Transient ischaemic dilatation

Transient ischaemic dilatation is a paradoxical phenomenon seen in myocardial perfusion SPECT imaging.  

With severe balanced coronary artery disease, myocardial ischaemia may result in apparent enlargement of the left ventricular cavity during stress. The cause of this is not entirely clear, but some speculate that it may be (at least partly) due to extensive subendocardial ischaemia.

The TID ratio is the stress volume : rest volume. Abnormally elevated TID ratio has been defined with abnormal cutoff values ranging from 1.12-1.22.2

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Article information

rID: 31807
System: Cardiac
Section: Signs
Synonyms or Alternate Spellings:
  • TID
  • Transient ischemic dilatation

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