99mTc-sestamibi: its clinical role as a viability agent.
The correlation between the presence of viable myocardium and 99mTc-sestamibi uptake is still to be defined. Preliminary studies indicate that: 1) reduced 99mTc-sestamibi uptake at rest is not necessarily evidence of scar tissue, and 2) its uptake is correlated to the severity of coronary stenosis. To define the relationship between rest thallium-201 and 99mTc-sestamibi uptake in dyssynergic segments, we studied 10 patients with ventricular dysfunction. 99mTc-sestamibi uptake was higher than thallium-201 uptake in normal segments but was similarly reduced in segments perfused by stenotic coronary arteries with or without wall motion abnormalities. Post-revascularization studies of regional wall motion showed that 99mTc-sestamibi had a positive and a negative predictive accuracy in identifying viable segments of 88 and 69%, respectively; these values were significantly lower than that provided by Thallium-201. 99mTc-sestamibi appears to be a primary perfusion agent with a high sensitivity to blood flow reduction at rest; it can be cautiously used as a viability agent in segments with wall motion abnormalities at rest.
Marzullo
P
P
CNR Institute of Clinical Physiology, Pisa, Italy.
Sambuceti
G
G
D000328:Adult; D002470:Cell Survival; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000378:metabolism; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009204:Myocardial Revascularization; D011877:Radionuclide Imaging; D012146:Rest; D017256:Technetium Tc 99m Sestamibi / Q000493:pharmacokinetics; D013794:Thallium Radioisotopes / Q000493:pharmacokinetics; D014018:Tissue Distribution
D013794:Thallium Radioisotopes; D017256:Technetium Tc 99m Sestamibi