Myocardial perfusion and viability

Last revised by Yuranga Weerakkody on 12 Jun 2023

Citation, DOI, disclosures and article data

Citation:

Goel A, Weerakkody Y, Mellam Y, et al. Myocardial perfusion and viability. Reference article, Radiopaedia.org (Accessed on 23 Apr 2024) https://doi.org/10.53347/rID-37070

DOI:

https://doi.org/10.53347/rID-37070

Permalink:

https://radiopaedia.org/articles/37070

rID:

37070

Article created:

24 May 2015, Ayush Goel ◉

Disclosures:

At the time the article was created Ayush Goel had no recorded disclosures.

View Ayush Goel's current disclosures

Last revised:

12 Jun 2023, Yuranga Weerakkody ◉

Disclosures:

At the time the article was last revised Yuranga Weerakkody had no financial relationships to ineligible companies to disclose.

View Yuranga Weerakkody's current disclosures

Revisions:

11 times, by 10 contributors - see full revision history and disclosures

Systems:

Cardiac

Tags:

refs, cases

Synonyms:

Cardiac perfusion

Myocardial perfusion and viability assessment is important for many reasons:

to diagnose, locate and grade the severity of coronary artery disease
to identify candidates who would benefit from revascularisation
to evaluate response to revascularisation

Terminology

Stunned myocardium

Stunned myocardium refers to a state in which there is wall dysfunction but the perfusion (resting and stress) is normal; (see the main article on stunned myocardium for more details).

Myocardial ischaemia

Myocardial ischaemia refers to a state in which there is decreased perfusion of the myocardium when stressed (such as during exertion) but normal perfusion during rest (seen as reversible perfusion defect). These patients will significantly benefit from treatment.

Hibernating myocardium

With hibernating myocardium, the myocardium shows decreased perfusion on both stress and resting phase (seen as a fixed defect) but the myocytes are viable and will benefit from revascularisation (see hibernating myocardium for more details).

Myocardial infarction

In myocardial infarction, there is absent perfusion both when the heart is stressed and at rest (a fixed defect) and the myocytes are not viable. There will be no benefit from revascularisation; (see myocardial infarction for more details).

Imaging techniques

thallium-201 SPECT
- excessive radiation dose (in comparison to Tc-99m MIBI)
- redistribution may occur
- single injection for stress and resting phase
technetium-99m MIBI SPECT
- less radiation dose
- no redistribution
- separate injections for stress and resting phase
FDG-PET (for viability)
- based on the fact that myocardium utilises glucose for metabolism when under effect of ischaemia (hence the ischaemic myocardium will show greater uptake than normal cells)
- under normal circumstances, it utilises fatty acids for energy
- non-viable myocardium will not show any uptake
cardiac MR perfusion imaging
- no ionising radiation exposure
- dynamic imaging with gadolinium for perfusion
- delayed imaging for viability assessment
CT myocardial perfusion imaging
- single phase or dynamic perfusion imaging during stress +/- rest
- coronary arteries can be assessed at the same time