Static Myocardial Dual-Energy (DE) Perfusion and Delayed Enhancement in Detection of Chronic Myocardial Scar Tissue. Comparison with Late Gadolinium Ebhancement MRI

Abstract

Purpose. To compare the performance of static myocardialDECT perfusion imaging (CTA) with DECT delayed enhancement for detection of ischemic myocardial scars using LGE MRI as a diagnostic standard.Materials and Methods. 29 patients (m/f –16/13 mean age 57.6 ± 2.1) with chronic myocardial infarction were prospectively enrolled in the study. The CCTA protocol consisted of prospectively gated static myocardial DECT perfusion imaging (angiographic phase) and DECT delayed enhancement with 8 min delay after contrast media injection. Study was performed with 64-row single-source dual energy CT with fast kilovoltage switching. DECT images were visually assessed for first-pass arterial enhancement deficit and delayed enhancement using iodine distribution maps by 2 observers in comparison with LGE MRI. Sensitivity and specificity, the normalized iodine concentration ratio of normal myocardium and scar tissue were calculated both for both methods.Results. For scar detection static myocardial DECT perfusion had accuracy, sensitivity and specificity 95%, 90%, 95%, resp. vs. delayed DECT – 96%, 88%, 99%, resp. There was no significant difference between accuracy, sensitivity and specificity for DECT perfusion and delayed DECT (p = 0.32). However diagnostic confidence and normalized iodine concentration ratio of normal myocardium and scar for static myocardial DECT perfusion were significantly lower than for delayed DECT (p < 0.0001).Conclusion. DECT CTA and DECT delayed enhancement have a good accuracy for detection of post-infarction scars in comparison with LGE MRI. The overall diagnostic performance of DECT delayed enhancement was better then of static myocardial DECT perfusion imaging. Thus, delayed sequences should not be omitted from CTA standard protocol if the aim is myocardial scar detection.