The state of the biliary tract in patients with chronic heart failure

The dissertation is devoted to the study of morphological and functional changes of the biliary tract in patients with chronic heart failure of stages II–III that developed against the background of various cardiac pathologies — rheumatic heart defects, ischemic heart disease, and dilated cardiomyopathy. The work carries out a comprehensive clinical and instrumental examination of patients using ultrasound, oral cholecystography, multiphasic fractional duodenal intubation, liver scintigraphy, computer sonometry, and biochemical study of bile. It analyses the frequency and character of changes of the gallbladder and biliary tract depending on the stage of circulatory insufficiency and the nature of the underlying disease, compares the diagnostic capabilities of different methods, and evaluates the influence of cardiac therapy on the functional state of the biliary system. The data obtained indicate the progression of morphological and functional disorders of the biliary tract with the deepening of circulatory insufficiency and the development of irreversible changes in patients with severe cardiac pathology.

RELEVANCE OF THE PROBLEM

Ultrasound examination (US) is a non-invasive method that is safe for patients; its use is not associated with ionizing radiation, does not require the administration of contrast agents or a specially equipped room, and its application allows repeated dynamic monitoring. However, until now the literature contains only isolated reports on the use of ultrasound to study the macrostructure of the gallbladder (GB) in patients with circulatory insufficiency; the functional state of the biliary system in these patients has not been studied in relation to the nature of the cardiac pathology. Identifying the character and frequency of secondary dyskinesia of the biliary tract in patients with chronic circulatory insufficiency is of great importance for assessing the prognosis of this disorder of inter-organ relationships, including with regard to the possible development of cholelithiasis (97).

The available studies describing changes in the biliary tract during ultrasound examination in patients with heart failure that developed against the background of various cardiac pathologies do not adequately reflect the problem and are contradictory (32, 44, 81, 94, 96, 101). The ultrasound diagnostic criteria for lesions of the biliary system reported in the literature are also ambiguous (89, 132). There is no comparative analysis of the interpretation of the changes revealed by ultrasound with the data of other examination methods in chronic circulatory insufficiency. The comparative capabilities of the ultrasound method and other methods of investigation (cholecystography, multiphasic fractional duodenal intubation, biochemical study of bile) in assessing the state of the biliary system in patients with chronic circulatory insufficiency of stage II–III have not been studied, and the place of the ultrasound method of examining the biliary tract in the complex investigation of patients with stage II–III circulatory insufficiency has not been defined.

AIM OF THE STUDY

To investigate the features of morphological and functional changes of the biliary tract in patients with stage II–III circulatory insufficiency developing against the background of various cardiac pathologies.

OBJECTIVES OF THE STUDY

1. To establish the frequency and character of changes in the gallbladder and biliary tract according to ultrasound data in patients with stage II A, II B, and III circulatory insufficiency that developed against the background of combined rheumatic mitral heart disease, combined rheumatic mitral-aortic heart disease, ischemic heart disease, and dilated cardiomyopathy.

2. To establish the frequency and character of functional disorders of the biliary system according to ultrasound data in patients with stage II A, II B, and III circulatory insufficiency that developed against the background of combined rheumatic mitral heart disease, combined rheumatic mitral-aortic heart disease, ischemic heart disease, and dilated cardiomyopathy.

3. To analyse the mechanisms underlying the formation of morphological and functional changes of the gallbladder and biliary tract in patients with stage II A, II B, and III circulatory insufficiency against the background of combined rheumatic mitral heart disease, combined rheumatic mitral-aortic heart disease, ischemic heart disease, and dilated cardiomyopathy.

4. To carry out a comparative analysis of the value of different methods of studying the state of the biliary system (oral cholecystography, multiphasic fractional duodenal intubation, biochemical study of bile, and ultrasound examination) in patients with stage II A, II B, and III circulatory insufficiency.

5. To evaluate the influence of complex therapy of stage II–III circulatory insufficiency on the anatomical and functional state of the gallbladder and biliary tract.

6. To define the place of the ultrasound method in the complex investigation of patients with circulatory insufficiency.

SCIENTIFIC NOVELTY

For the first time, a comprehensive clinical and instrumental study of the biliary system has been performed in patients with different stages of circulatory insufficiency complicating the course of combined rheumatic mitral heart disease, combined rheumatic mitral-aortic heart disease, ischemic heart disease, and dilated cardiomyopathy. For the first time, a comparative analysis of morphological and functional changes of the gallbladder and biliary tract has been carried out in patients with different stages of circulatory insufficiency against the background of various heart diseases. The relationship between the severity and frequency of changes of the gallbladder and biliary tract and the features of the clinical course of the underlying disease, central hemodynamic parameters, and markers of clinical and laboratory syndromes of cytolysis and cholestasis has been studied. For the first time, it has been shown that the severity of morphological and functional changes of the biliary tract at the early stages of circulatory insufficiency is determined to a greater extent by the presence of the underlying disease — cardiac pathology — while at the late stages it is determined by mechanisms directly related to chronic heart failure. A clear relationship has been demonstrated between the depth of circulatory insufficiency, the severity of dyscholia, and consequently the frequency and severity of morphological and functional changes of the gallbladder and biliary tract. General criteria have been identified for assessing morphological and functional changes of the gallbladder and biliary tract in patients with different stages of circulatory insufficiency and the underlying diseases. The leading role of ultrasound methods in the diagnosis of morphological and functional changes of the gallbladder and biliary tract in patients with different stages of circulatory insufficiency has been demonstrated. It has been proved that cardiac therapy, accompanied by improvement of central hemodynamics, contributes to improvement of the functional state of the gallbladder and biliary tract. It has been revealed that the degree of improvement of the functional state is more pronounced in patients with earlier stages of circulatory insufficiency and is least pronounced in patients with stage III.

PRACTICAL SIGNIFICANCE

Comparison of different methods of studying the anatomical and functional state of the biliary system in patients with circulatory insufficiency (ultrasound, oral cholecystography, multiphasic fractional duodenal intubation, biochemical study of gallbladder bile) has demonstrated the advantages of the ultrasound method. In patients with chronic circulatory insufficiency, ultrasound examination can be recommended as the main method for diagnosing lesions of the gallbladder and biliary tract. The obtained results indicate that therapy aimed at reducing the severity of circulatory insufficiency and correcting hemodynamic disorders in patients with rheumatic heart defects, ischemic heart disease, and dilated cardiomyopathy contributes to improvement of the functional state of the biliary tract. The most pronounced positive dynamics is observed in patients at the early stages of circulatory insufficiency, while in patients with pronounced circulatory insufficiency the degree of positive changes is significantly lower. The data obtained indicate the development of irreversible changes of the biliary tract in patients with circulatory insufficiency, increasing as the cardiac pathology progresses. Metabolic disorders contribute to a pronounced disturbance of the colloidal stability of bile, with a marked increase in its lithogenicity; this is reflected in a significant decrease in the cholate-cholesterol ratio, which increases with the progression of circulatory insufficiency, and this effect contributes to disruption of the balance between the main components of bile. Based on the data obtained, it follows that virtually every patient with circulatory insufficiency can be regarded as having a risk factor for diseases of the gallbladder and biliary tract, including the development of gallstone disease. Accordingly, the combination of severe cardiac pathology complicated by circulatory insufficiency and a disease that in many cases requires surgical, often emergency, treatment carries a very poor prognosis. The above determines the need for monitoring and correction of the state of the biliary tract from the earliest stages of circulatory insufficiency. This approach will improve the general condition and working capacity of patients and reduce the costs of treating patients with circulatory insufficiency.

MAIN STATEMENTS SUBMITTED FOR DEFENCE

1. Changes in the gallbladder and biliary tract are detected in 70.7% of patients with stage II A circulatory insufficiency, in 89.7% of patients with stage II B circulatory insufficiency, and in 100% of persons with stage III circulatory insufficiency. They constitute a complex combination including manifestations of abdominal pain and dyspeptic syndromes, morphological changes and functional disorders of the gallbladder and biliary tract, and manifestations of dyscholia.

2. At stage II A of circulatory insufficiency, the most pronounced changes in the state of the gallbladder and biliary tract are found in patients with ischemic heart disease and post-infarction cardiosclerosis. This effect is due to the high frequency of lipid metabolism disorders, which is also a risk factor for biliary tract diseases. Less pronounced changes were observed in patients with combined mitral-aortic heart defects, who were characterised by significant hemodynamic disturbances. Slightly less pronounced changes were found in patients with combined mitral heart defects, in whom hemodynamic changes were less pronounced. The least degree of changes was characteristic of persons with dilated cardiomyopathy, who were characterised by a short duration of the disease, during which, apparently, the mechanisms of disturbance of the state of the gallbladder and biliary tract have not had time to develop.

3. In patients with stage II B and stage III circulatory insufficiency, a decrease in the role of the underlying disease in the formation of changes of the gallbladder and biliary tract and an increase in the significance of factors associated with the presence of circulatory insufficiency are observed. Owing to this effect, a convergence in the severity of changes of the gallbladder and biliary tract in patients with different heart diseases has been noted.

4. Comparison of different methods of studying the anatomical and functional state of the biliary system in patients with circulatory insufficiency (ultrasound, oral cholecystography, multiphasic fractional duodenal intubation, biochemical study of gallbladder bile) has demonstrated the advantages of the ultrasound method.

5. The pronounced morphological and functional changes of the gallbladder and biliary tract appear to be of a multifactorial nature. Thus, in patients with stage II A circulatory insufficiency, a tendency toward an increase in the bilirubin level in the gallbladder bile was noted, indicating congestive phenomena in the gallbladder and bile thickening at the early stages of circulatory insufficiency. At the same time, with the progression of circulatory insufficiency, a significant and reliable decrease in the average level of this indicator was observed. The decrease in bilirubin concentration indicates a disturbance of the concentrating function of the gallbladder and of pigment metabolism in the liver. In turn, damage to the gallbladder causes a decrease in the concentration of phospholipids and an increase in the concentration of cholesterol in the gallbladder bile. The observed changes are explained by bile stasis and reduced reabsorption of certain bile components by the gallbladder wall.

6. The metabolic disturbances in the hepatobiliary system described above promote a sharp disturbance of the colloidal stability of bile, with a marked increase in its lithogenicity; this is reflected in a significant decrease in the cholate-cholesterol ratio, which increases with the progression of circulatory insufficiency, contributing to disruption of the balance between the main components of bile — cholesterol, phospholipids, and bile acids — and cholesterol precipitates. These assumptions are confirmed by the marked and progressive increase in signs of gallbladder damage detected by ultrasound with the deepening of dyscholia revealed by biochemical examination.

7. Therapy aimed at reducing the severity of circulatory insufficiency and correcting hemodynamic disorders in patients with rheumatic heart defects, ischemic heart disease, and dilated cardiomyopathy contributes to improvement of the functional state of the gallbladder and biliary tract. The most pronounced positive dynamics is observed in patients at the early stages of circulatory insufficiency, while in patients with pronounced circulatory insufficiency the degree of positive changes is significantly lower. Accordingly, the severity of residual disorders predominates in patients with severe circulatory insufficiency. At the same time, in patients with stage II A circulatory insufficiency, a number of indicators approach the levels of parameters in the control group while retaining a tendency toward change. The obtained data indicate the development of irreversible changes of the biliary tract in patients with circulatory insufficiency, increasing as the cardiac pathology progresses.

IMPLEMENTATION INTO PRACTICE

The developed methods are used to assess the prognosis and determine the tactics of therapy for patients with chronic circulatory insufficiency in the cardiological, therapeutic, and gastroenterological departments of the Central Clinical Hospital No. 2 named after N.A. Semashko of JSC Russian Railways and of the Medical Sanitary Unit No. 33 in Moscow. The data are used in conducting classes with students and trainees of qualification and certification cycles at the Department of Propaedeutics of Internal Medicine of the Faculty of General Medicine and the Department of Gastroenterology of the Moscow State University of Medicine and Dentistry.

APPROBATION OF THE WORK

The materials of the dissertation were presented as poster reports at the Tenth Russian Gastroenterological Week (Moscow, 2004), at the scientific and practical conference dedicated to the 90th anniversary of the Central Clinical Hospital No. 2 named after N.A. Semashko of JSC Russian Railways (Moscow, 2004), at the Fifth Congress of the Society of Gastroenterologists of Russia and the XXXII Session of the Central Research Institute of Gastroenterology (Moscow, 2005), and at a joint meeting of the staff of the Departments of Propaedeutics of Internal Medicine and Gastroenterology and of Hospital Therapy No. 1 of the Moscow State University of Medicine and Dentistry (Moscow, 23 December 2004).

PUBLICATIONS

Four printed works have been published on the topic of the dissertation.

STRUCTURE AND VOLUME OF THE DISSERTATION

The dissertation consists of an introduction, five chapters, a conclusion, and a bibliography containing 105 domestic and 42 foreign sources. The dissertation is set out on 177 pages of typewritten text and is illustrated with 39 tables and 5 figures.