Reproducibility of the Assessment of Myocardial Function Using Gated Tc-99m-MIBI SPECT and Quantitative Software

Lee, Dong Soo; Cheon, Gi Jeong; Ahn, Ji Young; Chung, June Key; Lee, Myung Chul

Abstract

PURPOSE: We investigated reproducibility of the quantification of left ventricular volume and ejection fraction, and grading of myocardial wall motion and systolic thickening when we used gated myocardial SPECT and Cedars quantification software.
MATERIALS AND METHODS
We performed gated myocardial SPECT in 33 consecutive patients twice in the same position after Tc-99m-MIBI SPECT. We used 16 frames per cycle for the gatingof sequential Tc-99m-MTBI SPECT. After reconstruction, we used Cedars quantitative gated SPECT and calculated ventricular volume and ejection fraction (EF), Wall motion was graded using 5 point score. Wall thickening was graded using 4 point score. Coefficient of variation for re-examination of volume and fraction were calculated. Kappa values (k-value) for assessing reproducibility of wall motion or wall thickening were calculated.
RESULTS
Enddiastolic volumes (EDV) ranged from 58 mi to 248 ml (122 ml +/- 42 ml), endsystolic volumes (ESV) from 20 mi to 174 mi (65 ml +1- 39 ml), and EF from 20% to 68% (51% +/- 14%). Geometric mean of standard deviations of 33 patients was 5.0 ml for EDV, 3.9 ml for ESV and 1.9% for EF. Their average differences were not different from zero (p>0.05). k-value for wall motion using 2 consecutive images was 0.76 (confidence interval: 0.71-0.81). k-value was 0.87 (confidence interval:0.83-0.90) for assessment of wall thickening.
CONCLUSION
We concluded that quantification of functional indices, assessment of wall motion and wall thickening using gated Tc-99m-MIBI SPECT was reproducible and we could use this method for the evaluation of short-acting drug effect.