Cardiac magnetic resonance imaging detection of intramyocardial hemorrhage in patients with ST-elevated myocardial infarction: comparison between susceptibility-weighted imaging and T1/T2 mapping techniques.

Background: Susceptibility-weighted imaging (SWI) and T1/T2 mapping can be used to detect reperfusion intramyocardial hemorrhage (IMH) in ST-segment elevation myocardial infarction (STEMI) patients. However, the sensitivity and accuracy of the SWI and T1/T2 mapping sequences were not systematically compared. The study aimed to evaluate image quality and diagnostic performance of SWI in patients with IMH, compared with T1/T2 mapping. Methods: A prospective study was conducted on consecutive acute STEMI patients who were recruited from January to July 2022. Within 2-6 days after reperfusion treatment, all patients underwent a 3T cardiac magnetic resonance (CMR) examination, including T2-weighted short-tau inversion recovery (T2W-STIR), T1/T2 mapping, and SWI. A total of 36 patients [age, 56.50±17.25 years; males, 83.33% (30/36)] were enrolled. The relative infarct-remote myocardium signal intensity ratio (SIinfarct-remote) and contrast-to-noise ratio (CNR) were calculated for each patient on T1/T2 mapping and SWI, and the difference between relative signal intensity-to-noise ratio (rSNR) in the IMH (rSNRIMH) was measured for IMH patients on T1/T2 mapping and SWI. SIinfarct-remote, CNR, and rSNRIMH were compared among the three sequences. Receiver operating characteristic (ROC) analyses were used to evaluate the diagnostic performance of three sequences by SIinfarct-remote and visual assessment. Results: A total of 26 (72.22%) patients had IMH. Quantitatively, the SIinfarct-remote of three sequences had excellent diagnostic performance for detecting IMH [SWI area under the curve (AUC) =1.000, 95% confidence interval (CI): 1.000-1.000 vs. T1 mapping AUC =0.954, 95% CI: 0.885-1.000 vs. T2 mapping AUC =0.985, 95% CI: 0.955-1.000; SWI vs. T1 mapping, P=0.300; SWI vs. T2 mapping, P=0.188; T1 mapping vs. T2 mapping, P=0.302). Qualitatively, three sequences had similar performance on detecting IMH (SWI AUC =0.895, 95% CI: 0.784-1.000; T1 mapping AUC =0.835, 95% CI: 0.711-0.958; and T2 mapping AUC =0.855, 95% CI: 0.735-0.974; SWI vs. T1 mapping, P=0.172; SWI vs. T2 mapping, P=0.317; T1 mapping vs. T2 mapping, P=0.710). The rSNRIMH was highest in T1 mapping, followed by T2 mapping and SWI, but SWI had the highest CNR. Conclusions: SWI, as well as T1/T2 mapping, is a feasible and accurate approach for clinical diagnosis of IMH with excellent performance.

The major factor of left ventricular systolic dysfunction in patients with cardiac amyloidosis: Amyloid overload or microcirculation impairment?

Purpose: Amyloid overload and microcirculation impairment are both detrimental to left ventricular (LV) systolic function, while it is not clear which factor dominates LV functional remodeling in patients with cardiac amyloidosis (CA). The purpose of this study was to investigate the major factor of LV systolic dysfunction using cardiac magnetic resonance imaging. Materials and methods: Forty CA patients and 20 healthy controls were included in this study. The CA group was divided into two subgroups by the left ventricular ejection fraction (LVEF): patients with reduced LVEF (LVEF < 50%, rLVEF), and patients with preserved LVEF (LVEF ≥ 50%, pLVEF). The scanning sequences included cine, native and post-contrast T1 mapping, rest first-pass perfusion and late gadolinium enhancement. Perfusion and mapping parameters were compared among the three groups. Correlation analysis was performed to evaluate the relationship between LVEF and mapping parameters, as well as the relationship between LVEF and perfusion parameters. Results: Remarkably higher native T1 value was observed in the rLVEF patients than the pLVEF patients (1442.2 ± 85.8 ms vs. 1407.0 ± 93.9 ms, adjusted p = 0.001). The pLVEF patients showed significantly lower slope dividing baseline signal intensity (slope%BL; rLVEF vs. pLVEF, 55.1 ± 31.0 vs. 46.2 ± 22.3, adjusted p = 0.001) and a lower maximal signal intensity subtracting baseline signal intensity (MaxSI-BL; rLVEF vs. pLVEF, 43.5 ± 23.9 vs. 37.0 ± 18.6, adjusted p = 0.003) compared to the rLVEF patients. CA patients required more time to reach the maximal signal intensity than the controls did (all adjusted p < 0.01). There was no significant correlation between LVEF and first-pass perfusion parameters, while significant negative correlation was observed between LVEF and native T1 (r = -0.434, p = 0.005) in CA patients. Conclusion: Amyloid overload in the myocardial interstitium may be the major factor of LV systolic dysfunction in CA patients, other than microcirculation impairment.

Diastolic dysfunction assessed by cardiac magnetic resonance imaging tissue tracking on normal-thickness wall segments in hypertrophic cardiomyopathy.

OBJECTIVES: Myocardial strain is reported to be a sensitive indicator of myocardial mechanical changes in patients with hypertrophic cardiomyopathy (HCM). The changes in the mechanics of the myocardium of normal wall thickness (< 12 mm) have yet to be well studied. This study aimed to evaluate the function of myocardial segments of normal thickness in patients with HCM. METHODS: Sixty-three patients with HCM and 30 controls were retrospectively enrolled in this retrospective study. Cine imaging, native and post-contrast T1 maps, T2 maps, and late gadolinium enhancement were performed. In addition, regional myocardial strain was assessed by cardiac magnetic resonance-tissue tracking. Strain parameters were compared between the controls and HCM patients with segments of the myocardium of normal thickness. Subgroup analysis was conducted in obstructive and non-obstructive HCM. Lastly, p < 0.05 was considered statistically significant. RESULTS: In normal-thickness myocardial segments of HCM (n = 716), diastolic peak strain rates (PSRs) were significantly lower than in the control group (n = 480) (radial, - 2.43 [- 3.36, - 1.78] vs. - 2.67 [- 3.58, - 1.96], p = 0.002; circumferential, 1.28 [1.01,1.60] vs. 1.39 [1.14, 1.78], p < 0.001; and longitudinal, 1.16 [0.75,1.51] vs. 1.28 [0.90, 1.71], p < 0.001). The normal-thickness segments showed no significant difference in systolic PSRs between HCM and the controls. In the subgroup analysis, significantly decreased diastolic PSRs were noted in both obstructive and non-obstructive HCM, compared with the controls (p < 0.05). CONCLUSIONS: Diastolic changes in myocardial mechanics were observed in normal-thickness segments of HCM, occurring before morphological remodeling and systolic dysfunction developed. This finding contributed to a better understanding of the mechanical pathophysiology of HCM with preserved left ventricular ejection fraction. It may potentially aid in predicting disease progression and risk stratification.

Subtraction Improves the Accuracy of Coronary CT Angiography in Patients with Severe Calcifications in Identifying Moderate and Severe Stenosis: A Multicenter Study.

RATIONALE AND OBJECTIVES: To investigate the diagnostic accuracy of subtraction coronary computed tomographic angiography (CCTAsub) in identifying ≥ 50% and ≥ 70% coronary stenosis in patients with different degrees of calcification. MATERIALS AND METHODS: In this study, 180 patients with coronary calcified plaques who underwent both coronary CT angiography and invasive coronary angiography (ICA) were prospectively enrolled at five centers. Patients were divided into three groups according to the Agatston score: group A (low to moderate, < 400), group B (high, 400-999), and group C (very high, ≥ 1000). Diagnostic accuracies estimated by area under the receiver operating characteristic curve (AUC) were compared between conventional CCTA (CCTAcon) and CCTAsub, with ICA as a reference standard. RESULTS: There were 86 patients in group A, 44 in group B, and 50 in group C. In identifying ≥ 70% coronary stenosis, subtraction improved the diagnostic accuracies on a per-segment basis in group B (AUC: 0.80 vs 0.92, p = 0.001) and group C (AUC: 0.75 vs 0.84, p = 0.001) after subtraction. When identifying ≥ 50% coronary stenosis, the per-segment AUC of CCTAsub in group B and C were significantly higher than that in CCTAcon (group B: 0.81 vs 0.92, p < 0.001; group C: 0.77 vs 0.88, p < 0.001). However, no improvement was observed in group A. CONCLUSION: Subtraction achieved better diagnostic accuracy in patients with Agatston score ≥ 400, both in identifying ≥ 50% and ≥ 70% coronary stenosis, which was instructive for the application of subtraction in clinical practice.

Cardiac involvement in patients 1 year after recovery from moderate and severe COVID-19 infections.

Background: Some patients suffered persistent cardiac symptoms after hospital discharge following COVID-19 infection, including chest tightness, chest pain, and palpitation. However, the cardiac involvement in these patients remains unknown. The purpose of this study was to investigate the effect of COVID-19 infection on the cardiovascular system after 1 year of recovery in patients hospitalized with persistent cardiac symptoms. Materials and methods: In this prospective observational study, a total of 32 patients who had COVID-19 (11 diagnosed as severe COVID-19 and 21 as moderate) with persistent cardiac symptoms after hospital discharge were enrolled. Contrast-enhanced cardiovascular magnetic resonance (CMR) imaging was performed on all patients. Comparisons were made with age- and sex-matched healthy controls (n = 13), and age-, sex- and risk factor-matched controls (n = 21). Further analysis was made between the severe and moderate COVID-19 cohorts. Results: The mean time interval between acute COVID-19 infection and CMR was 462 ± 18 days. Patients recovered from COVID-19 had reduced left ventricular ejection fraction (LVEF) (p = 0.003) and increased extracellular volumes (ECVs) (p = 0.023) compared with healthy controls. Focal late gadolinium enhancement (LGE) was found in 22 (68.8%) patients, mainly distributed linearly in the septal mid-wall or patchily in RV insertion point. The LGE extent in patients with severe COVID-19 was higher than that in patients with moderate COVID-19 (p = 0.009). Conclusion: This 1-year follow-up study revealed that patients with persistent cardiac symptoms, after recovering from COVID-19, had decreased cardiac function and increased ECV compared with healthy controls. Patients with COVID-19 predominately had a LGE pattern of septal mid-wall or RV insertion point. Patients with severe COVID-19 had greater LGE extent than patients with moderate COVID-19.

A potential biomarker based on clinical-radiomics nomogram for predicting survival and adjuvant chemotherapy benefit in resected node-negative, early-stage lung adenocarcinoma.

BACKGROUND: We aimed to construct a clinical-radiomics nomogram to predict disease-free survival (DFS) and the added survival benefit of adjuvant chemotherapy (ACT) for node-negative, early-stage (I-II) lung adenocarcinoma (ADC). METHODS: In this retrospective study including 310 patients from two independent cohorts, the CT-derived radiomics features were selected by least absolute shrinkage and selection operator Cox regression to generate a radiomics signature associated with DFS. The radiomics signature was incorporated to construct a clinical-radiomics nomogram along with the independent clinical risk predictors. The model performance was evaluated with reference to discrimination quantified by Harrell concordance index (C-index), integrated discrimination improvement (IDI) and net reclassification index (NRI), calibration and clinical utility. The risk score (RS) for clinical-radiomics nomogram was calculated. The association between ACT and survival benefit was assessed in high and low RS subgroup. RESULTS: The clinical-radiomics nomogram achieved the highest C-index of 0.822 [95% confidence interval (CI): 0.769, 0.876] in training cohort and 0.802 (95% CI: 0.716, 0.888) in validation cohort. The incorporation of radiomics signature into clinical-radiomics nomogram showed an incremental benefit over clinical nomogram according to the improved NRI and IDI. The calibration curves and decision curve analysis further verified the clinical utility of clinical-radiomics nomogram. Further, patients with high RS based on clinical-radiomics nomogram were more prone to benefit from ACT. CONCLUSIONS: The clinical-radiomics nomogram approach can feasibly conduct risk prediction and have potential to identify the beneficiaries of ACT among patients with node-negative, early-stage ADC, which might serve as a helpful tool in informing therapeutic decision-making.

Novel imaging phenotypes of naïve asthma patients with distinctive clinical characteristics and T2 inflammation traits.

Objective: This study aims to describe the imaging features of naïve asthma patients, defined as not receiving corticosteroids or other asthma medications for at least 1 month, and their association with therapeutic response, and to discover novel unbiased imaging phenotypes. Methods: A total of 109 naïve asthma patients and 50 healthy controls were enrolled in this study. Clinical data and imaging indices of high-resolution computed tomography were collected. The correlation between imaging indices and clinical features was analyzed. Cluster analyses were adopted to determine three novel imaging phenotypes. Results: Compared with healthy controls, naïve asthma patients presented higher scores of airway remodeling, bronchiectasis, and mucus plugs. Mean airway wall area (WA)% was inversely correlated with mid-expiratory flow velocity% predicted. The extent score of bronchiectasis was positively correlated with smoking history and significantly increased in the high mucus group. Mucus plugs were related to improving lung function and type 2 (T2) inflammation, as assessed by sputum and blood eosinophils and fraction of exhaled nitric oxide. Cluster 1 patients had a high proportion of emphysema, the best lung function, and the lowest T2 inflammation; cluster 2 patients had severe airway remodeling, relatively good lung function, and moderate T2 inflammation; cluster 3 patients had severe airway remodeling, mucus plugs, and bronchiectasis, and showed the worst lung function and highest T2 inflammation. Conclusion: Naïve asthma patients had the imaging traits of airway remodeling, bronchiectasis, and mucus plugs. The unbiased imaging phenotypes had good consistency with clinical characteristics, therapeutic response, and T2 inflammation expression in naïve asthma patients.

The hsa_circRNA_102049 mediates the sorafenib sensitivity of hepatocellular carcinoma cells by regulating Reelin gene expression.

A growing body of research has illuminated that non-coding RNAs (ncRNAs) plays an important role in the development of drug resistance in hepatocellular carcinoma (HCC) cells. The expression profiles of differential expressed genes (DEGs) and ncRNAs related to the sorafenib resistance in HCC cells were analyzed according to the Gene Expression Omnibus (GEO) dataSets and The Cancer Genome Atlas (TCGA) datasets. Bioinformatics technology was used to construct the interaction network of DEGs and ncRNAs. Cell transfection, dual-luciferase reporter assay, Western blot, cell counting kit-8 (CCK-8), flow cytometry and quantitative real-time polymerase chain reaction(qRT-PCR) were used to study the mechanism of sorafenib resistance in HepG2 cells and Huh-7 cells. The expression of reelin (RELN) and secretagogin (SCGN) were the only down-regulated in sorafenib-resistant HCC cells. The results showed that RELN gene demethylation reversed the cytotoxic of sorafenib on HepG2 cells and Huh-7 cells. Hsa_circRNA_102049 over-expression promoted the sensitivity of HepG2 cells and Huh-7 cells to sorafenib, hsa_circRNA_102049 up-regulated the expression of RELN gene by sponging hsa-miR-214-3p. The resistance to sorafenib in RELN knockout HepG2 cells and Huh-7 cells could be reverted by has-circRNA_102049. These findings support targeting of hsa_circRNA_102049 and RELN in sorafenib-treated HCC cells as a novel intervention, which is expected to overcome sorafenib resistance of HCC cells.

Discriminating malignant from benign testicular masses using machine-learning based radiomics signature of appearance diffusion coefficient maps: Comparing with conventional mean and minimum ADC values.

PURPOSE: To develop a machine-learning-based radiomics signature of ADC for discriminating between benign and malignant testicular masses and compare its classification performance with that of minimum and mean ADC. METHODS: A total of ninety-seven patients with 101 histopathologically confirmed testicular masses (70 malignancies, 31 benignities) were evaluated in this retrospective study. Eight hundred fifty-one radiomics features were extracted from the preoperative ADC map of each lesion. The mean and minimum ADC values are part of the radiomics features. Thirty lesions were randomly selected to estimate the reliability of the features. The redundant features were eliminated using univariate analysis (independent t test and Mann-Whitney U test, where appropriate) and Spearman's rank correlation. The least absolute shrinkage and selection operator (LASSO) algorithm was employed for feature selection and radiomics signature generation. The classification performance of the radiomics signature and minimum and mean ADC values were evaluated by receiver operating characteristic (ROC) curve analysis and compared by DeLong's test. RESULTS: The whole lesion-based mean ADC showed no difference between benign and malignant testicular masses (P = 0.070, training cohort; P = 0.418, validation cohort). Compared with the minimum ADC, the ADC-based radiomics signature yielded a higher area under the curve (AUC) in both the training (AUC: 0.904, 95% confidence interval [CI]: 0.832-0.975) and validation cohorts (AUC: 0.868, 95% CI: 0.728-1.00). CONCLUSIONS: Conventional mean ADC values are not always helpful in discriminating between testicular benignities and malignancies. The minimum ADC and radiomics signature might be better alternatives, with the radiomics signature performing better than the minimum ADC.

Difference of acute dissociation and 1-day culture on the electrophysiological properties of rat dorsal root ganglion neurons

The dissociated dorsal root ganglion (DRG) neurons with or without culture were widely used for investigation of their electrophysiological properties. The culture procedures, however, may alter the properties of these neurons and the effects are not clear. In the present study, we recorded the action potentials (AP) and the voltage-gated Na+, K+, and Ca2+ currents with patch clamp technique and measured the mRNA of Nav1.6-1.9 and Cav2.1-2.2 with real-time PCR technique from acutely dissociated and 1-day (1-d) cultured DRG neurons. The effects of the nerve growth factor (NGF) on the expression of Nav1.6-1.9 and Cav2.1-2.2 were evaluated. The neurons were classified as small (DRG-S), medium (DRG-M), and large (DRG-L), according to their size frequency distribution pattern. We found 1-d culture increased the AP size but reduced the excitability, and reduced the voltage-gated Na+ and Ca2+ currents and their corresponding mRNA expression in all types of neurons. The lack of NGF in the culture medium may contribute to the reduced Na+ and Ca2+ current, as the application of NGF recovered some of the reduced transcripts (Nav1.9, Cav2.1, and Cav2.2). 1-d culture showed neuron-type specific effects on some of the AP properties: it increased the maximum AP depolarizing rate (MDR) and hyperpolarized the resting membrane potential (RP) in DRG-M and DRG-L neurons, but slowed the maximum AP repolarizing rate (MRR) in DRG-S neurons. In conclusion, the 1-d cultured neurons had different properties with those of the acutely dissociated neurons, and lack of NGF may contribute to some of these differences

Difference of acute dissociation and 1-day culture on the electrophysiological properties of rat dorsal root ganglion neurons.

The dissociated dorsal root ganglion (DRG) neurons with or without culture were widely used for investigation of their electrophysiological properties. The culture procedures, however, may alter the properties of these neurons and the effects are not clear. In the present study, we recorded the action potentials (AP) and the voltage-gated Na+, K+, and Ca2+ currents with patch clamp technique and measured the mRNA of Nav1.6-1.9 and Cav2.1-2.2 with real-time PCR technique from acutely dissociated and 1-day (1-d) cultured DRG neurons. The effects of the nerve growth factor (NGF) on the expression of Nav1.6-1.9 and Cav2.1-2.2 were evaluated. The neurons were classified as small (DRG-S), medium (DRG-M), and large (DRG-L), according to their size frequency distribution pattern. We found 1-d culture increased the AP size but reduced the excitability, and reduced the voltage-gated Na+ and Ca2+ currents and their corresponding mRNA expression in all types of neurons. The lack of NGF in the culture medium may contribute to the reduced Na+ and Ca2+ current, as the application of NGF recovered some of the reduced transcripts (Nav1.9, Cav2.1, and Cav2.2). 1-d culture showed neuron-type specific effects on some of the AP properties: it increased the maximum AP depolarizing rate (MDR) and hyperpolarized the resting membrane potential (RP) in DRG-M and DRG-L neurons, but slowed the maximum AP repolarizing rate (MRR) in DRG-S neurons. In conclusion, the 1-d cultured neurons had different properties with those of the acutely dissociated neurons, and lack of NGF may contribute to some of these differences.