Diagnostic accuracy of cardiac CT attenuation for anemia detection and severity grading

Background: Anemia is a prevalent hematological disorder associated with substantial morbidity among hospitalized patients. This study aimed to evaluate the diagnostic accuracy of non-contrast cardiac computed tomography (CT) attenuation measurements obtained from different cardiac regions for detecting anemia and grading its severity. Methods: This cross-sectional study included ۳۳۶ patients who underwent non-contrast thoracic CT imaging. Attenuation values were measured in the left ventricle, right ventricle, interventricular septum, and aortic arch and were compared with hemoglobin levels obtained from complete blood count tests. ROC curve analysis, independent-samples t-tests, Mann-Whitney U tests, one-way ANOVA, and correlation analyses were performed to evaluate diagnostic performance and subgroup differences. Significance was set at P-Value < ۰.۰۵. Results: Aortic arch attenuation demonstrated the highest diagnostic accuracy for overall anemia detection (Area under the curve [AUC] = ۰.۶۶۸; Sensitivity = ۷۱.۳%; Specificity = ۵۵.۹%), followed by left ventricular attenuation (AUC = ۰.۶۳۵; Sensitivity = ۴۴.۰%; Specificity = ۷۶.۵%). Diagnostic performance improved for moderate to severe anemia (AUCs ranging from ۰.۶۹۰ to ۰.۷۵۷), whereas discrimination of mild anemia remained limited (AUCs ≤ ۰.۵۸۹). Attenuation values in the left ventricle, right ventricle, and aortic arch showed significant inverse correlations with hemoglobin levels (Spearman’s rho = -۰.۲۷۵ to -۰.۲۹۷; P-Value < ۰.۰۰۱), while no significant association was observed in the septum. Gender-stratified analyses showed consistent reductions in attenuation among anemic patients of both genders. Conclusion: Non-contrast cardiac CT attenuation measurements showed statistically significant associations with hemoglobin levels but demonstrated limited discriminatory performance for anemia detection, particularly in mild cases. Attenuation values obtained during routine thoracic imaging may provide complementary opportunistic information; however, further validation studies are required before clinical implementation.

کلیدواژه ها:

Anemia ، Diagnostic Imaging ، Hemoglobin ، Non-Contrast CT ، Thoracic