Arterial grafts material development

There are three absolute contraindications to the initiation of thrombolytic therapy (1) active uncontrollable hemorrhage, (2) likely persistent proximal source of embolization, or (3) neurovascular compromise in the affected extremity, where it is likely that a reperfusion injury such as myonecrosis may develop. Relative contraindications include recent intra-abdominal or intrathoracic surgery, uncontrollable hypertension, a recent intracerebral event that is likely to be hemorrhagic, and possibly the recent use of a porous intra-arterial graft material. Thrombolytic complications are proportional to the duration of therapy and usually consist of hemorrhage, often related to concomitant need for anticoagulation. 

A broad-based cardiomyoplasty market should emerge by the late 1990s. Successhil development of a small-diameter graft to use in coronary bypass surgery instead of the patient s saphenous vein or mammary artery seems likely to occur by the year 2000. Development of appropriate materials and manufacturing methods are needed to maintain patency without damaging blood in grafts below 4 mm in diameter. 

In this context, the development of novel biocompatible materials becomes more and more important Current grafts are restricted to large and medium diameters since none of the available ones is suited for the replacement of small-diameter vessels or coronary arteries, respectively. 

We have also provided evidence that the behavior of microorganisms in confined micro-environment is substantially different and that their desired metabolic activities can be maximized through the modification of the surface characteristics as well as the size of the pores. These characteristics can therefore be utilized in BI as well as in the enhancement of cell penetration and cell proliferation in tissue engineering and when such polymers are grafted. Micro-fabrication technique has also been used in the development of highly porous catalysts with arterial channels feeding nano-pores which provide an extended surface area. Such materials can be used as micro-reactors as well as catalysts. 

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