Bivalirudin and post-cardiotomy ECMO: a word of caution.

Bivalirudin has been proposed as the sole anticoagulant in patients under extracorporeal membrane oxygenation (ECMO) or cardiopulmonary bypass. Owing to the pharmacodynamic properties of bivalirudin, areas of blood stagnation should be carefully avoided in order to limit the risk of thrombosis. The ECMO circuit has no reservoir and is usually devoid of blood stagnation areas. Conversely, under some circumstances, intracardiac blood stagnation areas may exist. In this case, there is a potential risk for the spontaneous formation of an intracardiac thrombus. We suggest that, under bivalirudin anticoagulation, a minimal degree of intracardiac blood flow with left heart valve movement is allowed.