Cardiology MCQ: Catheter thrombosis with Fondaparinux

Catheter thrombosis with Fondaparinux is due to: a) High anti-Factor Xa activity b) Low anti-Factor IIa activity c) High factor VIIIa activity d) Low factor Xa activity Correct answer: b) Low anti-Factor IIa activity Though Fondaparinux is a safe and effective in the management of ST elevation myocardial infarction, it was associated with a higher incidence of guide catheter thrombosis in those who underwent percutaneous coronary intervention. The same concern applies to non ST elevation acute coronary syndromes where fondaparinux is ideal in terms of lower bleeding risk, albeit with a potential risk of guide catheter thrombosis in case they need percutaneous coronary intervention [Mehta SR et al. Efficacy and safety of fondaparinux versus enoxaparin in patients with acute coronary syndromes undergoing percutaneous coronary intervention: results from the OASIS-5 trial. J Am Coll Cardiol 2007;50(18):1742-1751]. This is because of low anti-Factor IIa activity. Fondaparinux has relatively pure anti-Factor Xa activity. Unfractionated heparin has the best anti-Factor IIa activity. Hence it is possible to reduce the chance of guide catheter thrombosis in those treated with fondaparinux by supplementing unfractionated heparin. In vitro studies by Yau JW et al [Mechanism of catheter thrombosis: comparison of the antithrombotic activities of fondaparinux, enoxaparin, and heparin in vitro and in vivo. Blood. 2011;118:6667-74] showed that catheters are thrombogenic because they activat...
Source: Cardiophile MD - Category: Cardiology Authors: Tags: Angiography and Interventions Cardiology MCQ Coronary Interventions DM / DNB Cardiology Entrance Source Type: blogs