The Feasibility of a Model-Based Iterative Reconstruction Technique Tuned for the Myocardium on Myocardial Computed Tomography Late Enhancement.

OBJECTIVES: This study evaluated the feasibility of a model-based iterative reconstruction technique (MBIR) tuned for the myocardium on myocardial computed tomography late enhancement (CT-LE). METHODS: Twenty-eight patients who underwent myocardial CT-LE and late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) within 1 year were retrospectively enrolled. Myocardial CT-LE was performed using a 320-row CT with low tube voltage (80 kVp). Myocardial CT-LE images were scanned 7 min after CT angiography (CTA) without additional contrast medium. All myocardial CT-LE images were reconstructed with hybrid iterative reconstruction (HIR), conventional MBIR (MBIR_cardiac), and new MBIR tuned for the myocardium (MBIR_myo). Qualitative (5-grade scale) scores and quantitative parameters (signal-to-noise ratio [SNR] and contrast-to-noise ratio [CNR]) were assessed as image quality. The sensitivity, specificity, and accuracy of myocardial CT-LE were evaluated at the segment level using an American Heart Association (AHA) 16-segment model, with LGE-MRI as a reference standard. These results were compared among the different CT image reconstructions. RESULTS: In 28 patients with 448 segments, 160 segments were diagnosed with positive by LGE-MRI. In the qualitative assessment of myocardial CT-LE, the mean image quality scores were 2.9 ± 1.2 for HIR, 3.0 ± 1.1 for MBIR_cardiac, and 4.0 ± 1.0 for MBIR_myo. MBIR_myo showed a significantly higher score than HIR (P < 0.001) and MBIR_cardiac (P = 0.018). In the quantitative image quality assessment of myocardial CT-LE, the median image SNR was 10.3 (9.1-11.1) for HIR, 10.8 (9.8-12.1) for MBIR_cardiac, and 16.8 (15.7-18.4) for MBIR_myo. The median image CNR was 3.7 (3.0-4.6) for HIR, 3.8 (3.2-5.1) for MBIR_cardiac, and 6.4 (5.0-7.7) for MBIR_myo. MBIR_myo significantly improved the SNR and CNR of CT-LE compared to HIR and MBIR_cardiac (P < 0.001). The sensitivity, specificity, and accuracy for the detection of myocardial CT-LE were 70%, 92%, and 84% for HIR; 71%, 92%, and 85% for MBIR_cardiac; and 84%, 92%, and 89% for MBIR_myo, respectively. MBIR_myo showed significantly higher image quality, sensitivity, and accuracy than the others (P < 0.05). CONCLUSIONS: MBIR tuned for myocardium improved image quality and diagnostic performance for myocardial CT-LE assessment.

Remote dielectric sensing predicts elevated left atrial pressure in patients with atrial fibrillation.

Background: There are currently no established non-invasive indices of echocardiography for elevated left atrial pressure (LAP) especially in patients with atrial fibrillation (AF). Remote dielectric sensing (ReDS) is a novel non-invasive electromagnetic energy-based technology that quantifies total lung fluid, enabling the monitoring of volume status in patients with heart failure. The utility of ReDS for estimating LAP in patients with AF remains unknown. Methods: We prospectively investigated patients with AF in whom LAP was directly measured during catheter ablation for AF, and ReDS measurements were conducted the day before ablation. Elevated LAP was defined as LAP ≥ 15 mmHg. Results: A total of 61 patients were included (median age 66 years, 38 % female). Among them, 26 patients had elevated LAP. There was a positive correlation between ReDS and LAP (r = 0.363, P = 0.004). Receiver operating characteristic curve analysis for the prediction of elevated LAP demonstrated that the best cut-off value of ReDS was 30 %, with a sensitivity of 65 %, specificity of 69 %, and an area under the curve of 0.703 (95 % confidence interval 0.568-0.837). Multivariate logistic regression analysis revealed that ReDS was an independent predictor of elevated LAP, among covariates including left ventricular ejection fraction, the ratio of early transmitral flow velocity to septal mitral annular early diastolic velocity, and left atrial volume index. Conclusions: Our results suggest ReDS could be a valuable marker of elevated LAP even in patients with AF. Further studies are needed to elucidate the effectiveness of a ReDS-guided decongestive strategy in patients with heart failure.

Feasibility of left atrial strain assessment using cardiac computed tomography in patients with paroxysmal atrial fibrillation.

PURPOSE: To evaluate the feasibility of left atrial strain (LAS) assessment using cardiac computed tomography (CT) in patients with paroxysmal atrial fibrillation (PAF). METHODS: This retrospective single-center study included 98 patients with PAF who underwent cardiac CT and echocardiography before the first catheter ablation. LAS was analyzed using cardiac CT (CT-LAS) and speckle-tracking echocardiography (STE; STE-LAS). LA reservoir (LASr), conduit (LASc), and pump strain (LASp) were calculated by averaging LAS measured in 4- and 2-chamber views. The results were compared using Pearson's correlation coefficients, paired t-tests, and Bland-Altman analysis. Intraclass correlation coefficients (ICCs) were used to evaluate reproducibility. RESULTS: CT-LAS could be analyzed in all patients, while STE-LAS could be analyzed in 53 (54%) patients. LASr, LASc, and LASp showed significant correlations between CT- and STE-LAS: LASr, r = 0.68, p < 0.001; LASc, r = 0.47, p < 0.001; LASp, r = 0.67, p < 0.001. LASr, LASc, and LASp of CT- and STE-LAS were 23.7 ± 6.0% and 22.1 ± 6.7%, 11.1 ± 3.6% and 11.1 ± 4.1%, and 12.6 ± 4.6% and 11.0 ± 4.1%, respectively. LASr and LASp were significantly higher in CT-LAS than that in STE-LAS (p = 0.023 for LASr and p = 0.001 for LASp). CT-LAS showed excellent reproducibility. The intra- and interobserver ICCs were 0.96 to 0.99 and 0.89 to 0.90, respectively. CONCLUSION: CT-LAS was successfully analyzed in more patients than STE-LAS and was highly reproducible. The findings suggest that CT-LAS is feasible for patients with PAF.

Association between gardening activity and frailty in patients with heart failure.

Objective Frailty is common in patients with heart failure (HF). Given that gardening demands regular physical activity and offers therapeutic relaxation benefits, this activity may reduce frailty. We investigated the association between gardening activities and frailty in patients with HF. Methods, patients, or materials Between August 2022 and March 2023, we surveyed patients at risk of HF and those with HF who regularly attended a cardiology outpatient clinic. Gardening activities were defined as the ongoing cultivation of flowers, vegetables, or fruits for more than a year. The questionnaire assessed the presence or absence of gardening activities as well as the frequency, duration per session, years of experience, and scale of such activities. We calculated the frailty index. Frailty was defined as a frailty index of 0.25 or greater. Results Of the 1,277 respondents, 69% engaged in gardening and 35% were frail. After adjusting for multiple confounding factors, gardening activities showed an inverse association with frailty [odds ratio = 0.723, 95% confidence interval (0.533-0.981)]. Moreover, frailty and the frailty index showed an inverse association with more extended and large-scale gardening activities. Conclusion Gardening activities were thus found to be associated with a low prevalence of frailty in patients with HF.

Incremental value of tricuspid annular enlargement to progressive tricuspid regurgitation in patients with longstanding persistent atrial fibrillation.

Tricuspid annular enlargement in patients with atrial fibrillation (AF) can induce tricuspid regurgitation (TR). However, risk factors associated with TR progression in patients with AF have not been defined. This study aimed to clarify an association between tricuspid annular diameter (TAD) and TR progression in patients with longstanding persistent AF. We retrospectively analyzed data from 228 patients who had longstanding persistent AF for > 1 year and mild or less TR on baseline echocardiograms. We defined significant TR as moderate or greater TR, graded according to the jet area and vena contracta. The optimal cut-off value of the TAD index (TADI), based on body surface area for predicting progression to significant TR, was estimated using receiver operating characteristic (ROC) curves. The independence and incremental value of the TADI were evaluated using multivariate Cox proportional hazard regression analysis and likelihood ratio tests. Over a median follow-up of 3.7 years, 55 (24.1%) patients developed significant TR. The optimal cut-off value of 21.1 mm/m2 for the TADI at baseline and ROC curves predicted TR progression with 70.4% sensitivity and 86% specificity. Furthermore, TADI was an independent predictor of TR progression (hazard ratio, 1.32; 95% confidence interval, 1.17-1.49, P < 0.001) and had a significant incremental value that exceeded that of models constructed using clinical parameters. In conclusion, TADI was significantly associated with TR progression and was an independent predictor of TR progression in longstanding persistent AF.

Multimorbidity of Allergic Diseases Is Associated With Functional Gastrointestinal Disorders in a Young Japanese Population.

Background/Aims: Although certain allergic diseases have been reported to be associated with the prevalence of functional dyspepsia (FD) and irritable bowel syndrome (IBS), it is unclear whether the presence of multiple allergic diseases further increases the prevalence of FD and IBS. The aim of this study is to determine this issue in young people. Methods: A cohort of 8923 Japanese university students was enrolled and diagnoses of FD and IBS were confirmed using Rome III criteria. Allergic disorders diagnosed at medical institutions were obtained by means of a self-administered questionnaire. Results: The prevalence of FD, IBS, and their overlap was found to be 1.9%, 6.5%, and 1.1%, respectively. Pollen allergy was independently positively correlated with FD, IBS, and overlap of FD and IBS. Allergic rhinitis was positively linked to IBS. Drug allergy was positively associated with FD. The presence of multiple allergic diseases was positively correlated with FD and IBS (FD: adjusted OR for 2 allergic diseases: 1.95 [95% CI, 1.24-2.98], P for trend = 0.003; and IBS: adjusted OR for 1 allergic disease: 1.40 [95% CI, 1.15-1.69], 2 allergic diseases 1.47 [95% CI, 1.12-1.91], and 3 or more allergic diseases: 2.22 [95% CI, 1.45-3.28], P for trend = 0.001). Additionally, the concomitant existence of multiple allergic diseases was also demonstrated to have a trend that correlated with the overlap of FD and IBS (P for trend = 0.018). Conclusion: Allergic disease multimorbidity is positively correlated with the prevalence of FD and IBS in a young population.

Utility of RAND/UCLA appropriateness method in validating multiple-choice questions on ECG.

OBJECTIVES: This study aimed to investigate the utility of the RAND/UCLA appropriateness method (RAM) in validating expert consensus-based multiple-choice questions (MCQs) on electrocardiogram (ECG). METHODS: According to the RAM user's manual, nine panelists comprising various experts who routinely handle ECGs were asked to reach a consensus in three phases: a preparatory phase (round 0), an online test phase (round 1), and a face-to-face expert panel meeting (round 2). In round 0, the objectives and future timeline of the study were elucidated to the nine expert panelists with a summary of relevant literature. In round 1, 100 ECG questions prepared by two skilled cardiologists were answered, and the success rate was calculated by dividing the number of correct answers by 9. Furthermore, the questions were stratified into "Appropriate," "Discussion," or "Inappropriate" according to the median score and interquartile range (IQR) of appropriateness rating by nine panelists. In round 2, the validity of the 100 ECG questions was discussed in an expert panel meeting according to the results of round 1 and finally reassessed as "Appropriate," "Candidate," "Revision," and "Defer." RESULTS: In round 1 results, the average success rate of the nine experts was 0.89. Using the median score and IQR, 54 questions were classified as " Discussion." In the expert panel meeting in round 2, 23% of the original 100 questions was ultimately deemed inappropriate, although they had been prepared by two skilled cardiologists. Most of the 46 questions categorized as "Appropriate" using the median score and IQR in round 1 were considered "Appropriate" even after round 2 (44/46, 95.7%). CONCLUSIONS: The use of the median score and IQR allowed for a more objective determination of question validity. The RAM may help select appropriate questions, contributing to the preparation of higher-quality tests.

Right ventricular papillary muscle crossing the moderator band mimicked infective endocarditis: the utility of multimodal imaging.

Right-sided infective endocarditis (RSIE) generally carries a positive prognosis; however, it can result in complications such as heart failure, underscoring the importance of prompt diagnosis. While echocardiography serves as the standard diagnostic tool, it may occasionally face challenges in distinguishing between normal structures and vegetations. In this report, we present the case of a 60-year-old man diagnosed with pyogenic vertebral osteomyelitis, alongside suspected coexisting RSIE. During both transthoracic and transesophageal echocardiography, a rod-like mobile structure was observed adjacent to the right ventricular moderator band. However, confirming its nature as an infective vegetation proved challenging. Despite the inconclusive diagnosis of IE by echocardiography, the positron emission tomography/computed tomography (PET/CT) scan and cardiac magnetic resonance imaging (MRI) played a pivotal role in distinguishing between normal structures and vegetations. Since IE could develop life-threatening events, the role of multimodal imaging is of paramount importance. This case serves as a compelling example of the diagnostic value through the integration of PET/CT and MRI in ruling out IE.

A prediction model for estimating NT-proBNP in a general Japanese population: the Toon Health Study.

AIMS: As part of the Toon Health Study, which is an ongoing population-based cohort study, we aimed to develop a prediction model for N-terminal pro-brain natriuretic peptide (NT-proBNP) in a general Japanese population. We sought to explore the influence of various demographic and clinical factors on NT-proBNP levels and assess the model's performance. In addition, our objectives included internal validation and investigation of the diagnostic potential of the observed-to-predicted NT-proBNP ratio (OPR) at baseline for predicting the risk of heart failure with preserved ejection fraction (HFpEF). METHODS AND RESULTS: In this prospective cohort study, participants were recruited from Toon City, Japan, as part of the larger Toon Health Study, focusing on cardiovascular risk factors. We measured the NT-proBNP levels and used linear regression with penalization (ridge regression) to develop the model. The model incorporated 10 prespecified predictors (age, gender, body mass index, diastolic blood pressure, heart rate, haemoglobin, albumin, total cholesterol, haemoglobin A1c, and estimated glomerular filtration rate) and underwent assessment using R2 and root mean squared error (RMSE). Internal validation was conducted through bootstrapping. In a post hoc analysis, we explored the OPR's diagnostic potential using 5 year follow-up data (n = 636) to predict the elevation of NT-proBNP > 125 pg/mL at the 5 year follow-up as the risk of HFpEF. A total of 2505 participants (age: 60.4 ± 12.9 years, men: 35%) were enrolled in this study. There was a linear relationship between the observed and predicted values of NT-proBNP in which the logarithm of observed NT-proBNP was <6, which corresponds to 403 pg/mL in NT-proBNP. The prediction model demonstrated satisfactory performance (R2: 0.291, RMSE: 0.688), with age identified as a dominant predictor. The stability of the model was underscored by the internal validation. The OPR at baseline predicted NT-proBNP > 125 pg/mL at the 5 year follow-up with an area under the curve of 0.793. CONCLUSIONS: This study introduces the first prediction model for NT-proBNP in a general Japanese population. Although the model has acceptable performance, ongoing refinement is essential. Our transparent approach to model development, alongside a web-based interactive tool, lays the groundwork for further improvements and external validation. The OPR holds potential for predicting the future risk of HFpEF. This research contributes to understanding the nuanced influence of patient backgrounds on levels of NT-proBNP in asymptomatic individuals within the context of a broader population-based cohort study.

Smoking and secondhand smoke exposure and carotid intima-media thickness: Baseline data from the Aidai Cohort Study in Japan.

INTRODUCTION: Epidemiological evidence regarding the relationship between smoking and secondhand smoke (SHS) exposure and carotid intima-media thickness (CIMT) has been limited in Asian populations. Employing baseline data from the Aidai Cohort Study, Japan, we evaluated the evidence in this cross-sectional study. METHODS: Study subjects were 727 men aged 35-88 years and 1297 women aged 34-85 years. Information on smoking, SHS exposure, and confounders was obtained through a self-administered questionnaire. An automated carotid ultrasonography device was used to measure the right and left CIMT. The greatest CIMT measurement in the left or right common carotid artery was considered the maximum CIMT, and a maximum CIMT >1.0 mm was indicative of carotid wall thickening. Age, alcohol consumption, leisure time physical activity, hypertension, dyslipidemia, diabetes mellitus, body mass index, waist circumference, employment, and education level were adjusted at one time. RESULTS: The prevalence of carotid wall thickening was 13.0%. The prevalence of never smoking was 30.5% in men and 90.1% in women. Among those who had never smoked, the prevalence of never SHS exposure at home and work was 74.3% and 48.2% in men and 38.3% and 56.3% in women, respectively. Active smoking and pack-years of smoking were independently positively related to carotid wall thickening regardless of sex, although the association with current smoking in women was not significant. Independent positive relationships were shown between former smoking and pack-years of smoking and maximum CIMT in men but not in women. No significant relationships were found between SHS exposure at home and work and carotid wall thickening or maximum CIMT in either men or women. CONCLUSIONS: Active smoking, especially pack-years of smoking, was positively associated with carotid wall thickening in both sexes. Such positive associations with maximum CIMT were found only in men; however, interactions between smoking and sex were not significant.

Feasibility of four-dimensional similarity filter for radiation dose reduction in dynamic myocardial computed tomography perfusion imaging.

Rationale and objectives: We aimed to evaluate the impact of four-dimensional noise reduction filtering using a four-dimensional similarity filter (4D-SF) on radiation dose reduction in dynamic myocardial computed tomography perfusion (CTP). Materials and methods: Forty-three patients who underwent dynamic myocardial CTP using 320-row computed tomography (CT) were included in the study. The original images were reconstructed using iterative reconstruction (IR). Three different CTP datasets with simulated noise, corresponding to 25%, 50%, and 75% reduction of the original dose (300 mA), were reconstructed using a combination of IR and 4D-SF. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were assessed, and CT-derived myocardial blood flow (CT-MBF) was quantified. The results were compared between the original and simulated images with radiation dose reduction. Results: The median SNR (first quartile-third quartile) at the original, 25%-, 50%-, and 75%-dose reduced-simulated images with 4D-SF was 8.3 (6.5-10.2), 16.5 (11.9-21.7), 15.6 (11.0-20.1), and 12.8 (8.8-18.1) and that of CNR was 4.4 (3.2-5.8), 6.7 (4.6-10.3), 6.6 (4.3-10.1), and 5.5 (3.5-9.1), respectively. All the dose-reduced-simulated CTPs with 4D-SF had significantly higher image quality scores in SNR and CNR than the original ones (25%-, 50%-, and 75%-dose reduced vs. original images, p < 0.05, in each). The CT-MBF in 75%-dose reduced-simulated CTP was significantly lower than 25%-, 50%- dose-reduced-simulated, and original CTPs (vs. 75%-dose reduced-simulated images, p < 0.05, in each). Conclusion: 4D-SF has the potential to reduce the radiation dose associated with dynamic myocardial CTP imaging by half, without impairing the robustness of MBF quantification.

Acute Lymphocytic Myocarditis With Mobile Left Ventricular Thrombus.

A left ventricular thrombus (LVT) in cardiac disease is associated with various adverse events. To understand the risk of thromboembolism, it is necessary to recognize when LVT is most likely to occur. We present a case of acute lymphocytic myocarditis in a young patient, where the LVT manifestation occurred within 48 hours after the beginning of the disease and was treated by thrombectomy. We have not found any reports of LVT formation earlier than in this case. Patients with acute myocarditis are younger, at a median age of 34 years, and the social impact of embolic complications is considerable. Echocardiography is effective in detecting LVT noninvasively in low- and high-risk patients. Patients with myocarditis can benefit from careful observation by echocardiography.