Case report of contrast transesophageal echocardiography to confirm extracorporeal membrane oxygenation (ECMO) catheter position in aortic dissection

: Extracorporeal cardiopulmonary resuscitation (ECPR) is the initiation of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) during resuscitation. As a clinical emergency, ECPR is often initiated with limited background information, especially for those with out of hospital cardiac arrest. The underlying cause of cardiac arrest is often revealed after the VA-ECMO is established. If the original culprit turns out to be aortic dissection, in which peripheral VA-ECMO is relatively contra-indicated, the first question to answer is whether the arterial return catheter is perfusing the true lumen. If not, the high retrograde flow to the false lumen can otherwise result in further progression of the aortic dissection. While aortogram by computer tomography is still considered one of the gold standards to confirm the catheter position, the transport risk for an unstable patient immediately after ECPR is still high. This article suggests a novel bedside method of using microbubble contrast transesophageal echocardiography, injected through the return cannula, to check if the blood flow is directed towards the true or the false lumen. The test result allows the clinicians prompt decision making on whether to change the VA-ECMO configuration or for early VA-ECMO withdrawal. The image of such a diagnostic contrast echocardiography technique is presented in this case report.