Features of Treatment of Children with Extrahepatic Portal Hypertension and Unsatisfactory Results of Previously Performed Surgical Corrections

The dissertation by Averyanova Y.V. is devoted to the optimization of the treatment strategy in children with extrahepatic portal hypertension (EPH) in whom previously performed surgical corrections have proved unsatisfactory. The research focuses on the assessment of the regional venous system, the identification of additional damage to the vessels of the portal venous system, and the substantiation of the effectiveness of various treatment methods — including comprehensive vascular therapy, staged endoscopic sclerotherapy, and endovascular interventions. Special attention is given to the phenomenon of insufficiency of the formed shunts, its pathogenesis, and the algorithms for managing this category of patients.

Relevance of the Topic

Despite the progress achieved in recent decades in the treatment of children with extrahepatic portal hypertension (EPH), the question of the strategy for managing patients with unsatisfactory results of previously performed surgical corrections remains open.

Palliative operations and therapeutic maneuvers employed for the control or prevention of complications of EPH still account for a significant proportion of surgical practice in our country. These types of surgical treatment not only fail to prevent the progression of the disease and its complications but also lead to progressive deterioration of the vessels of the portal venous system. The features of the regional venous system in children with EPH who have undergone palliative operations and therapeutic maneuvers, as well as their influence on the choice and outcome of subsequent reconstructive operations, have been insufficiently studied.

The algorithm for examining children with EPH was developed and introduced into practice long ago. A large number of works are devoted to methods of investigation of the venous system in EPH in children before and after surgical treatment (Nikitina E.A., 1986; Senyakovich V.M., 1986; Filchagova O.D., 1994; Razumovsky A.Yu., 1995; Drozdov A.V., 2002; Orloff M.J., 2002; Maksoud J.G., 1994). Despite this, little attention has been paid to studying the diagnostic capabilities of ultrasound and Dopplerography in the mode of color mapping and digital subtraction angiography when verifying various types of damage to the regional venous system. Identifying additional lesions of the venous system is important for determining the type of surgical treatment, especially in previously operated patients with EPH.

A special group is represented by patients with EPH who have undergone shunt operations but in whom pronounced clinical manifestations of the disease of varying degree have persisted. This condition has been designated by us as shunt insufficiency. The pathogenesis and prerequisites for the formation of shunt insufficiency are unclear and require further investigation.

At present, there are no clear concepts regarding the strategy for managing this category of patients: the possibilities of application and effectiveness of conservative therapy, staged endoscopic sclerotherapy (ES) of varicose dilated esophageal veins (DEV), and endovascular treatment methods, as well as the indications and timing for performing repeated reconstructive operations, have not been determined.

Objective: optimization of the treatment strategy in children with unsatisfactory results of surgical treatment of extrahepatic portal hypertension.

Research Tasks:

1. To study the frequency and nature of damage to the regional venous system in children with unsatisfactory results of surgical treatment of extrahepatic portal hypertension.

2. To investigate the reliability, informativeness, and specificity of digital subtraction angiography and ultrasound with Dopplerography in the mode of color mapping of blood flow when verifying various types of damage to the regional venous system.

3. To identify pathogenetic prerequisites for the formation of insufficiency of vascular anastomoses.

4. To determine the possibilities of application and effectiveness of comprehensive vascular therapy, staged endoscopic sclerotherapy of varicose dilated esophageal veins, and endovascular treatment methods in children with insufficiency of vascular anastomoses.

5. To improve the strategy of surgical treatment and rehabilitation of children with unsatisfactory results of surgical treatment of extrahepatic portal hypertension.

Scientific Novelty

The work provides an assessment of the condition of the regional venous system in children with unsatisfactory results of surgical treatment of extrahepatic portal hypertension. It has been confirmed that palliative and ineffective shunt operations in children with extrahepatic portal hypertension lead to the formation of additional damage to the regional venous system. The latter were identified in 52% of children who underwent palliative operations. In patients with absence of shunt function, in 16% of cases, alongside local changes in the vascular system (anastomotic thromboses), generalized types of damage were discovered (total thromboses and diffuse postthrombotic changes of the portal venous system (PVS)).

A comparative analysis of the capabilities of digital subtraction angiography and ultrasound with Dopplerography in the mode of color mapping of blood flow when verifying damage to the regional venous system has been conducted. It has been established that these two methods possess different informativeness, reliability, and specificity when detecting various types of damage to the venous system.

For the first time, a detailed assessment has been given of the condition referred to as insufficiency of the formed shunt function, and an algorithm for the treatment of this category of patients has been developed. It has been determined that in children with EPH, the pathogenetic basis for the formation of insufficiency of vascular anastomoses is local phlebitis or postthrombotic changes of the venous system of varying extent.

The effectiveness of the application of etiotropic vascular therapy in children with damage to the main vessels of the portal venous system has been demonstrated. It has been found that in patients with shunt insufficiency, clinical effectiveness is determined by the restoration of vascular anastomosis function with regression of EPH symptoms within a period of up to one year from the beginning of treatment and amounts to 90%.

The possibility of application and effectiveness of endoscopic sclerotherapy of varicose dilated esophageal veins in children with shunt insufficiency has been determined.

The feasibility and effectiveness of the application of "atypical" types of shunt operations in children with additional damage and/or anomalies of the structure of the regional venous system have been demonstrated.

Practical Significance

It has been proven that damage to the regional venous system develops in 37.8% of patients with EPH and unsatisfactory results of performed operations. This circumstance underscores the necessity of comprehensive examination of previously operated patients with EPH for the optimal choice of a subsequent shunt operation, taking into account the features of the regional venous system.

An algorithm for the treatment strategy of patients with shunt insufficiency has been developed. It has been found that the application of comprehensive vascular therapy aimed at eliminating processes of endogenous inflammation and thrombus formation allows for normalization of vascular anastomosis function with regression of disease symptoms.

It has been confirmed that the application of staged endoscopic sclerotherapy in patients with shunt insufficiency is effective in terms of reducing the degree of DEV and decreasing the risk of development of gastroesophageal bleeding until adequate decompression of the portal venous system is restored. It has been found that comprehensive vascular therapy and treatment aimed at eliminating inflammatory phenomena of the upper gastrointestinal tract allow for improvement of the results of ES, as well as a reduction in the risk of development of postmanipulative complications.

The ineffectiveness and inexpediency of the application of therapeutic maneuvers (staged endoscopic sclerotherapy, endovascular treatment methods) in patients with absence of shunt function have been demonstrated.

Given the moderate informativeness of ultrasound and DH with color mapping of blood flow when verifying thromboses of vascular shunts, the necessity of constant dynamic monitoring with assessment of the severity of EPH symptoms in patients with shunt insufficiency has been indicated. In the case of progression of at least one of the disease symptoms or their absence of regression over the course of a year in this category of patients, diagnostic angiography must be performed to determine the function of the vascular anastomosis.