum.
C. Differential diagnosis.
A, Complete pulmonary vein ectopic drainage.
B, Perpetual left superior vena cava.
C, supra-micronomic stenosis.
Examination Difficulties and Precautions
The diagnosis of a typical triple atrial heart is not difficult. Two-dimensional ultrasound of the septal foramen in the left atrium is sometimes difficult to display. After displaying the septum, the probe should be swung back and forth, and color flow imaging and spectral Doppler should be used to help display the septal foramen. Because of the complexity and variety of triatrial heart types, the pulmonary vein connections should be traced in multiple views and attention should be paid to the presence of combined atrial defects!