A simplified approach to discriminate between healthy subjects and patients with heart failure using cardiac magnetic resonance myocardial deformation imaging.

Aims: Left ventricular global longitudinal strain (LV-GLS) shows promise as a marker to detect early heart failure (HF). This study sought to (i) establish cardiac magnetic resonance imaging (CMR)-derived LV-GLS cut-offs to differentiate healthy from HF for both acquisition-based and post-processing techniques, (ii) assess agreement, and (iii) provide a method to convert LV-GLS between both techniques. Methods and results: A secondary analysis of a prospective study enrolling healthy subjects (n = 19) and HF patients (n = 56) was conducted. LV-GLS was measured using fast strain-encoded imaging (fSENC) and feature tracking (FT). Receiver operating characteristic (ROC) analyses were performed to derive and evaluate LV-GLS cut-offs discriminating between healthy, HF with mild deformation impairment (DI), and HF with severe DI. Linear regression and Bland-Altman analyses assessed agreement. Cut-offs discriminating between healthy and HF were identified at -19.3% and -15.1% for fSENC and FT, respectively. Cut-offs of -15.8% (fSENC) and -10.8% (FT) further distinguished mild from severe DI. No significant differences in area under ROC curve were identified between fSENC and FT. Bland-Altman analysis revealed a bias of -4.01%, 95% CI -4.42, -3.50 for FT, considering fSENC as reference. Linear regression suggested a factor of 0.76 to rescale fSENC-derived LV-GLS to FT. Using this factor on fSENC-derived cut-offs yielded rescaled FT LV-GLS cut-offs of -14.7% (healthy vs. HF) and -12% (mild vs. severe DI). Conclusion: LV-GLS distinguishes healthy from HF with high accuracy. Each measurement technique requires distinct cut-offs, but rescaling factors facilitate conversion. An FT-based LV-GLS ≥ -15% simplifies HF detection in clinical routine.

Establishment and validation of an extracellular volume model without blood sampling in ST-segment elevation myocardial infarction patients.

Aims: Recent studies have shown that extracellular volume (ECV) can also be obtained without blood sampling by the linear relationship between haematocrit (HCT) and blood pool R1 (1/T1). However, whether this relationship holds for patients with myocardial infarction is still unclear. This study established and validated an ECV model without blood sampling in ST-segment elevation myocardial infarction (STEMI) patients. Methods and results: A total of 398 STEMI patients who underwent cardiac magnetic resonance (CMR) examination with T1 mapping and venous HCT within 24 h were retrospectively analysed. All patients were randomly divided into a derivation group and a validation group. The mean CMR scan time was 3 days after primary percutaneous coronary intervention. In the derivation group, a synthetic HCT formula was obtained by the linear regression between HCT and blood pool R1 (R 2 = 0.45, P < 0.001). The formula was used in the validation group; the results showed high concordance and correlation between synthetic ECV and conventional ECV in integral (bias = -0.12; R 2 = 0.92, P < 0.001), myocardial infarction site (bias = -0.23; R 2 = 0.93, P < 0.001), and non-myocardial infarction sites (bias = -0.09; R 2 = 0.94, P < 0.001). Conclusion: In STEMI patients, synthetic ECV without blood sampling had good consistency and correlation with conventional ECV. This study might provide a convenient and accurate method to obtain the ECV from CMR to identify myocardial fibrosis.

Association between cardiac magnetic resonance ventricular strain and left ventricular thrombus in patients with ST-segment elevation myocardial infarction.

BACKGROUND: Myocardial strain can analyze early myocardial dysfunction after myocardial infarction (MI). However, the correlation between left ventricular (LV) strain (including regional and global strain) obtained by cardiac magnetic resonance (CMR) imaging and left ventricular thrombus (LVT) after ST-segment elevation myocardial infarction (STEMI) is unclear. METHODS: The retrospective clinical observation study included patients with LVT (n = 20) and non-LVT (n = 195) who underwent CMR within two weeks after STEMI. CMR images were analyzed using CVI 42 (Circle Cardiovascular Imaging, Canada) to obtain LV strain values. Logistic regression analysis identified risk factors for LVT among baseline characteristics, CMR ventricular strain, and left ventricular ejection fraction (LVEF). Considering potential correlations between strains, the ability of LV strain to identify LVT was evaluated using 9 distinct models. Receiver operating characteristic curves were generated with GraphPad Prism, and the area under the curve (AUC) of LVEF, apical longitudinal strain (LS), and circumferential strain (CS) was calculated to determine their capacity to distinguish LVT. RESULTS: Among 215 patients, 9.3% developed LVT, with a 14.5% incidence in those with anterior MI. Univariate regression indicated associations of LAD infarct-related artery, lower NT-proBNP, lower LVEF, and reduced global, midventricular, and apical strain with LVT. Further multivariable regression analysis showed that apical LS, LVEF and NT-proBNP were still independently related to LVT (Apical LS: OR = 1.14, 95%CI (1.01, 1.30), P = 0.042; LVEF: OR = 0.91, 95%CI (0.85, 0.97), P = 0.005; NT-proBNP: OR = 2.35, 95%CI (1.04, 5.31) ). CONCLUSION: Reduced apical LS on CMR is independently associated with LVT after STEMI.

Simulation and mechanism for the Ultrasound-Assisted Oiling-Out Process: A case study using Fructose-1,6-diphosphate.

Liquid-liquid separation, commonly referred to as oiling-out, frequently can occurs during crystallization, especially the anti-solvent crystallization process of phosphoryl compounds, and poses potential hurdle for high-quality product. Efficiently regulating oiling-out during crystallization remains a significant challenge. Among various techniques, ultrasound emerges as a green and effective approach to enhance the crystallization process. However, there is a dearth of in-depth research exploring the microscopic mechanisms of this process. Therefore, our research focused on the fructose-1,6-diphosphate (FDP), a typical phosphoryl compound, to gain a deeper understanding of how ultrasound influences the oiling-out process. The focused beam reflectance measurement (FBRM) technology was used to investigate the oiling-out phenomenon of FDPNa3 across various solvent ratios. In addition, the influence of ultrasound on the induction time was studied and the nucleation energy barrier was calculated. Finally, to further unravel the microscopic mechanisms, we utilized molecular simulation techniques to analyze the impact of ultrasound power on the dissolution-precipitation process. Our observations revealed a consistent oiling-out process that attainted a stable state regardless of the solvent employed. Notably, the results of the oiling-out induction time experiments indicated that ultrasound significantly reduced helped lower the nucleation energy barrier of FDP3- ions, thereby dismantling FDP3-clusters in solution. Thus, in turn, shortened the reduced induction time and promoted crystallization. Furthermore, ultrasound reduced the interactions between FDP3-ions and water molecules as well as FDP3- ions themselves. As simulated field intensity increased, these interaction forces gradually diminished, the thickness of the hydration layer surrounding the FDP3- clusters facilitating the disruption of clusters, ultimately enhancing the crystallization process.

Effect of China national centralized drug procurement policy on anticoagulation selection and hemorrhage events in patients with AF in Suining.

Background: Launched in March 2019, the National Centralized Drug Procurement (NCDP) initiative aimed to optimize the drug utilization framework in public healthcare facilities. Following the integration of Non-Vitamin K Antagonist Oral Anticoagulants (NOACs) into the procurement catalog, healthcare establishments in Suining swiftly transitioned to the widespread adoption of NOACs, beginning 1 March 2020. Objective: This study aims to comprehensively assess the impact of the NCDP policy on the efficacy of anticoagulation therapy, patient medication adherence, and the incidence of hemorrhagic events in individuals with non-valvular atrial fibrillation (NVAF) residing in Suining. The analysis seeks to elucidate the broader impacts of the NCDP policy on this patient demographic. Methods: This study analyzed patient hospitalization records from the Department of Cardiology at Suining County People's Hospital, spanning 1 January 2017, to 30 June 2022. The dataset included demographic details (age, sex), type of health insurance, year of admission, hospitalization expenses, and comprehensive information on anticoagulant therapy utilization. The CHA2DS2-VASc scoring system, an established risk assessment tool, was used to evaluate stroke risk in NVAF patients. Patients with a CHA2DS2-VASc score of 2 or higher were categorized as high-risk, while those with scores below 2 were considered medium or low-risk. Results: 1. Treatment Cost Analysis: The study included 3,986 patients diagnosed with NVAF. Following the implementation of the NCDP policy, a significant increase in the average treatment cost for hospitalized patients was observed, rising from 8,900.57 ± 9,023.02 CNY to 9,829.99 ± 10,886.87 CNY (p < 0.001). 2. Oral Anticoagulant Utilization: Overall, oral anticoagulant use increased from 40.02% to 61.33% post-NCDP (p < 0.001). Specifically, NOAC utilization among patients dramatically rose from 15.41% to 90.99% (p < 0.001). 3. Hemorrhagic Events: There was a significant decrease in hemorrhagic events following the NCDP policy, from 1.88% to 0.66% (p = 0.01). Hypertension [OR = 1.979, 95% CI (1.132, 3.462), p = 0.017], history of stroke [OR = 1.375, 95% CI (1.023, 1.847), p = 0.035], age ≥65 years [OR = 0.339, 95% CI (0.188, 0.612), p < 0.001], combination therapy of anticoagulants and antiplatelets [OR = 3.620, 95% CI (1.752, 7.480), p < 0.001], hepatic and renal insufficiency [OR = 4.294, 95% CI (2.28, 8.084), p < 0.001], and the NCDP policy [OR = 0.295, 95% CI (0.115, 0.753), p = 0.011] are significant risk factors for bleeding in patients with atrial fibrillation. 4. Re-hospitalization and Anticoagulant Use: Among the 219 patients requiring re-hospitalization, there was a notable increase in anticoagulant usage post-NCDP, from 36.07% to 59.82% (p < 0.001). NOACs, in particular, saw a substantial rise in usage among these patients, from 11.39% to 80.92% (p < 0.001). 5. Anticoagulant Type Change: The NCDP policy [OR = 28.223, 95% CI (13.148, 60.585), p < 0.001] and bleeding events [OR = 27.772, 95% CI (3.213, 240.026), p = 0.003] were significant factors influencing the alteration of anticoagulant medications in patients. Conclusion: The NCDP policy has markedly improved anticoagulation management in patients with AF. This policy has played a crucial role in enhancing medication adherence and significantly reducing the incidence of hemorrhagic events among these patients. Additionally, the NCDP policy has proven to be a key factor in guiding the selection and modification of anticoagulant therapies in the AF patient population.

Coronary Angiography-Derived Index of Microcirculatory Resistance Associated With New-Onset Atrial Fibrillation in Patients With STEMI.

BACKGROUND: Coronary angiography-derived index of microcirculatory resistance (caIMR) can effectively assess coronary microvascular dysfunction in patients with ST-segment elevation myocardial infarction (STEMI). This study aimed to explore the role of caIMR in the occurrence of new-onset atrial fibrillation (NOAF) in patients with STEMI. METHODS: This was a single-centre retrospective clinical observational study. Patients diagnosed with STEMI from September 2019 to December 2022 were included. caIMR was calculated using computational flow and pressure simulations. During admission, suspicious heart rhythm was recorded by electrocardiographic (ECG) monitoring, and NOAF was confirmed by an immediate 12-lead ECG. RESULTS: A total of 739 patients were enrolled, including 57 (7.7) with NOAF. caIMR was significantly correlated with microvascular obstruction (R = 0.604; P < 0.001) and infarct size (R = 0.514; P < 0.001). After adjusting for potential confounding factors, the results showed that caIMR (odds ratio 1.058, 95% confidence interval 1.035-1.083; P < 0.001) was an independent risk factor for NOAF in patients with STEMI. Receiver operating characteristic analysis showed that the area under the curve of caIMR for predicting NOAF was 0.716. Compared with the caIMR < 27.35 U group, the caIMR ≥ 27.35 U group had higher high-sensitivity troponin T and N-terminal pro-B-type natriuretic peptide levels. When caIMR was added to the model, the reclassification and discriminant abilities improved significantly. CONCLUSIONS: Higher caIMR was an independent risk factor for NOAF in patients with STEMI. The caIMR had high specificity and sensitivity for predicting NOAF in patients with STEMI. The integration of caIMR into clinical risk factors showed significantly increased predictability for NOAF in patients with STEMI.

Half-Dose versus Single-Dose Gadobutrol for Extracellular Volume Measurements in Cardiac Magnetic Resonance.

BACKGROUND: Cardiac magnetic resonance (CMR) imaging with gadolinium-based contrast agents offers unique non-invasive insights into cardiac tissue composition. Myocardial extracellular volume (ECV) has evolved as an objective and robust parameter with broad diagnostic and prognostic implications. For the gadolinium compound gadobutrol, the recommended dose for cardiac imaging, including ECV measurements, is 0.1 mmol/kg (single dose). This dose was optimized for late enhancement imaging, a measure of focal fibrosis. Whether a lower dose is sufficient for ECV measurements is unknown. We aim to evaluate the accuracy of ECV measurements using a half dose of 0.05 mmol/kg gadobutrol compared to the standard single dose of 0.1 mmol/kg. METHODS AND RESULTS: From a contemporary trial (NCT04747366, registered 10 February 2021), a total of 25 examinations with available T1 mapping before and after 0.05 and 0.1 mmol/kg gadobutrol were analyzed. ECV values were calculated automatically from pre- and post-contrast T1 relaxation times. T1 and ECV Measurements were performed in the midventricular septum. ECV values after 0.05 and 0.1 mmol/kg gadobutrol were correlated (R2 = 0.920, p < 0.001). ECV values after 0.05 mmol/kg had a bias of +0.9% (95%-CI [0.4; 1.4], p = 0.002) compared to 0.1 mmol/kg gadobutrol, with limits of agreement from -1.5 to 3.3%. CONCLUSIONS: CMR with a half dose of 0.05 mmol/kg gadobutrol overestimated ECV by 0.9% compared with a full dose of 0.1 mmol/kg, necessitating adjustment of normal values when using half-dose ECV imaging.

Cardiac MRI Left Atrial Strain Associated With New-Onset Atrial Fibrillation in Patients With ST-Segment Elevation Myocardial Infarction.

BACKGROUND: Left atrial (LA) strain is associated with structural remodeling of the LA. Whether there is an association between LA strain obtained by cardiac magnetic resonance imaging (MRI) and new-onset atrial fibrillation (AF) after ST-segment elevation myocardial infarction (STEMI) is unclear. PURPOSE: To investigate the relationship between LA strain and new-onset AF after STEMI. STUDY TYPE: Retrospective. POPULATION: Three hundred and seventy-nine STEMI patients were enrolled, of which 26 had new-onset AF. FIELD STRENGTH/SEQUENCE: 3.0 T, balanced turbo field echo sequence. ASSESSMENT: Patients were divided into w/o AF group and new-onset AF group. Cardiac MRI images were analyzed using cardiovascular imaging software CVI 42 (Circle Cardiovascular Imaging, Canada). An automatic tracing algorithm was applied to obtain strain values. The reservoir strain, conduit strain, and booster strain were included in model 1, model 2, and model 3, respectively. STATISTICAL TESTS: Student's t-test, Mann-Whiney U test, and chi-square test were performed. Variables with a P ≤ 0.05 were incorporated into the logistic regression analysis. Area under curve of receiver operating characteristic was used to assess the ability of LA strain to identify new-onset AF. Bayesian information criterion, Akaike information criterion, and C-index were used to make comparisons between three models. P < 0.05 was considered statistically significant. RESULTS: Three models were used to assess LA strain identification ability for new-onset AF. After including multiple factors, right coronary artery (RCA), LVEF, and reservoir strain were still risk factors for new-onset AF in model 1. In model 2, age, RCA, LVEF, and conduit strain were still risk factors for new-onset AF. In model 3, RCA, LVEF, LVEDVi, and booster strain were still risk factors for new-onset AF. Model 2 has a stronger identification ability than others. DATA CONCLUSION: LA strain associated with new-onset AF after STEMI. The model including conduit strain was the best-fit one. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 3.

Quantification of myocardial extracellular volume without blood sampling.

Aims: Cardiac magnetic resonance (CMR) T1 relaxation time mapping is an established technique primarily used to identify diffuse interstitial fibrosis and oedema. The myocardial extracellular volume (ECV) can be calculated from pre- and post-contrast T1 relaxation times and is a reproducible parametric index of the proportion of volume occupied by non-cardiomyocyte components in myocardial tissue. The conventional calculation of the ECV requires blood sampling to measure the haematocrit (HCT). Given the high variability of the HCT, the blood collection is recommended within 24 h of the CMR scan, limiting its applicability and posing a barrier to the clinical routine use of ECV measurements. In recent years, several research groups have proposed a method to determine the ECV by CMR without blood sampling. This is based on the inverse relationship between the T1 relaxation rate (R1) of blood and the HCT. Consequently, a 'synthetic' HCT could be estimated from the native blood R1, avoiding blood sampling. Methods and results: We performed a review and meta-analysis of published studies on synthetic ECV, as well as a secondary analysis of previously published data to examine the effect of the chosen regression modell on bias. While, overall, a good correlation and little bias between synthetic and conventional ECV were found in these studies, questions regarding its accuracy remain. Conclusion: Synthetic HCT and ECV can provide a 'non-invasive' quantitative measurement of the myocardium's extracellular space when timely HCT measurements are not available and large alterations in ECV are expected, such as in cardiac amyloidosis. Due to the dependency of T1 relaxation times on the local setup, calculation of local formulas using linear regression is recommended, which can be easily performed using available data.

Left atrial epicardial adipose tissue is associated with low voltage zones in the left atrium in patients with non-valvular atrial fibrillation.

Objective: Epicardial adipose tissue (EAT) is related to atrial fibrillation (AF), but the specific mechanism is still unclear. Left atrial (LA) low voltage zones (LVZ) can well reflect atrial fibrosis. This study investigated the relationship between EAT and LVZ in non-valvular AF (NVAF) patients. Methods: This observational study including patients with NVAF (n = 214) undergoing radiofrequency ablation (RFCA) for the first time in our hospital and 62 matched controls. The EAT volume and attenuation were measured by contrast-enhanced computed tomography. A three-dimensional mapping system was used to map the left atrial endocardium and evaluate LA-LVZ. Patients were divided into LVZ and non-LVZ groups according to the presence or absence of LVZ. Results: Patients with AF showed higher LA-EAT volume and lower attenuation value than controls (29.7 ± 11.2 cm3 vs. 20.9 ± 8.6 cm3, P = 0.021; -91.2 ± 5.6 HU vs. -88.7 ± 5.9 HU, P < 0.001). Compared with the group without LVZ, there were significant differences in age [65 (59-71) vs. 60 (52-69), P = 0.006], LAVI [75.1 ± 20.7 ml/m2 vs. 67.2 ± 20.9 ml/m2, P = 0.018], LA-EAT volume (34.8 ± 11.5 cm3 vs. 28.1 ± 10.6 cm3, P < 0.001) and LA-EAT attenuation (-93.9 ± 5.3 HU vs. -90.4 ± 5.5 HU, P < 0.001). Multivariate regression analysis showed that age (OR = 1.040; 95%CI: 1.001-1.078, P = 0.042), LAVI (OR = 1.019; 95%CI: 1.002-1.037, P = 0.032), LA-EAT volume (OR = 1.193; 95%CI: 1.015-1.402, P = 0.034) and attenuation value (OR = 0.801; 95%CI: 0.701-0.916 P = 0.001) were independent predictors of LVZ. After LA-EAT attenuation was incorporated into the clinical model, the comprehensive discrimination and net reclassification tended to improve (IDI and NRI > 0, P < 0.05). Conclusion: LA-EAT volume and attenuation values can independently predict the presence of LVZ, and LA-EAT attenuation has a better predictive value than LA-EAT volume.

Association of Soluble Suppression of Tumorigenicity 2 with New-Onset Atrial Fibrillation in Acute Myocardial Infarction.

BACKGROUND: The combination of acute myocardial infarction (AMI) and atrial fibrillation (AF) is still a thorny problem in the clinic. At present, there are few reports on the role of soluble suppression of tumorigenicity 2 (sST2) in AF after AMI. This study was to explore the predictive value of sST2 in patients with AMI for new-onset AF. METHODS: This is a single-center retrospective clinical observation study. We continuously included AMI patients from September 2019 to November 2021. The concentration of sST2 in blood samples was determined. During admission, a suspicious heart rhythm was recorded by electrocardiogram (ECG) monitoring, and new-onset AF was confirmed by immediate body surface ECG. RESULTS: After multiple factors were included, age, right coronary artery, high-sensitivity C-reactive protein, left ventricular ejection fraction, and sST2 were still risk factors for new-onset AF. The area under curve value of age and sST2 was more than 0.7, which showed good diagnostic value. For reevaluation, the sST2 was added to the clinical new-onset AF prediction model. It was found that the integrated discrimination improvement and net reclassification index in the model were improved significantly. CONCLUSION: sST2 is an independent predictor of new-onset AF in patients with AMI and can improve the accuracy of the AF risk model.

Synthetic Extracellular Volume in Cardiac Magnetic Resonance Without Blood Sampling: a Reliable Tool to Replace Conventional Extracellular Volume.

BACKGROUND: The calculation of extracellular volume (ECV) in cardiac magnetic resonance requires hematocrit, limiting its applicability in clinical practice. Based on the linear relationship between hematocrit and blood T1 relaxivity, a synthetic ECV could be estimated without a blood sample. We aim to develop and test regression models for synthetic ECV without blood sampling in 1.5-T and 3.0-T scanners. METHODS: A total of 1101 subjects who underwent cardiac magnetic resonance scanning with native and postcontrast T1 mapping and venous hematocrit within 24 hours were retrospectively enrolled. Subjects were randomly split into derivation (n=550) and validation (n=551) subgroups for each scanner. Different regression models were derived controlling for sex, field strength, and left ventricle/right ventricle blood pool and validated in the validation group. We performed additional validation analyses in subgroups of patients with histological validation (n=17), amyloidosis (n=29), anemia (n=185), and reduced ejection fraction (n=322). RESULTS: In the derivation group, 8 specific models and 2 common estimate models were derived. In the validation group, using specific models, synthetic ECV had high agreement with conventional ECV (R2, 0.87; P<0.0001 and R2, 0.88, P<0.0001; -0.16% and -0.10%, left ventricle and right ventricle model, respectively). Common models also performed well (R2, 0.88; P<0.0001 and R2, 0.89, P<0.0001; -0.21% and -0.18%, left ventricle and right ventricle model, respectively). Histological validation demonstrated equal performance of synthetic and measured ECV. Synthetic ECV as calculated by the common model showed a bias in the anemia cohort significantly reduced by the specific model (-2.45 to -1.28, right ventricle common and specific model, respectively). CONCLUSIONS: Synthetic ECV provided a promising way to calculate ECV without blood sampling. Specific models could provide the most accurate value, while common models could be more suitable in routine clinical practice because of their simplicity while maintaining adequate accuracy.

Gene cloning of a highly active phytase from Lactobacillus plantarum and further improving its catalytic activity and thermostability through protein engineering.

Phytase belongs to orthophosphate monoester hydrolase, which can catalyze the gradual hydrolysis of phytic acid to inositol phosphate. It can be added to animal feed to reduce the anti-nutritional factor of phytic acid in feed. The thermostability and specific activity of phytases are two key factors determining their potential applications. In this study, a highly active 233-aa phytase gene (LpPHY233) from Lactobacillus plantarum was cloned and expressed in Escherichia coli (E. coli), achieving 800 times higher activity than that expressed in L. plantarum. Next, the temperature characteristic and catalytic performance of LpPHY233 was improved by disulfide bond engineering and C-terminal truncation, respectively. Surprisingly, the specific activity of the C-terminal truncated mutant LpPHY200 was about 5.6 times higher than that of LpPHY233, and the optimal temperature for the mutant LpPHY233S58C/K61C introduced disulfide bond was 15 °C higher than that of LpPHY233. Moreover, these phytase mutants displayed excellent pH property and kinetic parameters, and have great application prospect in feed additives field. The molecular basis for its catalytic performance was preliminarily explained by in silico design methods. Our results provided a solid theoretical foundation for further molecular modification and industrial application of phytases.

Left atrial appendage orifice area and morphology is closely associated with flow velocity in patients with nonvalvular atrial fibrillation.

BACKGROUND: Thromboembolic events are the most serious complication of atrial fibrillation (AF), and the left atrial appendage (LAA) is the most important site of thrombosis in patients with AF. During the period of COVID-19, a non-invasive left atrial appendage detection method is particularly important in order to reduce the exposure of the virus. This study used CT three-dimensional reconstruction methods to explore the relationship between LAA morphology, LAA orifice area and its mechanical function in patients with non-valvular atrial fibrillation (NVAF). METHODS: A total of 81 consecutive patients with NVAF (36 cases of paroxysmal atrial fibrillation and 45 cases of persistent atrial fibrillation) who were planned to undergo catheter radiofrequency ablation were enrolled. All patients were examined by transthoracic echocardiography (TTE), TEE, and computed tomography angiography (CTA) before surgery. The LAA orifice area was obtained according to the images of CTA. According to the left atrial appendage morphology, it was divided into chicken wing type and non-chicken wing type. At the same time, TEE was performed to determine left atrial appendage flow velocity (LAAFV), and the relationship between the left atrial appendage orifice area and LAAFV was analyzed. RESULTS: The LAAFV in Non-chicken wing group was lower than that in Chicken wing group (36.2 ± 15.0 cm/s vs. 49.1 ± 22.0 cm/s, p-value < 0.05). In the subgroup analysis, the LAAFV in Non-chicken wing group was lower than that in Chicken wing group in the paroxysmal AF (44.0 ± 14.3 cm/s vs. 60.2 ± 22.8 cm/s, p-value < 0.05). In the persistent AF, similar results were observed (29.7 ± 12.4 cm/s vs. 40.8 ± 17.7 cm/s, p-value < 0.05). The LAAFV in persistent AF group was lower than that in paroxysmal AF group (34.6 ± 15.8 cm/s vs. 49.9 ± 20.0 cm/s, p-value < 0.001). The LAAFV was negatively correlated with left atrial dimension (R = - 0.451, p-value < 0.001), LAA orifice area (R= - 0.438, p-value < 0.001) and left ventricular mass index (LVMI) (R= - 0.624, p-value < 0.001), while it was positively correlated with LVEF (R = 0.271, p-value = 0.014). Multiple linear regression analysis showed that LAA morphology (ß = - 0.335, p-value < 0.001), LAA orifice area (ß = - 0.185, p-value = 0.033), AF type (ß = - 0.167, p-value = 0.043) and LVMI (ß = - 0.465, p-value < 0.001) were independent factors of LAAFV. CONCLUSIONS: The LAA orifice area is closely related to the mechanical function of the LAA in patients with NVAF. The larger LAA orifice area and LVMI, Non-chicken wing LAA and persistent AF are independent predictors of decreased mechanical function of LAA, and these parameters might be helpful for better management of LA thrombosis.

Ring-like late gadolinium enhancement for predicting ventricular tachyarrhythmias in non-ischaemic dilated cardiomyopathy.

AIMS: Myocardial fibrosis is associated with clinical ventricular tachyarrhythmia (VTA) events in patients with non-ischaemic dilated cardiomyopathy (DCM). Subepicardial or mid-wall ring-like late gadolinium enhancement (LGE) has received increasing attention in recent years. The aim of this study was to investigate the relationship between ring-like LGE and VTAs in DCM. METHODS AND RESULTS: Patients diagnosed with non-ischaemic DCM who underwent cardiac magnetic resonance with LGE imaging at baseline were investigated. The composite outcome was the occurrence of VTAs defined as sustained ventricular tachycardia, ventricular fibrillation/flutter, aborted sudden cardiac death (SCD), SCD, and appropriate implantable cardioverter-defibrillator intervention. The final cohort comprised 157 patients, including 36 (22.9%) in no LGE group, 48 (30.6%) in focal LGE group, 40 (25.5%) in multi-focal LGE group, and 33 (21%) in ring-like LGE group. Ring-like LGE group patients were younger compared to focal and multi-focal LGE group (P < 0.001) with higher left ventricular ejection fraction (33.0% vs. 24.4% vs. 22.1%, P < 0.001). After a median of 13 ± 7 months follow-up, compared to patients with no LGE, the hazard ratios (HRs) with 95% confidence intervals (CIs) for VTAs were 2.90 (0.56-15.06), 5.55 (1.21-25.44), and 11.75 (2.66-51.92) for patients with focal LGE, multi-focal LGE, and ring-like LGE, respectively. After multivariable adjustment, ring-like LGE group remained associated with increased risk of VTAs (adjusted HR 10.00, 95% CI 1.54-64.98; P = 0.016) independent of the global LGE burden. CONCLUSION: The ring-like pattern of LGE is independently associated with an increased risk of VTAs in patients with non-ischaemic DCM.

Impact of Wideband Late Gadolinium Enhancement Cardiac Magnetic Resonance Imaging on Device-Related Artifacts in Different Implantable Cardioverter-Defibrillator Types.

BACKGROUND: Late gadolinium enhancement (LGE) imaging in patients with implantable cardioverter-defibrillators (ICD) is limited by device-related artifacts (DRA). The use of wideband (WB) LGE protocols improves LGE images, but their efficacy with different ICD types is not well known. PURPOSE: To assess the effects of WB LGE imaging on DRA in different non-MR conditional ICD subtypes. STUDY TYPE: Retrospective. POPULATION: A total of 113 patients undergoing cardiac magnetic resonance imaging with three ICD subtypes: transvenous (TV-ICD, N = 48), cardiac-resynchronization therapy device (CRT-D, N = 48), and subcutaneous (S-ICD, N = 17). FIELD STRENGTH/SEQUENCE: 5 T scanner, standard LGE, and WB LGE imaging with a phase-sensitive inversion recovery segmented gradient echo sequence. ASSESSMENT: DRA burden was defined as the number of artifact-positive short-axis LGE slices as percentage of the total number of short-axis slices covering the left ventricle from based to apex, and was determined for WB and standard LGE studies for each patient. Additionally, artifact area on each slice was quantified. STATISTICAL TESTS: Shapiro-Wilks, Kruskal-Wallis analysis of variance, Dunn tests with Bonferroni correction, and Mann-Whitney U-test. RESULTS: In patients with TV-ICD, DRA burden was significantly reduced and nearly eliminated with WB LGE compared to standard LGE imaging (median [interquartile range]: 0 [0-7]% vs. 18 [0-50]%, P < 0.05), but WB imaging had less of an impact on DRA in the CRT-D (8 [0-23]% vs. 16 [0-45]%, p = 0.12) and S-ICD (60 [15-71]% vs. 67 [50-92]%, P = 0.09) patients. Residual DRA was significantly greater (P < 0.05) for S-ICD compared to other device types with WB LGE imaging, despite the generators of all three ICD types having similar proximity to the heart. The area of S-ICD associated DRA was smaller with WB LGE (P < 0.001) than with standard LGE imaging and the artifacts had different characteristics (dark signal void instead of a bright hyperenhancement artifact). DATA CONCLUSION: Although WB LGE imaging reduced the burden of DRA caused by S-ICD, the residual artifact was greater than that observed with TV-ICD and CRT-D devices. Further developments are needed to better resolve S-ICD artifacts. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: STAGE: 5.

MicroRNA-214-5p protects against myocardial ischemia reperfusion injury through targeting the FAS ligand.

INTRODUCTION: MicroRNAs (miRNAs) are considered as crucial modulators in myocardial ischemia and reperfusion (I/R) injury. The present study aimed to investigate the expression and biological functions of miR-214-5p via targeting Fas ligand (FASLG) in I/R injury. MATERIAL AND METHODS: Lactate dehydrogenase, casein kinase, malondialdehyde assay, reactive oxygen species (ROS) detection and cell apoptosis analysis measured cell damage and cell apoptosis in H9c2 cells under hypoxia/reperfusion (H/R) treatment. Bioinformatics and dual luciferase reporter assays demonstrated the molecular mechanism of miR-214-5p in cardiac cells. 2,3,5-Triphenyltetrazolium chloride (TTC) staining, hematoxylin-eosin (HE) staining and adenovirus injection were performed in I/R treated mice. RESULTS: The expression of miR-214-5p was decreased in H/R injured H9c2 cells compared with control cells (p < 0.001). Overexpression of miR-214-5p reduced cell damage and apoptosis in H9c2 cells under H/R treatment (p < 0.001). Further study revealed that FASLG was a target of miR-214-5p. Enhanced expression of FASLG attenuated the protective function of miR-214-5p in H9c2 cells subjected to H/R injury (P < 0.001). Moreover, the elevated expression of miR-214-5p by adenovirus injection protected cardiac cells from I/R injury in mice (n = 6/per group). CONCLUSIONS: We found that miR-214-5p exerted a protective role in I/R injured cardiac cells by direct targeting FASLG in vitro and in vivo.

SNHG1 Inhibits ox-LDL-Induced Inflammatory Response and Apoptosis of HUVECs via Up-Regulating GNAI2 and PCBP1.

Dysfunction of human endothelial cells is an important trigger for atherosclerosis. Oxidative low-density lipoprotein (ox-LDL) usually was used to stimulate the dysfunction of human umbilical vein endothelial cells (HUVECs). LncRNA SNHG1 (small nucleolar RNA host gene 1) is a cerebral infarction-associated gene. The present study was designed to investigate the role of SNHG1 in ox-LDL-induced HUVECs. Cell viability was evaluated by CCK-8 and MTT assay. Cell apoptosis was detected by flow cytometry analysis. Cell inflammatory response was evaluated by detecting LDH, IL-6, IL-1ß levels. The results revealed that up-regulation of SNHG1 attenuated ox-LDL-induced cell injury and inflammatory response in HUVECs. Next, mechanism assays including RNA immunoprecipitation (RIP) assay, luciferase reporter assay, and RNA pull-down assay, helped us to identify the interaction between miR-556-5 and SNHG1. GNAI2 (G protein subunit alpha i2) and PCBP1 (poly(rC) binding protein 1) were identified as the downstream targets of miR-556-5p. SNHG1 regulated dysfunctions of ox-LDL-induced HUVECs via sponging miR-556-5p and up-regulating GNAI2 and PCBP1. SNHG1 attenuated cell injury and inflammatory response in ox-LDL-induced HUVECs via up-regulating both GNAI2 and PCBP1 at a miR-556-5p dependent way.