REVERSE REDISTRIBUTION - FACT OR FICTION

It has been well documented that it is not uncommon for a thallium-201 perfusion defect to develop or become more evident on delayed exercis e thallium scintigraphic imaging, as compared with the initial image i mmediately following stress. The pathophysiology and clinical signific ance of the phenomenon are currently unclear. Literature on this subje ct is reviewed, and it is concluded that reverse redistribution of (20 1)T1 in the post-myocardial infarction patient is indeed a ''fact''. I n this context it represents a low-risk condition and may imply succes sful thrombolysis, patent infarct-related coronary artery, improved wa ll motion at the infarct site and retained myocardial viability in tha t segment.