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A new species, Neottia wuyishanensis (Neottieae, Orchidaceae), is described and illustrated from Wuyishan, Fujian, eastern China, based on morphological characters and molecular data. Molecular phylogenetics indicate that N. wuyishanensis is nested within the clade formed by Neottia fugongensis and Neottia nujiangensis. Morphologically, N. wuyishanensis is similar to N. fugongensis and N. pseudonipponica, but differs from them by having indistinct auricles at the base, and in the shape and size of lobelets.

To explore myocardial iron content using Cardiac T2* Mapping in dialysis patients undergoing oral iron therapy or intravenous iron supplements compared to healthy controls.Fifty-nine dialysis patients, including 30 peritoneal dialysis (PD) patients who underwent oral iron therapy, 29 hemodialysis (HD) dialysis patients who underwent intravenous iron supplements, and 30 healthy controls were included in the study. Cardiac MRI, including cine, T2 stir, and T2* mapping, was conducted at 3.0T. Quantitive T2* mapping, Cine imaging analysis was performed by two radiologists using cvi42.The global cardiac T2* value was higher in dialysis patients than in healthy controls (27.1 ± 6.29 ms versus 24.6 ± 3.60 ms, p0.05). The global cardiac T2* value of PD patients was higher than that of HD patients (28.5 ± 4.30 ms versus 25.x7 ± 3.54 ms, p0.05). The anteroseptal cardiac T2* value was higher in PD patients than in healthy controls (32.0 ± 4.49 ms versus 27.8 ± 4.02 ms, p0.05). The global T2* value negatively correlated with left ventricular ejection fraction (LVEF), peak radial strain, circumferential strain, and longitudinal strain.Our study confirmed that PD patients have myocardial iron deficiency despite undergoing oral iron therapy compared to HD patients who received intravenous iron treatments. And the Cardiac T2* value was found to be an independent risk factor and predictor of LVEF and left ventricular altered mechanics. Intravenous iron supplements may be an effective cardiac iron management strategy in patients with HD-dependent end-stage renal disease.

BACKGROUND: Noncontrast cardiac T1 times are increased in dialysis patients which might indicate fibrotic alterations in uremic cardiomyopathy. PURPOSE: To explore the application of the texture analysis (TA) of T1 images in the assessment of myocardial alterations in dialysis patients. STUDY TYPE: Case-control study. POPULATION: A total of 117 subjects, including 22 on hemodialysis, 44 on peritoneal dialysis, and 51 healthy controls. FIELD STRENGTH: A 3 T, steady-state free precession (SSFP) sequence, modified Look-Locker imaging (MOLLI). ASSESSMENT: Two independent, blinded researchers manually delineated endocardial and epicardial borders of the left ventricle (LV) on midventricular T1 maps for TA. STATISTICAL TESTS: Texture feature selection was performed, incorporating reproducibility verification, machine learning, and collinearity analysis. Multivariate linear regressions were performed to examine the independent associations between the selected texture features and left ventricular function in dialysis patients. Texture features' performance in discrimination was evaluated by sensitivity and specificity. Reproducibility was estimated by the intraclass correlation coefficient (ICC). RESULTS: Dialysis patients had greater T1 values than normal (P < 0.05). Five texture features were filtered out through feature selection, and four showed a statistically significant difference between dialysis patients and healthy controls. Among the four features, vertical run-length nonuniformity (VRLN) had the most remarkable difference among the control and dialysis groups (144 ± 40 vs. 257 ± 74, P < 0.05), which overlap was much smaller than Global T1 times (1268 ± 38 vs. 1308 ± 46 msec, P < 0.05). The VRLN values were notably elevated (cutoff = 170) in dialysis patients, with a specificity of 97% and a sensitivity of 88%, compared with T1 times (specificity = 76%, sensitivity = 60%). In dialysis patients, VRLN was significantly and independently associated with left ventricular ejection fraction (P < 0.05), global longitudinal strain (P < 0.05), radial strain (P < 0.05), and circumferential strain (P < 0.05); however, T1 was not. DATA CONCLUSION: The texture features obtained by TA of T1 images and VRLN may be a better parameter for assessing myocardial alterations than T1 times. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 3.

This study aimed to investigate the correlation between increased extracellular matrix estimated by cardiac magnetic resonance (CMR) and left ventricular aneurysm after acute myocardial infarction.A total of 175 patients from 3 centers with an isolated left anterior descending culprit vessel underwent CMR examinations within 1 week and at a 6-month follow-up. Of these, 92 were identified to have left ventricular aneurysms (LVAs): 74 with functional aneurysm and 18 with anatomical aneurysm. The predictive significance of acute extracellular volume (ECV), left gadolinium enhancement (LGE), and other characteristics were analyzed using binary logistic regression analysis.Patients with LVA were more likely to present with left ventricular adverse remodeling (LVAR) than those without (p = 0.009). With optimal cutoff values of 30.90% for LGE and 33% for ECV to discriminate LVA from non-LVA, the area under the curve (AUC) by receiver operator characteristic curve (ROC) analysis was 0.92 (95% CI: 0.87-0.96; p0.001) and 0.93 (95% CI: 0.88-0.96; p0.001), respectively. ECV was significantly better than LGE at discriminating between functional and anatomical LVA (p0.001). Both acute LGE and ECV were predictors of LVA, with an odds ratio of 1.35 (95% CI: 1.21-1.52, p0.001) and 1.23 (95% CI: 1.13-1.33, p0.001), respectively, by multivariable logistic regression analysis.Acute LGE and ECV of the myocardium provided predictive significance for LVA. The discriminative significance of ECV for functional versus anatomical LVA was better than the discriminative significance of LGE.• Patients with LVA were more likely to present with LVAR. • Acute LGE and ECV of the myocardium provided the strongest predictive significance for LVA. • The discriminative significance of ECV for functional versus anatomical LVA was better than that of LGE.

BACKGROUND Acute myocardial infarction (AMI) is a disease with high morbidity and mortality worldwide and the evaluation of myocardial injury and perfusion status following myocardial ischemia and reperfusion is of clinical value. PURPOSE To assess the diagnostic utility of simplified perfusion fraction (SPF) in differentiating salvage and infarcted myocardium and its predictive value for left ventricular remodeling in patients with reperfusion ST-segment elevation myocardial infarction (STEMI). STUDY TYPE Prospective. POPULATION Forty-one reperfused STEMI patients and 20 healthy volunteers. FIELD STRENGTH/SEQUENCE 3.0T MRI. The MR examination included cine, T2 -short tau inversion recovery (T2 -STIR), first pass perfusiong (FPP)，phase sensitive inversion recovery (PSIR), and diffusion-weighted imaging (DWI). ASSESSMENT SPF values among different myocardium regions (infarcted, salvaged, remote, and MVO) and stages of reperfused STEMI patients as well as normal controls were measured. The diagnostic utility of SPF values in differentiating salvaged and infarcted myocardium was assessed. STATISTICAL ANALYSIS Independent t-test and the Mann-Whitney U-test. Logistic regression. RESULTS SPF values in healthy controls were not significantly different than SPF values in the remote myocardium of patients (40.09 ± 1.47% vs. 40.28 ± 1.93%, P = 0.698). In reperfusion STEMI patients, SPF values were lower in infarcted myocardium compared to remote and salvaged myocardium (32.15 ± 2.36% vs. 40.28 ± 1.93%, P

Direct stenting (DS) without pre-dilatation of the culprit lesion might improve myocardial perfusion and prognosis in patients undergoing percutaneous coronary intervention for ST-elevation myocardial infarction (STEMI); however, some studies report conflicting results. We investigated whether DS provides incremental myocardial benefits over conventional stenting (CS) in STEMI patients based on cardiac magnetic resonance imaging (CMR) measures. Reperfused patients who underwent CMR examinations within 1 week of STEMI onset were selected from a multicenter CMR registry of STEMI (NCT: 03768453). Patients were stratified into either a DS or CS group. Each group comprised 137 patients after 1:1 propensity score matching. Major adverse events (MACEs), including death, myocardial re-infarction, re-admission for heart failure, and stroke were noted during a median period of 44 months (interquartile range 32-58 months). DS was associated with larger (p = 0.007) and shorter (p = 0.005) stent sizes than CS. DS and CS achieved comparable angiographic TIMI-3 flow grades (p = 0.86) and myocardial blush grades (p = 0.70). There were no group differences regarding the incidence of CMR manifestations of microvascular dysfunction, including microvascular obstruction (MVO) (p = 0.89) and intramyocardial hemorrhage (p = 0.47), the extent of MVO (p = 0.21), infarction size (p = 0.83), or left ventricular ejection fraction (p = 0.57). Kaplan-Meier analysis revealed similar risks of MACEs (log rank p = 0.909), which occurred in 23.4% of DS and 26.3% of CS patients (p = 0.576). DS did not show any incremental benefits over CS on myocardial impairments as evaluated using CMR.Clinical Trial Registration: Clinicaltrials.gov, NCT: 03768453.

Left ventricular thrombus (LVT) after acute ST-segment elevation myocardial infarction (STEMI) are generally associated with poorer outcomes for patients at long-term follow-up. We hypothesis that tissue characteristics and strain parameters by cardiac magnetic resonance (CMR) imaging may indicate the interactions of LVT with ventricular myocardium remodeling at both acute stage and chronic stages in STEMI patients. This retrospective study included 111 consecutive STEMI patients (38 with LVT and 73 without LVT). All patients underwent CMR during acute stage (within 7 days) and chronic stage (after at least 2 months) periods after percutaneous coronary intervention (PCI). Left ventricular native T1, extracellular volume (ECV), radial, circumferential, and longitudinal strain were analyzed in both phases. Major adverse cardiac events (MACE, including cardiovascular death, myocardial reinfarction, and hospitalization for heart failure), thromboembolic and bleeding events, were the clinical endpoints of the study. During the acute stage, left ventricular ejection fraction (LVEF) (OR 0.77, P value = 0.01) and longitudinal strain (OR 1.90, P value < 0.001) were correlated with LVT formation. Strain parameters were reduced, while the native T1 and ECV values of both the infarcted area and remote myocardium were elevated in LVT patients. During the chronic stage, LVT resolved in 29 of 38 patients (76%). LVT remaining patients had lower LVEF, a larger LV, and higher ECV in the acute stage than those of the LVT-resolved patients. In the long-term follow up of 678 days, LVT (HR 2.45, P value = 0.02), aneurysm (HR 1.81, P value = 0.04), and native T1 (HR 2.44, P value = 0.01) were identified as three independent predictors of MACE, the incidence of thromboembolic events and bleeding events by a multivariable stepwise Cox proportional hazards regression. STEMI patients developing LVT had worse LV function, myocardial infarction extent, strain, and higher T1 and ECV values than STEMI patients without LVT. The LVT-remaining patients in the chronic stage had poorer functional and mapping parameters beginning in the first week. During the acute stage, LVEF and global longitudinal strain were independent correlated with LVT formation. During the long-term follow up, LVT, aneurysm and elevated myocardial T1 were associated with adverse outcomes in acute STEMI patients.

Background The presence of late gadolinium enhanced (LGE), which may enable better evaluation of myocardial impairment, would help predict the occurrence of life-threatening arrhythmias and major adverse cardiovascular events (MACE) in patients suffering from ischemic cardiomyopathy (ICM) and nonischemic cardiomyopathy (NICM) patients and who underwent a process of implantable cardioverter-defibrillator (ICD). Purpose To evaluate the prognostic value of cardiac MR-LGE for ICM and NICM patients with ICD. Study type Systematic review and meta-analysis. Population A total of 33 studies of 3457 patients were included. Field strength 1. 5T and 3.0T, LGE. Assessment PubMed, Cochrane Library, EMBASE, and Web of Science were systematically searched for studies reporting LGE in ICM or NICM patients with ICD implantation with several kinds of endpoints: MACE, life-threatening arrhythmia, cardiovascular mortality, and all-cause mortality. Statistical tests A meta-analysis was performed using a random-effects model to calculate odds ratios or standard mean differences (SMDs) for binary and continuous data. Results MR-LGE was positive in 1923 (55.6%) of ICM and NICM patients. LGE-present patients were more likely to have life-threatening arrhythmia (odds ratio [OR]: 5.1; 95% confidence interval [CI]: 3.8-6.8), MACE (OR: 5.2; 95% CI: 3.8-6.9), cardiovascular mortality (OR: 2.4; 95% CI: 1.2-4.6), and all-cause mortality (OR: 2.1; 95% CI: 1.3-3.4) compared with those without LGE. Moreover, ICM and NICM patients with LGE both had increased life-threatening arrhythmia (OR: 4.6; 95% CI: 2.7-8.0; OR: 5.2; 95% CI: 3.6-7.8, respectively) and MACE (OR: 4.7; 95% CI: 2.8-7.9; OR: 4.7; 95% CI: 2.7-8.1, respectively). Data conclusion The presence of MR-LGE may worsen the prognosis for adverse cardiovascular events in both ICM and NIMC patients who benefit more from ICDs. Level of evidence 3 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2020;51:1422-1439.

To assess the ability of distinguishing the area at risk (AAR) and evaluating the prognostic abilities of T2-mapping texture analysis (TA) in reperfused acute MI, 106 patients who were diagnosed with AMI and treated with percutaneous coronary intervention (PCI) underwent acute (less than five days) enhanced cardiac magnetic resonance imaging. Of these patients, 45 of them had a subsequent CMR scan following recovery (after at least three months). Cine imaging, T2-Mapping, T2-weighted STIR imaging, and LGE imaging were performed. In the TA, regions of interest (infarcted, salvageable, and remote) were drawn by two blinded, independent readers based on LGE and T2-weighted imaging. Seven independent texture features on T2-Mapping were selected: Perc.50%, S(2,2)InvDfMom, S(2.-2)AngScMom, S(4,0)Entropy, 45dgrLngREmph, 45dgr_Fraction and 135dr_GLevNonU. Among them, 45dgr_LngREmph, 45dgr_Fraction and 135dr_GLevNonU showed more promise. The average value of 135dr_GLevNonU in the infarct zone, AAR zone, and the remote zone was: 61.96 ± 26.03, 31.811 ± 18.933 and 99.839 ± 26.231, respectively. Additionally, 135dr_GLevNonU provided the highest 0.855(± 0.083) area under the curve (AUC) from the receiver operating characteristic curve (ROC curve) for distinguishing AAR from the infarct zone. The AUC for differentiating AAR from the remote zone is 0.942 ± 0.041. Texture features are not associated with convalescent decreased strain or ejection fraction (EF) (p > 0.05) in the standard regression analysis; and cannot predict left ventricle remodeling (LVR) in the logistic regression analysis (p > 0.05). T2-mapping TA in reperfused AMI can distinguish AAR from both the infarct zone and the remote myocardial zone without LGE imaging. However, these features cannot predict patients’ functional recovery in the convalescent stage.

Aims In order to determine acute cardiac involvement in patients with COVID-19, we quantitatively evaluated tissue characteristics and mechanics by non-invasive cardiac magnetic resonance (CMR) in a cohort of patients within the first 10 days of the onset of COVID symptoms. Methods and results Twenty-five patients with reverse transcription polymerase chain reaction confirmed COVID-19 and at least one marker of cardiac involvement [cardiac symptoms, abnormal electrocardiograph (ECG), or abnormal cardiac biomarkers] and 25 healthy age- and gender-matched control subjects were recruited to the study. Patients were divided into those with elevated (n = 8) or normal TnI (n = 17). There were significant differences in global longitudinal strain among patients who were positive and negative for hs-TnI, and controls [−12.3 (−13.3, −11.5)%, −13.1 (−14.2, −9.8)%, and −15.7 (−18.3, −12.7)%, P = 0.004]. Native myocardial T1 relaxation times in patients with positive and negative hs-TnI manifestation (1169.8 ± 12.9 and 1113.2 ± 31.2 ms) were significantly higher than the normal (1065 ± 57 ms) subjects, respectively (P Conclusion In patients with early-stage COVID-19, myocardial oedema, and functional abnormalities are a frequent finding, while irreversible regional injury such as necrosis may be infrequent.

Diffusion-weighted imaging (DWI) has been confirmed to be associated with late gadolinium enhancement (LGE) in hypertrophic cardiomyopathy (HCM). In this context, we aimed to study whether DWI could reflect the active tissue injury and edema information of HCM which were usually indicated by T2 weighted images. Forty HCM patients were examined using a 3.0 T magnetic resonance scanner. Cine, T2-weighted short tau inversion recovery (T2-STIR), DWI and LGE sequences were acquired. T1 mapping was also included to quantify the focal and diffuse fibrosis. Cardiac troponin I (cTnI) was tested to assess the recently myocardial injury. Student’s t-test, Mann–Whitney U test, One-way analysis, Kruskal–Wallis analysis, the Spearman correlation analysis, and multivariable regression were used in this study. The apparent diffusion coefficient (ADC) was significantly elevated in the cTnI positive group (P = 0.01) and correlated with LGE (ρ = 0.312, P = 0.049) and HighT2 extent (ρ = 0.443, P = 0.004) in the global level. In the segmental analysis, the ADC significantly differentiated the segments with and without HighT2/LGE presence (P = 0.00). The average ADC values were higher in segments with HighT2 and LGE coexistence than in those with only LGE presence (P

Our study sought to explore the prognostic value of radiomic TA (texture analysis) on quantitative ECV (extracellular volume) fraction mapping to differentiate between reversible and irreversible myocardial damage and to predict left ventricular adverse remodeling in patients with reperfused STEMI (ST-elevation myocardial infarction). This observational prospective cohort study identified 70 patients (62 ± 9 years, 62 men [85.70%]) with STEMI for TA who consecutively performed native and contrast T1 mapping. Texture features were extracted from each stack of ECV mapping based on ROI (region of interest) analysis. After texture feature selection and dimension reduction, five selected texture features were found to be statistically significant for differentiating the extent of myocardial injury. ROC (receiver operating characteristic) curve analysis for the differentiation of unsalvageable infarction and salvageable myocardium demonstrated a significantly higher AUC (area under the curve) (0.91 [95% CI, 0.86–0.96], p

BACKGROUND The use of native T1 mapping for evaluation of hypertrophic cardiomyopathy (HCM) is being explored, and its combination with histogram analysis may benefit the accuracy of such assessments. PURPOSE To investigate the relationship of segmental left ventricular wall thickness (LVWT), myocardial fibrosis, and strain parameters with segmental histogram parameters of native T1 mapping in HCM patients. STUDY TYPE Retrospective. SUBJECTS Ninety-three HCM patients without previous cardiovascular diseases were included. FIELD STRENGTH/SEQUENCE 3.0T cardiac MR. Steady-state free precession cine imaging, modified Look-Locker inversion recovery, phase-sensitive inversion recovery. ASSESSMENT Images were assessed by three experienced radiologists. STATISTICAL TESTS Mann-Whitney U-tests, area under the curve (AUC), Spearman's rank correlation, intraclass correlation coefficient, and Bland-Altman test were used for statistical analysis. RESULTS A higher LVWT value correlated with higher means, minimums, 10th /25th /50th /75th /90th percentiles, maximums, kurtosis, entropy, and lower SD and energy of T1 mapping (P < 0.05 for all), with the correlation being stronger for entropy and energy (Spearman's rho = 0.439 and -0.413, respectively) than other parameters. Late gadolinium enhancement positive (LGE+) segments exhibited higher mean, minimum, 10th /25th /50th /75th /90th percentiles, maximum, entropy, and lower energy of T1 times than late gadolinium enhancement negative (LGE-) segments (P < 0.001 for all). Impaired strain function parameters (peak thickening and thickening rate in radial, circumferential, and longitudinal directions) demonstrated a weak correlation with higher entropy (P < 0.001 for all) and lower energy (P < 0.001 for all). DATA CONCLUSION Histogram parameters of native T1 mapping provide more information than mean T1 times alone. Among these parameters, entropy and energy may correlate better with LVWT, myocardial late gadolinium enhancement, and strain parameters than mean T1 times in HCM patients. LEVEL OF EVIDENCE 2 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019;49:668-677.

BOLD imaging is a quantitative MRI technique allowing the evaluation of the balance between supply/demand in myocardial oxygenation and myocardial haemorrhage. We sought to investigate the ability of BOLD imaging to differentiate reversible from irreversible myocardial injury as well as the chronological progression of myocardial oxygenation after reperfusion in patients with ST segment elevation myocardial infarction (STEMI). Twenty-two patients (age, 60 ± 11 years; 77.3% male) with STEMI underwent cardiac MRIs on four occasions: on days 1, 3, 7 and 30 after reperfusion. BOLD MRI was obtained with a multi-echo turbo field echo (TFE) sequence on a 3-T scanner to assess myocardial oxygenation in MI. T2* value in MI with intramyocardial haemorrhage (IMH) was the lowest (9.77 ± 3.29 ms), while that of the salvaged zone was the highest (33.97 ± 3.42 ms). T2* values in salvaged myocardium demonstrated a unimodal temporal pattern from days 1 (37.91 ± 2.23 ms) to 30 (30.68 ± 1.59 ms). T2* values in the MI regions were significantly lower than those in remote myocardium, although the trends in both were constant overall. There was a slightly positive correlation between T2* in MI regions and EF (Rho = 0.27, p < 0.05) or SV (Rho = 0.22, p = 0.04) and a slightly negative correlation between T2* in salvaged myocardium and LVEDV (Rho = – 0.23, p < 0.05). BOLD MRI performed in post-STEMI patients allows accurate evaluation of myocardial damage severity and could differentiate reversible from irreversible myocardial injury. The increased T2* values may imply the pathophysiological mechanism of salvaged myocardium. BOLD MRI could represent a more accurate alternative to the other currently available options. • Myocardial oxygenation and haemorrhage after myocardial infarction affect BOLD MRI values • BOLD MRI could be used to differentiate irreversible from reversible myocardial damage • Changed oxygenation implies the pathophysiological mechanism of salvaged myocardium

BOLD (blood oxygen level dependent) MRI can detect regional condition of myocardial oxygen supply and demand by means of paramagnetic properties.Noninvasive assessment of myocardial oxygenation by BOLD MRI in hypertensive patients with hypertension (HTN) left ventricular myocardial hypertrophy (LVMH) and HTN non-LVMH and its correlation with myocardial mechanics were performed.Prospective.Twenty patients with HTN LVMH, 21 patients with HTN non-LVMH, and 23 normotensive controls were enrolled.Cine imaging, T2* and T1 mapping sequences were achieved at 3.0T.Dedicated T1 mapping, T2*, and cine imaging analysis were performed by two radiologists using cvi42.One-way analysis of variance, Kruskal-Wallis test, Bland-Altman analysis, Pearson's correlation coefficient, Spearman's rank correlation.T2* values of HTN LVMH group were significantly lower versus the controls (23.78 ± 3.09 versus 30.77 ± 2.71; P 0.001) and HTN non-LVMH group (23.78 ± 3.09 versus 28.64 ± 4.23; P 0.001). Left ventricular peak circumferential strain were reduced in HTN LVMH patients compared with other two groups (-11.32 [-15.64, -10.3], -16.78 [-19.35, -15.34], and -19.73 [-20.57, -18.73]; P 0.05); and longitudinal strain of HTN LVMH patients were lower than other two groups (-11.31 ± 2.91, -15.1 ± 3.06, and -18.85 ± 1.85; P 0.05); radial strain of HTN LVMH patients were also lower than other two groups (25.03 ± 16, 40.95 ± 17.5 and 47.9 ± 10.23; P 0.05). Extracellular volume correlated with peak circumferential, longitudinal, and radial strain (spearman rho = 0.6, 0.64, and -0.69; P 0.05), respectively; T2* negatively correlated with peak circumferential and longitudinal strain (spearman rho = -0.43 and -0.49; P 0.05), respectively. Patients with lower T2* values had significant decreases in myocardial mechanics (P 0.05).HTN LVMH patients have both impaired myocardial mechanics and decreased T2* values compared with HTN non-LVMH and normotensive groups. BOLD MRI could provide a feasible assessment modality for detecting altered T2* due to the change of de-oxygenated hemoglobin and hence to the change of signal intensity in oxygenation-sensitive images.1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1297-1306.

BACKGROUND Previous studies have shown that diffusion-weighted imaging (DWI) is sensitive to myocardial fibrosis in ischemic and nonischemic cardiomyopathy. PURPOSE To explore the prognostic value of apparent diffusion coefficient (ADC) for detecting myocardial fibrosis and its relationship to the contractile function in hypertrophic cardiomyopathy (HCM). STUDY TYPE Prospective. POPULATION A total of 45 HCM patients and 20 controls. FIELD STRENGTH/SEQUENCE 3.0T cardiac MRI. The cardiac MR sequences included cine, T1 mapping, and DWI. ASSESSMENT According to the presence of late gadolinium enhancement (LGE) and the extracellular volume (ECV) values (+2 SD of control subjects), respectively, reader W and reader J assessed the value of ADC of each segment for detecting myocardial fibrosis and its relationship to impaired contractile function in HCM patients. STATISTICAL TESTS Independent sample t-test, Pearson analysis, and intraclass correlation (ICC). RESULTS The value of ECV was 23.6 ± 3.0% for control. ECV ≥ 29.6% and ECV

This study assessed the extent of fibrosis and the relationship between the ADC value and systolic strain in hypertensive patients with left ventricular hypertrophy (HTN LVH) and hypertensive patients without LVH (HTN non-LVH) using cardiac diffusion-weighted imaging and T1 mapping. T1 mapping was performed in 13 HTN LVH (mean age, 56.23 ± 3.30 years), 17 HTN non-LVH (mean age, 56.41 ± 2.78 years), and 12 normal control subjects (mean age, 55.67 ± 3.08 years) with 3.0 T MRI using cardiac diffusion-weighted imaging and T1 mapping. HTN LVH subjects had higher native T1 (1233.12 ± 79.01) compared with controls (1133.88 ± 27.40) (p 2 = 0.210). Increased levels of ADC were associated with reduced peak systolic and early diastolic circumferential strain rates across all subjects. Contrast-free DW-CMR is an alternative sequence to ECV for the evaluation of fibrosis extent in HTN LVH and HTN non-LVH, while native T1 has limited value.

BACKGROUND BOLD (blood oxygen level dependent) MRI can detect regional condition of myocardial oxygen supply and demand by means of paramagnetic properties. PURPOSE Noninvasive assessment of myocardial oxygenation by BOLD MRI in hypertensive patients with hypertension (HTN) left ventricular myocardial hypertrophy (LVMH) and HTN non-LVMH and its correlation with myocardial mechanics were performed. STUDY TYPE Prospective. POPULATION Twenty patients with HTN LVMH, 21 patients with HTN non-LVMH, and 23 normotensive controls were enrolled. FIELD STRENGTH/SEQUENCE Cine imaging, T2* and T1 mapping sequences were achieved at 3.0T. ASSESSMENT Dedicated T1 mapping, T2*, and cine imaging analysis were performed by two radiologists using cvi42. STATISTICAL TESTS One-way analysis of variance, Kruskal-Wallis test, Bland-Altman analysis, Pearson's correlation coefficient, Spearman's rank correlation. RESULTS T2* values of HTN LVMH group were significantly lower versus the controls (23.78 ± 3.09 versus 30.77 ± 2.71; P

BACKGROUND The relationship between dynamic changes of myocardial injury in ST-elevation myocardial infarction (STEMI) patients and long-term prognosis is still unclear. PURPOSE To evaluate the extracellular volume fraction (ECV) in the differentiation of reversible from irreversible myocardial injury and the prediction value of left ventricular adverse remodeling in patients with STEMI after reperfusion. STUDY TYPE Prospective. POPULATION Twenty-four STEMI patients after reperfusion were included FIELD STRENGTH/SEQUENCE: 3.0 T, T1 mapping, ECV, T2 -STIR, and late gadolinium enhancement (LGE). ASSESSMENT All the patients underwent cardiac MRI at four timepoints (days 1, 3, and 7, and at 6 months). The regions of interest (ROIs) were selected at the infarcted myocardium (with/without intramyocardial hemorrhage [IMH] and microvascular obstruction [MVO]). STATISTICAL TESTS One-way analysis of variance and the Kruskal-Wallis test were used for the statistical analysis. RESULTS Native T1 of MI (without MVO/IMH) gradually decreased after reperfusion (P

Trichophoreae is a nearly cosmopolitan Cyperaceae tribe that contains ~17 species displaying striking variation in size, inflorescence complexity, and perianth morphology. Although morphologically distinct, the status of its three genera (Cypringlea, Oreobolopsis and Trichophorum) is controversial because recent phylogenetic studies have suggested they might not be reciprocally monophyletic. However, previous analyses have shown conflicting topologies and consistently poor support due to an initial rapid diversification of the tribe. We analysed restriction-site associated DNA sequencing (RADseq) data from nearly all species of the clade, combined with five Sanger-based markers (matK, ndhF, rps16, ETS-1f, ITS) sampled extensively within species. This approach allowed us to resolve deep and shallow relationships within Trichophoreae for the first time, despite an anomaly zone spanning several successive short branches that produced considerable gene tree incongruence. Analyses reveal a primary phylogenetic split of the tribe into two clades roughly corresponding to an East Asian-North American disjunction that dates back to the mid-Miocene, with both clades comprised of a mixture of reduced unispicate and larger taxa with highly compound inflorescences. Morphological characters traditionally used in the circumscription of Trichophoreae genera are shown to be homoplasious. Several of these characters correlate best with climatic conditions, with the most reduced species occurring in open habitats at high latitudes and altitudes. Close relatives with highly compound inflorescences are found in temperate or subtropical forest understories. Cypringlea and Oreobolopsis are deeply nested within Trichophorum, and we merge all three genera into a more broadly circumscribed Trichophorum. We also show that Scirpus filipes is another previously unrecognized East Asian species of Trichophorum with highly compound inflorescences.

Purpose To investigate the feasibility and diagnostic value of intravoxel incoherent motion (IVIM) in the assessment of myocardial fibrosis in hypertrophic cardiomyopathy (HCM) patients. Methods Fifty-five HCM patients underwent IVIM diffusion-weighted cardiovascular resonance imaging; Cine, T1 mapping, IVIM and late gadolinium enhancement (LGE) were performed. The relationship of strain, pre T1, extracellular volume (ECV), IVIM-derived parameters (D, D* and f) and LGE were analyzed based on 16 American Heart Association segments. Abnormal segments of myocardial fibrosis were defined as: the presence of LGE (LGE+) or ECV ≥ 29.6 %. Results D parameter was significantly increased in LGE + vs LGE- (1.89 ± 0.14 μm2/ms vs. 1.63 ± 0.12 μm2/ms, p Conclusions : IVIM DW-CMR has proven to be ingenious in the investigation of myocardial fibrosis; D* and f parameters may have potential value to assess the perfusion status of fibrotic regions in HCM patients.

The association between global and segmental myocardial strain impairment and fibrosis extent in hypertrophic cardiomyopathy (HCM) is widely verified. The aim of this study was to investigate the contribution of high T2-weighted signal intensity (HighT2) to myocardial deformation in HCM. We prospectively recruited 57 patients with HCM examined by a 3.0 Tesla magnetic resonance scanner with cine, T2-weighted imaging with fat saturation and phase-sensitive inversion recovery. Global and segmental radial, circumferential and longitudinal strains were included for analysis. The extent of HighT2 was negatively correlated with global radial strain (ρ = −0.275, p = 0.038) and positively correlated with global circumferential strain (ρ = 0.308, p = 0.02) and global longitudinal strain (ρ = 0.422, p = 0.001). Radial, circumferential and longitudinal strains were all significantly associated with segment thickness. Regarding circumferential strain, segments at the mid-ventricular level with LGE and HighT2 showed more impairment than segments with only LGE. For longitudinal strain, the influence of HighT2 appeared only at the mid-ventricular level. The HighT2 extent in HCM was observed to contribute to global and segmental strain parameters. At the segmental level, HighT2 indeed affects left ventricular deformation, and follow-up studies are still warranted.

AIM To assess the potential of texture analysis (TA) applied in T1 maps and extracellular volume (ECV) obtained using cardiac magnetic resonance (CMR) in the diagnosis of hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HHD) compared with normal controls (NC). Strain parameters were analysed to compare with final TA models. MATERIALS AND METHODS This retrospective study included 66 HCM patients, 39 HHD patients, and 41 NC. Step-wise dimension reduction and feature selection were performed by reproducibility, machine learning, collinearity, and multivariable regression analysis to select the texture features that enable diagnosis of and differentiation between HCM and HHD. Strain parameters were calculated by short-axis and three long-axis cine sequences. RESULTS Independent features in T1 maps and ECV analysis allowed for the differentiation between patients (HCM and HHD) and NC. Of the best-calculated model, the areas under the receiver operating curve (AUCs) were as follows: 0.969 for T1 map and 0.964 for ECV. To distinguish HCM from HHD, two independent features were screened out for both T1 and ECV maps. The AUCs were as follows: 0.793 for T1 map and 0.894 for ECV. Radial, circumferential, and longitudinal strain parameters could differentiate patients from NC, but only longitudinal strain parameters was significantly different between HCM and HHD. CONCLUSIONS Texture analysis of T1 maps and ECV shows high accuracy in differentiating hypertrophic myocardium from NC, and HCM from HHD. Strain parameters are able to demonstrate the difference between patients and NC, but were less impressive in differentiating HCM and HHD.

To identify myocardial fibrosis in hypertrophic cardiomyopathy (HCM) subjects using quantitative cardiac diffusion-weighted imaging (DWI) and to compare its performance with native T1 mapping and extracellular volume (ECV). Thirty-eight HCM subjects (mean age, 53 ± 9 years) and 14 normal controls (mean age, 51 ± 8 years) underwent cardiac magnetic resonance imaging (CMRI) on a 3.0T magnetic resonance (MR) machine with DWI, T1 mapping and late gadolinium enhancement (LGE) imaging as the reference standard. The mean apparent diffusion coefficient (ADC), native T1 value and ECV were determined for each subject. Overall, the HCM subjects exhibited an increased native T1 value (1241.04 ± 78.50 ms), ECV (0.31 ± 0.03) and ADC (2.36 ± 0.34 s/mm(2)) compared with the normal controls (1114.60 ± 37.99 ms, 0.24 ± 0.04, and 1.62 ± 0.38 s/mm(2), respectively) (p 0.05). DWI differentiated healthy and fibrotic myocardia with an area under the curve (AUC) of 0.93, while the AUCs of the native T1 values (0.93), (p 0.05) and ECV (0.94), (p 0.05) exhibited an equal differentiation ability. Both HCM LGE+ and HCM LGE- subjects had an increased native T1 value, ECV and ADC compared to the normal controls (p 0.05). HCM LGE+ subjects exhibited an increased ECV (0.31 ± 0.04) and ADC (2.43 ± 0.36 s/mm(2)) compared to HCM LGE- subjects (p 0.05). HCM LGE+ and HCM LGE- subjects had similar native T1 values (1250 ± 76.36 ms vs. 1213.98 ± 92.30 ms, respectively) (p 0.05). ADC values were linearly associated with increased ECV (R(2) = 0.36) and native T1 values (R(2) = 0.40) among all subjects. DWI is a feasible alternative to native T1 mapping and ECV for the identification of myocardial fibrosis in patients with HCM. DWI and ECV can quantitatively characterize the extent of fibrosis in HCM LGE+ and HCM LGE- patients.

AIM To investigate the feasibility and prognostic value of biventricular strain analysis for patients with systemic lupus erythematosus (SLE) and relationship to left ventricular (LV) myocardial fibrosis, pulmonary hypertension (PAH), and right ventricular (RV) ejection fraction (RVEF). MATERIALS AND METHODS A total of 50 SLE patients (47 women; 34.4±12 years) and 15 controls (13 women; 32.9±8.6 years) were imaged via echocardiography and a 3 T magnetic resonance imaging (MRI). Pulmonary artery systolic pressure (sPAP) was assessed using echocardiography. Biventricular global circumferential strain (GCS), global longitudinal strain (GLS), global circumferential strain rate (GCSR), and global longitudinal strain rate (GLSR) as well as LV myocardial extracellular volume (ECV) were derived for each subject. RESULTS Elevated LV ECV was significantly associated with LV GCS (beta –0.428, p=0.000), GLS (beta 0.404, p=0.000), GCSR (beta –0.350, p=0.006), GLSR (beta –0.445, p=0.000) and RV GCS (beta –0.373, p=0.000), and the presence of reduced RVEF was significantly associated with LV GCS (beta –0.338, p=0.002), GLS (beta –0.465, p=0.000) and RV GCS (beta –0.465, p=0.000). Raised sPAP was significantly associated with RV GLS (beta 0.445, p=0.000) and GCSR (beta –0.387, p=0.001). Moreover, there were significantly correlations between LV and RV strain and strain rate. CONCLUSIONS Biventricular strain analysis may be a better prognostic tool for patients with SLE as it allows greater comprehensive analysis and more definitive treatment planning compared to separate assessment of LV or RV contractility.

The use of native TTo investigate the relationship of segmental left ventricular wall thickness (LVWT), myocardial fibrosis, and strain parameters with segmental histogram parameters of native TRetrospective.Ninety-three HCM patients without previous cardiovascular diseases were included.3.0T cardiac MR. Steady-state free precession cine imaging, modified Look-Locker inversion recovery, phase-sensitive inversion recovery.Images were assessed by three experienced radiologists.Mann-Whitney U-tests, area under the curve (AUC), Spearman's rank correlation, intraclass correlation coefficient, and Bland-Altman test were used for statistical analysis.A higher LVWT value correlated with higher means, minimums, 10Histogram parameters of native T2 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019;49:668-677.

Acute myocardial infarction (AMI) is a major cause of morbidity and mortality worldwide and places a significant financial burden on our society.To determine the feasibility of cardiac intravoxel incoherent motion (IVIM) in the consecutive evaluation of myocardial perfusion in myocardial infarction patients postpercutaneous coronary intervention (PCI) and to investigate the dynamic biological phenomena in myocardial perfusion after AMI.Prospective observational study.Twenty ST-segment elevation myocardial infarction (STEMI) patients after reperfusion therapy and 12 healthy volunteers served as controls.Cardiac MRI at 3T, including steady-state free precession (SSFP) cine imaging, TMyocardial TIndependent sample's t-test, Pearson's, and Spearman's correlation and interobserver variability were applied. P ≤ 0.05 was considered significant.The TThis preliminary study demonstrated that a dynamic process exists in the status of myocardial edema and myocardial perfusion in MI patients after PCI. The findings suggest myocardial perfusion would be best evaluated between day 3 and day 7.2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;48:1602-1609.

Previous studies have shown that diffusion-weighted imaging (DWI) is sensitive to myocardial fibrosis in ischemic and nonischemic cardiomyopathy.To explore the prognostic value of apparent diffusion coefficient (ADC) for detecting myocardial fibrosis and its relationship to the contractile function in hypertrophic cardiomyopathy (HCM).Prospective.A total of 45 HCM patients and 20 controls.3.0T cardiac MRI. The cardiac MR sequences included cine, TAccording to the presence of late gadolinium enhancement (LGE) and the extracellular volume (ECV) values (+2 SD of control subjects), respectively, reader W and reader J assessed the value of ADC of each segment for detecting myocardial fibrosis and its relationship to impaired contractile function in HCM patients.Independent sample t-test, Pearson analysis, and intraclass correlation (ICC).The value of ECV was 23.6 ± 3.0% for control. ECV ≥ 29.6% and ECV 29.6% groups were classified. ADC values in the ECV ≥ 29.6% group were significantly increased compared to the ECV 29.6% group, (2.41 ± 0.23 μmContractile dysfunction in HCM is predominantly associated with ADC, which is a feasible alternative to ECV and LGE for detecting myocardial fibrosis.1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;48:1139-1146.

This paper studies the causal relationship between energy consumption and economic growth in Beijing by using econometric method from 1980 to 2012, and then establishes the model between the energy consumption of three industries and economic growth to study the influence of the secondary industry and tertiary industry energy consumption on economic growth in Beijing. Finally, we put forward counter measures and suggestions on sustainable development of Beijing's economy and energy industry.

The hot ductility of V-N and V-Nb microalloyed steels was investigated on a Gleeble-1500 thermomechanical simulator, and the results were compared with those of V and Nb microalloyed steels. A ductility trough is found in both the steels in the temperature range of 700 to 1050°C. Compared to the V steel, the V-N steel has a wider and deeper ductility trough with the increase of N content, due to the increased precipitation of V(C, N) in the steel. Above 930°C, when 0.047wt% V is added to the 0.028wt% Nb-containing steel, the ductility becomes worse, owing to the rise of the onset dynamic recrystallization temperature. However, the ductility gets better at 800 to 930°C because of the coarsening of precipitates in austenite. With the improvement in ductility, the fracture mechanism is changed from intergranular to high ductile fracture in the temperature range of 800 to 1050°C.

The continuous cooling transformation (CCT) behaviors of two vanadium (V) micro-alloyed steels with different Nitrogen (N) levels were investigated under the undeformed and deformed conditions, respectively. It is found that the austenite-bainite transformation is suppressed during dynamic CCT process due to hot deformation. For V-N steel, the transformation of austenite-proeutectoid ferrite and austenite-acicular ferrite (AF) occur under a wider range of cooling rates.

Platanthera consists about 150–200 species and is among the largest terrestrial orchid genera; it is distributed across Asia, North America and Europe with a few species extending into North Africa and Central America (Bateman et al. 2003, 2009, Chase et al . 2015, Chen et al . 2009, Luer 1975, Pearce & Cribb 2002, Pridgeon et al. 2001, Lang 1999, Efimov 2016, Raskoti et al. 2016). There are about 50 species of Platanthera in China, out of which 25 species are endemic (Lang 1999, Chen et al . 2009, Jin et al. 2012, 2013,2014,2015, Efimov 2016). During fieldwork in eastern China, a leafless but visibly green Platanthera was discovered. This species is sympatric and similar to Platanthera minor , but it is easy to distinguish from the latter on the basis of vegetative and floral characters. Here we considered this little known Platanthera as a new species.

Swertia subuniflora is described from Fujian Province, China. Morphological and molecular evidences indicate its close relationship with S. franchetiana, S. mussotii and S. punicea, three species from Swertia series Japonica (further grouped in section Swertopsis, subgenus Ophelia). The new species can be recognized by its solitary flowers and ovate-cordate stem leaves.