MARKERS OF THROMBOTIC RISK FUTURE DIRECTIONS IN THERAPEUTICS

摘要

The risk for developing Thrombotic or thromboembolic events (TTE) is dependent upon many things but can classified under the three arms of Virchow's triad which include vascular stasis, endothelial injury, and hypercoagulability. While dramatic abnormalities in any of these arms can result in clinical thrombosis, a more practical approach would be to consider the cumulative thrombotic risk where each arm adds or reduces the risk for the development of thrombosis. However, while blood stasis and endothelial injury appear to be most related to an underlying disease condition which can occur in any individual within a population and quantified in terms of degree of severity, the hypercoagulability arm may be more of a specific characteristic of an individual. In fact, there may be a population of individuals that exhibit a particular characteristic that confers hypercoagulability although the degree of this hypercoagulability may be quite variable from one individual to the next. The variability in the hypercoagulable arm most likely results in the wide spectrum of TTE within a disease population. A pertinent example would be why some cats with extremely dilated atria with myocardial disease do not develop cardioembolic events (CE) while cats with much smaller atria experience such events. This has resulted in the mixed data from the literature where some studies conclude that left atrial size is a risk factor or CE while others do not see this relationship. Accurate prediction of hypercoagulable states would have a dramatic impact on patient prognosis and therapeutic interventions where a more accurate risk-to-benefit ratio could be determined. This would allow clinicians to decide if the possible bleeding risk from an antithrombotic agent is outweighed by the benefit of preventing a TTE. Unfortunately, these studies are currently lacking in veterinary medicine.