Myocardial perfusion imaging

Myocardial perfusion imaging
Myocardial perfusion scan with thallium-201 for the rest images (bottom rows) and Tc-Sestamibi for the stress images (top rows)
Synonyms	Myocardial perfusion scintigraphy
ICD-10-PCS	C22G
MeSH	D055414
OPS-301 code	3-704, 3-721
eMedicine	2114292

Myocardial perfusion imaging or scanning (also referred to as MPI or MPS) is a nuclear medicine procedure that illustrates the function of the heart muscle (myocardium).^[1]

It evaluates many heart conditions, such as coronary artery disease (CAD),^[2] hypertrophic cardiomyopathy and heart wall motion abnormalities. It can also detect regions of myocardial infarction by showing areas of decreased resting perfusion. The function of the myocardium is also evaluated by calculating the left ventricular ejection fraction (LVEF) of the heart. This scan is done in conjunction with a cardiac stress test. The diagnostic information is generated by provoking controlled regional ischemia in the heart with variable perfusion.

Planar techniques, such as conventional scintigraphy, are rarely used. Rather, single-photon emission computed tomography (SPECT) is more common in the US. With multihead SPECT systems, imaging can often be completed in less than 10 minutes. With SPECT, inferior and posterior abnormalities and small areas of infarction can be identified, as well as the occluded blood vessels and the mass of infarcted and viable myocardium.^[3] The usual isotopes for such studies are either thallium-201 or technetium-99m.