Improving the role of echocardiography in studying the right ventricle of repaired tetralogy of Fallot patients: comparison with cardiac magnetic resonance

Right ventricular (RV) evaluation represents one of the major clinical tasks in the follow-up of repaired tetralogy of Fallot patients (rToF) with pulmonary valve regurgitation, as both severe RV dilatation and dysfunction are key factors in defining the need of pulmonary valve replacement. The aim of our study was to report the diagnostic accuracy of echocardiography in the identification of rToF patients with severely dilated and/or depressed RV as compared to cardiac magnetic resonance (CMR). Among our patients with rToF, a subgroup of 95 (17.6?±?6.8 years; 60% male), who underwent right ventricular qualitative and quantitative evaluation with CMR following echocardiographic suspicion of severe dilation/dysfunction, were included in the analysis. When comparing echocardiographic RV functional parameters to CMR findings, we found no association between CMR-ejection fraction (EF) and either tricuspid annulus plane systolic excursion (TAPSe) nor tissue Doppler systolic tricuspid excursion velocity (all p?=?ns). In contrast RVFAC was strongly associated with CMR-EF (r?=?0.44; p?<?0.01) as well as to longitudinal components of RV mechanics including tissue Doppler s′ (r?=?0.40; p?<?0.01) and TAPSE (r?=?0.36; p?<?0.01). When comparing echocardiographic and CMR structural parameters of the RV, we found that CMR RV volume was strongly related to echocardiographic measurements of RV end diastolic area (from the 4 chamber apical view) and with proximal parasternal short axis right ventricle outflow-dimension. Accordingly a regression model was derived from multiple regression analysis, which allows a more accurate estimate of CMR RV volume from echocardiography (r²?=?0.59, p?<?0.001). Our study demonstrates a significant, although imperfect, correlation between echocardiographic and CMR RV functional and geometrical parameters. Combining echocardiographic measures of RV inflow and RV outflow, we deliver a simple formula to estimate CMR-RV volume, improving the echocardiographic accuracy in RV volume quantification.     

Correlation between right ventricular T<Subscript>1</Subscript> mapping and right ventricular dysfunction in non-ischemic cardiomyopathy

Right ventricular (RV) fibrosis is increasingly recognized as the underlying pathological substrate in a variety of clinical conditions. We sought to employ cardiac magnetic resonance (CMR) techniques of strain imaging and longitudinal relaxation time (T₁) mapping to better examine the relationship between RV function and structure. Our aim was to initially evaluate the feasibility of these techniques to evaluate the right ventricle. We then sought to explore the relationship between RV function and underlying fibrosis, along with examining the evolution of RV remodeling according to the amount of baseline fibrosis. Echocardiography was performed in 102 subjects with non-ischemic cardiomyopathy. Right ventricular parameters were assessed including: fractional area change (FAC) and longitudinal strain. The same cohort underwent CMR. Post-contrast T₁ mapping was performed as a marker of fibrosis with a Look-Locker technique using inversion recovery imaging. Mid-ventricular post-contrast T₁ values of the RV free wall, RV septum and lateral LV were calculated using prototype analysis software. Biventricular volumetric data including ejection fraction was measured by CMR using a cine short axis stack. CMR strain analysis was also performed to assess 2D RV longitudinal and radial strain. Simultaneous biochemical and anthropometric data were recorded. Subjects were followed over a median time of 29 months (IQR 20–37 months) with echocardiography to evaluate temporal change in RV FAC according to baseline post-contrast T₁ values. Longitudinal data analysis was performed to adjust for patient loss during follow-up. Subjects (62% men, 51?±?15 years) had mild to moderately impaired global RV systolic function (RVEF?=?39?±?15%; RVEDV?=?187?±?69 ml; RVESV?=?119?±?68 ml) and moderate left ventricular dysfunction at baseline (LVEF 30?±?17%). Good correlation was observed between mean LV and RV post-contrast T₁ values (r?=?0.652, p?<?0.001), with similar post-contrast T₁ values maintained in both the RV free wall and septum (r?=?0.761, p?<?0.001). CMR RVEF demonstrated a proportional correlation with echocardiographic measures of RV longitudinal function and CMR RV strain (longitudinal r?=??0.449, p?=?0.001; radial r?=??0.549, p?<?0.001). RVEF was related to RV post-contrast T₁ values, particularly in those with RV dysfunction (free wall T₁ r?=?0.259 p?=?0.027; septal T₁ r?=?0.421 p?<?0.001). RV strain was also related to RV post-contrast T₁ values (r?=??0.417, p?=?0.002). Linear regression analysis demonstrated strain and post-contrast T1 values to be independently associated with RVEF. Subjects with severe RV dysfunction (CMR RVEF <25%) demonstrated lower RV CMR strain (longitudinal p?=?0.018; radial p?<?0.001), RV T₁ values (free wall p?=?0.013; septum <0.001) and RV longitudinal echocardiography parameters despite no difference in afterload. During follow-up, those with RV free wall post-contrast T₁ values?≥?350 ms demonstrated ongoing improvement in FAC (Δ6%), whilst values <350 ms were associated with deterioration in RV function (ΔFAC?=??5%) (p?=?0.026). CMR provides a comprehensive method by which to evaluate right ventricular function. Post-contrast T₁ mapping and CMR strain imaging are technically feasible and provide incremental information regarding global RV function and structure. The proportional relationship between RV function and post-contrast T₁ values supports that myocardial fibrosis is a causative factor of RV dysfunction in NICM, irrespective of RV afterload. This same structural milieu also appears integral to the propensity for both positive and negative RV remodeling long-term, suggestive that this is also determined by the degree of underlying RV fibrosis.     

实时三维超声心动图评价酒精性心肌病患者右心室收缩功能

目的 应用实时三维超声心动图(RT-3DE)评价酒精性心肌病(ACM)患者右心室收缩功能的变化。方法 对30例ACM患者(ACM组)和30名正常人(对照组)分别进行常规超声及RT-3DE检查。常规超声测量参数包括左心室射血分数(LVEF)、右心室舒张末期面积(RVEDA)和收缩末期面积(RVESA),计算右心室面积变化分数(RVFAC);运用M型超声测量三尖瓣环收缩期位移(TAPSE);RT-3DE测量参数包括右心室舒张末期容积(RVEDV)、收缩末期容积(RVESV)、每搏量(RVSV)、射血分数(RVEF)。比较两组上述参数的差异,分析RVFAC、TAPSE与RVEF的相关性。结果 常规超声中,ACM组RVEDA和RVESA高于对照组,LVEF、RVFAC和TAPSE低于对照组(P均<0.05);RT-3DE中,ACM组RVEDV和RVESV高于对照组,RVEF低于对照组(P均<0.05),两组RVSV无明显差异(P>0.05)。RVFAC、TAPSE均与RVEF呈正相关(r=0.610、0.822,P均<0.05)。结论 RT-3DE能准确评价右心室收缩功能,具有一定临床应用价值。     

Right ventricular septomarginal trabeculation hypertrophy is associated with disease severity in patients with pulmonary arterial hypertension

To characterize the morphological change in the right ventricle (RV) of patients with pulmonary artery hypertension (PAH) and further explore the correlation between septomarginal trabeculation (SMT) and right ventricular (RV) function, myocardial fibrosis, and exercise capacity in patients with PAH. Sixty untreated PAH patients were prospectively included from May 2016 to April 2017. All patients underwent comprehensive clinical evaluation and cardiac magnetic resonance (CMR). The area and diameter of the basal segment of SMT, and the mass of SMT were measured on cine SSFP images. Relationship between parameters of SMT and RV ejection fraction (RVEF), 6 min walking distance (6MWD), myocardial fibrosis and pulmonary vascular resistance (PVR) were evaluated by Pearson’s correlation and logistic regression. Predictive performance of SMT parameters for reduced RVEF or impaired 6MWD was evaluated by receiver operating characteristics (ROC) analysis. Compared with SMT diameter index and mass index, SMT area index (SMT Ai) in basal segment was the best parameter to show correlation with RVEF (r?=???0.496, P?<?0.001), 6MWD (r?=???0.619, P?<?0.001), and inferior insertion point (I IP) extracelluar volume (ECV) (r?=?0.365, P?=?0.008). ROC showed that SMT Ai had the strongest predictive value for reduced RVEF (AUC?=?0.756), and impaired 6MWD (AUC?=?0.813). SMT parameters were closely correlated with RV systolic function and 6MWD in patients with PAH. SMT Ai is a simple imaging indicator for the severity of PAH.     

基于人工智能的三维超声心动图定量评估右心室功能的价值

目的探讨基于人工智能（AI）的三维超声心动图（3DE）算法在定量评估右心室（RV）功能中的价值。 方法连续性收集自2021年1月至2021年2月在华中科技大学同济医学院附属同济医院就诊且行心脏磁共振（CMR）的患者51例,CMR检查后24 h内进行3DE检查,使用基于AI的3DE软件自动分析右心室（RV）功能参数,记录每位患者所有参数值及分析时间。对RV 3DE图像质量进行分级评估（分为优、中等、差）。以CMR测量的RVEF（CMR-RVEF）为金标准,比较AI-3DE计算的RVEF与CMR结果的相关性及一致性;以CMR-RVEF＜45%为RV收缩功能减低,比较AI-3DE所获取的定量参数在RV功能正常与功能减低组间的差异,并绘制ROC曲线分析各参数对RV收缩功能异常的诊断价值。 结果51例患者均应用AI-3DE完成了RV功能的多参数定量分析,19例（19/51,37.3%）未经手动校正的患者,全自动分析平均时间为（15±1）s;32例需要手动校正的患者中,AI-3DE RV分析时间在图像质量优、中等、差的患者中分别为（100±12）、（105±6）、（162±3）s,三者比较差异有统计学意义（F=1954.9,P＜0.05）。CMR与AI-3DE测量的RVEF分别为51%（44%,54%）和47%（43%,50%）,2种方法的测值差异无统计学意义（P＞0.05）。相关性分析散点图显示,2种方法测量结果呈一定程度的正相关关系（r=0.735,P＜0.05）。Bland-Altman图表明,2种方法获得的差异分布在平均值附近,二者具有良好的一致性。基于AI-3DE的RVEF、三尖瓣环收缩期位移（TAPSE）、右心室面积变化分数（FAC）、室间隔长轴应变（LS）和RV游离壁LS在RV功能正常组与功能减低组之间差异均有统计学意义（P均＜0.05）。ROC曲线显示,基于AI-3DE的RVEF诊断RV功能减低的ROC曲线下面积为0.854,最佳截断值为43%,敏感度为94.4%,特异度为66.6%。 结论基于AI的3DE算法能够快速、准确地获得反映RV功能的多参数指标,这些定量参数尤其是RVEF对RV功能减低具有良好的诊断价值。     

Prognostic value of cardiovascular magnetic resonance derived right ventricular function in patients with interstitial lung disease

Background

Cardiovascular magnetic resonance (CMR) provides non-invasive and more accurate assessment of right ventricular (RV) function in comparison to echocardiography. Recent study demonstrated that assessment of RV function by echocardiography was an independent predictor for mortality in patients with interstitial lung disease (ILD). The purpose of this study was to determine the prognostic significance of CMR derived RV ejection fraction (RVEF) in ILD patients.

Methods

We enrolled 76 patients with ILD and 24 controls in the current study. By using 1.5 T CMR scanner equipped with 32 channel cardiac coils, we performed steady-state free precession cine CMR to assess the RVEF. RV systolic dysfunction (RVSD) was defined as RVEF ≤45.0% calculated by long axis slices. Pulmonary hypertension (PH) was defined as mean pulmonary artery pressure (mPAP) of more than 25 mmHg at rest in the setting of pulmonary capillary wedge pressure ≤15 mmHg.

Results

The median RVEF was 59.2% in controls (n = 24), 53.8% in ILD patients without PH (n = 42) and 43.1% in ILD patients with PH (n = 13) (p < 0.001 by one-way ANOVA). During a mean follow-up of 386 days, 18 patients with RVSD had 11 severe events (3 deaths, 3 right heart failure, 3 exacerbation of dyspnea requiring oxygen, 2 pneumonia requiring hospitalization). In contrast, only 2 exacerbation of dyspnea requiring oxygen were observed in 58 patients without RVSD. Multivariate Cox regression analysis showed that RVEF independently predicted future events, after adjusting for age, sex and RVFAC by echocardiography (hazard ratio: 0.889, 95% confidence interval: 0.809 – 0.976, p = 0.014).

Conclusions

The current study demonstrated that RVSD in ILD patients can be clearly detected by cine CMR. Importantly, low prevalence of PH (17%) indicated that population included many mild ILD patients. CMR derived RVEF might be useful for the risk stratification and clinical management of ILD patients.     

实时三维超声心动图评价右室收缩功能的初步临床研究

目的 应用实时三维超声心动图(RT-3DE)检测右室收缩功能,并与传统二维超声心动图对照,探讨该技术的可行性与准确性。方法 使用RT-3DE系统采集32例健康志愿者的右室“金字塔”型数据库,结合容积分析软件,采用心尖八平面法勾勒右室舒张末期容积(RVEDV)和收缩末期容积(RVESV),并计算右室每搏量(RVsV)和射血分数(RVEF);同时在M型超声心动图上测量右室游离壁三尖瓣环处的收缩期位移(TASE)、二维超声心动图上勾画右室面积变化分数(FAC),比较三维容积法测定的收缩指数与TASE、FAC间的相关性。结果 RT-3DE测量的RVSV、RVEF均与TASE呈显著正相关(r=0．90;r=0．83);RVEF与FAC之问呈正相关(r=0．63)。结论 实时三维超声容积成像能快速简便、准确无创地确定右室容积,为临床早期评估右心收缩功能提供了有力手段,具有极其广阔的发展前景。     

实时三维超声心动图在三尖瓣下移畸形矫治术后右室重构评估中的应用

目的：探讨实时三维超声心动图（three-dimensional echocardiography,3DEcho）在三尖瓣下移畸形（Ebstein anomaly,EA）解剖矫治术后右室重构评估中的应用。 方法：回顾性分析2015年10月至2022年08月期间在中国医学科学院阜外医院住院行外科矫治术治疗的22例EA患者临床资料、3DEcho及心脏磁共振（cardiac magnetic resonance,CMR）指标。 结果：患者中位年龄30.7（14.1, 38.4）岁,中位随访时间22.9（6.5,35.6）月。3DEcho与CMR两种检查方法在基线右室舒张末容积指数（indexed right ventricular end-diastolic volume, RVEDVi）指标测值呈高度正相关(r = 0.908, P = 0.012);基线右室射血分数（right ventricular ejection fraction, RVEF）(r = 0.621, P = 0.002)、术后RVEF (r = 0.567, P = 0.009) ,两者测值均呈中度正相关,有统计学意义。术后与术前基线状态相比较,三尖瓣反流程度减轻【术后反流程度≥中度者3例（13.6%）vs.术前≥中度者20例（90.9%）,P<0.01】,RVEDVi较术前减小（98.4±54.8 vs. 188.5±114.5 ml/m2, P<0.01）,差异有统计学意义;术后整组RVEF变化无统计学意义（术后 41.2±7.9% vs. 术前44.6±6.7%, P=0.215）。 结论：3DEcho可准确评估EA患者右室容积及功能,并在术后随访评估右室重构中发挥重要作用。     

超声心动图评价肺动脉血栓内膜剥脱术的近期疗效

目的 应用超声心动图观察慢性血栓栓塞性肺动脉高压患者右心功能改变情况,以评价肺动脉血栓内膜剥脱术(PTE)的近期疗效.方法 慢性血栓栓塞性肺动脉高压患者16例,于PTE术前及术后15d、30d分别测量左室舒张末期内径(LVDd)、右室舒张末期面积(RVEDA)、右室收缩末期面积(RVESA)、右室面积变化率(RVFAC)、肺动脉血流加速时间(Pact)、三尖瓣反流压差(PGT1)及三尖瓣反流面积(AT1).结果 16例患者PTE后15 d、30 d的LVDd、Pact较术前增加.RVEDA、RVESA、PGT1、AT1均减小,RVFAC增大(均P<0.01).结论 PTE可以有效缓解慢性血栓栓塞性肺动脉高压患者的肺动脉压力,改善右心功能.     

实时三维超声心动图评价系统性红斑狼疮并发肺动脉高压患者右心功能

目的 采用实时三维超声心动图(RT-3DE)和传统二维超声心动图综合评价系统性红斑狼疮(SLE)并发肺动脉高压(PAH)患者右心结构和功能.方法 获得60例SLE患者(无PAH亚组、轻度PAH亚组、中重度PAH亚组)和28名健康对照者(对照组)右心常规超声和三维全容积超声动态图像,测量常规右心结构、功能和血流动力学参数;采用三维分析软件获得右心室舒张末期容积指数(RVEDVI-3D)和收缩末期容积指数(RVESVI-3D),射血量(RVSV-3D)、射血分数(RVEF-3D),比较其在各组间的差异,分析各参数间的相关性.结果 中重度PAH亚组RA长短轴内径、RV乳头肌部和基底部内径明显增大,RVEDVI-2D和RVESVI-2D明显增大,RVEF-2D明显降低,差异均有统计学意义(P均 <0.05);不同组间RVFAC、RVTei指数、RV e/a差异均有统计学意义(P均 <0.05);中重度PAH亚组TAPSE、s明显降低,E/e明显增大,差异均有统计学意义(P均 <0.05).中重度PAH亚组RVEDVI-3D和RVESVI-3D明显增大,RVEF-3D和RVSV-3D明显降低,差异均有统计学意义(P均 <0.05).三尖瓣环收缩期位移(TAPSE)、s、RVFAC分别与肺动脉收缩压呈负相关(P均 <0.001).RV Tei指数分别与PVR、肺动脉收缩压、平均压呈正相关(P均 <0.001).RVEDVI-3D、RVESVI-3D分别与PVR、肺动脉收缩压、平均压呈正相关(P均 <0.05).RVEF-3D与s、TAPSE分别呈正相关(P均 <0.001).RVEDVI-3D、RVESVI-3D分别与RVTei指数呈正相关(P均 <0.001).RVEDVI-3D、RVESVI-3D分别与s呈负相关(P均 <0.05).结论 RT-3DE可在机、快速、定量分析SLE患者RV容积和功能,适于临床应用.     

Three-dimensional full automated software in the evaluation of the left ventricle function: from theory to clinical practice

Left ventricular systolic function evaluation is an essential part of all transthoracic echocardiographic (TTE) studies. 3D echocardiography (3DE) is superior to 2D and is recommended as the method of choice. However, since it is time consuming and requires training, it is rarely performed. Different automatic analysis software tries to overcome these limitations but they need to be accurate and reproducible before they can be used clinically. The aim of this study was to test the accuracy and reproducibility of new 3D automatic quantitative software in everyday clinical practice. 69 patients referred to our Echo Lab for a clinically indicated echocardiographic examination were included. All patients underwent a full TTE with 3D image acquisition. Left ventricular volumes and ejection fraction (LVEF) were obtained using Heart Model software, and compared with conventional 3D volumetric data. Automated analysis was performed using three different sliders setting, with or without regional editing if necessary. 20 patients underwent a cardiac magnetic resonance (CMR) study the same day of the echo and automated measurements were also compared with a CMR reference. Intra- and inter-technique comparisons including linear regression with Pearson correlation coefficients and Bland–Altman analyses were calculated. Mean age of the patients was 59 years, with 49.3% male. The automated 3DE model demonstrated excellent correlation with the conventional 3DE measurements of LVEF, using three different sliders settings (r?=?0.906; r?=?0.898 and r?=?0.940). Correlations with CMR values were very good as well (r?=?0.888; r?=?0.869; r?=?0.913). Similarly, no significant differences were noted between the values of EDV and ESV, measured with the automated model or CMR, with excellent correlation (EDV: r?=?0.892, r?=?0.842, 0.910; ESV: r?=?0.925, r?=?0.860, r?=?0.907). Finally, volumes calculated with the automated software were significantly greater than those obtained manually, but they showed a very good correlation (EDV: r?=?0.875, r?=?0.856, r?=?0.891; ESV: r?=?0.929, r?=?0.879, r?=?949). 3D automatic software for LV quantification is feasible and shows excellent correlations with both CMR and 3D echocardiography, considered the gold standard. No clinically relevant differences were noted when applying different border settings. This technique holds promise to facilitate the integration of 3D TTE into clinical practice.     

Cardiac MRI assessment of the right ventricle pre-and post-kidney transplant

Worsening renal function in chronic kidney disease correlates with worsening right ventricular (RV) systolic function. We evaluated the association between kidney transplantation (KT) and RV structure and systolic function, and the relationships between RV and left ventricular (LV) changes, blood pressure, and specific cardiac biomarkers, in patients with end-stage kidney disease using cardiac magnetic resonance imaging (CMR). In this prospective, multi-centre, cohort study, 39 adult patients on dialysis receiving KT and 42 patients eligible for, but not yet receiving KT, were recruited. CMR was performed at baseline, and repeated at 12 months. Among 81 patients (mean age 51 years, 30% female), RV end-diastolic volume index (RVEDVi), end-systolic volume index (RVESVi), mass index (RVMi), and ejection fraction (RVEF) did not change significantly within either the dialysis or KT group over 12 months (all p?≥?0.10). There were no significant differences in the 12-month changes of these parameters between the dialysis and KT groups (all p?≥?0.10). RVMI demonstrated positive correlations with NT-proBNP and systolic blood pressure, but not GDF-15, at baseline and at 12 months. Changes in RVEDVi, RVESVi, and RVEF were positively correlated with changes in LVEDVi, LVESVi, and LVEF, respectively over 12 months (Spearman r?=?0.72, 0.52, and 0.41; all p?<?0.001), but not mass index (Spearman r?=?0.20, p?=?0.078). In conclusion, there were no significant changes in RV mass, volumes, or systolic function 12 months after KT, as compared with continuation of dialysis. The associations between RV and LV remodeling may suggest similar underlying pathophysiologic mechanisms.

     

Placement considerations for measuring thermodilution right ventricular ejection fractions

BACKGROUND AND METHODS: Clinical examination of right ventricular (RV) performance has been hampered by the inability to measure easily RV volumes and ejection fraction. This study was performed to examine the effects of catheter position on thermodilution RVEF measurements. Six pigs (80 to 100 kg) were instrumented with an RV thermodilution catheter in the pulmonary artery, an injectate catheter in the right atrium, an atrial pacing electrode, and a systemic arterial catheter. RVEF measurements were determined using thermodilution in two ways: a) with incremental increases in pulmonary valve to thermistor distance; and b) with incremental increases in injectate port to tricuspid valve distance. These measurements were obtained at a paced rate of 102 +/- 2 beats/min and then repeated with pacing-induced tachycardia (140 beats/min). RESULTS: There was no significant difference in thermodilution RVEF measurements with the thermistor positioned 0 to 10 cm from the pulmonary valve at either heart rate. A significant reduction in RVEF occurred with the injection port located 5 to 7 cm proximal to the tricuspid valve, with this decrease becoming more pronounced during tachycardia. CONCLUSIONS: These results demonstrate that RVEF measurements can be reliably obtained using thermodilution. In these large hearts, thermodilution RVEF measurements appear to be independent of thermistor position within the pulmonary artery. However, large distances from injectate port to tricuspid valve reduced RVEF measurements.     

TAPSE联合Tei指数评价Ebstein畸形手术前后右室功能

目的:阐明三尖瓣环收缩期位移(TAPSE)联合Tei指数对Ebstein畸形(EA)患者手术前后右心功能评价的可行性。方法:本研究中人选的40例EA患者和20名健康对照者均完成了超声心动图(UCG)检查评估右心功能,其中EA患者分别于术前、术后I周、术后3月进行UCG。于四腔心切面测量常规超声心动指标,测量三尖瓣环收缩期位移(TAPSE),留取组织多普勒(TDI)四腔心切面,并计算出右心室心肌做功(RVTei)指数。结果:术前反映右心室收缩功能的TAPSE、右心室面积变化分数(RVFAC)指标降低,同时反映右心室收缩和舒张功能的RVTei指数升高。EA患者矫治术后1周、3月时TAPSE值高于术前(P<0.01),而RVTei指数低于术前(P<0.05),研究结果表明可通过TAPSE、RVTei评估EA矫治术后右心功能。TAPSE与RVFAC有一定的相关性,RVFAC在用于EA矫治手术前后右心功能的评估中,不适于术后与术前的比较,仅适于术后不同阶段之间的比较。结论;利用TAPSERVTei指数,可评估EA患者术前术后右心室功能,并认识到三尖瓣修复对右心功能改善的积极作用,为右心功能的评估积累经验。     

Three-dimensional analysis of interventricular septal curvature from cardiac magnetic resonance images for the evaluation of patients with pulmonary hypertension

Although abnormal septal motion is a well-known sign of increased pulmonary arterial pressures, it is not routinely used to quantify the severity of pulmonary hypertension (PH). This determination relies on invasive measurements or Doppler echocardiographic estimation of right ventricular (RV) pressures, which is not always feasible or accurate in patients with PH. We hypothesized that dynamic 3D analysis of septal curvature from cardiac magnetic resonance (CMR) images may reveal differences between patients with different degrees of PH. Forty-four patients (14 controls; 30 PH patients who underwent right heart catheterization) were studied using CMR and echocardiography. CMR imaging was performed using Philips 1.5T scanner with a phased-array cardiac coil, in a retrospectively gated steady-state free precession cine mode at 30 frames per cardiac cycle. Patients were divided into 3 subgroups according to pulmonary arterial pressure. CMR images were used to reconstruct dynamic 3D left ventricular endocardial surfaces, which were analyzed to calculate septal curvature throughout the cardiac cycle. 3D curvature analysis was feasible in 88% patients. Septal curvature showed different temporal patterns in different groups. Curvature values progressively decreased with increasing severity of PH, and correlated well with invasive pressures (r-values 0.78-0.79), pulmonary vascular resistance (r = 0.83) and Doppler-derived RV peak-systolic pressure (r = 0.75). 3D analysis of septal curvature from CMR images may become a useful component in the CMR examination in patients with known or suspected PH.     

Agreement of tricuspid annular systolic excursion measurement between transthoracic and transesophageal echocardiography in the perioperative setting

Objective

The aim of our study was to evaluate the level of agreement between tricuspid annular plane systolic excursion (TAPSE) measured by transthoracic echocardiography (TTE) and TAPSE measured using transesophageal echocardiography (TEE) in anesthetized patients.

Materials and methods

Thirty patients scheduled for elective cardiac surgery were prospectively studied. Shortly after induction of anesthesia before the operation, TAPSE was measured by TTE using M-mode in apical 4chamber view (4CH) and by TEE in six different views: using 2D echocardiography in midesophageal (ME) 4CH view, using M-mode in deep transgastric right ventricle (dTG RV) view at 0° and dTG RV longaxis view (LAX) as well as using anatomical M-mode (AM-mode) in ME 4CH, dTG RV at 0° and dTG RV LAX views.

Results

Bland–Altman analysis showed a good agreement for TAPSE measured using M-mode in TTE and using AM-mode in TEE in the ME 4CH and dTG RV at 0° views (?2.5?±?18 and ?2.2?±?14% respectively). The agreement between TAPSE measured in TTE and TEE using 2D in ME 4CH, using M-mode in dT GRV 0° and using M-mode and AM-mode in dTG RV LAX view showed a significant systematic underestimation of the measurements (?8.8?±?21, ?8.8?±?24, ?17.8?±?28 and ?6.4?±?20%).

Conclusion

Our study showed that the right ventricular function can be accurately and precisely estimated using TAPSE measurement by TEE in the midesophageal four chamber and deep transgastric right ventricle view at 0° using anatomical M-mode.

     

The ventricular residence time distribution derived from 4D flow particle tracing: a novel marker of myocardial dysfunction

4D flow cardiac magnetic resonance (CMR) imaging allows visualisation of blood flow in the cardiac chambers and great vessels. Post processing of the flow data allows determination of the residence time distribution (RTD), a novel means of assessing ventricular function, potentially providing additional information beyond ejection fraction. We evaluated the RTD measurement of efficiency of left and right ventricular (LV and RV) blood flow. 16 volunteers and 16 patients with systolic dysfunction (LVEF?<?50%) underwent CMR studies including 4D flow. The RTDs were created computationally by seeding virtual ‘particles’ at the inlet plane in customised post-processing software, moving these particles with the measured blood velocity, recording and counting how many exited per unit of time. The efficiency of ventricular flow was determined from the RTDs based on the time constant (RTDc?=???1/B) of the exponential decay. The RTDc was compared to ejection fraction, T1 mapping and global longitudinal strain (GLS). There was a significant difference between groups in LV RTDc (healthy volunteers 1.2?±?0.13 vs systolic dysfunction 2.2?±?0.80, p?<?0.001, C-statistic?=?1.0) and RV RTDc (1.5?±?0.15 vs 2.0?±?0.57, p?=?0.013, C-statistic?=?0.799). The LV RTDc correlated significantly with LVEF (R?=???0.84, P?<?0.001) and the RV RTDc had significant correlation with RVEF (R?=???0.402, p?=?0.008). The correlation between LV RTDc and LVEF was similar to GLS and LVEF (0.926, p?<?0.001). The ventricular residence time correlates with ejection fraction and can distinguish normal from abnormal systolic function. Further assessment of this method of assessment of chamber function is warranted.     

Right ventricular ejection fraction is better reflected by transverse rather than longitudinal wall motion in pulmonary hypertension

Background

Longitudinal wall motion of the right ventricle (RV), generally quantified as tricuspid annular systolic excursion (TAPSE), has been well studied in pulmonary hypertension (PH). In contrast, transverse wall motion has been examined less. Therefore, the aim of this study was to evaluate regional RV transverse wall motion in PH, and its relation to global RV pump function, quantified as RV ejection fraction (RVEF).

Methods

In 101 PH patients and 29 control subjects cardiovascular magnetic resonance was performed. From four-chamber cine imaging, RV transverse motion was quantified as the change of the septum-free-wall (SF) distance between end-diastole and end-systole at seven levels along an apex-to-base axis. For each level, regional absolute and fractional transverse distance change (SFD and fractional-SFD) were computed and related to RVEF. Longitudinal measures, including TAPSE and fractional tricuspid-annulus-apex distance change (fractional-TAAD) were evaluated for comparison.

Results

Transverse wall motion was significantly reduced at all levels compared to control subjects (p < 0.001). For all levels, fractional-SFD and SFD were related to RVEF, with the strongest relation at mid RV (R² = 0.70, p < 0.001 and R² = 0.62, p < 0.001). For TAPSE and fractional-TAAD, weaker relations with RVEF were found (R² = 0.21, p < 0.001 and R² = 0.27, p < 0.001).

Conclusions

Regional transverse wall movements provide important information of RV function in PH. Compared to longitudinal motion, transverse motion at mid RV reveals a significantly stronger relationship with RVEF and thereby might be a better predictor for RV function.     

二维斑点追踪技术评价心力衰竭患者右心室功能

目的 采用二维斑点追踪成像（2D-STI）评估心力衰竭（HF）患者右心室（RV）功能。方法 对31例射血分数下降型HF患者（HFREF组）、41例射血分数保留型HF患者（HFPEF组）及26名健康志愿者（对照组）行彩色多普勒超声检查,于心尖四腔心切面图像获得常规超声参数：RV壁厚度、RV基底段内径（RVD1）、RV收缩末期面积（RVESA）、RV舒张末期面积（RVEDA）、面积变化分数（RVFAC）、三尖瓣环收缩峰值速度（S''）、心肌做功指数（MPI）、三尖瓣环收缩期位移（TAPSE）及左心室射血分数（LVEF）;应用2D-STI技术获得RV游离壁基底段应变（RVLSbas）、中间段应变（RVLSmid）、心尖段应变（RVLSapi）及整体应变（RVLSfw）。比较3组间二维应变参数,分析RVLSfw与常规超声参数的相关性。结果 3组间RV壁厚度、RVD1、MPI、RVFAC、TAPSE及LVEF差异均有统计学意义（P均<0.01）。对照组、HFPEF组及HFREF组间RVLSbas、RVLSmid、RVLSfw均逐渐降低（P均<0.05）。HF患者RVLSfw与LVEF、TAPSE、MPI及RV壁厚度均呈强相关（r=-0.68、-0.53、0.52、0.51,P均<0.01）,与RVD1、FAC、S''均呈弱相关（r=0.42、-0.46、-0.39,P均<0.01）。结论 二维应变参数可用于评估HF患者RV功能。     

Assessment of the right ventricle with cardiovascular magnetic resonance at 7 Tesla

Background

Functional and morphologic assessment of the right ventricle (RV) is of clinical importance. Cardiovascular magnetic resonance (CMR) at 1.5T has become gold standard for RV chamber quantification and assessment of even small wall motion abnormalities, but tissue analysis is still hampered by limited spatial resolution. CMR at 7T promises increased resolution, but is technically challenging. We examined the feasibility of cine imaging at 7T to assess the RV.

Methods

Nine healthy volunteers underwent CMR at 7T using a 16-element TX/RX coil and acoustic cardiac gating. 1.5T served as gold standard. At 1.5T, steady-state free-precession (SSFP) cine imaging with voxel size (1.2x1.2x6) mm³ was used; at 7T, fast gradient echo (FGRE) with voxel size (1.2x1.2x6) mm³ and (1.3x1.3x4) mm³ were applied. RV dimensions (RVEDV, RVESV), RV mass (RVM) and RV function (RVEF) were quantified in transverse slices. Overall image quality, image contrast and image homogeneity were assessed in transverse and sagittal views.

Results

All scans provided diagnostic image quality. Overall image quality and image contrast of transverse RV views were rated equally for SSFP at 1.5T and FGRE at 7T with voxel size (1.3x1.3x4)mm³. FGRE at 7T provided significantly lower image homogeneity compared to SSFP at 1.5T. RVEDV, RVESV, RVEF and RVM did not differ significantly and agreed close between SSFP at 1.5T and FGRE at 7T (p=0.5850; p=0.5462; p=0.2789; p=0.0743). FGRE at 7T with voxel size (1.3x1.3x4) mm³ tended to overestimate RV volumes compared to SSFP at 1.5T (mean difference of RVEDV 8.2±9.3ml) and to FGRE at 7T with voxel size (1.2x1.2x6) mm³ (mean difference of RVEDV 9.3±8.6ml).

Conclusions

FGRE cine imaging of the RV at 7T was feasible and provided good image quality. RV dimensions and function were comparable to SSFP at 1.5T as gold standard.