Evaluation of immediate post-stress wall motion on adenosine stress/rest thallium-201 gated myocardial SPECT

Abstract

As early as 10 min after adenosine stress, immediate post-stress wall motion can be evaluated on adenosine stress/rest Tl-201 gated myocardial SPECT. To widen the applications of Tl-201 in gated SPECT, we investigated the reproducibility of LV parameters (EF, EDV, and ESV), and the diagnostic competency of immediate post-stress wall motion evaluations obtained by adenosine stress/rest Tl-201 gated myocardial SPECT. Myocardial perfusion and wall motion were evaluated using a 5-point scoring system in 20-segment model using Cedas automatic gated software (AutoQUANT 4.3.1). The reproducibilities of LV parameters were examined through repeated acquisition (n=31). Diagnostic competency was evaluated vs. coronary angiography, and multivariate logistic regression analysis was used to determine whether stress abnormal perfusion (SSSp), stress abnormal wall motion (SSSwm), or reversible abnormal wall motion (SDSwm) predict coronary stenosis (>70%) (n=60). Two standard deviations for immediate post-stress wall motion were smaller than those for rest at EF (8.6 vs. 10.7%) and ESV (6.0 ml vs 8.4 ml). Univariate logistic regression analysis identified SSSp (p=0.006), SSSwm (p=0.016), and SDSwm (p=0.020) are significant predictors, but only SSSp (p=0.013) and SDSwm (p=0.039) were found to be significant by multivariate analysis. In addition, SSSwm or SDSwm were able to find undetected coronary artery disease in 54.5% (6/11) of patients with normal perfusion. We conclude that Tl-201 can be successfully applied to gated SPECT for immediate post-stress wall motion evaluation, and that reversible wall motion abnormality on adenosine stress/rest Tl-201 gated myocardial SPECT is an independent predictor of significant coronary artery disease.