Identification of hibernating myocardium by dobutamine stress echocardiography: Comparison with thallium-201 reinjection imaging

The aim of this study was to determine the diagnostic value of dobutamine stress echocardiography (DSE) in the identification of hibernating myocardium and to compare its predictive accuracy with that of thallium-201 reinjection (RI) imaging. The subjects were 26 patients with wall motion abnormalities related to stenosed coronary arteries. DSE predicted postrevascularization improvement in 31 of 33 segments that were considered to be hibernating and identified 8 of 10 nonhibernating segments. In contrast, thallium-201 scintigraphy predicted all 33 hibernating segments when a post-RI myocardial thallium uptake in ischemic areas of ≥50% of the maximum count in normal segments was used as a positive marker of myocardial viability. However, thallium studies predicted only 30 of 33 hibernating segments when thallium redistribution (RD) was used as a marker of viability in delayed or RI images. Among the 10 nonhibernating segments, an uptake of <50% was observed in 4 segments and negative thallium-201 RD was observed in 5 segments. The sensitivity, specificity, and predictive values (PV) of DSE were 94%, 80%, positive PV 94%, and negative PV 80%, respectively. In contrast, the sensitivity, specificity, and PV of thallium-201 RI imaging were 100%, 40%, 85%, and 100% with uptake ≥50% and 91%, 50%, 86%, and 63% with RD, respectively. These results suggest that DSE may be useful for identifying hibernating myocardium and could therefore be helpful in selecting candidates for coronary revascularization.