Carl-Erik Dempfle

Interleukin-1 beta promotes matrix metalloproteinase expression and cell proliferation in calcific aortic valve stenosis

Calcific aortic valve stenosis (AS), the main heart valve disease in the elderly, is characterized by extensive remodeling of the extracellular matrix. Matrix metalloproteinases (MMPs) are upregulated in calcific AS and might modulate matrix remodeling. The regulatory mechanisms are unclear. As recent studies have suggested that calcific AS might result from an inflammatory process involving leukocyte invasion and activation, the present study aimed to elucidate the role of the pro-inflammatory cytokine interleukin (IL)-1 beta on MMP expression and cell proliferation in human aortic valves. Immunohistochemistry for leukocytes, IL-1 beta and MMP-1 was performed on aortic valves with (n=6) and without (n=6) calcification obtained at valve replacement or autopsy. Stenotic valves showed marked leukocyte infiltration and associated expression of IL-1 beta and MMP-1. In control valves only scattered leukocytes, low staining for MMP-1 and no staining for IL-1 beta were present. Double-label immunostaining localized IL-1 beta expression mainly to leukocytes and MMP-1 expression to myofibroblasts. Stimulation of cultured human aortic valve myofibroblasts with IL-1 beta lead to a time-dependently increased expression of MMP-1 and MMP-2 by Western blotting and zymography, whereas MMP-9 remained unchanged. Cell proliferation was increased by IL-1 beta as determined by bromodesoxyuridine incorporation. Thus, IL-1 beta may regulate remodeling of the extracellular matrix in calcific AS.

Randomized controlled study of heparin and low molecular weight heparin for prevention of deep-vein thrombosis in medical patients.

166 patients aged 40-80 years were included in a controlled, randomized, double-blind study to determine the efficacy and safety of a single daily injection of a low molecular weight (LMW) heparin for prevention of deep-vein thrombosis compared to low dose conventional heparin. Patients received 1 x 1.500 aPTT units of a LMW heparin fraction (plus 2 x placebo injection) or 3 x 5.000 IU of an unfractionated heparin. During 10 days of treatment, patients underwent repeated clinical investigation, serial impedance plethysmography, and Doppler sonography for detection of thrombosis of the lower limbs. Combined application of these methods revealed evidence of thrombosis in 4.5% of patients on unfractionated heparin and 3.6% of patients on LMW heparin. Subcutaneous hematomas were significantly smaller in diameter upon treatment with LMW heparin (p less than 0.001). Antithrombin III levels were significantly higher at the end of the observation period in the LMW heparin group (p less than 0.005). Thrombocyte count, transaminases, creatinine, and haemoglobin did not change in either group. The results indicate that LMW heparin administered by a single s.c. dose daily may be as effective as low dose heparin in prevention of deep venous thrombosis in medical inpatients.

Use of soluble fibrin antigen instead of D-dimer as fibrin-related marker may enhance the prognostic power of the ISTH overt DIC score

The overt DIC score of the DIC subcommittee of the ISTH includes a fibrin-related marker (FRM) as indicator of intravascular fibrin formation. The type of marker to be used has not been specified, but D-dimer antigen, or fibrin degradation products are used by most investigators. Soluble fibrin complexes have been suggested as more specific indicators of acute intravascular fibrin formation. The aim of the present study was to compare the predictive value of the overt DIC score concerning clinical outcome in a surgical intensive care cohort, using either D-dimer antigen, or soluble fibrin antigen as FRM. The cutoff values for 2 and 3 score points for the FRM were assigned on the basis of the 25% and 75% quartiles of 1870 plasma samples obtained from 359 ICU patients during a period of 6 months. For 331 patients with complete diagnostic workup and day 1 blood samples, the Iatro SF as FRM component of the overt DIC score displayed the highest prognostic power concerning clinical outcome. The 28-day mortality of patients with overt DIC at day 1, using Iatro SF as FRM assay was 50.0%, whereas 28-day mortality of patients without overt DIC was 14.0% (p <0.0001). Using MDA D-dimer, and TINAquant D-dimer, 28-day mortality was between 35.5% and 39.3% in patients with overt DIC, and 15.5% to 15.6% in patients without overt DIC. Selection of the FRM as component of the DIC score has a small, but relevant impact on the prognostic performance of the overt DIC score. The present data on the distribution of values may provide a basis for the selection of appropriate cutoff points for assigning 2, and 3 points in the score.

Valproate-associated Coagulopathies Are Frequent and Variable in Children

Summary:  Purpose: Valproic acid (VPA) is an antiepileptic drug (AED) commonly used for generalized and focal epilepsies. The clinical relevance of coagulopathies, known as side effects of VPA therapy, especially thrombocytopenia, von Willebrand disease, and a decrease of factor XIII, is still unclear.

Coagulopathy of sepsis

Disseminated intravascular coagulation (DIC) is a common phenomenon in patients with sepsis, but the clinical implications of this condition are not clear. Clinical trials with coagulation inhibitors have failed to show a significant benefit concerning survival. DIC is primarily a laboratory diagnosis, based on the combination of elevated fibrin-related markers (FRM), with decreased procoagulant factors and platelets. Non-overt DIC is observed in most patients with sepsis, whereas overt DIC is less frequent. Patients with overt DIC may display consumption coagulopathy and purpura fulminans. Consumption coagulopathy is a bleeding disorder caused by low levels of platelets and procoagulant factors associated with massive coagulation activation. Purpura fulminans is caused by widespread microvascular thrombosis, resulting in tissue necrosis. Treatment with drotrecogin alfa (activated) improves survival and other outcome parameters in severe sepsis, including a subgroup of patients fulfilling the laboratory criteria of overt DIC. No randomized trials demonstrating effective therapies in consumption coagulopathy have been published. Bleeding patients with consumption coagulopathy are most frequently treated with platelet transfusions and various plasma products including fresh frozen plasma and coagulation factor concentrates. Based on case reports, treatment with drotrecogin alfa (activated) or substitution of protein C have been recommended for adjuvant treatment of sepsis-related purpura fulminans.

Changes in Coagulation and Fibrinolysis Markers in Acute Ischemic Stroke Treated With Recombinant Tissue Plasminogen Activator

BACKGROUND AND PURPOSE Shifts of the balance between coagulation and fibrinolysis play a crucial role in pathogenesis and treatment of cerebral ischemia. In this study, we characterized the kinetics of hemostatic abnormalities induced by acute ischemic stroke and its thrombolytic (recombinant tissue plasminogen activator [rtPA]) or anticoagulant (heparin) treatment. METHODS Systemic generation of molecular markers of hemostasis (fibrin monomer, D-dimer, thrombin-antithrombin complex, and fibrinopeptide 1.2) was monitored in acute ischemic stroke, and the effects of thrombolytic and anticoagulant treatments were analyzed. RESULTS Thrombolysis with rtPA induced a massive response of markers of coagulation activation and fibrin formation that peaked after 1 to 3 hours and persisted for up to 72 hours. In contrast, only minor hemostatic changes were induced by acute ischemic stroke itself. Administration of heparin did not significantly affect these hemostatic abnormalities. CONCLUSIONS This first characterization of the coagulation activation induced by rtPA treatment for acute ischemic stroke and the failure to abolish such hemostatic abnormalities by heparin may be of value for further refinement of the currently discussed thrombolytic therapy and the controversial adjunctive anticoagulant prophylaxis in stroke patients.

Time-dependent changes in the plasma concentration of matrix metalloproteinase 9 after acute myocardial infarction

Matrix metalloproteinase (MMP)-2 and MMP-9 are believed to play a pathophysiologic role in acute myocardial infarction (MI). The time course of their plasma concentrations in correlation with the extent of myocardial damage is unclear. In a prospective study, 20 patients with proven acute MI underwent successful reperfusion within 6 h after the onset of symptoms. The patients were divided into two groups according to the size of their MI, i.e. large or moderate MI. Plasma concentrations of MMP-2, MMP-9 and tissue inhibitor of metalloproteinase (TIMP)-1 were determined on admission, and after 24 h, 48 h, 1 week, 4 weeks, 3 months and 6 months. MMP-2 levels remained unchanged over time in both groups. The plasma concentration of MMP-9 was elevated on admission in patients with large MI versus moderate MI (195 ± 190 versus 78 ± 63 ng/ml, p < 0.01) as determined by left ventriculography, and returned to baseline (18 ± 16 ng/ml) by 1 week after MI. TIMP-1 levels rose slowly in patients with large MI and returned to baseline at 6 months. The ratio of MMP-9 to TIMP-1 was significantly increased on admission in both groups and returned to baseline at 48 h. These data suggest that MMP-9 might play a pathophysiologic role during the early phase of acute MI.

[Prevention, diagnosis, treatment, and follow-up care of sepsis. First revision of the S2k Guidelines of the German Sepsis Society (DSG) and the German Interdisciplinary Association for Intensive and Emergency Care Medicine (DIVI)].

(Orientiert an der Definition der Agency for Health Care Policy and Research fur die „Clinical Practice Guidelines“ der USA): „Leitlinien sind systematisch entwickelte Darstellungen und Empfehlungen mit dem Zweck, Arzte und Patienten bei der Entscheidung uber angemessene Masnahmen der Krankenversorgung (Pravention, Diagnostik, Therapie und Nachsorge) unter spezifischen medizinischen Umstanden zu unterstutzen.“ Leitlinien geben den Stand des Wissens (Ergebnisse von kontrollierten klinischen Studien und Wissen von Experten) uber effektive und angemessene Krankenversorgung zum Zeitpunkt der „Drucklegung“ wieder. In Anbetracht der unausbleiblichen Fortschritte wissenschaftlicher Erkenntnisse und der Technik mussen periodische Uberarbeitungen, Erneuerungen und Korrekturen unternommen werden. Die Empfehlungen der Leitlinien konnen nicht unter allen Umstanden angemessen genutzt werden. Die Entscheidung daruber, ob einer bestimmten Empfehlung gefolgt werden soll, muss vom Arzt unter Berucksichtigung der beim individuellen Patienten vorliegenden Gegebenheiten und der verfugbaren Ressourcen getroffen werden.

Point of care coagulation tests in critically ill patients.

Point of care assays for various analytes have been established in critical care, including blood gas analysis, glucose, electrolytes, and markers for cardiac ischemia. Coagulation assays can also be adapted to the critical care environment by using whole blood as sample material and instruments optimized for point of care analysis. Available assays include the conventional coagulation assays, such as prothrombin time and activated partial thromboplastin time, fibrinogen, assays for monitoring of anticoagulant drugs, global coagulation assays based on thrombelastography and viscosimetry, platelet function assays, and D-dimer assays. The main problem in point of care coagulation diagnostics is quality control. Point of care coagulation assays help in rapidly establishing a diagnosis, clarifying causes of bleeding, and monitoring therapy. Thrombelastography and similar assays extend the scope of coagulation diagnostics by visualizing the process of clot formation and extending the observation period to provide an estimate of clot stability versus mechanical and proteolytic attack.

High incidence of vaproate-induced coagulation disorders in children receiving valproic acid: a prospective study.

Reports have been published on blood coagulation disturbances by valproate therapy. In the present prospective trial, blood samples were drawn before valproate therapy, after 6 weeks of therapy, after more than 6 weeks and after longer than 6 months of valproate therapy from 23 children newly treated with valproate. Two children developed thrombocytopenia, and six children with initial normal von Willebrand factor showed acquired von Willebrands disease. Fibrinogen levels dropped below the lower limit in 12 patients and subnormal factor XIII plasma levels were observed in 17% of patients. No patient developed signs of hemorrhage. Eight percent of patients developed valproate-induced thrombocytopenia. Reduction in platelets did not reach statistic significance. Thrombelastography showed a 47% incidence of altered platelet function. We found a statistically significant, positive correlation between clotting time of collagen extrinsic pathway inhibitor and, accordingly, adenosindiphosphate and valproate level. Plasmatic coagulation investigations showed a significant decrease of prothrombin time. Activated partial thromboplastin time measurements also showed significant prolongation with valproate. Activity of von Willebrand factor antigen and von Willebrand factor ristocetin cofactor significantly decreased. Factor XIII activity significantly decreased after valproate therapy for longer than 6 months (17% of children). Fibrinogen was significantly reduced. In the coagulatory system a decrease in the main antiprotease antithrombin III activity was observed. Blood coagulation disturbances are common in patients with valproate, but rarely become clinically symptomatic. Acquired von Willebrands disease and hypofibrinogenemia may become relevant in patients with surgery or trauma. Particular attention should be paid to factor-XIII deficiency, which is especially seen with valproate therapy.