RU2830638C1 - Method for ultrasonic diagnosis of abnormal position and branching of aortic arch in newborns and infants - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to medicine, namely to X-ray diagnostics, and can be used for ultrasonic evaluation of spatial anatomy of the aortic arch system. Ultrasonic examination of upper mediastinum is performed from parasternal approach with orientation of sensor marker at 3 o'clock. Further, continuous transverse scanning is performed in the cranial direction to obtain two successive sections passing through the trachea: at the level of the transverse aortic arch and the arterial duct, at the level of the origin of the brachiocephalic arteries (BA) directly from the aortic arch. When determining the aortic arch and the arterial duct on the left of the trachea, the left aortic arch and the left arterial duct are diagnosed, when determining the aortic arch and the arterial duct to the right of the trachea, the right aortic arch and the right arterial duct are diagnosed, when determining an aortic arch on both sides of a trachea, a double aortic arch is diagnosed. When determining three BA located along a straight line to the left of the trachea, wherein the first BA has the largest diameter, the aberrant passage of the right subclavian artery is excluded, if observing three BA with relatively equal diameter, located along a straight line at an equal distance from each other to the left or to the right of the trachea, an aberrant course of the subclavian artery is diagnosed; if the BA are mirror-symmetrical relative to the trachea, a double aortic arch is diagnosed.

EFFECT: method enables increasing the accuracy of assessing the spatial anatomy of the aortic arch and its branches by performing the echocardiographic examination of a combination of two successive transverse sections of the superior mediastinum.

1 cl, 3 ex

Description

The proposed method relates to the field of medicine, in particular to radiation diagnostics, and is intended for ultrasound assessment of the spatial anatomy of the aortic arch system, namely, determining the lateralization of the transverse aortic arch, the course and location of the arterial duct, and establishing the nature of the origin of the brachiocephalic arteries. The information obtained can be used for ultrasound diagnostics of anomalies in the position and branching of the aortic arch (vascular rings) in newborns and young children.

Congenital anomalies of the aortic arch and brachiocephalic arteries that form a vascular ring are represented by a wide range of anatomical variants and forms, which include a double aortic arch, abnormal location of the brachiocephalic arteries and arterial duct/ligament at the right and left aortic arch. Deviant position of the aortic arch and its branches, as well as abnormal course of the arterial duct disrupt the complex topography of the organs of the upper mediastinum and, in certain cases, lead to the formation of vascular rings around the trachea and esophagus with varying degrees of compression (Shatalov K.V. Vascular rings and vascular loops. In the book: Bokeria L.A., Shatalov K.V. Pediatric cardiac surgery: a manual for doctors. Moscow: A.N. Bakulev National Center for Cardiovascular Surgery; 2016: 747–57). Clinical manifestations of vascular rings are determined by the degree of compression of the central respiratory tract and/or esophagus, as well as the degree of damaging effect of a large pulsating vessel on their wall. In newborns and young children, the anomalies under discussion cause the child's death during an attack of apnea, asphyxia, or as a result of aspiration pneumonia (Grigoryants T.R., Kim A.I., Rogova T.V., Akatov D.S. Vascular rings: the current state of the problem. Children's diseases of the heart and blood vessels. 2022; 19 (4): 263–71).

The unexpected course of the mediastinal arteries may cause difficulties during cardiac, thoracic, or laryngeal surgery, as well as during catheterization of large vessels during other invasive procedures. The course and anatomy of the vessels must be accurately determined before any elective chest and neck surgery, even in the absence of symptoms indicating conflict between the airway and esophagus.

Computed tomography (CT) and magnetic resonance imaging (MRI) of the chest organs allow obtaining images of extracardiac structures of the heart (major vessels and their branches, arterial duct), central respiratory tract (trachea, main bronchi) in different planes, assessing their relationship with each other, as well as compression of the trachea and esophagus in one study. However, despite the high information content, both methods have a number of disadvantages and limitations regarding their use in the pediatric population. Ionizing radiation, which is inevitable when performing CT, and the long imaging time required for MRI, which leads to the need for sedation or even anesthesia with intubation, are major concerns, particularly when performing diagnostic procedures in the neonatal period and in patients with potentially compromised airways (with a vascular ring) (Schooler G., Cravero J.P., Callahan M.J. Assessing and conveying risks and benefits of imaging in neonates using ionizing radiation and sedation/anesthesia. Pediatr. Radiol. 2021; 52: 616–21; Brenner D., Elliston C., Hall E., Berdon W. Estimated risks of radiation-induced fatal cancer from pediatric CT. AJR Am. J. Roentgenol. 2001; 176 (2): 289–96). Therefore, these types of examination should not be used as routine diagnostic screening in childhood, especially in newborn patients. It is worth noting that CT and MRI are expensive studies.

In the pediatric population, ultrasound diagnostics (echocardiography) is the method of choice due to its general availability, the ability to provide information in real time, the absence of ionizing radiation and contraindications.

Echocardiography allows for a fairly accurate assessment of the two-dimensional anatomy (size and continuity of the arch) in obstructive anomalies of the aortic arch, such as coarctation and arch interruption, and the use of Doppler modes allows for an assessment of hemodynamics. However, the standard transthoracic echocardiography technique is limited to projections obtained in parasagittal planes that do not reflect the syntopy of the aortic arch and trachea. In this case, the extracardiac structures of the heart are hidden for most of their course by the bone structures of the chest and aerated lung tissue/airways, which screen the area of study and degrade the quality of the ultrasound image (Zakharova O.E., Plakhova V.V. Echocardiography for solving cardiac surgical problems in newborns and young children with anomalies of the aortic arch and brachiocephalic vessels. Thoracic and cardiovascular surgery. 2019; 61 (1): 14–20).

Transthoracic ultrasound imaging in neonates and young children differs from echocardiographic imaging in older patients. The anatomical and physiological characteristics of this period (thin structures of the anterior chest with less pronounced ossification and hypoechoic tissue of the thymus gland) determine the optimal transthoracic ultrasound imaging for echocardiographic examination of extracardiac structures of the heart (He X., Chen J., Li G. Study on the views and methods of ultrasonic screening and diagnosis for abnormal aortic arch in infants. Cardiovasc. Ultrasound. 2021; 19 (1): 8).

All of the above determines the relevance and prospects of developing a method for ultrasound assessment of the anatomy of the aortic arch and brachiocephalic arteries, which makes it possible to establish the complex spatial anatomy of congenital anomalies of the aortic arch and its branches (vascular rings) in newborns and young children.

To date, ultrasound semiotics of congenital anomalies of the aortic arch and brachiocephalic arteries (vascular rings) has not been developed; a comprehensive approach has not been proposed that could be applied not only to a specific anatomical variant of the defect, but also to various anomalies of the position and branching of the aortic arch. Available literature reports on ultrasound diagnostics of vascular rings are sporadic - they represent an illustration of their own experience or a report on isolated clinical cases, where the authors demonstrate intermediate (non-standard) echocardiographic sections that only allow one to suspect the established pathology (Mądry W., Zacharska-Kokot E., Karolczak M.A. Methodology of echocardiographic analysis of morphological variations of the aortic arch and its branches in children - own experience. J. Ultrason. 2019; 19 (76): 24-42; Bhat Y., Alhabshan F., Almesned A., Alqwaee A. Can echocardiography aid in diagnosing vascular rings? Cureus. 2023; 15 (12): e50899; de Souza G.G., Guimarães A.F.M., Wang R. et al. Role of transthoracic echocardiography in the diagnosis of double aortic arch. Arq. Bras. Cardiol.: Imagem. Сardiovasc. 2022; 35(1): eabc267; Bjorkman K.R., Thattaliyath B., Ashwath R. The tracheal sweep: novel use of tracheal landmark in echocardiography to determine aortic arch sidedness. Authorea. September 28, 2023; He X., Chen J., Li G. Study on the views and methods of ultrasonic screening and diagnosis for abnormal aortic arch in infants. Cardiovasc. Ultrasound. 2021; 19 (1): 8).

The closest to the claimed method is a method of the same purpose, which provides for a combination of three projections obtained from the suprasternal and high parasternal approaches in the parasagittal and frontal planes (Bhat Y., Alhabshan F., Almesned A. et al. Can echocardiography aid in diagnosing vascular rings? Cureus. 2023; 15 (12): e50899). The first two projections are reproduced from the classical suprasternal approach: the 1st projection, with the sensor mark oriented at 3 o'clock on the conventional clock face, visualizes the course and bifurcation of the first brachiocephalic vessel and allows one to suspect an aberrant course of the subclavian artery; The 2nd projection is a continuous parasagittal scan along the long axis of the aortic arch (the sensor mark is directed at 12 o'clock), during which the left aortic arch is visualized on the left, and the right one - on the right of the tracheal cartilages. It is used to determine the lateralization of the aortic arch. The third projection is obtained from a high parasternal approach with a transverse orientation of the sensor and a frontal tilt of the scanning plane behind the sternum, which allows us to establish the relative position between the descending aorta, the left and right inferior pulmonary veins and the vertebral body.

Despite all the advantages of the technical solution, this method of visualization is not informative and accurate enough. Reproduction of the first brachiocephalic vessel may be difficult in patients with a certain type of branching. In the case of an atypical origin of the vertebral artery from the common carotid artery or in the case of the origin of the common carotid arteries by one trunk, the bifurcation of the first branch will mask the aberrant course of the subclavian artery. A double aortic arch with two functioning arches or an atresia area between the left common carotid and subclavian arteries will also not have a bifurcation of the first vessel. In the case of a double aortic arch with atresia of the distal segment of the left arch, this projection in combination with the two subsequent ones will not allow differentiating it from the corresponding variant of the right arch. In parasagittal scanning along the long axis of the aortic arch, identification of the arch and ductus arteriosus position is based on the operator's subjective impression, since the aortic arch/ductus arteriosus and trachea are not simultaneously visible on parasagittal sections. The use of this projection is limited in the case of a break/atresia or hypoplasia of the aortic arch. All this significantly reduces the informativeness of the method. In addition, objective characterization of the spatial anatomy of the aortic arch and its branches is difficult. Sagittal scanning does not display the syntopy of the vessels under study.

The technical problem of the invention is to increase the information content of the ultrasound assessment of the anatomical and topographic state of the aortic arch and its branches, allowing for the diagnosis of anomalies of the aortic arch that form a vascular ring.

The technical result of the proposed method is an increase in the accuracy of assessing the spatial anatomy of the aortic arch and its branches.

The specified technical result is achieved by the fact that during the course of an echocardiographic study to assess the anatomy of the aortic arch in newborns and young children, in addition to standard projections, a combination of two consecutive transverse sections of the upper mediastinum region is reproduced.

The method is carried out as follows.

In neonates and young children, when performing transthoracic echocardiography using a sector phased ultrasound transducer used for cardiological studies in pediatrics and neonatology (recommended frequency range 4–12, 3–8 MHz), from a high parasternal approach by orienting the transducer mark at 3 o'clock on the conventional clock face (the patient's left shoulder) in the cranial direction, transverse scanning of the upper mediastinum is performed, during which a combination of two consecutive sections passing through the trachea is obtained and evaluated:

1st — at the level of the transverse aortic arch and the arterial duct, if there is blood flow in it. The initial reference point for obtaining this projection can be visualization of the main vessels (aorta, pulmonary artery) from a high parasternal approach along the short axis, from where the required projection can be reproduced using a slight tilt of the acoustic beam toward the head. Lateralization of the aortic arch and arterial duct is established relative to the trachea as follows: when the aortic arch/arterial duct is located to the left of the trachea, the left arch and left arterial duct are diagnosed; when the aortic arch and arterial duct are visualized to the right of the trachea, the right arch and right arterial duct are diagnosed; with bilateral imaging, a double aortic arch is diagnosed. The trachea is identified as a hyperechoic ring that produces an acoustic shadow along the course of the ultrasound beam; in the color Doppler mapping mode, the reference point is the appearance of a “flickering artifact” in the lumen of the trachea and distally, along the acoustic shadow;

2nd - at the level of the origin of the brachiocephalic arteries directly from the aortic arch. This section is obtained by slightly shifting the ultrasound sensor in the cranial direction from the previous projection; it serves to determine the number and relative diameter of the brachiocephalic arteries, as well as their relative position with the trachea. The section is assessed as follows: when visualizing three brachiocephalic arteries (the first has a slightly larger diameter) located along a straight line to the left of the trachea, an aberrant course of the right subclavian artery is excluded, which is a normal variant; when detecting three brachiocephalic arteries of relatively equal diameter located along a straight line at an equal distance from each other to the left or right of the trachea, an aberrant course of the subclavian artery is diagnosed; with a mirror-symmetrical arrangement of the four brachiocephalic arteries relative to the trachea, which form the angles of an isosceles trapezoid, the anatomy of the double aortic arch is differentiated from the right arch with a mirror-symmetrical type of branching.

Example 1

Newborn A., 1 day old, was admitted to the neonatal and premature infants intensive care unit for examination and verification of a prenatally detected aortic arch anomaly. Where, during a transthoracic echocardiographic examination using the proposed method, a double vascular ring around the trachea and esophagus formed by a double aortic arch and the left arterial duct was diagnosed. The sensor was installed in a high parasternal position with the marker oriented toward the patient's left shoulder and, using a small amplitude of sensor movement in the cranial direction, a section was sequentially reproduced first at the level of the transverse aortic arch, on which the right and left (smaller diameter) aortic arches, respectively, as well as the left patent arterial duct were visualized to the right and left of the trachea; then a projection at the level of the origin of the brachiocephalic arteries, which demonstrated a mirror-symmetrical arrangement of the vessels relative to the trachea. During preoperative preparation, the ultrasound diagnosis of double aortic arch was confirmed by multislice computed tomography angiography of vessels (MSCT-AG), which, in addition to the main diagnosis, showed compression of the trachea and esophagus.

Example 2

Patient V., 2 years old. According to the anamnesis, a heart murmur was heard at the age of 6 months. Based on echocardiography performed at the place of residence, a coronary-pulmonary fistula was suspected. According to the mother, there were no symptoms of swallowing and/or breathing disorders. Based on the data of standard transthoracic echocardiography obtained during parasagittal scanning from the suprasternal approach, a right aortic arch with a mirror-image type of branching was suspected. The proposed method was used to verify the anatomy of the defect. When reproducing a cross-section at the level of the aortic arch, the right aortic arch was visualized, from which the brachiocephalic vessel branched off to the left. A section at the level of the branching of the brachiocephalic arteries from the arch demonstrated a pathognomonic sign of the anatomy of a double aortic arch - a mirror-symmetrical arrangement of the vessels relative to the trachea. This allowed us to establish a preliminary diagnosis: a vascular ring around the trachea and esophagus, formed by a double aortic arch with a section of atresia of the left arch. The anatomy of the defect established during transthoracic echocardiography was confirmed by MSCT data and subsequently verified intraoperatively.

Example 3

Patient D., 3 months old, arrived to clarify the anatomy of the defect. It is known from the anamnesis that the congenital heart defect (CHD) is a vascular ring formed by the right aortic arch and the left arterial duct, diagnosed in the second trimester of pregnancy. During transthoracic echocardiography using two transverse projections of the upper mediastinum, in which the aortic arch was visualized to the right of the trachea, while the three brachiocephalic vessels extending from the arch had a relatively equal diameter, it was possible not only to verify the prenatal diagnosis of the right aortic arch, but also to diagnose an aberrant origin of the left subclavian artery from Kommerell's diverticulum, which made it possible to detail the anatomy of the CHD. The anatomy of the defect, described according to the echocardiographic study data, was completely consistent with the intraoperative picture.

The proposed method allows, in real time, using ultrasound examination, to obtain a sufficient amount of diagnostic information about the spatial anatomy of the aortic arch and its branches in newborns and young children, both in the norm and with various congenital anomalies of the aortic arch that form a vascular ring, which in practical terms will help to determine adequate tactics for managing such patients, and, if necessary, the scope of surgical intervention.

Thus, the use of the proposed method, in comparison with the prototype, provides a more detailed and complete diagnosis of various anomalies of the position and branching of the aortic arch in newborns and young children.

Claims (1)

A method for ultrasound diagnostics of abnormalities in the position of the aortic arch and its branches in newborns and young children, consisting in the fact that an ultrasound examination (US) is performed in the upper mediastinum region from the parasternal approach with the sensor marker oriented at 3 o'clock on a conventional clock face, continuous transverse scanning is performed in the cranial direction to obtain two successive sections passing through the trachea: at the level of the transverse aortic arch and the ductus arteriosus, at the level of the origin of the brachiocephalic arteries (BA) directly from the aortic arch; when determining the aortic arch and the ductus arteriosus to the left of the trachea, the left aortic arch and the left ductus arteriosus are diagnosed, when determining the aortic arch and the ductus arteriosus to the right of the trachea, the right aortic arch and the right ductus arteriosus are diagnosed, when determining the aortic arch on both sides of the trachea, a double aortic arch is diagnosed; when three BA are identified, located along a straight line to the left of the trachea, and the first BA has the largest diameter, an aberrant course of the right subclavian artery is excluded; when three BA of relatively equal diameter are detected, located along a straight line at an equal distance from each other to the left or right of the trachea, an aberrant course of the subclavian artery is diagnosed; when the BA are located in a mirror-symmetrical position relative to the trachea, a double aortic arch is diagnosed.