A comparison of rest sestamibi and rest-redistribution thallium single photon emission tomography: Possible implications for myocardial viability detection in infarcted patients

Abstract

Thirty patients (26 men, 4 women, mean age 61 +/- 8 years) who had suffered myocardial infarction 15 +/- 6 months previously, were submitted to (1) standard stress-redistribution thallium-201 single photon emission tomography (SPET), (2) rest-redistribution 201T1 SPET and (3) stress-rest technetium-99m sestamibi SPET. Uptake modifications in relation to exercise-induced defects were evaluated in a total of 390 myocardial segments. Tracer uptake was scored as normal (=0), mildly reduced (=1), apparently reduced (=2), severely reduced (=3) or absent (=4). Comparison of stress studies failed to show any statistical difference (58% segmental abnormalities with sestamibi vs 61% with thallium). Uptake abnormalities (score 1-4) were detected in 55% of the segments with sestamibi, 55% with standard thallium redistribution, 55% with early imaging after thallium injection at rest and 54% with 3-h delayed rest imaging (P = NS). Absence of tracer uptake (score = 4) under resting conditions was recorded in 75 (19%) segments with standard 201T1 redistribution, 75 (19%) with rest sestamibi, 70 (18%) with rest 201T1 imaging and 62 (16%) with rst-redistribuion 201T1 (P < 0.05 vs other imaging modalities). Thus, 3-h delayed rest thallium imaging detected reversibility of uptake defects in a significantly higher number of myocardial segments. This finding might have important implications for both tracer and technique selection when myocardial viability is the main clinical issue.

Myocardial viability: What do we need?

“…These findings have been confirmed by others [105][106][107][108][109]. All patients also underwent stress and rest 99~Fc-MIBI planar scintigraphy using a 2-day protocol.…”

“…A number of papers dealing with the role of 99~Tc-MIBI in the identification of viable myocardium have been published [99][100][101][102][103][104][105][106][107]. In most studies, MIBI has been shown to substantially underestimate the amount of viable myocardium in comparison to thallium re-injection.…”

Comparison of Baseline–Nitrate Technetium-99m Sestamibi With Rest–Redistribution Thallium-201 Tomography in Detecting Viable Hibernating Myocardium and Predicting Postrevascularization Recovery

“…The reliability of technetium-99m (Tc-99m) sestamibi in evaluating myocardial viability has not yet been established. The relation of Tc-99m sestamibi uptake and retention with myocardial cell membrane integrity and tissue viability has been demonstrated (14 -16), but human studies (11,(17)(18)(19)(20)(21) have suggested that rest Tc-99m sestamibi could underestimate myocardial viability. Some of these reports are of limited value because they were just comparisons of defect reversibility in Tc-99m sestamibi and Tl-201 imaging (18,19).…”

“…The relation of Tc-99m sestamibi uptake and retention with myocardial cell membrane integrity and tissue viability has been demonstrated (14 -16), but human studies (11,(17)(18)(19)(20)(21) have suggested that rest Tc-99m sestamibi could underestimate myocardial viability. Some of these reports are of limited value because they were just comparisons of defect reversibility in Tc-99m sestamibi and Tl-201 imaging (18,19). More recent data (12,22) have shown that quantitative analysis of Tc-99m sestamibi single-photon emission computed tomography (SPECT) reduces the underestimation of viability compared with Tl-201 imaging.…”

Myocardial reversibility detection. Rest NTG99mTc-MIBI versus201TI reinjection. Preliminary results

“…PET is expensive and confined to relatively few laboratories and thallium-201 is not exactly reliable as PET, mainly because of false negative results. 6,7 Some reports [8][9][10][11] have suggested that in humans rest 99mTc-MIBI underestimate the extent of viable myocardium compared with PET and 2~ imaging. However, taking 99mTc-MIBI into account, it is conceivable that intervention capable of increasing coronary flow during the tracer uptake could improve the detection of viable myocardium.…”