nonbacterial thrombotic endocarditis

Introduction

Introduction to non-bacterial thrombotic endocarditis Non-bacterial thromboembolic endocarditis (NBTE) has been called "cachexia endocarditis" or "consumptive endocarditis" because it is often associated with chronic wasting disease, malignant tumors. It is associated with various diseases such as disseminated intravascular coagulation (DIC). basic knowledge The proportion of illness: 0.005% Susceptible people: more common in middle-aged Mode of infection: non-infectious Complications: cerebral embolism myocardial infarction

Cause

The cause of non-bacterial thrombotic endocarditis

(1) Causes of the disease

The etiology has not yet been elucidated. Gross et al believe that rheumatic valvular disease is an important cause of non-bacterial thrombotic endocarditis. Allen and Sirota believe that allergic reactions and vitamin C deficiency are prone to the disease. Williams believes that allergic reactions and circulating immunity The complex is the immunological basis of valve damage.

(two) pathogenesis

1. Mechanisms Williams believes that allergic reactions and circulating immune complexes are the immunological basis of valvular lesions. Recently, Mcray and Warlor thought that malignant tumors (especially gastric cancer, pancreatic cancer and lung cancer) and DIC hypercoagulable state, high blood clotting fluid The turbulence formed by the valve closure line is an important factor in the formation of thrombosis, tumor mucin and thrombocytosis, increased levels of fibrinogen or coagulation factors V, VII, XI and IX, increased fibrinolytic products, accelerated fibrin decomposition and The pre-clotting substances produced by tumor cells are important causes of thrombosis in the valve. Therefore, any disease that can produce primary or secondary hypercoagulable state is the cause of non-bacterial thrombotic endocarditis. And pathological basis.

Non-bacterial thrombotic endocarditis can involve any heart valve, mainly affecting the mitral valve and aortic valve. The second and third tricuspid sputum are mostly located in the atrial surface. The aortic valve and the pulmonary valve are mostly located in the ventricle. The main pathological change of non-bacterial thrombotic endocarditis is the formation of aseptic neoplasms on the valve. The early changes of valvular collagen occur under the influence of allergic reactions, vitamin deficiency, hemodynamic damage and aging. Degenerative changes and matrix edema, followed by partial exfoliation of the intima of the valve, expose collagen and matrix to the bloodstream. When the antibody is in a hypercoagulable state, platelets and the like are easily attached to the surface to form non-bacterial thrombotic neoplasms. The lesions are more superficial, and there is often no inflammatory reaction in the local area. Once the neoplasms fall off, the signs of arterial embolism can be generated.

2. Pathological changes Allen and Sirota divide the pathological manifestations of non-bacterial thrombotic endocarditis into five types:

Type I: a single small sickle lesion, <3mm in diameter, light brown to dark brown, more adherent to the valve.

Type II: Single large scorpion, >3 mm in diameter, yellow-brown, granular, adhering to the valve.

Type III: multiple small sickle lesions, 1 to 3 mm in diameter, fragile, often arranged in a beaded shape along the valve closure line.

Type VI: multiple large sputum lesions, all > 3mm, soft and brittle, size, density, and color.

Type V: old type (healing type), with epithelial cell coverage on the surface, color, density similar to attached valve tissue, early pathological changes of the disease for valve gum cause allergic reaction, vitamin C deficiency, hemodynamic damage and aging and other factors Under the influence, degenerative changes and matrix edema occur, followed by partial exfoliation of the intima of the valve, exposing collagen and matrix to the bloodstream, especially when the body is in a hypercoagulable state, which tends to cause platelets and the like to adhere to the collagen tissue, resulting in Non-bacterial thrombotic neoplasms, often without inflammatory reactions, lesions are more superficial, once the sputum organisms fall off can produce signs of arterial embolism.

Prevention

Non-bacterial thrombotic endocarditis prevention

Active prevention and treatment of primary diseases, patients with old and frail, chronic wasting diseases, malignant tumors and other diseases should be carefully observed, early detection, early treatment.

In addition to NBTE, non-infective valvular vegetation (NIVV) has the following common conditions:

1. Systemic lupus erythematosus (SLE) As early as 1924, Libman and Sacks first reported that SLE can produce neoplasms in heart valves. In recent years, echocardiography confirmed that 18% to 40% of patients with SLE have NIVV, called Libman-Sacks. Endometritis, in which the mitral valve is most susceptible, followed by the aortic valve, the biopathological features of the sputum are generally 3 ~ 5mm, gray or pink, pea-like or flat, often adhered to the endocardium, Can be associated with thrombosis, fibrin under the microscope, fibrous tissue formation, platelet or thrombus adhesion, with a small amount of mononuclear cell infiltration.

(1) Clinical manifestations: mainly manifested as symptoms of SLE. In a few cases, systolic murmurs of mitral regurgitation may occur. If the aortic valve is involved, aortic regurgitation murmur may occur, and occasional sputum detachment may also cause body Corresponding signs of arterial embolization, a group of 50 SLE autopsy found that 10 cases of cerebral infarction, 5 cases related to Libman-Sacks endocarditis, obstructive obstruction, echocardiography, especially esophageal echocardiography is easier It has been found that the sputum on the valve has a definite diagnosis value, but sometimes it is difficult to distinguish it with SLE and SIE. If the plasma phospholipid level is increased, and the antigen-antibody reaction is more than SLE and Libman-Sacks endocarditis.

(2) The main treatment of primary disease, the larger sputum organisms advocate the use of anticoagulant therapy, commonly used warfarin, vinegar coumarin, but need to consider the risk of bleeding, its efficacy has yet to be further confirmed, if Surgical treatment is required if the valve is severely closed, but this is rare.

2. Primary antiphospholipide syndrome (PAPS) This syndrome is associated with the presence of phospholipid antibodies in serum. Patients often have recurrent miscarriage, thrombocytopenia and repeated arteriovenous embolization. If the patient prolongs prothrombin time However, the possibility of PAPS should be considered when adding normal plasma can not be corrected. The serum phospholipid antibody is positive in this syndrome, which is of great value for diagnosis. Although the serum phospholipid antibody of SLE patients can also be positive, it is also positive for anti-double-stranded DNA antibody. Sm antibody and anti-nuclear antibody were positive for identification, while PAPS serum cardiolipid antibody was significantly increased. The valvular sputum of this disease mainly relied on echocardiography. The size of common sputum was 2-6 mm, and the disease rarely caused valve function. obstacle.

Treatment: Similar to SLE and Libman-Sacks endocarditis.

Complication

Non-bacterial thrombotic endocarditis complications Complications, brain embolism, myocardial infarction

Embolism: non-bacterial neoplasms of non-bacterial thrombotic endocarditis are more brittle, and the lesions are superficial. Once they fall off, arterial embolism can occur. For example, cerebral embolism can cause hemiplegia. Coronary embolism can cause myocardial ischemia or myocardial ischemia. Infarction; renal artery embolism can produce renal colic, etc., but due to the small non-bacterial neoplasm in this disease, the thrombosis formed is also small, so that most cases have thrombosis but no obvious clinical symptoms, resulting in missed diagnosis before birth. .

Symptom

Non-bacterial thrombotic endocarditis symptoms Common symptoms Elderly hyperviscosity Heart murmur Myocardial infarction

The disease is more common in middle-aged and elderly people, accounting for 79.2% of 50 years old, but it can be seen in any age group. The disease lacks specific symptoms and signs. Auscultation does not help the diagnosis of this disease. Only 1/3 of cases can have heart murmur. Most of them are located at the lower edge of the sternum, and the apex of the apex is transmitted. The murmur is soft. Half of the cases may have embolic symptoms. For example, cerebral embolism may cause hemiplegia. Coronary embolism may cause myocardial ischemia or myocardial infarction. Renal artery embolism may cause renal colic. Etc., but because of the small sputum of non-bacterial thrombotic endocarditis, the embolus is small, so it rarely causes aortic and intermediate arterial embolism, mostly small arterial embolism, so most cases have embolism and no symptoms. Therefore, many cases were not diagnosed before birth.

Mcray proposed a triad for clinical diagnosis of non-bacterial thrombotic endocarditis:

1. A disease in which non-bacterial thrombotic endocarditis can occur.

2. The heart has a murmur or a new murmur or the original murmur changes.

3. The body has multiple embolisms.

Examine

Non-bacterial thrombotic endocarditis

DIC laboratory test results are positive, as well as multiple blood cultures are negative, which is helpful for the diagnosis of this disease.

Echocardiography may find large sputum of NBTE, which is helpful for diagnosis, but most cases are difficult to detect because the sputum is too small. In addition, 111 indium (111In) platelet marker imaging, 99 (99Tc) stannous Although pyrophosphate, 67 gallium (67Ga) citrate and other radionuclide imaging have been reported, its value has yet to be evaluated, and the diagnostic value of CT and cardiac gate magnetic resonance imaging remains to be studied.

Diagnosis

Diagnosis and identification of non-bacterial thrombotic endocarditis

In addition, venous thrombosis, DIC laboratory diagnosis and multiple blood culture negative, all contribute to the diagnosis of non-bacterial thrombotic endocarditis, if combined with UCG found that neoplasms are more conducive to diagnosis.

The disease should be differentiated from acute infective endocarditis, subacute infective endocarditis, Loffer endocarditis, Libman-Sacks endocarditis and other diseases.

Was this article helpful?

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.