We have developed an advanced tissue processing technique on porcine pulmonary heart valves for pulmonary valve replacement and its initial clinical application during the autograft operation according to Ross. The novel concept consists of a cell-free matrix achieved by deoxycholic acid treatment that is repopulated by host cells in vivo. Molecular biology, radioligand binding, and electron microscopy consistently showed that these valves are almost free of cellular components. Animal experiments and clinical investigations revealed excellent hemodynamic properties of the valves, no need for antithrombotic therapy, and repopulation by host cells without any signs of calcification. In juvenile sheep the internal diameter of the implanted valves significantly increased in growing animals by approximately 10 mm. The repopulation of the decellularized heart valves was found not only in sheep but also in humans, which indicates that the underlying mechanisms, presumably repair mechanisms, might be common in mammals. If these findings can be confirmed by others, they will lead to new concepts in the field of cardiovascular tissue engineering that will eliminate the need for in vitro construction of autologous heart valves.

it is possible to conduct apheresis at the following 2 days after acute myocardial infarction in a porcine infarction model and to analyze the infarct by cardiovascular magnetic resonance imaging at day 1 and 14. Copyright © 2010 S. Karger AG, Basel C-reactive protein (CRP), a classical acute phase protein, has been extensively studied as a systemic marker of inflammatory processes. During acute myocardial infarction (AMI), the circulating CRP concentration increases and its level predicts the outcome of AMI [1][2][3] . However, there is still a controversy whether CRP is only a marker or a risk factor, contributing causative to myocardial damage after AMI.In rats, administration of human CRP after ligation of the coronary artery reproducibly enhanced infarct size by up to 40% [4,5] . They received 40 mg/kg of isolated pure human CRP by intraperitoneal injection 1 h after coro- Key WordsAcute myocardial infarction ؒ Acute phase protein ؒ Adsorber ؒ Apheresis ؒ C-reactive protein Abstract Background: C-reactive protein (CRP) is a possible causative factor of the destructive processes observed during the weeks after myocardial infarction. Methods: We developed a clinically relevant animal model including the removal of CRP from blood plasma utilizing a specific CRP adsorber and the visualization of the infarct scar in the living animal by cardiovascular magnetic resonance imaging as a tool to investigate the impact of CRP after acute myocardial infarction. Results: We describe the facets of this model system and kinetics of clinical blood parameters like CRP and troponin. In addition, we demonstrate the potency of CRP apheresis reducing CRP levels by ϳ 70% in the established treatment system. Conclusion: We showed for the first time that

Optimizing volume load is effective for minimizing hemodynamic changes during CP in the head-up and in head-down positions. In general, beta(1)-blockers cannot be recommended because they might additionally compromise myocardial contractility and suppress compensatory reaction of the sympathetic nerve system. Vasodilation has not improved hemodynamic parameters during CP.

A model of hemoperfused slaughterhouse pighearts is described providing a wide range of applications which leads to a reduction in animal experiments. The size of a pigheart, heart rate, coronary perfusion, metabolism, etc. are more comparable to conditions in patients than those in hearts of small laboratory animals. Global heart function can be assessed either by measuring stroke volume, ejection fraction, Emax etc. in the working model or by measuring intraventricular pressure with balloon catheters in the isovolumetric model. Regional cardiac function can be measured by sonomicrometry and ischemic and non-ischemic areas can be compared. Local metabolic changes are measurable as well with microdialysis. Cardiac function can be kept on any given functional level by infusion of norepinephrine in spite of the fact that functional parameters are lower without adrenergic drive in vitro than in vivo. Stable heart function can be maintained for several hours with only 500 to 1000 ml of blood because the blood is permanently regenerated by a special dialysis system. This model can be applied in many research projects dealing with reperfusion injuries, inotropic, antiarrhythmic or arrhythmogenic effects of certain drugs, immunological rejection, evaluation of imaging systems (NMR, echocardiography etc.) or cardiac assist devices.

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