Common arterial trunk

A common arterial trunk is formed if during prenatal development a primitive trunk is not divided by a septum into the pulmonary artery and aorta, which leads to the formation of a single large arterial trunk that is located above the large, peremembranous infundibular defect of the interventricular septum. Accordingly, mixed blood enters the systemic circulation, into the lungs and brain. Symptoms of a common arterial trunk include cyanosis, eating disorders, sweating and tachypnea. Often a normal I tone and a loud single tone II are heard; noise can be different. Diagnosis is based on echocardiography or cardiac catheterization. After medical treatment of heart failure, as a rule, surgical correction follows. It is recommended to prevent endocarditis.

The total arterial trunk is 1-2% among congenital heart defects. Approximately 35% of patients have DiGeorge syndrome or palate-cardio-facial syndrome. There are 4 types. At type I the pulmonary artery departs from the trunk, then it divides into the right and left pulmonary arteries. In types II and III, the right and left pulmonary arteries depart independently from the posterior and lateral sections of the trunk, respectively. With type IV, the arteries that drain from the descending aorta supply blood to the lungs; This type is today considered to be a severe form of the tetralogy of Fallot.

Other anomalies may also be present (eg, barrel valve failure, coronary artery anomalies, autrioventricular communication, double aortic arch), which may increase postoperative lethality.

Physiological consequences of type I include mild cyanosis, heart failure (CH), and marked increase in blood flow in the lungs. In types II and III, cyanosis is more noticeable, and heart failure is rare, since pulmonary blood flow is normal or only slightly intensified.

[1], [2], [3], [4], [5], [6]

Symptoms of a common arterial trunk

Newborns with type I manifestations include mild cyanosis and symptoms and manifestations of heart failure (tachypnea, malnutrition, sweating) that appear in the first weeks of life. In newborns with type II and type III there is more pronounced cyanosis, however, heart failure develops less often.

With a physical examination, you can detect an increased heart beat, an increase in pulse pressure, a loud and single II tone and a click of exile. A holosystolic murmur of intensity 2-4 / 6 is heard at the left edge of the sternum. Noise on the mitral valve in the middle of the diastole can be heard at the apex with an increase in blood flow in the small circle of the circulation. When the valve of the arterial trunk is inadequate, the high-tone diastolic noise decreasing is heard in the third intercostal space to the left of the sternum.

Diagnosis of the common arterial trunk

The diagnosis is made on the basis of clinical data, taking into account the chest radiograph and ECG, an accurate diagnosis is established based on two-dimensional echocardiography with color Dopplercardiography. Cardiac catheterization is often necessary to clarify the attendant anomalies before surgery.

Radiography of the chest shows cardiomegaly of varying severity with augmentation of the pulmonary pattern, right aortic arch (about 30%) and a relatively high location of the pulmonary arteries. The ECG often reveals hypertrophy of both ventricles. Significant increase in pulmonary blood flow can cause the appearance of signs and hypertrophy of the left atrium.

[7], [8], [9], [10]

Treatment of a common arterial trunk

In heart failure, an active medication is prescribed, including diuretics, digoxin and ACE inhibitors, and then the operation is performed early. Intravenous prostaglandin infusion does not have significant advantages.

Surgical treatment of the common arterial trunk consists of a complete primary correction of the defect. The defect of the interventricular septum is closed, so that blood enters the arterial trunk from the left ventricle. Between the right ventricle and the site of the divergence of the pulmonary arteries, a channel is placed with or without a valve. Surgical lethality is 10-30%.

All patients who have a common arterial trunk should receive endocarditis prophylaxis before dental or surgical procedures in which bacteraemia may develop.