Thromboembolic potential

The synthetic polymeric components as well as their combinations with proteins such as human serum albumin (HSA), bovine serum albumin (BSA), human serum albumin/a-interferon mixtures (HSA-IFNa) and myoglobin (MYO) did not give any negative response to in vitro and in vivo biocompatibility tests, such as platelet aggregation, complement activation, acute toxicity, and acute thromboembolic potential. 

Based on the hemolysis and TEC data and other pertinent information in the literature, we have been able to draw certain conclusions about the hemolytic and thromboembolic potential of the different valve designs. The locations of thrombus formation, excess tissue growth and related valve dysfunctions will be discussed in the text. 

The daily dose of sulfinpyrazone is 200-400 mg. The side effects of sulfinpyrazone are comparable with those of probenecid. A potential therapeutic advantage of sulfinpyrazone in patients with coronary heart disease and thromboembolic diseases is its inhibitory effect on platelet aggregation. 

The role of the platelet integrin GPIIb/IIIa receptor and its potential utility as a radio-diagnostic agent in the rapid detection of thromboembolic events has been demonstrated [6]. This approach may be useful for the noninvasive diagnosis of various thromboembolic disorders. 

Given that VTE is often clinically silent and potentially fatal, prevention strategies have the greatest potential to improve patient outcomes.2 To rely on the early diagnosis and treatment of VTE is unacceptable because many patients will die before treatment can be initiated. Furthermore, even clinically silent disease is associated with long-term morbidity from the postthrombotic syndrome and predisposes the patient to future thromboembolic events. Despite an immense body of literature that overwhelmingly supports the widespread use of... 

A case report with a review of 27 cases of thromboembolic events after the administration of intravenous globulin with or without glucocorticoids has been published (492). The authors suggested that this combined therapy should be administered with caution because of its potential synergistic thrombotic risk. 

One of the most serious aspects of the thromboembolic complications now widely acknowledged as being associated with HRT is that their emergence coincides with the development of the conclusion that the role of HRT in reducing the risk of coronary heart disease is at best unproven. A form of treatment that was originally viewed as potentially beneficial to the cardiovascular system is at present on balance perhaps harmful (33). 

There is other evidence that transdermal estrogen replacement therapy has relatively little effect on hemostasis. In a case control study, 155 consecutive patients with a first documented episode of idiopathic venous thromboembolism, 92 of whom had had a pulmonary embolism and 63 a deep venous thrombosis, were compared with 381 healthy matched controls (88). Overall, 32 (21%) of the cases and 27 (7%) of the controls were current users of oral estrogen replacement therapy, whereas 30 (19%) cases and 93 (24%) controls were current users of transdermal estrogen replacement therapy. After adjustment for potential confounding variables, the odds ratios for venous thromboembolism in current users of oral and transdermal estrogen replacement therapy compared with non-users were 3.5 (95% Cl = 1.8, 6.8) and 0.9 (0.5, 1.6) respectively. Estimated risk for venous thromboembolism in current users of oral estrogen replacement therapy compared with transdermal users was 4.0 (1.9, 8.3). 

In a case-control study 155 postmenopausal women who had had venous thromboembolism were compared with 381 matched controls (91). In all, 32 cases and 27 controls were current users of oral replacement therapy, whereas 30 cases and 93 controls were current users of transdermal products. After adjustment for potential confounding variables, the estimated risk ratio for venous thromboembolism in current users of the oral products compared with the transdermal users was 4.0 (1.9-8.3). This is strong evidence that the transdermal route was considerably safer. However, the conclusions of different studies continue to conflict with one another, no doubt in part because of variations in the formulations and patterns of use of the products. 

Eriksson Bl, Dahl OE. Prevention of venous thromboembolism following orthopaedic surgery clinical potential of direct thrombin inhibitors. Drugs 2004 64 577-595. 

Agnelli G, Clinical potential of oral direct thrombin inhibitors in the prevention and treatment of venous thromboembolism. Drugs 2004 64(suppl I ) 47—52. 

Schuler OG, Eriskat J, Baethmann AJ, Back T (2001a) Thrombolysis induces a reperfusion-dependent inhibition of peri-infarct depolarizations in experimental thromboembolic stroke. J Cereb Blood Flow Metab 21 S396 Schuler OG, Plesnila N, Otto D, Baethmann AJ, Back T (2001b) Early thrombolysis inhibits periinfarct depolarizations in embolic MCA occlusion. NeuroReport 12 3943-3946 Schwindt W, Burke M, Pillekamp F, Luhmann HJ, Hoehn M (2004) Functional magnetic resonance imaging and somatosensory evoked potentials in rats with a neonatally induced freeze lesion of the somatosensory cortex. J Cereb Blood FlowMetab 24 1409-1418... 

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