Case Author(s): V. Klaas , 12\16\94 . Rating: #D., #Q5

Diagnosis: MAA injection while on ECMO

Brief history:

39 year old female who underwent bilateral lung transplantation and repair of a VSD three days ago. She is now referred for evaluation of pulmonary perfusion (split function).


Anterior view of chest, after MAA injection (ECMO turned on)

View main image(pe) in a separate image viewer

View second image(pe). anterior view of chest. TC 99m MAA injected after ECMO was turned off.

Full history/Diagnosis is available below

Diagnosis: MAA injection while on ECMO

Full history:

39-year old woman who previously underwent bilateral pulmonary transplantation and repair of a ventriculoseptal defect. The patient is currently on extracorporeal membrane oxygenation (ECMO) and is referred for evaluation of pulmonary perfusion.


The initial image demonstrates uptake in the myocardium. The reason for this is that the patient was on ECMO during the injection of Tc-99m MAA. During ECMO blood is removed from the right atrium and sent through the ECMO chamber for oxygenation and then returned to the aortic root. Because of this, the Tc-99m MAA was also shunted directly from the right atrium to the aortic root with subsequent deposition in the myocardium. This problem was immediately recognized. Subsequently, the ECMO was turned off momentarily while a second dose of Tc-99m MAA was administered intravenously with resultant deposition in the pulmonary vascular bed as had been initially desired. Evaluation of pulmonary perfusion demonstrated asymmetry with the right lung receiving 94% and the left lung 6% of the total pulmonary perfusion.


The patient is currently under the care of the critical care team. Plans have been made for in-service training regarding ECMO for the nuclear medicine technical staff.

Major teaching point(s):

It is important when evaluating any patient who is on ECMO to understand the basics about ECMO and how it may effect the uptake of any radiopharmaceutical. In this case, the injection which was made while ECMO was operating resulted in significant uptake in the myocardium, with essentially no uptake in the pulmonary vascular bed. The injection made after ECMO was turned off resulted in deposition in the pulmonary bed, as was desired.

ACR Codes and Keywords:

References and General Discussion of Perfusion (only) Scintigraphy (Anatomic field:Lung, Mediastinum, and Pleura, Category:Normal, Technique, Congenital Anomaly)

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Case number: pe002

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