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H Hartert

Publications and source records attributed to H Hartert.

10 recordsLinked to original sources
PubMed1990

Orbitometer flow and thrombus formation.

Orbitometry (Hartert) is a rheological ex-vivo method to follow up physical assembly of a coagulum in layers during natural intensity of flow by orbital movement. Fibrin elasticity in the Orbitometers mode of Resonance Thrombography is differentiated from platelet activity as well as e.g. from the effects of disseminated coagulation-minimal in liver disease and maximal during disturbances of delivery. Transition into the mode of dynamic Tendography (Hartert) will e.g. register all fast going tests lasting minutes or seconds. It is comparable to an accelerated form of Thrombelastography (Hartert), the intercourse of which with coagulum yet is an exclusively static operation. Another category is measurement of blood and plasma viscosity. In concentrated blood it seizes plasticity of blood cells as well as their intensity of aggregation in orbital flow. The latest methodical development of Orbitometry is control of platelet activity in its function of adhesion. This is realized by measurement of specific physical effects released in platelet containing coagulum. They generate a structural degradation of fibrin elasticity modul as well as a tendency for coagulum adhesion. The practical use of Adhesiography is control of anticoagulants and platelet protecting substances in their quantitative influence on coagulum structure and on the mentioned platelet activities. A special disturbance of these platelet depending mechnisms obviously is getting evidence in case of v. Willebrand's syndrome.

Blood Coagulation Disorders↗
PubMed1988

Fibrin elasticity and coagulation.

Sudden increase of viscosity in former times indicated the start of coagulation. Yet its measurement destroyed the structure of coagulum. By the precursor method of thrombelastography the author 1944 found elasticity to be the essential physiological property of coagulum. In the production of elastic fibrin structure its early phase is the most efficient in this respect. The speed of prime structure formation is extremely fast in presence of enough phospholipid as well as of plasma factor XIII. Even high amounts of thrombin cannot replace one or both of these substances indispensable to grow rapidly a perfect fibrin web. This phase yet does not become effective if it is not accompanied by the orbital micro-flow of the new orbitometry method. Its shear is comparable to that in a coronary artery. The special resonance effect of the method in combination with the early phase of fibrin production is generating some kind of a physiological feed back: increasing fibrin will strengthen shear stress as long as less platelets are entangled which will reduce the elastic flexibility of fibrin web. Some kind of a "coagulation spin effect" in optimal combination of shear stress, phospholipid and factorXIII, will extremely fast originate a firm fibrin structure, a mechanism which may be of significance for a fast occlusion of arterial stenoses.

Blood Coagulation↗
PubMed1984

Resonance thrombography.

Resonance Thrombography is a method to follow up the coagulation process ex vivo from its very beginning up to its final consolidation phase resp. fibrinolysis. The mode of measurement is adopting the resonance effect of fibrin elasticity. The connection of a cylindric rod and outer cylinder by elastic fibrin fibres will increase the potential natural frequency (38 Hz) of the elastically suspended rod, to which a constant orbital drive of a very small radius is imported electronically. Change of difference between constant drive frequency and varying resonance frequency over time will result in sensitive registration of the Resonance Thrombogram (RTG). The orbital movement of the rod causes a circular flow of blood as long as it is fluid. The speed of flow is comparable to that in a medium sized vein, resembling a physiological situation. The clinical application of RTGraphy is regarding the fact, that there is practically no disturbance of clotting process which is not represented in any change of clot construction. Diagnosis of DIC, demonstration of SFMC as well as of fibrinolysis, differentiation between the effect of fibrin structure and of platelet activity are among the clinical assignments of RTGraphy.

Adult↗
PubMed1981

[Clinical problems of microrheology in disseminated intravascular coagulation (author's transl)].

Among the earliest products of a potentially succeeding disseminated intravascular coagulation (DIC) are the soluble fibrin monomer complexes representing a state of hypercoagulability. They are passing microcirculation as long as there are no precipitation activities, which may involve only one single organ. A typical example is the endotoxin shock followed by fibrination of the kidneys. The clogging of microcirculation by fibrination specifically released in this organ or another may be prevented in case of a well-timed diagnosis, but scarcely can be removed therapeutically (possibly therapeutical fibrinolysis). The effects of localising fibrination yet independent of clotting mechanism may be tackled by treating the causal disease. Hypercoagulability always preceding DIC can be controlled mainly by heparin. Its well-timed application depends on diagnostics which are able to define the momentary situation in the mostly progredient process, comprising a mortality of about 50%. Finally, as a possible method to assess the clinical situation the resonance thrombography, a successor of thrombelastography, is put forward.

Blood Coagulation Disorders↗