Quantitative Analysis of a Whole Cardiac Mass Using Dual-Energy Computed Tomography: Comparison with Conventional Computed Tomography and Magnetic Resonance Imaging

Abstract

It is critical to distinguish between cardiac tumors and thrombi because they require different treatment strategies. Although accurate differentiation of these cardiac masses can be challenging, computed tomography (CT) and magnetic resonance imaging (MRI) are promising tools to improve their diagnosis. This study aimed to assess the diagnostic value of a volume-based quantification strategy using dual-energy CT to differentiate between cardiac tumors and thrombi. We prospectively enrolled 41 patients who had a cardiac mass. All patients underwent electrocardiography gated dual-energy CT. Among them, 28 patients underwent late gadolinium enhancement cardiac MRI. For quantitative analysis, the following parameters of the entire cardiac masses were measured: CT attenuation values in Hounsfield units (HU), iodine concentration (mg/ml), and signal intensity (SI) ratio. A mixed effects model was used to evaluate the significance of differences in mean CT attenuation, mean iodine concentration, and SI ratios between the cardiac tumor and thrombus groups. Diagnostic performance of each parameter was evaluated by constructing a receiver operating characteristics curve. A total of 24 cardiac tumors and 19 cardiac thrombi were analyzed. The mean iodine concentration was significantly higher in tumors than in thrombi (tumors: 2.98 ± 0.23; thrombi: 1.79 ± 0.26, p = 0.002). The diagnostic performance of iodine concentration was better than that of post-contrast HU (area under the curve [AUC]: 0.77 vs. 0.51; p < 0.001), and worse than that of SI ratio (AUC: 0.89; p = 0.04) for differentiation of cardiac tumors and thrombi. Dual-energy CT using volume-based iodine measurements can differentiate between cardiac tumors and thrombi.

Radiomics Feature Analysis Using Native T1 Mapping for Discriminating Between Cardiac Tumors and Thrombi

“…LGE cardiovascular MRI has shown a higher diagnostic value for distinguishing cardiac tumors from thrombi compared to other modalities (15,16,43). However, its scope is limited by the need for contrast agents and the delay between contrast injection and image acquisition.…”

“…Previous studies have used many features, such as signal intensity on gradient echo sequence or degree of gadolinium enhancement, both of which are influenced by the image acquisition protocol and the reader's subjectivity (2,11À14). Late gadolinium enhancement (LGE) MRI is one of the established methods for differentiation of cardiac tumors and thrombi; however, it requires contrast agents (15,16).…”

Multi Modality Imaging Features of Cardiac Myxoma

“…Dual energy CT with mean iodine concentration is an accurate approach for defining whether a cardiac mass visibly enhances. 12) …”

“…Dual energy CT with mean iodine concentration is an accurate approach for defining whether a cardiac mass visibly enhances. 12) Functional retrospective cardiac CT is able to demonstrate tumor mobility (Figure 7).…”

“…See Table 2 for a standard MRI protocol for patients with suspected cardiac myxomas. 12) Myxomas can be substantially variable in appearance and of heterogenous signal intensity on MRI owing to myxoid tissue, fibrous tissue, blood and calcification.…”