Cardiac T1ρ Mapping Values Affected by Age and Sex in a Healthy Chinese Cohort.

BACKGROUND: To facilitate the clinical use of cardiac T1ρ, it is important to understand the impact of age and sex on T1ρ values of the myocardium. PURPOSE: To investigate the impact of age and gender on myocardial T1ρ values. STUDY TYPE: Cross-sectional. POPULATION: Two hundred ten healthy Han Chinese volunteers without cardiovascular risk factors (85 males, mean age 34.4 ± 12.5 years; 125 females, mean age 37.9 ± 14.8 years). FIELD STRENGTH/SEQUENCE: 1.5 T; T1ρ-prepared steady-state free precession (T1ρ mapping) sequence. ASSESSMENT: Basal, mid, and apical short-axis left ventricular T1ρ maps were acquired. T1ρ maps acquired with spin-lock frequencies of 5 and 400 Hz were subtracted to create a myocardial fibrosis index (mFI) map. T1ρ and mFI values across different age decades, sex, and slice locations were compared. STATISTICAL TESTS: Shapiro-Wilk test, Student's t test, Mann-Whitney U test, linear regression analysis, one-way analysis of variance and intraclass correlation coefficient. SIGNIFICANCE: P value <0.05. RESULTS: Women had significantly higher T1ρ and mFI values than men (50.3 ± 2.0 msec vs. 47.7 ± 2.4 msec and 4.7 ± 1.0 msec vs. 4.3 ± 1.1 msec, respectively). Additionally, in males and females combined, there was a significant positive but weak correlation between T1ρ values and age (r = 0.27), while no correlation was observed between the mFI values and age (P = 0.969). DATA CONCLUSION: We report potential reference values for cardiac T1ρ by sex, age distribution, and slice location in a Chinese population. T1ρ was significantly correlated with age and sex, while mFI was only associated with sex. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.

The Association of Epicardial Adipose Tissue Volume and Atrial Fibrillation in Patients With Hypertrophic Cardiomyopathy: As Assessed by Cardiac MR.

BACKGROUND: Epicardial adipose tissue (EAT) is a metabolically active visceral fat linked to cardiovascular disease. Prior studies demonstrated the predictive value of EAT volume (EATV) in atrial fibrillation (AF) among hypertrophic obstructive cardiomyopathy patients. PURPOSE: To investigate the association between EATV and AF in hypertrophic cardiomyopathy (HCM). STUDY TYPE: Retrospective. POPULATION: Two hundred and twenty-four HCM patients (including 79 patients with AF and 145 patients without AF, 154 men) and 80 healthy controls (54 men). FIELD STRENGTH/SEQUENCE: 3.0 T scanner; balanced steady-state free precession (SSFP) cine sequence, gradient echo. ASSESSMENT: EAT thickness was assessed in the 4-chamber and basal short-axis planes. EAT volume was calculated by outlining the epicardial border and visceral pericardium layer on short-axis cine images. STATISTICAL TESTS: Shapiro-Wilk test, Student's t test or the Mann-Whitney U test, chi-square test or Fisher's exact test, Multivariate linear regression analyses, Multivariable binary logistic regression analysis. Intraclass correlation coefficient. Significance was determined at P < 0.05. RESULTS: EATV and EAT volume index (EATVI) were significantly greater in HCM patients with AF than those without AF (126.6 ± 25.9 mL vs. 90.5 ± 24.5 mL, and 73.0 ± 15.9 mL/m2 vs. 51.3 ± 13.4 mL/m2). EATVI was associated with AF in multivariable linear regression analysis among HCM patients (ß = 0.62). Multivariable logistic regression analysis revealed that compared to other indicators, the area under curve (AUC) of EATVI was 0.86 (cut-off, 53.9 mL/m2, 95% CI, 0.80-0.89), provided a better performance, with the sensitivity of 96.2% and specificity of 58.6%. The combined model exhibited superior association with AF presence compared to the clinical model (AUC 0.96 vs. 0.76) and the imaging model (AUC 0.96 vs. 0.93). DATA CONCLUSION: EATVI was associated with AF. EATVI was significantly correlated with incident AF, and provided a better performance in HCM patients compared to other indicators. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

Deleterious effect in endothelin receptor-mediated coronary artery smooth muscle contractility in high-salt diet rats.

BACKGROUND AND AIMS: High-salt diet has been suggested to increase the risk of heart disease. However, the mechanisms underlying coronary artery tension dysfunction caused by high-salt diet are unclear. Previous studies have shown that coronary artery spasm is often induced by endothelin-1 (ET-1) and thromboxane, leading to myocardial ischemia, while the store-operated Ca2+ entry (SOCE) function of coronary smooth muscle is very important in this process. METHODS AND RESULTS: Tension measurements of endothelium-denuded coronary artery ring segments showed that vasocontraction induced by U46619, ET-1, orSTIM1/Orai1-mediated SOCE was significantly lower in 4% high-salt diet rats than in control rats fed a regular diet. The results of western blotting and immunohistochemistry assays showed lower expression levels of endothelial receptors ETA and ETB, STIM1 and Orai1 in coronary artery of high-salt intake rats compared with control rats. Fibrosis was observed by using Masson's trichrome staining and picrosirius red staining. The plasma ET-1 concentration in high-salt diet rats was significantly higher than that of controls. The interventricular septum and posterior wall of high-salt diet rats were significantly thickened. CONCLUSION: Our findings indicated that coronary artery tension was significantly decreased in 4% high-salt diet rats and that this decrease may be due to the change of endothelin receptor and its downstream pathway SOCE related protein expression in coronary artery. Coronary fibrosis was observed in rats fed with high-salt diet. This study provides potential mechanistic insights into high-salt intake-induced heart disease.

Myocardial involvement characteristics by cardiac MR imaging in neurological and non-neurological Wilson disease patients.

OBJECTIVES: To explore the characteristics of myocardial involvement in Wilson Disease (WD) patients by cardiac magnetic resonance (CMR). METHODS: We prospectively included WD patients and age- and sex-matched healthy population. We applied CMR to analyze cardiac function, strain, T1 maps, T2 maps, extracellular volume fraction (ECV) maps, and LGE images. Subgroup analyzes were performed for patients with WD with predominantly neurologic manifestations (WD-neuro +) or only hepatic manifestations (WD-neuro -). RESULTS: Forty-one WD patients (age 27.9 ± 8.0 years) and 40 healthy controls (age 25.4 ± 2.9 years) were included in this study. Compared to controls, the T1, T2, and ECV values were significantly increased in the WD group (T1 1085.1 ± 39.1 vs. 1046.5 ± 33.1 ms, T2 54.2 ± 3.3 ms vs. 51.5 ± 2.6 ms, ECV 31.8 ± 3.6% vs. 24.3 ± 3.7%) (all p < 0.001). LGE analysis revealed that LGE in WD patients was predominantly localized to the right ventricular insertion point and interventricular septum. Furthermore, the WD-neuro + group showed more severe myocardial damage compared to WD-neuro - group. The Unified Wilson Disease Rating Scale score was significantly correlated with ECV (Pearson's r = 0.64, p < 0.001). CONCLUSIONS: CMR could detect early myocardial involvement in WD patients without overt cardiac function dysfunction. Furthermore, characteristics of myocardial involvement were different between WD-neuro + and WD-neuro - , and myocardial involvement might be more severe in WD-neuro + patients. CRITICAL RELEVANCE STATEMENT: Cardiac magnetic resonance enables early detection of myocardial involvement in Wilson disease patients, contributing to the understanding of distinct myocardial characteristics in different subgroups and potentially aiding in the assessment of disease severity. KEY POINTS: • CMR detects WD myocardial involvement with increased T1, T2, ECV. • WD-neuro + patients show more severe myocardial damage and correlation with ECV. • Differences of myocardial characteristics exist between WD-neuro + and WD-neuro - patients.

The Efficacy and Safety of Bivalirudin Versus Heparin in the Anticoagulation Therapy of Extracorporeal Membrane Oxygenation: A Systematic Review and Meta-Analysis.

Background: Bivalirudin is a direct thrombin inhibitor (DTI) that can be an alternative to unfractionated heparin (UFH). The efficacy and safety of bivalirudin in anticoagulation therapy in extracorporeal membrane oxygenation (ECMO) remain unknown. Methods: This study followed the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. A systematic literature search was performed in PubMed, EMBASE, and The Cochrane Library databases to identify all relevant original studies estimating bivalirudin's efficacy and safety versus UFH as anticoagulation therapy in ECMO. The time limit for searching is from the search beginning to June 2021. Two researchers independently screened the literature, extracted data and evaluated the risk of bias of the included studies. The meta-analysis (CRD42020214713) was performed via the RevMan version 5.3.5 Software and STATA version 15.1 Software. Results: Ten articles with 847 patients were included for the quantitative analysis. Bivalirudin can significantly reduce the incidence of major bleeding in children (I 2 = 48%, p = 0.01, odd ratio (OR) = 0.17, 95% confidence interval (CI): 0.04-0.66), patient thrombosis (I 2 = 0%, p = 0.02, OR = 0.58, 95% CI: 0.37-0.93), in-circuit thrombosis/interventions (I 2 = 0%, p = 0.0005, OR = 0.40, 95% CI: 0.24-0.68), and in-hospital mortality (I 2 = 0%, p = 0.007, OR = 0.64, 95% CI: 0.46-0.88). Also, comparable clinical outcomes were observed in the incidence of major bleeding in adults (I 2 = 48%, p = 0.65, OR = 0.87, 95% CI: 0.46-1.62), 30-day mortality (I 2 = 0%, p = 0.61, OR = 0.83, 95% CI: 0.41-1.68), and ECMO duration in adults (I 2 = 41%, p = 0.75, mean difference (MD) = -3.19, 95% CI: -23.01-16.63) and children (I 2 = 76%, p = 0.65, MD = 40.33, 95% CI:-135.45-216.12). Conclusions: Compared with UFH, bivalirudin can be a safe and feasible alternative anticoagulant option to UFH as anticoagulation therapy in ECMO, especially for heparin resistance (HR) and heparin-induced thrombocytopenia (HIT) cases.

Association of the P441L KCNQ1 variant with severity of long QT syndrome and risk of cardiac events.

Dysfunction of potassium voltage-gated channel subfamily Q member 1 (KCNQ1) is a primary cause of long QT syndrome type 1 (LQT1). Here, we report a missense mutation P441L in KCNQ1 C-terminus of a 37-year-old woman with severe LQT1 phenotype. Variant P441L transporting to the plasma membrane and interacting with KCNE1 were both markedly decreased, leading to potassium efflux disorder and eventually LQT1. Mutations between the C-terminal helix A and helix B of KCNQ1 have linked with low cardiac event risk, however, we firstly find variant P441L causing a severe LQT1 phenotype with a high risk of cardiac events.

LBP Protects Hepatocyte Mitochondrial Function Via the PPAR-CYP4A2 Signaling Pathway in a Rat Sepsis Model.

OBJECTIVES: To explore the role of LPS binding protein (LBP) in metabolism and optimize sepsis treatment. DESIGN: A sepsis model was established by injecting LPS into LBP-/- rats and WT rats and observing changes in the liver over time (0, 1, 6, and 24 h). SETTING: Detecting liver inflammation and injury. Optimizing the treatment of sepsis. SUBJECTS: WT rats and LBP-/- rats. INTERVENTIONS: We established a sepsis model by injecting LPS intravenously. MEASUREMENTS AND MAIN RESULTS: First, we induced sepsis in WT and LBP-/- rats with LPS. The rats were sacrificed, and serum and liver samples were collected at 1, 6, and 24 h after LPS injection. We found that the deletion of LBP reduced LPS-induced liver inflammation and injury at 1 and 6 h. Ballooning degeneration was clearly present in LBP-/- rat livers at 24 h after LPS injection. We found that mitochondrial damage and reactive oxygen species (ROS) levels were higher in LBP-/- rat livers than in WT rat livers at 24 h after LPS injection. According to the transcriptomic results, the peroxisome proliferator-activated receptor (PPAR) pathway may be the reason for lesions in LBP-/- rats. To further investigate the function of PPARα in sepsis, we inhibited mTOR with rapamycin and examined mitochondrial injury and ROS levels. The levels of mitochondrial damage and ROS were reduced after LBP-/- rats were pretreated with rapamycin in the context of LPS-induced sepsis. Inhibiting CYP4a2, one of the PPARα-target gene products, reduced the level of LPS-induced ROS in LBP-/- rats. CONCLUSION: LBP protects hepatic mitochondria against LPS-induced damage via the LBP-PPARα-CYP4a2 signaling pathway.