Objective: To compare the value of low-dose dobutamine echocardiography (LDDE) and dual-isotope emission simultaneous myocardial perfusion acquisition (technetium-99-m-tetrofosmin/fluorine 18-fluorodeoxy-glucose) single-photon emission computed tomography (DISA-SPECT) for myocardial viability assessment in patients with acute myocardial infarction (MI).
Methods: LDDE and DISA-SPECT were performed in 44 patients within 5-10 days after onset of first acute MI and percutaneous coronary intervention was made thereafter. A 16-segment semi-quantitative scoring model was adopted for both techniques. Wall motion improvement at follow-up (3 months after acute MI) compared with baseline before dobutamine infusion derived from two dimensional images was used as golden criteria for myocardial viability.
Results: The sensitivity, specificity, diagnostic accuracy, positive and predictive values for identification of viable myocardium were 77%, 82%, 79%, 82% and 77%, respectively by LDDE and 85%, 62%, 74%, 71% and 79%, respectively by DISA. No difference was found between LDDE and DISA for identifying viable myocardium in hypokinetic segments (74.1% vs. 77.6%, P > 0.05) but less viable myocardium was detected by LDDE than DISA in akinetic segments (29% vs. 53%, P < 0.01).
Conclusions: Sensitivity was higher while specificity was lower on detecting viable myocardium by DISA compared to LDDE. Combined use of the two techniques could improve viable myocardium detection in patients with acute MI.