Tc-99m-tetrofosmin SPECT for prediction of functional recovery defined by MRI in patients with severe left ventricular dysfunction: Additional value of gated SPECT
Jc. Stollfuss et al., Tc-99m-tetrofosmin SPECT for prediction of functional recovery defined by MRI in patients with severe left ventricular dysfunction: Additional value of gated SPECT, J NUCL MED, 40(11), 1999, pp. 1824-1831
Citations number
29
Categorie Soggetti
Radiology ,Nuclear Medicine & Imaging","Medical Research Diagnosis & Treatment
This study was designed to evaluate gated Tc-99m-tetrofosmin SPECT for pred
iction of functional recovery proven by sequential MRI, Tc-99m-labeled tetr
ofosmin is a recently introduced tracer for myocardial perfusion. However,
its role for viability assessment is still under investigation. Methods: Tc
-99m-tetrofosmin uptake in 19 patients with coronary artery disease and sev
ere left ventricular dysfunction was correlated to regional wall thickening
before and 4.5 +/- 0.8 mo after successful coronary artery bypass grafting
, as derived from corresponding gated short-axis MRI, Preoperative wall thi
ckening determined by gated SPECT was used as an additional parameter for p
rediction of functional outcome. Optimal threshold cutoffs to separate reve
rsible from irreversible dysfunction were determined by receiver operator c
haracteristic (ROC) analysis. Results: The sensitivity and specificity of r
egional Tc-99m-tetrofosmin for prediction of functional recovery was 87% an
d 42%, respectively (cutoff: 50% of maximum tracer retention). The area und
er ROC curves for prediction of functional recovery measured 0.66 +/- 0.01.
Segments with greater than or equal to 50% uptake and impaired but detecta
ble wall thickening determined by gated SPECT had a significantly higher li
kelihood for functional improvement compared with segments with absent wall
thickening (P < 0.05), There was no difference in segments with <50% trace
r retention. There was good agreement for ejection fraction measurements by
MRI and gated SPECT (mean ejection fraction 32 +/- 12 versus 34 +/- 11; r
= 0.71, P < 0.001). Conclusion: Regional Tc-99m-tetrofosmin uptake provided
high sensitivity but limited specificity for prediction of functional reco
very after revascularization, leading to fair overall accuracy. Wall thicke
ning assessment derived from gated SPECT may improve the specificity of Tc-
99m-tetrofosmin uptake for prediction of functional recovery but not the se
nsitivity in low-flow areas, In addition to the assessment of global functi
on, gated data acquisition can be helpful to improve the overall accuracy o
f Tc-99m-tetrofosmin SPECT for prediction of functional recovery after bypa
ss surgery.