FREDERICK ADOLPH REICHLE
Medical Practice in Warrington, PA

2003006, Apr 10, 2003

Sep 23, 2002

10/253231

Frederick Herz - Warrington PA, US
Frederick Reichle - Warrington PA, US

A61H009/00

601/152000

Deep venous thombosis with the attendant risk of pulmonary embolism and post phlebitic syndrome is a frequent complication in older patients who have undergone surgery, suffered trauma or who have serious illness such as malignancy or sepsis. In any category patients who are 40 years of age or older are considered to be at greatest risk. Deep vein thrombi vary from a few millimeters in length to long tubular masses that partially or completely fill the deep main veins of the leg. These thrombi start as small nidi and initially grow in size by deposition of successive red and white layers. The white layers are rich in platelets and neutrophils interspersed with fibrin while the red layers contain most erythrocytes entrapped in fibrin (Hume et al, p. 26-30). Beyond a certain stage of growth venous thrombi become mostly red, resembling clotted blood, i.e., the bulk of a clinically significant thrombus is composed mostly of erythrocytes entrapped in fibrin. Thus, platelets, neutrophils and especially blood coagulation all contribute to formation of thrombi in deep leg veins. Both initiation and propagation of thrombi depend on processes that are necessary for defense of the body against trauma and infection. Platelet activation (and accumulation) and blood coagulation are necessary to stop the loss of blood from disrupted blood vessels. Neutrophil response to stimulation is essential for defense of the body against infection. Thus, initiation and propagation of DVT might be considered to represent an undesirably large response of normal defense mechanisms in the deep veins of the leg. Approaches to preventing DVT must be based on a realization that neither of these processes can be completely inhibited throughout the body for more than a brief time without serious risk of bleeding or infection. Thus it is obviously desirable to inhibit thrombotic processes locally rather than systemically. To do this it will be necessary to obtain higher levels of antithrombotic drugs in the deep veins of the legs than in the systemic circulation. The present patent application proposes devices and methods that will make this possible for the first time. The claims can be considered in two categories. The first is devices necessary to achieve such delivery. The second is a method for delivery of a high level of antithrombotic drugs.