Impaired myocardial structure and function assessment by cardiac MR in Takayasu arteritis with pulmonary artery involvement / 中华放射学杂志

Objective:To analyze the late gadolinium enhancement (LGE) manifestations, cardiac function, and myocardial strain by feature tracking (FT) in Takayasu arteritis (TA) with pulmonary artery involvement (PTA) using cardiac MR (CMR), and then to investigate manifestations of the impaired myocardial structure and function.Methods:A retrospective study was performed on 32 patients with PTA and 21 healthy subjects without cardiopulmonary diseases from January 2017 to December 2020. All of them underwent CMR examinations. According to the presence of pulmonary arterial hypertension (PAH),PTA patients were divided into two groups including PAH group (11 cases) and non-PAH group (21 cases). LGE manifestations were observed and Fisher exact test was used for statistical analysis between the two groups. Cardiac function parameters and FT values including global peak strain of the left and right ventricle were calculated separately in PAH, non-PAH group of patients and healthy controls, using One-way ANOVA or non-parametric Kruskal-Wallis test for statistical analysis including a pairwise comparison between groups. The correlations between FT values of the PAH group and parameters measured by right heart catheterization test (RHC) and transthoracic echocardiography were analyzed using Pearson or Spearman correlation analysis.Results:There were 23 PTA patients (71.9%) with LGE. LGE in the interventricular insertion points (IPs)(11/11), and in the mid-wall (11/11) or epicardial (10/11) myocardium was more common ( P values were 0.006,<0.001 and 0.011, respectively) in PAH group, compared with LGE in the IPs (11/21), and in the mid-wall (7/21) or epicardial (9/21) myocardium in non-PAH group. The absolute values of left ventricular global peak circumferential strain (LVGPCS), left ventricular global peak longitudinal strain (LVGPLS) and right ventricular global peak longitudinal strain in PAH group were smaller than those in healthy subjects ( P<0.05). The absolute values of LVGPCS and LVGPLS in non-PAH group were smaller than those in healthy subjects ( P<0.05). In PAH group, mean pulmonary artery pressure of RHC was correlated with several FT parameters ( P<0.05), especially left ventricular global peak radial strain ( r=-0.807, P=0.009) and LVGPCS ( r s=0.817, P=0.007). Conclusions:Myocardial injury can be seen in PTA patients. And LGE in the IPs and LGE in the mid-wall or epicardial myocardium is more common in PTA patients with PAH. LVGPCS and LVGPLS can early indicate left heart dysfunction in PTA patients without PAH.

Cardiac magnetic resonance-feature tracking technique can assess cardiac function and prognosis in patients with myocardial amyloidosis / 南方医科大学学报

OBJECTIVE@#To quantitatively assess cardiac functions in patients with cardiac amyloidosis (CA) and hypertrophic cardiomyopathy (HCM) using cardiac magnetic resonance-feature tracking (CMR-FT) technique and evaluate the prognostic value of CMR-FT in patients with CA.@*METHODS@#We retrospectively collected the data from 31 CA patients with systemic amyloidosis confirmed by Congo red staining and serum immunohistochemistry after extracardiac tissue biopsy undergoing CMR at our hospital from March, 2013 to June, 2021.Thirty-one age and gender matched patients with asymmetric left ventricular wall hypertrophy and 31 healthy individuals without organic or functional heart disease served as the controls.Radial, circumferential and longitudinal strains and strain rates of the left ventricle at the global level and in each myocardial segment (basal, middle and apical) were obtained with CMR-FT technique and compared among the 3 groups.The predictive value of myocardial strains and strain rates for all-cause mortality in CA patients was analyzed using a stepwise COX regression model.@*RESULTS@#The left ventricular volume, myocardial mass, ejection fraction and cardiac output differed significantly among the groups (P < 0.05).Except for apical longitudinal strain, the global and segmental strains were all significantly lower in CA group than in HCM group (P < 0.05).The global and segmental strains were all significantly lower in CA group than in the healthy individuals (P < 0.05).The basal strain rates in the 3 directions were significantly lower in CA group than in the healthy individuals (P < 0.05), but the difference in apical strain rates was not statistically significant between the two groups.Multivariate stepwise COX analysis showed that troponin T (HR=1.05, 95%CI: 1.01-1.10, P=0.017) and middle peak diastolic circumferential strain rate (HR=6.87, 95%CI: 1.52-31.06, P=0.012) were strong predictors of death in CA patients.@*CONCLUSION@#Strain and strain rate parameters derived from CMR-FT based on cine sequences are new noninvasive imaging markers for assessing cardiac impairment in CA and cardiac function changes in HCM, and provide independent predictive information for all-cause mortality in CA patients.

Relationship of Microvascular Obstruction with Global and Regional Myocardial Function Determined by Cardiac Magnetic Resonance after ST-Segment Elevation Myocardial Infarction / 中国医学科学杂志(英文版)

Objective To investigate the impact of microvascular obstruction (MVO) on the global and regional myocardial function by cardiac magnetic resonance feature-tracking (CMR-FT) in ST-segment-elevation myocardial infarction (STEMI) patients after percutaneous coronary intervention.Methods Consecutive acute STEMI patients who underwent cardiac magnetic resonance imaging 1 - 7 days after successful reperfusion by percutaneous coronary intervention treatment were included in this retrospective study. Based on the presence or absence of MVO on late gadolinium enhancement images, patients were divided into groups with MVO and without MVO. The infarct zone, adjacent zone, and remote zone were determined based on a myocardial 16-segment model. The radial strain (RS), circumferential strain (CS), and longitudinal strain (LS) of the global left ventricle (LV) and the infarct, adjacent, and remote zones were measured by CMR-FT from cine images and compared between patients with and without MVO using independent-samples t-test. Logistic regression analysis was used to assess the association of MVO with the impaired LV function.Results A total of 157 STEMI patients (mean age 56.66 ± 11.38 years) were enrolled. MVO was detected in 37.58% (59/157) of STEMI patients, and the mean size of MVO was 3.00 ±3.76 mL. Compared with patients without MVO (n =98 ), the MVO group had significantly reduced LV global RS (t= -4.30, P < 0.001), global CS (t= 4.99, P < 0.001), and global LS ( t= 3.51, P = 0.001). The RS and CS of the infarct zone in patients with MVO were significantly reduced (t= -3.38, P = 0.001; t= 2.64, P = 0.01; respectively) and the infarct size was significantly larger (t= 8.37, P < 0.001) than that of patients without MVO. The presence of LV MVO [OR= 4.10, 95%CI: 2.05 - 8.19, P<0.001) and its size [OR=1.38, 95%CI: 1.10-1.72, P=0.01], along with the heart rate and LV infarct size were significantly associated with impaired LV global CS in univariable Logistic regression analysis, while only heart rate (OR=1.08, 95%CI: 1.03 - 1.13, P=0.001) and LV infarct size (OR=1.10, 95%CI: 1.03 - 1.16, P=0.003) were independent influencing factors for the impaired LV global CS in multivariable Logistic regression analysis.Conclusion The infarct size was larger in STEMI patients with MVO, and MVO deteriorates the global and regional LV myocardial function.

Papel de la ecocardiografía speckle-tracking (rastreo de marcas) y la resonancia magnética cardíaca-feature tracking en la circulación de Fontan. Diferencias entre los ventrículos derecho e izquierdo / Speckle-tracking echocardiography and MCR-feature tracking in Fontan circulation. Differences between right and left ventricles

Resumen Introducción: En los pacientes con DCPT, la disfunción ventricular es inevitable, y más temprana en VU derechos. La deformación miocárdica por STE y RMC-FT parece promisoria. Objetivo: Analizar la función ventricular mediante STE y RMC-FT en pacientes con DCPT, en comparación con RMC convencional según la morfología del VU y la posible implicación en su diagnóstico temprano. Método: Se recogieron medidas del strain longitudinal y circunferencial por STE y RMC-FT, volúmenes ventriculares y FE por RMC en 64 pacientes con DCPT. Resultados: La morfología ventricular no se relacionó con disfunción por RMC. Los VU derechos tuvieron valores por STE y RMC-FT disminuidos respecto de los VU izquierdos, con FE similares. Existe correlación entre STE y RMC-FT, no equivalentes, con buena factibilidad y reproducibilidad. Conclusiones: La RMC-FT y el STE son técnicas útiles en el diagnóstico temprano y la vigilancia de la función ventricular en VU derechos con FE preservada.

Abstract Introduction: In patients with TCPC, the development of ventricular dysfunction is inevitable and is more precocious in SRVs. Myocardial deformation by STE and CMR-FT is promising. Objective: To analize ventricular function in patients with TCPC using STE and CMR-FT compared with conventional cMRI, depending on SV morphology, to determine their role in early diagnosis of ventricular dysfunction. Method: Sixty-four patients with TCPC were included. Longitudinal and circumferential strain by STE and CMR-FT and ventricular volume and EF were obtained. Results: Dysfunction analyzed by cMRI showed no association with ventricular morphology. SRVs had lower values in STE and CMR-FT compared with SLVs, with similar EF. While not equivalent, correlation was observed between the STE and the CMR-FT values, demonstrating good feasibility and reproducibility. Conclusion: The strain data in CMR-FT and STE could be useful for diagnosis and monitoring of ventricular function and as markers of early SRV dysfunction with preserved EF.

Early myocardial strain characteristics in type 2 diabetic mellitus mice evaluated by 7.0 T cardiac MR / 中华放射学杂志

Objective:To investigate the characteristics of early myocardial mechanics changes in diabetic cardiomyopathy (DCM).Method:Sixty healthy 4-week-old male C57BL/6J mice were randomly divided into the T2DM group ( n=30) and the control group ( n=30). The T2DM group was fed with high-fat diet for 4 weeks, and accepted injection of a single high-dose of streptozotocin (STZ) intraperitoneally. Finally, the model was established successfully in 23 mice. The control group was fed with a normal diet and treated with citrate buffer liquid at an equal dose as T2DM group. Then, nine mice were randomly selected from each of the two groups every 4 weeks until the end of the 24th week. Six of the nine mice were randomly selected to perform 7.0 T MR scanning after measuring blood glucose and body weight. Cine images were acquired through cardiovascular MR feature tracking (CMR-FT). The obtained parameters included the left ventricle global peak circumferential strain (LV-GPCS), left ventricle global peak radial strain(GPRS) and the ejection fraction (EF), etc. The rest three mice were sacrificed for observation of the changes of interstitial fibers and micro-vessels in myocardial tissue with Sirius red staining. One-way analysis of variance (ANOVA) and t test were used for comparison. Results:There were significant differences in blood glucose levels between the two groups during the observation period ( P<0.05). In the 4 th-24 th week, the value of GPCS in T2DM group showed a downward trend, and the difference was statistically significant ( F = 8.23, P<0.001). Compared with the control group, the value of GPCS in T2DM group was statistically significant at the 20 th and 24 th week (the 20 th week: -11.4%±2.1% in the T2DM group vs. -14.3%±1.9% in the control group, t=2.54, P=0.029;the 24 th week: -12.3%±1.7% in the T2DM group vs. -14.6%±1.8% in the control group, t=2.35 , P=0.040), while the EF value was different at the 24 th week (51%±5% in the T2DM group vs. 62%±6% in the control group, t=3.38, P=0.007). There was no significant difference in the GPRS of the T2DM mice group over time or compared with the controls ( P>0.05). Moreover, the pathological results showed that the myocardial interstitial fibers in the T2DM group had remarkably increased since the 12 th week. Conclusions:The alterations in myocardial interstitial fibers and myocardial contractility appeared early in T2DM mice. Especially, the left ventricle global peak circumferential strain value is superior to the EF value in reflecting the early changes in DCM.

A primary study of evaluating the left ventricular myocardial strain in patients with coronary heart disease by CT feature tracking / 中华放射学杂志

Objective:To explore the technical feasibility of CT feature tracking (CT-FT) technique in evaluating left ventricular myocardial strain and evaluate the change of myocardial strain in patients with coronary heart disease.Methods:Eighty-one patients with coronary heart disease (lesion group) and 33 patients with normal coronary artery (control group) matched with age and sex were collected retrospectively from the Second Affiliated Hospital of Nanchang University from April 2019 to October 2020. The lesion group was first divided into single vessel stenosis group (42 cases) and multi vessel stenosis group (39 cases) according to the number of coronary artery stenosis branches, and the global myocardial strains of the left ventricle between the groups were analyzed. Lesion site included the left anterior descending branch (LAD), right coronary artery (RCA) and left circumflex branch (LCX), respectively. According to the degree of vascular stenosis, the lesion groups were divided into normal group, mild stenosis group, moderate stenosis group and severe stenosis group. The segmental myocardial strains of the branch segment of LAD, RCA or LCX were analyzed between groups. All CCTA examinations were performed with retrospective electrocardiogram gating. CVI 42 cardiac postprocessing software was used to obtain myocardial strain parameters, including global peak longitudinal strain (GPLS), global peak circumferential strain (GPCS), global peak radial strain (GPRS), and the segmental myocardial strains of the branch segment of LAD, RCA or LCX. The segmental myocardial strains included the peak longitudinal strain (PLS), peak circumferential strain (PCS) and peak radial strain (PRS). One way ANOVA or Kruskal Wallis H test were used for multi group analysis. Results:With the increased number of coronary artery stenosis branches, the absolute value of GPLS gradually decreased. The GPLS of the control group, single vessel stenosis group and multi vessel stenosis group were -14.1%±2.7%, -11.5%±2.3% and -8.8%±2.0%, respectively. The difference of GPLS between the 3 groups or any 2 groups was statistically significant (all P<0.001). The absolute values of GPRS and GPRS in multi vessel stenosis group were significantly lower than those in control group and single vessel stenosis group (all P<0.001). There was no significant difference in GPRS or GPRS between single vessel stenosis group and control group ( P=0.083, 0.118). And there were significant differences in the segmental myocardial strains of the branch segment of LAD, RCA or LCX among 3 groups ( P<0.001). In severe stenosis group, the absolute values of PRS, PCS and PLS in LAD, RCA or LCX were significantly lower than those in moderate stenosis group, mild stenosis group and normal group (all P<0.05). In the moderate stenosis group, the absolute value of PLS in each branch segment was lower than that of the mild stenosis and normal group (all P<0.05), and there was no significant difference in any 2 other myocardial strain parameters of each branch (all P>0.05). Conclusions:CT-FT technique was feasible to evaluate left ventricular myocardial function. With the increased number or degree of coronary artery stenosis, the global and segmental myocardial strain parameters of left ventricle gradually decreased, and the longitudinal strain was more sensitive.

The reproducibility of left ventricular strain measured by CT and its agreement with speckle tracking echocardiography / 中华放射学杂志

Objective:To investigate the reproducibility of left ventricular strain assessed by CT feature tracking(CT-FT) and its correlation and agreement with speckle tracking echocardiography (STE).Methods:Thirty outpatients with suspected coronary heart disease who underwent whole cardiac cycle coronary CTA and transthoracic echocardiography within one week were prospectively enrolled in November 2019. Left ventricular volume and strain parameters were measured by CT-FT and STE, including left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), global longitudinal strain(GLS), global radial strain (GRS),and global circumferential strain(GCS). GLS included endocardial global longitudinal strain (EndoGLS) and myocardial global longitudinal strain (MyoGLS), GCS included endocardial global circumferential strain (EndoGCS) and myocardial global circumferential strain (MyoGCS). ICC was used to evaluate intra-and inter-observer differences in strain measured by CT-FT. The differences of measurements between CT-FT and STE were compared by paired-samples t test. Pearson correlation coefficient was used to analyze the correlation between CT-FT and STE measurements. Agreement between measurements of two modalities was assessed by Bland-Altman analysis. Results:There was a good consistency in EDV, ESV, EF, EndoGLS, MyoGLS, GRS, EndoGCS and MyoGCS measured by CT-FT between intra-and inter-observer (ICC was 0.775-0.964, P<0.001). There was no significant difference in EF measured by CT-FT and STE [(60.27±8.70) % and (61.22±5.64) %, P=0.443]. EndoGLS, MyoGLS, GRS and MyoGCS measured by CT-FT were (-20.47±4.01)%, (-18.06±3.75)%, (73.90±20.58) % and (-18.48±3.65)%, respectively, while the strain measured by STE were (-18.97±3.33)%, (-16.49±2.60)%, (18.56±3.06)% and (-20.26±4.45)%, respectively. The differences were statistically significant between CT-FT and STE ( t=-2.367, -2.945, 12.161, 2.459, P<0.05). The EndoGCS measured by CT-FT and STE were (-27.78±6.66)% and (-29.18±7.24)%, respectively, with no statistical significance ( P=0.223).The correlation coefficients of EndoGLS, MyoGLS, GRS, EndoGCS and MyoGCS measured by CT-FT and STE were 0.566, 0.629, 0.509, 0.606 and 0.539, respectively ( P<0.05). The average difference of EndoGLS, MyoGLS, GRS, EndoGCS and MyoGCS measured by CT-FT and STE was -1.5%, -1.6%, 55.3%, 1.4% and 1.8%, respectively, with 95% limits of agreement was -8.3%-5.3%, -7.3%-4.2%, 18.1%-92.5%, -10.7%-13.6% and -6.0%-9.5%, respectively. Conclusions:The left ventricular global strain evaluated by CT-FT was feasible, and the agreement of global strain between CT-FT and STE was good but not interchangeable. CT can be an alternative method for "one-stop" evaluation of cardiac anatomy and function in patients with poor echogenic windows and contraindications for MRI.

Myocardial remodeling assessed by MR feature tracking in hypertrophic obstructive cardiomyopathy after surgical myectomy / 中华放射学杂志

Objective:To investigate the changes of strains based on feature tracking in patients with hypertrophic obstructive cardiomyopathy (HOCM) after surgical myectomy and the potential factors that influenced post-myectomy global strains.Methods:A total of 27 patients with HOCM who underwent septal myectomy in Fuwai Hospital from June 2014 to July 2017 were retrospectively collected. They all received cardiac MR (CMR) cine acquisitions before and after surgery. Their preoperative and postoperative strain parameters, including radial strain (RS), circumferential strain (CS), and longitudinal strain (LS) of the global left ventricle, septum, and lateral wall, were assessed by feature tracking. Comparisons of pre-myectomy and post-myectomy imaging parameters were performed using paired-samples t-test or Wilcoxon matched-pairs signed-ranks test. Pearson or Spearman correlation analysis and linear regression analysis were utilized to find the correlated factors of postoperative global strains. Results:Compared with preoperative strains, postoperative global LS, septal LS, lateral RS, lateral CS, and lateral LS increased statistically (all P<0.05); postoperative global RS, global CS, and septal CS decreased (all P<0.05); no statistically significant difference was observed in septal RS ( P=0.165). Age at surgery ( r=0.428, P=0.026) and preoperative myocardial maximum ventricular wall thickness ( r=-0.587, P=0.001) were both linearly related to postoperative global RS; the further multivariate stepwise linear regressions showed that only preoperative myocardial maximum ventricular wall thickness might be correlated with postoperative global RS (adjusted R 2=0.287, P=0.002). Only myocardial maximum ventricular wall thickness was linearly related to global CS ( r=0.679, P<0.001) and global LS ( r=0.588, P=0.001), respectively; univariate linear regression revealed that preoperative myocardial maximum ventricular wall thickness might be correlated postoperative global CS (adjusted R 2=0.337, P=0.001) and postoperative global LS (adjusted R 2=0.281, P=0.003), respectively. Conclusions:Cardiac surgery definitely relieves left ventricular outflow tract obstruction and generally improves longitudinal and lateral strains, but a negative impact may occur in global and septal CS and RS. Preoperative maximum ventricular wall thickness may affect postoperative global strains.

Evaluation of left atrial function in asymptomatic dogs with chronic myxomatous mitral valve disease: two-dimensional feature-tracking echocardiography and Simpsons monoplanar methods / Avaliação da função atrial esquerda em cães assintomáticos com degeneração mixomatosa crônica de valva mitral: métodos ecocardiográficos bidimensional feature tracking e monoplanar de Simpson

The present study evaluated the volume and function of the left atrium by two-dimensional echocardiographic feature-tracking imaging (2D-FTI) and Simpson's monoplanar modeling in dogs with asymptomatic degenerative mitral valve disease (DMVD). The study consisted of 80 dogs that were divided into the following three groups: Group 1, 21 dogs (A); Group 2, 30 dogs (B1) and Group 3, 29 dogs (B2). The variable strain (contraction phase) was significantly lower in Group 3 than in Group 1 (12.92±4.54 x 16.69±5.74, p=0.014), and significant differences in the contraction strain index (CSI) were observed between all of the groups that were evaluated (1 = 46.82±8.10, 2 = 39.88±8.03, 3 = 35.25±5.64, p<0.0001). The atrial diastolic volume index (AdVi) that was measured by 2D-FTI was significantly higher in Group 3 than in Group 1 (1.31±0.95 x 0.96±0.31, p=0.038), and the atrial cardiac index (ACI) was also higher in Group 3 than in Group 1 (102.38±80.18 x 78.19±33.38, p=0.030). Atrial function was assessed by Simpson's monoplanar method, which demonstrated an increase in the left atrial systolic volume, while the contractile function decreased with an increasing disease severity (Group 1 0.21±0.06; Group 2 0.25±0.06; Group 3 0.32±0.08, p<0.0001). The intraobserver and interobserver assessments showed low to moderate variability; most of the values for the coefficient of variation for the variables that were analysed with each method were below 25%. Thus, DMVD was determined to cause an alteration in atrial function, especially in the contraction phase, and even in asymptomatic animals, and the methods of 2D-FTI echocardiography and Simpson's monoplanar evaluation are sensitive and early methods for the detection of left atrial dysfunction.(AU)

O presente estudo avaliou o volume e a função atrial esquerda obtidos por meio da ecocardiografia bidimensional feature tracking (2D-FTI) e pelo método monoplanar de Simpson em cães saudáveis e cães com DMVD assintomáticos. Foram avaliados 80 cães distribuídos em três grupos: Grupo 1, 21 cães (classe A); Grupo 2, 30 cães (classe B1) e Grupo 3, 29 cães (classe B2). A variável strain (fase de contração) foi significativamente menor no Grupo 3 que no Grupo 1 (12,92±4,54 x 16,69±5,74, p=0,014) e para a variável índice de strain de contração (CSI), houve diferença estatística entre todos os grupos avaliados (1 = 46,82±8,10; 2 = 39,88±8,03; 3 = 35,25±5,64, p<0,0001). O índice de volume diastólico atrial (iVdA) mensurado por meio do 2D-FTI foi significativamente maior no Grupo 3 que no Grupo 1 (1,31±0,95 x 0,96±0,31, p=0,038), assim como para o índice cardíaco atrial (iCA) também foi maior no Grupo 3 (102,38±80,18 x 78,19±33,38, p=0,030). A função atrial avaliada pelo método monoplanar de Simpson demonstrou um aumento do volume atrial esquerdo e do volume sistólico do átrio esquerdo, enquanto que a função contrátil diminuiu com o aumento da gravidade da doença (Grupo 1 0,21±0,06; Grupo 2 0,25±0,06; Grupo 3 0,32±0,08; p<0,0001). A avaliação intraobservador e interobservador, demonstrou variabilidade baixa a moderada, uma vez que a maioria dos valores de coeficiente de variação se concentraram abaixo de 25% para as variáveis analisadas em ambos os métodos. Dessa forma, conclui-se que a DMVD causa alteração na função atrial, principalmente na fase de contração, mesmo em animais assintomáticos e que a ecocardiografia 2D-FTI e o método monoplanar de Simpson são métodos sensíveis e precoces na detecção da disfunção atrial esquerda.(AU)

Cardiac Magnetic Resonance Feature Tracking in Aortic Stenosis: Exploration of Strain Parameters and Prognostic Value in Asymptomatic Patients with Preserved Ejection Fraction

OBJECTIVE: To determine the most valuable cardiac magnetic resonance feature tracking (CMR-FT) parameters for evaluating aortic stenosis (AS) and determine whether they can predict the prognosis in asymptomatic AS patients with preserved ejection fraction (pEF).MATERIALS AND METHODS: A prospective cohort of 123 moderate to severe AS patients (60 males, 68.6 ± 9.2 years) and 32 control subjects (14 males, 67.9 ± 4.4 years) underwent echocardiography and 3T CMR imaging from 2011–2015. CMR cine images were analyzed using CMR-FT to assess the left ventricular radial, circumferential, and longitudinal peak strain (PS) in 2- and 3-dimensions. The primary endpoints were clinical cardiac events (CCEs), including cardiac death, heart failure, and AS-associated symptom development. For statistical analysis, logistic regression and log-rank tests were used.RESULTS: Global PSs differed between AS patients and controls and between severe and moderate AS patients (p < 0.05). Two-dimensional (2D) global radial and longitudinal PSs changed gradually with the severity of AS groups (p < 0.001). Twenty-two of 67 asymptomatic AS patients with pEF experienced CCEs during the follow-up (median: 31.1 months). 2D global longitudinal PS (GLPS) was the single risk factor for CCE (p = 0.017). The relative risk for CCE was 3.9 (p = 0.016, 95% confidence interval: 1.2–11.9) based on 2D GLPS with a cutoff of −17.9% according to receiver operating characteristic curve analysis. Survival analysis demonstrated that asymptomatic AS patients with pEF having impaired 2D GLPS experienced worse event-free survival than the others (p = 0.041).CONCLUSION: 2D global longitudinal and radial PSs may reflect cardiac dysfunction according to the degree of AS. 2D GLPS might be a prognostic predictor of CCEs in asymptomatic AS patients with pEF.

Left atrial function in healthy Chinese population by cardiac magnetic resonance-feature tracking imaging: A quantitative study / 第二军医大学学报

ObjectiveTo quantitatively evaluate the left atrial function in healthy Chinese population by cardiac magnetic resonance-feature tracking (CMR-FT). MethodsHealthy individuals with normal magnetic resonance examination results were enrolled according to the inclusion criteria. Cardiac long- and short-axis images and cine were obtained using semi-Fourier single-shot technique and balanced steady-state free precession sequence. The left atrial function parameters, including left atrial volume, ejection fraction, strain and strain rate, were measured by 2 independent observers. Two independent sample t test was used to compare the parameters between males and females. One-way analysis of variance was performed to compare the parameters among different age groups. ResultsA total of 63 volunteers were included in this study. Of 63 volunteers, 34 were males and 29 females; and 19 volunteers were aged≤29 years, 23 were aged 30-44 years and 21 were aged≥45 years. The anteroposterior diameter of left atrium was (26.1±4.5) mm, and the transverse diameter was (54.8±5.9) mm. The total ejection fraction of left atrium was (63.5±6.9)%, total strain was (45.9±11.7)%, and total strain rate was (1.5±0.5) s-1. The passive ejection fraction of left atrium was (24.6±9.1)%, passive strain was (22.2±8.1)%, and passive strain rate was (-0.8±0.3) s-1. The active ejection fraction of left atrium was (51.3±8.9)%, active strain was (23.7±9.2)%, and active strain rate was (-1.3±0.5) s-1. There were significant differences in the body surface area, the left atrial diameters, maximal volume and pre-active contraction volume between the males and the females (all P0.05). There were significant differences in the left atrial conduit function among the different age groups (all P0.6, and the Bland-Altman analysis showed better consistency between the two observers. ConclusionCMR-FT can be used to obtain parameters related to left atrial function in healthy Chinese population due to its high repeatability.

MRI measurement of left ventricle myocardial strain on short axis in normal youth / 中华放射学杂志

Objective To learn the endocardial strain patterns of the left ventricles on the short-axis views in normal youth volunteers using feature tracking techniques on cine cardiac MR imaging,and to build up the reference ranges of strain peak and time to peak (TTP) for endocardial strain analysis.Methods Twenty-nine normal youth volunteers aged from 24-34 years old were enrolled in the study in march 2015.The Cine MR imaging were acquired using balance FFE sequence with 24 phases for each cardiac cycle.The standard short-axis imaging planes were basal,mid-cavity and apical levels and divided into 16 segments.The peaks and TTPs of myocardial displacement and its velocity,radial and circumferential strain and strain rate and its velocity in each segment were calculated using feature tracking techniques.The data with normal distribution were analyzed by ANOVA and Student-Newman-Keuls (SNK) method,and Kruskal-Wallis and Wilcoxon rank sum test were used for the data without normal distribution.Results The peaks and TTPs of radial strain and strain rate differed in 16-segmental levels and basal,middle and apical plane levels and had no concordant reference ranges.The circumferential strain and strain rate were homogeneous at basal and middle plane levels [(-27.09 ±9.51)％,(1.94 ±0.98)/s,respectively].Their TTPs were homogenous [0.38 (0.08)RR,0.54 (0.08)RR,respectively],and there were no significant differences in planar-segments or inter-segment level.Except for middle level,the peaks of radial displacement and velocity differed in basal and apical levels and had no concordant reference ranges.But radial velocity TTPs were homogeneous in all 16 segments [0.21 (0.04)RR].Except for the radial strain rate,TTPs showed no significant difference between basal level and middle level.The measurements at apical level revealed high variance.No regular pattern could be found on individual peak and TTP curves of velocity and strain rate.Conclusion The peaks and TTPs of radial strain are different in segmental and planar levels without a concordant reference range.The peaks and TFPs of circumferential strain and the radial velocity rTTPs are homogeneous in middle and apical plane level and have homogeneous reference range.

A preliminary study of left ventricular function assessement in patients with atrial fibrillation by MR feature tracking technique / 中华放射学杂志

Objective To explore the clinical application value of left atrial function with feature tracking cardiac magnetic resonance imaging (FT-CMR) by evaluating preliminarily left atrial strain and strain rate in patients with atrial fibrillation. Methods Thirty patients with paroxysmal atrial fibrillation, thirty patients with persistent atrial fibrillation and twenty-two healthy subjects were enrolled. All the subjects underwent cardiac magnetic resonance imaging with the real steady-state free precession(SSFP) sequence. FT-CMR parameters included left atrial strain and strain rate parameters, left atrial volume and function parameters were detected by using offline cardiovascular analysis software, respectively. Left atrial strain and strain rate parameters included left atrial total strain(Εs), passive strain(Εe), active strain(Εa), peak positive strain rate(SRs), peak early negative strain rate(SRe)and peak late negative strain rate(SRa). Volume and function parameters included maximum of left atrial volume(LAVmax), minimum of left atrial volume(LAVmin), total left atrial emptying fraction(LATEF), passive left atrial emptying fraction(LAPEF)and active left atrial emptying fraction(LAAEF). The differences in the general data among the paroxysmal atrial fibrillation group, the persistent atrial fibrillation group and the control group were compared by usingχ2 test or ANOVA analysis. The differences in all parameters between the atrial fibrillation group and the control group, the paroxysmal atrial fibrillation group and the persistent atrial fibrillation group were compared by using independent t test. Left atrial strain and strain rate parameters on an intra-observer and inter-observer were determined by intraclass correlation coefficient(ICC)analyses. Results Compared to control group, LAVmax and LAVmin in atrial fibrillation group were significantly increased(t=9.737,7.889,P<0.001);The LATEF and LAPEF had no significant difference, the LAAEF in two groups had statistically significant difference(t=-4.762,P<0.001).The absolute value of Es, Ee, Ea, SRs, SRe, SRa in atrial fibrillation group were significantly reduced than in control group(t=-7.732,-6.610,-6.493,-7.546, 6.864, 5.917,P<0.001). Compared with paroxysmal atrial fibrillation group, LAVmax and LAVmin in persistent atrial fibrillation group were increased obviously, LATEF and LAPEF were significantly decreased, and the differences were statistically significant(t=-4.575,-5.524, 4.002, 4.028,P<0.001).The LAAEF in two groups had no statistically significant difference. Compared with strain and strain rate in two groups, absolute value of Es, Ee, Ea, SRs, SRe, SRa in persistent atrial fibrillation group significantly decreased than in paroxysmal atrial fibrillation(t=4.310, 3.128, 4.465, 5.496,-3.290,-3.863,P<0.001). The intra-group and inter-group had well correlation coefficients between the observers in the left atrial strain and strain rate parameters of the subjects(ICC=0.85—0.94,0.81—0.90). Conclusions FT-CMR technique can be used to assess the left atrial strain and strain rate in patients with atrial fibrillation;Left atrial reservoir, conduit and booster-pump functions in patients with atrial fibrillation were impaired. Patients with persistent atrial fibrillation had worse left atrial function throughout the entire cardiac cycle compared with those with paroxysmal atrial fibrillation.

Correlating transmural extent of acute myocardial infarction to left ventricular stain by mrifeature tracking / 中国介入心脏病学杂志

Objective The left ventricular myocardial strain of acute myocardial infarction on cardiac magnetic resonance cine imaging was measured by feature tracking technique. The relationship between left ventricular myocardial strain and the transmural extent of Myocardial Infarction was evaluated. Methods 74 patients with acute ST segment elevation myocardial infarction were included. All theses patients received primary PCI within 12 hours. After 2 to 5 days. ECG gated steady-state free precession sequences were collected. Gadolinium contrast enhanced imaging was performed on short axis. 20 patients repeated same scan after 3 to 5 months. TomTec 2D CPA and Segment software were used to analyze the images. The peak values of the regional myocardial strain indexes. The transmural extent of myocardial infarction of segment in left ventricular was measured. Results There was no significant difference of longitudinal strain in non-infarction,non-transmural infarction and transmural infarction segments at the basal and middle segments. The circumferential strain peak and the radial strain peak of non-transmural infarction segments were lower than those of the non-infarction segments. The circumferential strain of transmural infarction segments were the lowest(basal level:-14.24％±9.05％,P<0.05;middle level:-12.71％±8.92％,P<0.05;apical level:-13.81％±11.13％, P<0.05). GLS was improved while LVDd was increased when compared the acute phase of myocardial infarction to that of 3-5 months after primary PCI. The circumferential strain and longitudinal strain of the non-transmural infarction segments was improved. The circumferential strain and radial strain of the transmural infarction segments 3-5 months later was improved as compared to the acute phase. Conclusions There was differences in myocardial strain in non-infarction,non-transmural infarction and transmural infarction segments from patients with acute ST segment elevation myocardial infarction who had accepted primary PCI. The circumferential strain and longitudinal strain of the non-transmural infarction segments were improved after 3-5 months. The circumferential strain and radial strain of the transmural infarction segments after 3-5 months was improved as compared to the acute phase. Cardiac Magnetic resonance could combine feature tracking technique with gadolinium contrast delayed enhancement technique,giving both function and tissue characteristic evaluation to the myocardial damages after acute myocardial infarction.

Cardiac MR feature tracking in detection of left ventricular myocardial strain in hypertrophic cardiomyopathy / 中国医学影像技术

Objective To explore clinical value of cardiac MRI feature tracking (CMR-FT) in evaluation of left ventricular global and regional myocardial strain in hypertrophic cardiomyopathy (HCM).Methods Totally 60 patients with HCM (HCM group) and 10 healthy volunteers (control group) were enrolled and underwent cardiac MR.MR Sequences included fast imaging employing steady state acquisition (FIESTA) and late gadalinum enhancement (LGE) at ventricular short-axis,two-chamber and four-chamber planes.The patients in HCM group were divided into LGE negative subgroup and LGE positive subgroup.CMR-FT processing software was used to measure myocardial global radial peak strain (GPSR),global circumferential peak strain (GPSC) and global longitudinal peak strain (GPSL).The radial,circumferential and longitudinal peak strain (PSR,PSC and PSL) at the apex,middle and basal parts of left ventricular were also measured as well.Resuits GPSR,GPSC,GPSL in LGE positive subgroup,LGE negative subgroup and control group had significant differences (all P＜0.05),and showed upward trends.Except PSL at the apex had no significent difference among three groups,PSR,PSC and PSL at the apex,middle and basal parts had significant differences (all P＜0.05),and also showed upward trends.There were positive correlations between the LVEF,SV and GPSR,GPSC,GPSL (all P＜0.05).The area under ROC curve of GPSR,GPSC and GPSL in diagnosis of HCM were 0.79,0.82,0.77 (all P＜0.05),and the area under ROC curve of GPSC was the largest.Conclusion The CMR-FT technology can find myocardial strain dysfunction in HCM sensitively,and the longitudinal strain is damaged earlier or worse than circumferential and radial strains.

Quantitative evaluation of myocardium deformation in patients with hypertrophic cardiomyopathy by cardiovascular magnetic resonance feature tracking / 中国医学影像技术

Objective To explore the value of cardiovascular magnetic resonance feature tracking (CMR-FT) in quantita tive evaluation of myocardium deformation in patients with hypertrophic cardiomyopathy (HCM).Methods Sixteen HCM patients (HCM group) and 18 healthy volunteers (control group) were enrolled and measured with CMR-FT.The differences of left ventricular (LV) end diastolic volume (LVEDV),LV end systolic volume (LVESV),LV ejection fraction (LVEF),left ventricular mass (LVMASS) and LV global radial strain (RS),LV global circumferential strain (CS) were compared between the two groups.The correlations between segmental wall thickness and segmental RS and CS were studied.And the correlation among global RS,CS and LVEDV,LVESV,LVEF,LVMASS were analyzed.Results LVMASS in HCM group was higher than that in control group ([133.74±79.13]g vs [76.87±14.15]g,P=0.01).No sig nificant differences of LVEDV,LVESV,LVEF were found between HCM group and control group (all P＞0.05).Global RS and CS were significantly lower in HCM group than those in control group (RS:[27.05 ± 13.35]％ vs [40.62 ± 4.92] ％,P＜0.01;CS:[-8.68± 5.56] ％ vs [-20.73 ± 1.56] ％,P＜0.01).No significant correlations was observed between segmental wall thickness and segmental RS (r=-0.41,P＜0.01),CS (r=0.28,P＜0.01),respectively.In HCM group,no significant correlations was observed between global RS (r=-0.36,-0.41,0.22,-0.36),CS (r=0.34,0.10,0.22,0.42) and LVEDV,LVESV,LVEF,LVMASS,respectively (all P＞0.05).Conclusion CMR-FT is conducive to quantitative evaluate myocardial deformation in HCM patients.