Coagulation Disorders in Infective Endocarditis: Role of Pathogens, Biomarkers, Antithrombotic Therapy (Systematic Review)

The issue of antithrombotic therapy in patients with infective endocarditis has been studied for over 75 years. During that time studying of pathogenesis of the disease and its embolic complications, lead to the introduction of the concept of “immunothrombosis”. That mechanism allows infective agents (mostly bacteria) to be cloaked from the immune system and to multiply freely, leading to growth of vegetation, thus resulting in higher chance of fragmentation. Small-scale experimental and clinical studies on the correction of hemostatic disorders in infective endocarditis, that were performed in 20th century, didn’t show any significant results, that could affect clinical practice. However, reinterpretation of available data on coagulative system will allow to have elements of hemostasis as an application point in treating infective endocarditis. The article will discuss latest insights on the role of hemostasis system in pathophysisology of infective endocarditis, its effects on the development of the embolic complications, perspectives for diagnostics and treatment

Infective endocarditis and COVID-19: the impact of SARS-CoV-2 infection on diagnostics, course, and prognosis

Aim. To study the impact of coronavirus disease 2019 (COVID-19) pandemic on hospitalization rates, diagnosis, and outcomes of infective endocarditis (IE) with a subanalysis of IE course in combination with COVID-19.Material and methods. This prospective cohort study included 168 patients with definite or probable IE (DUKE 2015) hospitalized in the V.V. Vinogradov City Clinical Hospital from July 2017 to July 2022. All patients underwent a conventional examination in accordance with current clinical guidelines. We studied clinical, paraclinical and etiological parameters, as well as outcomes.Two clinical observations of the combination of IE and COVID-19 are presented.Results. When assessing the local registry of patients with IE, a trend towards an increase in hospitalizations rate of IE in 2021-2022 was shown, with a decrease during the period of long-term lockdowns in Moscow and a subsequent surge after their cancellation. Patients with IE during the COVID-19 pandemic had a more favorable clinical profile, a 2-fold increase in IE diagnosis (due to late hospitalization), frequent detection of Staphylococcus aureus MSSA (32,6%), and frequent surgical treatment (up to 87,6% with a combination of IE and COVID-19), as well as high in-hospital mortality, but without a tendency to increase (30,4%). Clinical observations of IE and COVID-19 combination are presented, which demonstrates the contribution of COVID-19 as the only risk factor for native tricuspid valve IE in a patient without predisposing causes, as well as a factor in the unfavorable prognosis for native aortic valve IE after the addition of COVID-19, which led to lethal outcome.Conclusion. The present study demonstrates the profile of patients with IE and COVID-19 depending on the epidemiological situation of COVID-19 and the association with SARS-CoV-2 infection. The data obtained make it possible to discuss the potential relationship between COVID-19 and IE. The "endocarditis team" determines the timely implementation of surgery and the absence of an increase in inhospital mortality, regardless of the epidemiological situation

Clinical and diagnostic value of including PCR blood test in the traditional algorithm for identifying causative agents of infective endocarditis: a cohort study of 124 patients

Background. If infective endocarditis (IE) is suspected, the determination of the etiology is of fundamental importance for the verification of the disease and the appointment of effective therapy. Microbiological diagnostic features are important, but they often need to be supplemented by culture-independent studies of pathological agents. Aim. To investigate of the diagnostic advantage and value of quantitative analysis of molecular biological methods (polymerase chain reaction PCR, sequencing) in addition to microbiological examination of whole venous blood in IE. Materials and methods. We examined 124 patients with suspected or significant IE (DUKE 2015) hospitalized in the Vinogradov City Clinical Hospital (20152021). All patients underwent parallel microbiological (cultural) and molecular biological (PCR or PCR followed by sequencing) examination of venous whole blood samples. Results. The introduction of an early parallel PCR study into the algorithm for the etiological diagnosis of IE made it possible to obtain an additional advantage in 43/124 (34.7%) patients, which made it possible to exclude unreliable results in the determination of CoNS skin commensals and pathogens atypical for IE or contamination and identify the true pathogens, and also for the first time to isolate the etiopathogenetic pathogen with a negative microbiological study. It was shown that in IE associated with CoNS, the association with the disease was confirmed by PCR in 21.4% (3/14) and refuted in 71.4% (10/14). The coincidence of the results of microbiological and PCR studies of blood samples was obtained only in 35/95 (36.8%). Positive results of PCR analysis of blood of biological material with negative results of culture were obtained in 22/51 (43.1%), of which 2/22 (9.0%) were able to confirm the presence of Bartonella spp DNA. The presented complex algorithm made it possible to significantly increase the possibility of intravital identification of the pathogen in the blood from 58.9 to 76.6%. IE with unknown etiology was present in 29/124 (23.4%) patients. A parallel PCR study allowed timely correction of antibiotic therapy in 43/124 (34.7%) patients. Conclusion. Expansion of indications for the use of PCR studies, primarily whole venous blood samples, is justified, not only in IE with negative results of microbiological examination, but also as a control method for the reliability of the results of traditional (cultural) diagnostic methods

A Case Report of Differential Diagnosis of Causes of Severe Valvular Heart Disease (Takayasu's Arteritis, Infective Endocarditis and Myxomatous Degeneration) with the Key Role of Histological and PCR Examination

Aortic valve lesion is a common and may have diverse causes, from degenerative, congenital and infectious diseases to autoimmune conditions. We present a rare case of Takayasu arteritis and severe heart lesion due to the myxomatous degeneration of the aortic and mitral valves associated with development of infective endocarditis (IE) complicated by abscess, fistula, valve perforation and recurrent acute decompensated heart failure in a young female patient. A combined use of histopathological and PCR analyses of valve tissues was critically important for differential diagnosis of the valve lesions, as it made it possible to identify the true cause of the disease. The presence of Takayasu arteritis has played an indirect role by creating conditions for the development of immunosuppression and determining the disease severity and its progression

Modern trends in identification of causative agents in infective endocarditis

Advances in the diagnosis and treatment of patients with infectious endocarditis are limited by the high frequency of cases with an unknown etiology and imperfection of microbiological (cultural) methods. To overcome these problems new approaches to the identification of infectious endocarditis pathogens were introduced, which allowed achieving certain positive results. However, it should be noted that despite the wide variety of diagnostic tools currently used, there is no ideal method for etiological laboratory diagnosis of infectious endocarditis. The article discusses the features and place of immunochemical, molecular biological (MALDI-TOF MS, real-time PCR, sequencing, in situ fluorescence hybridization, metagenomic methods, etc.), immunohistochemical methods, and their advantages and limitations