RESUMO
OBJECTIVES: To evaluate myocardial enhancement of patients with cardiac amyloidosis (CA) using computed tomography (CT). METHODS: Thirteen patients with CA and 11 control patients were examined with first-pass and delayed CT acquisition. A qualitative and quantitative analysis of images was performed. Myocardial attenuation, myocardial signal-to-noise ratio (SNRmyoc), blood pool SNR (SNRblood), contrast-to-noise ratio between blood pool and myocardium (CNRblood-myoc) and relative attenuation index (RAI) defined as variation of myocardial attenuation between delayed and first-pass acquisitions were calculated. RESULTS: Two false negative cases (15 %) and three false positive cases (27 %) were detected on qualitative analysis. SNRmyoc of patients with CA was significantly (p < 0.05) lower on first-pass (4.08 ± 1.9) and higher on delayed acquisition (7.10 ± 2.7) than control patients (6.1 ± 2.2 and 5.03 ± 1.8, respectively). Myocardial attenuation was higher in CA (121 ± 39 HU) than control patients (81 ± 17 HU) on delayed acquisition. CNRblood-myoc was significantly (p < 0.05) lower in CA (1.51 ± 0.7) than control patients (2.85 ± 1.2) on delayed acquisition. The RAI was significantly (p < 0.05) higher in CA (0.12 ± 0.25) than in control patients (-0.56 ± 0.21). CONCLUSION: Dual phase MDCT can detect abnormal myocardial enhancement in patients with CA. KEY POINTS: ⢠CT can detect abnormal first-pass and delayed enhancement in cardiac amyloidosis. ⢠Measurement of relative myocardial enhancement between acquisitions helps to detect cardiac amyloidosis. ⢠CT may provide useful data to diagnose cardiac amyloidosis.
