ABSTRACT
Objective: To compare the sensitivity and specificity between low dose dobutamine stress speckling tracking echocardiography (LDDS-STE) and delayed enhancement MRI (DE-MRI) for assessing viable myocardium (VM) in patients with old myocardial infarction (OMI). Methods: A total of 30 in-hospitalized OMI patients were enrolled, all patients received cardiac MRI and LDDS-STE prior percutaneous coronary intervention (PCI). Radial peak systolic strain (RS) and strain rate (RSr) were analyzed by LDDS-STE at both resting and loading conditions, echocardiography was performed at 1, 3 and 6 months after PCI to observe the cardiac wall motion changes and the improvement of wall motion score was taken as golden standard of VM. Results: 510 left ventricular segments were obtained for analysis in 30 patients and echocardiography indicated 201 segments with abnormal wall motion. Compared with golden standard, the area under ROC curve of RSrest for detecting VM was 0.636 with the sensitivity at 60.0% , specificity at 60.5% and the area under ROC curve of RSLDDS for detecting VM was 0.806 with the sensitivity at 79.1%, specificity at 82.7%; the area under ROC curve of RSrrest for detecting VM was 0.646 with the sensitivity at 60.0% , specificity at 60.5% and the area under ROC curve of RSrLDDS for detecting VM was 0.808 with the sensitivity at 80.0%, specificity at 83.7% which were obviously improved than RSrrest . By DE-MRI, the area under ROC curve for detecting VM was 0.901 with the sensitivity at 90.8%, specificity at 87.1% and accuracy at 89.5%. Conclusion: Both DE-MRI and LDDS-STE can recognize VM in OMI patients; while DE-MRI had the better accuracy and repeatability, cost less time which may provide important basis for predicting the efficacy of PCI and for making the treatment strategy.