scholarly journals Control of Blood Coagulation by Hemocompatible Material Surfaces—A Review

2021 ◽  
Vol 8 (12) ◽  
pp. 215
Author(s):  
Janna Kuchinka ◽  
Christian Willems ◽  
Dmitry V. Telyshev ◽  
Thomas Groth
Keyword(s):  
Blood Coagulation ◽  
Medical Devices ◽  
Heart Valves ◽  
Blood Compatibility ◽  
Blood Platelets ◽  
Bleeding Risk ◽  
Ventricular Assist Devices ◽  
Coagulation System ◽  
Material Surfaces

Hemocompatibility of biomaterials in contact with the blood of patients is a prerequisite for the short- and long-term applications of medical devices such as cardiovascular stents, artificial heart valves, ventricular assist devices, catheters, blood linings and extracorporeal devices such as artificial kidneys (hemodialysis), extracorporeal membrane oxygenation (ECMO) and cardiopulmonary bypass. Although lower blood compatibility of materials and devices can be handled with systemic anticoagulation, its side effects, such as an increased bleeding risk, make materials that have a better hemocompatibility highly desirable, particularly in long-term applications. This review provides a short overview on the basic mechanisms of blood coagulation including plasmatic coagulation and blood platelets, as well as the activation of the complement system. Furthermore, a survey on concepts for tailoring the blood response of biomaterials to improve the hemocompatibility of medical devices is given which covers different approaches that either inhibit interaction of material surfaces with blood components completely or control the response of the coagulation system, blood platelets and leukocytes.

Clinical Application Of Blood Surface Interactions

1981 ◽  
Author(s):  
L H Edmunds
Keyword(s):  
Clinical Application ◽  
Heart Valves ◽  
Postoperative Bleeding ◽  
Left Ventricular ◽  
Ventricular Assist Devices ◽  
Factor Xii ◽  
Left Ventricular Assist Devices ◽  
Vascular Prostheses ◽  
Assist Devices

Blood contact with non-endothelial cell surfaces activates Factor XII and platelets. Clinical applications of temporary or permanent devices placed within or in series with the circulation are limited by this fact. Depending upon whether or not coagulation is inhibited, thrombosis or blood injury occur.In recent years improvements have been made in vascular prostheses, heart valves and assist devices. PTFE (Gortex) prostheses as small as 4 mm in diameter have been successfully used in selected high-flow applications such as aorto-pulmonary shunts. Improved mechanical heart valves have reduced the tendency of .valve thrombosis and possibly late emboli, but long-term anticoagulation is still required for patients with aortic bioprostheses and some patients with mitral xenografts. Development of durable relatively thromboresistant materials has led to wide and successful application of the intra-aortic balloon with few thromboembolic complications. Improved designs and development of durable, relatively thromboresistant materials have advanced experimental left ventricular assist devices to the stage of limited clinical application.When coagulation is inhibited by heparin, extracorporeal perfusion systems injure formed and unformed blood elements. Platelets particularly are activated with the result that platelet function is depressed and postoperative bleeding times are prolonged after perfusion with either membrane or bubble oxygenator systems. Currently clinical trials using prostacyclin to protect platelets during the period of bypass are underway. Bleeding consequences of platelet dysfunction and heparin continue to limit clinical application of long-term extracorporeal perfusion applications for cardiac and respiratory assistance.

The Role of Magnesium in Blood Coagulation

1967 ◽  
Vol 18 (03/04) ◽  
pp. 626-633 ◽  
Author(s):  
I Szelényi ◽  
J Rigô ◽  
B. O Ahmed ◽  
J Sos
Keyword(s):  
Blood Coagulation ◽  
Blood Platelets ◽  
Saturated Fat ◽  
Functional Importance ◽  
Long Term Experiments ◽  
Cellular Oxidation ◽  
The One ◽  
Physiological Type

SummaryHypercoagulative tendencies elicited by saturated fat could be repressed by oral or venous administration of magnesium in acute as well as in long term experiments.Magnesium appears to have double functional importance in coagulation : On the one hand, it exerts direct influence by antagonizing calcium, promoting fibrinolysis, and stabilizing fibrinogen and blood platelets and, on the other hand, it acts indirectly as well in that it causes vasodilatation and favours cellular oxidation.In the dynamic equilibrum of the processes taking part in blood coagulation magnesium appears to play its role as a physiological type of anticoagulant.

The Influence of Manufacturing Methods on the Function and Performance of a Synthetic Leaflet Heart Valve

1995 ◽  
Vol 209 (1) ◽  
pp. 65-69 ◽  
Author(s):  
M E Leat ◽  
J Fisher
Keyword(s):  
Heart Valve ◽  
Heart Valves ◽  
The Body ◽  
Ventricular Assist Devices ◽  
Ventricular Assist ◽  
Thermal Forming ◽  
Manufacturing Methods ◽  
And Performance ◽  
Hydrodynamic Function

There is considerable interest in polyurethane synthetic leaflet heart valves for both ventricular assist devices and direct implantation in the body. Two different manufacturing methods, thermal forming, and dip casting, of the leaflets have been investigated. There were only small differences in the hydrodynamic function of the valves made by the two methods. However, the durability of dip cast valves was far superior to the thermally formed film fabricated leaflets, with all of the dip cast valves reaching 160 million cycles without failure. This study indicates that a correctly designed and manufactured polyurethane synthetic leaflet heart valve has the potential for long-term implantation in the body.

scholarly journals Changes in the blood coagulation system that determine postoperative complications in patients with non-tumor mechanical jaundice

2021 ◽  
Vol 180 (2) ◽  
pp. 12-20
Author(s):  
V. E. Fedorov ◽  
B. S. Kharitonov ◽  
A. D. Aslanov ◽  
O. E. Logvina ◽  
M. S. Narizhnaya
Keyword(s):  
Postoperative Complications ◽  
Blood Coagulation ◽  
Blood Platelets ◽  
Coagulation Factors ◽  
Coagulation System ◽  
Thrombin Time ◽  
Blood Coagulation Factors ◽  
Blood Coagulation System ◽  
Normal Limits ◽  
Prothrombin Index

The OBJECTIVE was to study the features of changes in the blood coagulation system that contribute to the development of postoperative complications in patients depending on the stage of non-tumor mechanical jaundice at admission.METHODS AND MATERIALS. A total of 537 patients with mechanical jaundice were examined and changes in the blood coagulation system were analyzed. Vascular-platelet hemostasis was characterized by the following tests: capillary resistance, the number of desquamated endothelial cells, the number of blood platelets. Plasma hemostasis was analyzed using activated partial thromboplastin time, plasma soluble fibrin level, thrombin time, prothrombin ratio, prothrombin index, and fibrinogen blood level. Then, XIIa-dependent fibrinolysis in the blood and the level of the fibrin D-dimer in the blood plasma were determined.RESULTS. It was found that in the first stage of mechanical jaundice, with cholestasis, there were no changes in blood coagulation system that go beyond the normal limits. In the second stage, during cytolysis of hepatocytes, hyperbilirubinemia and hypertransaminasemia contribute to the activation of platelet first, and then plasma hemostasis. In the third stage (cholangitis), the death of endotheliocytes increases and there is a deficiency of blood coagulation factors due to their consumption and increased fibrinolysis.CONCLUSION. In the stage of cholestasis in patients with non-tumors mechanical jaundice, the parameters of the coagulation system remain within the reference values. In the stage of cytolysis, as endotheliotoxicosis increases, platelet and plasma hemostasis begins to activate, which can lead to thrombosis and thromboembolism in vital organs. In the stage of cholangitis, further activation of plasma hemostasis causes hemorrhagic syndrome. The occurrence of the described disorders in blood coagulation system with the progression of MJ dictates the need to monitor the changes in the blood coagulation system and their correction for the prevention of intra-and postoperative complications.

scholarly journals RELATIONSHIP BETWEEN PRE- AND POST-THROMBOSIS FACTORS IN PATIENTS WITH STAGE VD CKD TREATED BY LONG-TERM HEMODIALYSIS

2021 ◽  
Vol 74 (3) ◽  
pp. 471-474
Author(s):  
Oleksiy B. Storozhuk ◽  
Sergiy V. Shevchuk ◽  
Larysa O. Storozhuk ◽  
Tetyana V. Dovgalyuk ◽  
Borys G. Storozhuk
Keyword(s):  
Blood Coagulation ◽  
Coagulation System ◽  
Soluble Fibrin ◽  
Prophylactic Measures ◽  
Close Relationship ◽  
High Level ◽  
D Dimer ◽  
Significant Activation ◽  
Comprehensive Study

The aim: To determine informative value of pre-thrombosis, post-thrombosis and anticoagulation factors as well as their correlations for assessment of hemostasis status in patients with stage VD CKD. Materials and methods: Potential predictors of thrombophilia development as well as their relationships depending on the level of molecular markers of hemostasis were studied in 88 patients with stage VD CKD undergoing long-term hemodialysis with the view to determine their informative value. Results: Accumulation of soluble fibrin (sF) was demonstrated to cause moderate reaction of D-dimer (D-d) being insufficient in the absence of reaction of anticoagulant component of hemostasis. Soluble fibrin levels were found to be associated with D-d concentration (r = 0.39) and functionally inactive prothrombin forms (FIPF) to some extent (r = -0.24). Accumulation of FIPF in individuals with high level of sF implies significant activation of blood coagulation system at the stage prior to thrombin formation. Absence of close relationship between pre- and post-thrombosis indices may be indicative of still preserved potential of anticoagulant component of hemostasis. Conclusions: Accumulation of FIPF is an early marker of activation of blood coagulation and possible thrombosis. Levels of sF correlate with pre-thrombosis (fibrinogen, FIPF) and post-thrombosis (D-d) factors being associated with inhibition of anticoagulation processes. Comprehensive study of basic components of hemostasis in patients with VD stage of chronic kidney disease offer broader opportunities in arranging prophylactic measures to prevent thrombophilia.

Cardiovascular Medical Devices: Regulatory Science Research Overview in the Office of Science and Engineering Laboratories (OSEL) at the Food and Drug Administration (FDA)

2020 ◽  
Author(s):  
Kenneth Aycock ◽  
Ksenia Blinova ◽  
Maura Casciola ◽  
Brent Craven ◽  
Matthew Di Prima ◽  
...  
Keyword(s):  
Medical Devices ◽  
Heart Valves ◽  
Science Research ◽  
Test Methods ◽  
Ventricular Assist Devices ◽  
Clinical Test ◽  
Cardiovascular Research ◽  
Regulatory Review

Abstract The Cardiovascular Research Program in OSEL at the FDA consists of a diverse group of engineers and scientists who seek to drive innovation in cardiovascular device technology through development and standardization of pre-clinical test methods using in vitro, in vivo, and in silico models. The goal is to improve the pre- and post-market regulatory review processes and to accelerate patient access to safe and effective cardiovascular medical devices (e.g., heart valves, ventricular assist devices, cardiopulmonary bypass and cardiac mapping systems, ablation catheters, pacemakers, defibrillators, cardiac occluders, etc).

A Re-Appraisal of the Role of Blood Coagulation and Platelets in the Generalized Shwartzman Phenomenon

1966 ◽  
Vol 15 (03/04) ◽  
pp. 519-538 ◽  
Author(s):  
J Levin ◽  
E Beck
Keyword(s):  
Blood Coagulation ◽  
The State ◽  
Coagulation System ◽  
Renal Lesions ◽  
Intravascular Coagulation ◽  
Renal Glomeruli ◽  
Coagulation Mechanism ◽  
Shwartzman Phenomenon ◽  
Do So

SummaryThe role of intravascular coagulation in the production of the generalized Shwartzman phenomenon has been evaluated. The administration of endotoxin to animals prepared with Thorotrast results in activation of the coagulation mechanism with the resultant deposition of fibrinoid material in the renal glomeruli. Anticoagulation prevents alterations in the state of the coagulation system and inhibits development of the renal lesions. Platelets are not primarily involved. Platelet antiserum produces similar lesions in animals prepared with Thorotrast, but appears to do so in a manner which does not significantly involve intravascular coagulation.The production of adrenal cortical hemorrhage, comparable to that seen in the Waterhouse-Friderichsen syndrome, following the administration of endotoxin to animals that had previously received ACTH does not require intravascular coagulation and may not be a manifestation of the generalized Shwartzman phenomenon.

Changes in Blood Coagulation and Fibrinolysis in Rats Fed Atherogenic Diets

1963 ◽  
Vol 10 (02) ◽  
pp. 295-308 ◽  
Author(s):  
Clarence Merskey ◽  
Herbert Wohl
Keyword(s):  
Blood Coagulation ◽  
Blood Platelets ◽  
Coagulation Factors ◽  
Atherogenic Diet ◽  
Normal Serum ◽  
Significant Prolongation ◽  
Lysis Time ◽  
Factor Ii ◽  
Euglobulin Lysis Time ◽  
Coagulation And Fibrinolysis

Summary1. Groups of rats were fed thrombogenic diets and the effects on blood coagulation and fibrinolysis assessed.2. Animals fed a diet containing cholesterol, thiouracil and cholic acid developed high levels of coagulation factors I, II, V, VII—X, VIII, IX and X.3. Animals fed a similar diet with additional 40% beef fat developed even greater elevation of V, VII—X, VIII and X, similar elevation of factor II, and lesser (but still significant) elevation of factors I and IX. In addition marked elevation of blood platelets occurred.4. Euglobulin lysis time of the group not fed the additional fat was longer than in controls. Significant prolongation of euglobulin lysis time was not found in the group fed additional fat.5. If the increased levels of plasma fibrinogen were taken into account, it was found that a larger amount of fibrin was lysed per unit time in the euglobulin lysis test with plasma from rats fed either atherogenic diet compared with controls.6. Defective thromboplastin generation was present in both groups of rats fed an atherogenic diet. The defect was present in the serum and was not due to lack of a factor required for thromboplastin generation. An inhibitor was present in the serum which was capable of preventing the action of normal serum.7. No good correlation was found between the occurrence of changes in blood coagulation or fibrinolysis and the presence or absence of thrombosis and infarction.8. The exact cause of these anomalies remains unexplained, as does the cause of the thrombosis in these animals. Starvation per se does not account for these abnormal findings. They could not adequately be explained on the basis of “hypercoagulability” of the blood.

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