Beyond the clot: long-term management of cats with aortic thromboembolism

Abstract

Aortic thromboembolism (ATE) is an all too common and potentially devastating sequela of feline cardiomyopathy. Cats with hypertrophic cardiomyopathy, restrictive cardiomyopathy, and cardiac disease induced by chronic, uncontrolled hyperthyroidism are the most frequent victims of ATE. Some sources estimate that between 25% and 33% of cats with cardiomyopathy will develop ATE at some point in their disease process. As we become more skilled at nursing these patients through their acute thromboembolic crisis, the survival rate has increased from the previously reported percentage of less than 30%. The new "crisis" is the recurrence rate of ATE, which some studies estimate to be as high as 75%. Our new focus must be the long-term management of cats that have been diagnosed with a previous episode of ATE in hopes of prevention of recurrence and/or a decrease in the severity of the disease process should there be another incident. Medical therapy has focused on the use of anticoagulants (e.g. warfarin and heparin) and low-dose aspirin regimens, but new drugs that directly inhibit platelet agonists and different platelet receptors (e.g. clopidogrel and abciximab) may prove to be more effective. Prospective studies focusing on new drugs and on alternate ways of detecting the patient that is prone to ATE are needed.