河合 秀樹

OBJECTIVE: To directly compare coronary arterial stenosis evaluations by hybrid-type iterative reconstruction (IR), model-based IR (MBIR), deep learning reconstruction (DLR), and high-resolution deep learning reconstruction (HR-DLR) on coronary computed tomography angiography (CCTA) in both in vitro and in vivo studies. MATERIALS AND METHODS: For the in vitro study, a total of three-vessel tube phantoms with diameters of 3 mm, 4 mm, and 5 mm and with simulated non-calcified stepped stenosis plaques with degrees of 0%, 25%, 50%, and 75% stenosis were scanned with area-detector CT (ADCT) and ultra-high-resolution CT (UHR-CT). Then, ADCT data were reconstructed using all methods, although UHR-CT data were reconstructed with hybrid-type IR, MBIR, and DLR. For the in vivo study, patients who had undergone CCTA at ADCT were retrospectively selected, and each CCTA data set was reconstructed with all methods. To compare the image noise and measurement accuracy at each of the stenosis levels, image noise, and inner diameter were evaluated and statistically compared. To determine the effect of HR-DLR on CAD-RADS evaluation accuracy, the accuracy of CAD-RADS categorization of all CCTAs was compared by using McNemar's test. RESULTS: The image noise of HR-DLR was significantly lower than that of others on ADCT and UHR-CT (p < 0.0001). At a 50% and 75% stenosis level for each phantom, hybrid-type IR showed a significantly larger mean difference on ADCT than did others (p < 0.05). At in vivo study, 31 patients were included. Accuracy on HR-DLR was significantly higher than that on hybrid-type IR, MBIR, or DLR (p < 0.0001). CONCLUSION: HR-DLR is potentially superior for coronary arterial stenosis evaluations to hybrid-type IR, MBIR, or DLR shown on CCTA. KEY POINTS: Question How do coronary arterial stenosis evaluations by hybrid-type IR, MBIR, DLR, and HR-DLR compare to coronary CT angiography? Findings HR-DLR showed significantly lower image noise and more accurate coronary artery disease reporting and data system (CAD-RADS) evaluation than others. Clinical relevance HR-DLR is potentially superior to other reconstruction methods for coronary arterial stenosis evaluations, as demonstrated by coronary CT angiography results on ADCT and as shown in both in vitro and in vivo studies.

BACKGROUND: Cardiac amyloidosis requires quantitative assessment using technetium-99m pyrophosphate (99mTc-PYP) single-photon emission computed tomography (SPECT)/computed tomography (CT) for adequate discrimination and evaluation of disease extent. This study aimed to evaluate the utility of standardized uptake value (SUV) analysis using 99mTc-PYP SPECT/CT in pathologically-confirmed transthyretin amyloid cardiomyopathy (ATTR-CM). The study also explored the relationship between local uptake heterogeneity and indicators of cardiac impairment. METHODS: Forty patients diagnosed via heart biopsy and genetic analysis (20 ATTR-CM; 4 light-chain amyloidosis, 16 non-amyloidosis) were enrolled. The mean SUVs of the heart and aorta were measured using SPECT images. Discrimination performance was evaluated by comparing each SUV, the heart-to-aorta ratio (rSUVH/Ao), and the heart-to-contralateral-lung ratio with pathological findings serving as the gold standard. Polar maps were analyzed to assess local SUV distribution in patients with ATTR-CM. The coefficient of variation (COV) of myocardial uptake, difference score between the septum and lateral wall (%DS), base-to-apex variability, and total cardiac SUV were calculated and compared with echocardiographic parameters. RESULTS: All metrics were significantly different between the ATTR-CM and non-amyloidosis groups. The rSUVH/Ao effectively differentiated patients with ATTR-CM from those with light-chain or non-amyloidosis. Local myocardial SUV distribution correlated with impaired cardiac function. Notably, COV showed significant correlations with e' (R = 0.782) and E/e' (R =  - 0.625), linking heterogeneity to myocardial stiffness and diastolic dysfunction. Larger %DS, which predominantly reflected the ATTR-CM pattern of high septal uptake, correlated significantly with thinner walls (average wall thickness, R =  - 0.655; relative wall thickness, R =  - 0.486). As the total cardiac SUV increased, the %DS decreased (reflecting more homogeneous distribution), and global longitudinal strain worsened (R = 0.614). These observations indicated that greater impairment was associated with a higher disease burden. CONCLUSIONS: This study demonstrated that quantitative SPECT analysis provides a valuable tool for the diagnostic evaluation and differentiation of ATTR-CM. The rSUVH/Ao offers high discriminatory performance. Local heterogeneity and total myocardial uptake are closely related to the disease burden and extent, as reflected by structural and functional abnormalities on echocardiography. These findings suggest potential relevance to the non-invasive assessment of these aspects of the disease at a single time point.

BACKGROUND: Sarcoidosis is a systemic granulomatous disease that occasionally affects the heart and poses the risks of arrhythmias, heart failure, and sudden cardiac death. CASE SUMMARY: We report a rare case of cardiac sarcoidosis presenting as a large intracardiac mass in a 76-year-old woman that was incidentally detected during a health check-up. Transthoracic echocardiography revealed a 25× 33 mm mobile mass in the left atrium. Cardiac magnetic resonance and 18F-fluorodeoxyglucose positron emission tomography/computed tomography demonstrated heterogeneous enhancement and increased metabolic activity, respectively, raising the suspicion of cardiac sarcoidosis. Bronchoscopic biopsy confirmed the presence of epithelioid granulomas, supporting the diagnosis. Surgical resection was performed because of the size of the mass and the potential for mitral valve obstruction. Histopathology confirmed the presence of non-caseating granulomas consistent with sarcoidosis. Postoperatively, corticosteroid therapy with prednisolone (initially 30 mg/day, tapered to 5 mg/day) was initiated to treat the residual lesions identified on imaging. The residual mass showed regression, with resolution of inflammatory activity, through the use of steroid therapy during follow-up. DISCUSSION: This case report highlights the diagnostic and therapeutic challenges associated with cardiac sarcoidosis presenting as a large intracardiac mass. Our findings underscore the importance of a multidisciplinary approach that utilises advanced imaging techniques, histological confirmation, and tailored management strategies that combine surgical intervention and immunosuppressive therapy for diagnosis and treatment.

BACKGROUND: The efficacy of intravenous steroids (IS) for fulminant myocarditis (FMP) remains controversial. We aimed to compare outcomes in FMP patients who received IS [IS(+)] and those who did not [IS(-)]. METHODS AND RESULTS: Data from 344 patients with histologically confirmed FMP requiring catecholamines or mechanical support were extracted from the Japanese Registry of Fulminant Myocarditis. The primary outcome was a composite of 90-day mortality and heart transplantation. Among the patients (median age 54, 40 % female), 195 received IS, 98 died within 90 days, and 16 died or underwent transplantation after 90 days. The IS(+) group had lower left ventricular ejection fraction and lower ratio of lymphocytic myocarditis, higher use of intra-aortic balloon pumping, Venoarterial extracorporeal membrane oxygenation (VA-ECMO), and intravenous immunoglobulin. Crude analysis showed worse 90-day outcomes in the IS(+) group (36.3 % vs. 19.2 %, P = 0.0021); however, after propensity score matching (PSM), outcomes were similar (26.2 % vs. 24.2 %; P = 0.95). Unadjusted Cox regression indicated worse outcomes with IS (HR 1.95, 95 % CI 1.26-3.04; P = 0.0026), but this was not significant after PSM (HR 1.02, 95 % CI 0.56-1.87; P = 0.95). Among low-risk patients, the IS(-) group showed better outcomes than the IS(+) group post-PSM (P = 0.0031). In the patients with VA-ECMO or ventricular assist devices, early IS (within 2 days of admission) showed comparable prognosis to delayed/no IS, with a trend toward better outcomes post-PSM. CONCLUSIONS: IS effectiveness in FMP patients may vary, showing limited prognostic benefit overall. Careful consideration is warranted in its use for this population.