Contemporary multimodality non-invasive cardiac imaging protocols for tetralogy of Fallot.

Tetralogy of Fallot is the most prevalent cyanotic congenital heart disease, requiring lifelong multimodality non-invasive cardiac imaging, such as echocardiography, cardiothoracic computed tomography, and cardiac magnetic resonance imaging. As imaging techniques continuously evolve and are gradually integrated into clinical practice, there is a critical need to update multimodality imaging protocols. Over the last two decades, cardiothoracic computed tomography imaging techniques have advanced remarkably, significantly enhancing its role in evaluating patients with tetralogy of Fallot. In this review, we describe contemporary multimodality non-invasive cardiac imaging protocols for tetralogy of Fallot, emphasizing the expanding role of cardiothoracic computed tomography. Additionally, we present standardized reporting forms designed to facilitate the clinical adoption of these protocols.

Feasibility of Cardiac Computed Tomography for the Evaluation of Ventricular Function in Postoperative Children With Congenital Heart Disease: Comparison With Cardiac Magnetic Resonance Imaging.

OBJECTIVE: We explored the feasibility of cardiac computed tomography (CCT) to evaluate postoperative ventricular function in children with congenital heart disease (CHD) and evaluated the accuracy and reproducibility of CCT using cardiac magnetic resonance (CMR) as a reference. METHODS: Thirty-two postoperative children with CHD (20 boys and 12 girls) who underwent CMR and CCT were enrolled. Left and right ventricular ejection fraction, end-diastolic volume, end-systolic volume, stroke volume, and cardiac index were measured using cardiac function analysis software. Cardiac function data were compared between CMR and CCT. The agreement between the 2 modalities was assessed using a Bland-Altman analysis. Intraclass correlation coefficients were used to assess intraobserver and interobserver reproducibility in CCT functional measurements. RESULTS: All functional parameters showed no significant difference (P > 0.05) and were well-correlated (r > 0.5, P < 0.05) between CMR and CCT. The mean values of all ventricular function parameters in CCT were higher compared with CMR. As indicated by 95% limits of agreement, left ventricular function parameters showed a better level of agreement compared with right ventricular function parameters between the 2 modalities. Intraobserver and interobserver reproducibility were excellent in CCT measurements for all functional parameters (intraclass correlation coefficient > 0.9). CONCLUSIONS: Compared with the criterion standard of CMR, CCT is feasible for assessing postoperative ventricular function with sufficient diagnostic accuracy and reproducibility in children with CHD. In addition to its important role regarding anatomical characterization, CCT is a suitable alternative and convenient follow-up tool that can be used to functional evaluation in children who are intolerant with CMR or have contraindications to CMR.

Right and left ventricular interactions, strain, and remodeling in repaired pulmonary stenosis patients with preserved right ventricular ejection fraction: A cardiac magnetic resonance study.

BACKGROUND: Right ventricular dilation and dysfunction is a common long-term complication in patients with repaired pulmonary stenosis (rPS). Additionally, abnormal right and left ventricular interactions have been reported in right-sided heart defect after intervention, including in pulmonary stenosis. PURPOSE: To analyze ventricular strain, remodeling, and left and right ventricular interactions in rPS patients with preserved right ventricular ejection fraction (RVEF) compared with healthy children using cardiac magnetic resonance. STUDY TYPE: A cross-sectional study. POPULATION: In all, 34 rPS patients and 10 healthy children volunteers (controls). FIELD STRENGTH/SEQUENCE: 3.0T/2D balanced steady-state free precession (2D b-SSFP) cine, late gadolinium enhancement (LGE), and 2D phase contrast (2D-PC). ASSESSMENT: Pulmonary regurgitation (PR) fractions of the main pulmonary artery, biventricular volumes, masses, function, and cardiac strain. STATISTICAL TESTS: Mann-Whitney U-test, t-test, Pearson correlation coefficients, Spearman's correlation coefficients, and intraclass correlation coefficients analysis were performed. RESULTS: For group analysis, the right ventricular (RV) global circumferential strain and radial strain were significantly increased in patients when compared with controls (-13.57 ± 2.69 vs. -5.91 ± 3.16, P < 0.001; 25.31 ± 8.12 vs. 9.87 ± 5.32, P < 0.001, respectively). The fraction of PR displayed moderate correlation with right ventricular end-diastolic volume index (RVEDVi) (r = 0.452, P = 0.022). RVEDVi and mass index were larger in patients vs. control (104.92 ± 27.46 vs. 85.15 ± 11.98, P = 0.016; 18.28 ± 4.95g/m2 vs. 11.67 ± 2.14 g/m2 , P < 0.001, respectively). Patients presented with preserved left ventricular ejection function, but was lower than healthy controls (60.89% ± 4.89% vs. 65.95% ± 4.56%, P = 0.006). Regional circumferential strain of segment 3 of left ventricle (LV) were significantly decreased in patients (-7.79 ± 6.52 vs. -13.56 ± 3.22, P = 0.003). DATA CONCLUSION: Compensated increased RV strain, myocardial remodeling of RV, and adverse right and left ventricular interactions occur in rPS patients with preserved RVEF. The decreased interventricular septum strain may lead to impaired LV function due to RV dilation as a result of PR. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2020;52:129-138.

Diagnostic accuracy of multi-slice computed tomography in children with Abernethy malformation.

BACKGROUND: Abernethy malformation is a rare congenital abnormality. Imaging examination is an important method for the diagnosis. The purpose of this study was to demonstrate manifestations of multi-slice computed tomography (MSCT) in Abernethy malformation and its diagnostic accuracy. METHODS: Fourteen children with Abernethy malformation were admitted to our center in China between July 2011 and January 2018. All 14 patients (eight males and six females) received MSCT and digital subtraction angiography (DSA) while eight patients also received ultrasound. The patients' age ranged from 1 to 14 (median age 8 years old). The clinical records of the patients were retrospectively reviewed. MSCT raw data were transferred to an Advantage Windows 4.2 or 4.6 workstation (General Electric Medical Systems, Waukesha, WI). We compared the findings of MSCT with DSA and surgical results in order to ascertain diagnostic accuracy. RESULTS: Three cases had type Ib Abernethy malformation and eleven cases had type II. Two cases of type II Abernethy malformation were misdiagnosed as type Ib using MSCT. Comparing the findings of MSCT with DSA and surgical results, the accuracy of MSCT was 85.7% (12/14), in which 100.0% (3/3) were type Ib and 81.8% (9/11) were type II. Clinical information included congenital heart disease, pulmonary hypertension, diffuse pulmonary arteriovenous fistula, abnormal liver function, hepatic nodules, elevated blood ammonia, and hepatic encephalopathy. Eleven cases were treated after diagnosis. One patient with Abernethy malformation type Ib (1/3) underwent liver transplantation. Seven patients with Abernethy malformation type II (7/11) were treated by shunt occlusion, received laparoscopy, or were treated with open surgical ligation. Another three patients (3/11) with Abernethy malformation type II were treated by interventional portocaval shunt occlusion under DSA. CONCLUSION: MSCT attains excellent capability in diagnosing type II Abernethy malformation and further shows the location of the portocaval shunt. DSA can help when it is hard to determine diagnosis between Abernethy type Ib and II using MSCT.

Assessment of right ventricular systolic function in children with repaired tetralogy of Fallot by multiple-view from single acoustic window with speckle tracking echocardiography.

BACKGROUND: Challenges remain in quantitative evaluation of right ventricular (RV) function by echocardiography. Multiple-view assessment is believed to provide a more comprehensive quantification of RV function than conventional single-view analysis. Peak systolic longitudinal RV strain (RVLS) measured by speckle tracking echocardiography (STE) has clinical and prognostic value. No study has investigated RV systolic function in the repaired tetralogy of Fallot (rTOF) using a standardized four-view iRotate model from one apical view. Herein, we examined the feasibility and accuracy of the four-view analysis from apical window in quantitation of RVLS among children with rTOF. METHODS: Thirty-seven children with rTOF and 37 age- and gender-matched controls were prospectively enrolled. Tricuspid annular plane systolic excursion (TAPSE) and tricuspid annular peak systolic velocity (TDI-S' ) and fractional area change(FAC) were obtained. RVLS of four free-walls were analyzed by dedicated RV speckle tracking software. Echocardiographic parameters were compared with the right ventricular ejection fraction (RVEF) measured by the cardiac magnetic resonance (CMR) in children with rTOF. RESULTS: Multi-view RVLS analysis from apical window was feasible in 35 children with rTOF and all the controls. Compared with age- and gender-matched controls, RVLS of the anterior, lateral, inferior-a, and inferior-b walls were significantly reduced in children with rTOF (P < 0.001). RVLS of the anterior, lateral, inferior-a, and inferior-b walls correlated well with CMR-RVEF in children with rTOF (r = -0.667, -0.743, -0.808, -0.695, P < 0.001). CONCLUSIONS: Multi-view analysis of RVLS from apical window can be applied to evaluate the RV function in children with rTOF. RVLS of the inferior wall-a in the aortic view is a novel and accurate indicator of RV function because of its good reproducibility and strong correlation with CMR-RVEF.

Multislice Computed Tomography Assessment of Tracheobronchial Patterns in Partial Anomalous Left Pulmonary Artery.

OBJECTIVE: The aim of this study was to present relationship between partial anomalous left pulmonary artery (PALPA) and the tracheobronchial tree and patterns of the tracheobronchial tree assessed by multislice computed tomography (MSCT). METHODS: Nine patients were assessed by MSCT. The relationships between the tracheobronchial tree and PALPA and different tracheobronchial patterns, location of tracheobronchial stenosis, severity of stenosis, and associated cardiac defects were evaluated. The results of MSCT for these patients were compared with the operative findings. RESULTS: The anatomy of PALPA was clearly identified by MSCT in all 9 patients. Three relationships between PALPA and the tracheobronchial tree were noted. In addition, 3 patterns of tracheobronchial tree anatomy were also demonstrated. The PALPA arose from the right pulmonary artery, forming a pulmonary sling (n = 2). The PALPA, which arose from the proximal right pulmonary artery, went below the tracheal bifurcation and passed anterior (n = 1) or inferior-anterior (n = 6) to the proximal left main bronchus. Three patterns of the tracheobronchial tree were presented with normal (n = 5), normal pattern with right tracheal bronchus (n = 3), and bridging bronchus (n = 1). The rate of tracheobronchial stenosis was 56% (5/9).Five patients underwent operation, and at that time, the relationship between PALPA and the tracheobronchial tree defined on MSCT was confirmed. CONCLUSIONS: The PALPA can be associated with tracheobronchial anomalies and airway compression depending on its orientation to the airway. Noninvasive imaging modalities such as MSCT will be helpful for making further management decisions.

Feasibility of three-dimensional ultrashort echo time magnetic resonance imaging at 1.5 T for the diagnosis of skull fractures.

OBJECTIVES: To investigate the feasibility of ultrashort echo time (UTE) magnetic resonance imaging (MRI) for the diagnosis of skull fractures. METHODS: The skull fracture models of ten Bama pigs and 364 patients with craniocerebral trauma were subjected to computed tomography (CT), UTE and conventional MRI sequences. The accuracy of UTE imaging in skull fracture diagnosis was analysed using receiver operating characteristic (ROC) curve analysis, McNemar's test and Kappa values. Differences among CT, UTE imaging and anatomical measurement (AM) values for linear fractures (LFs) and depressed fractures (DFs) were compared using one-way ANOVA and a paired-samples t-test. RESULTS: UTE imaging clearly demonstrated skull structures and fractures. The accuracy, validity and reliability of UTE MRI were excellent, with no significant differences between expert readings (P > 0.05; Kappa, 0.899). The values obtained for 42 LFs and 13 DFs in the ten specimens were not significantly different among CT, UTE MRI and AMs, while those obtained for 55 LFs and ten DFs in 44 patients were not significantly different between CT and UTE MRI (P > 0.05). CONCLUSIONS: UTE MRI sequences are feasible for the evaluation of skull structures and fractures, with no radiation exposure, particularly for paediatric and pregnant patients. KEY POINTS: Despite ionising radiation, CT is standard for skull fracture assessment. Conventional MRI cannot depict skull structures. 3D-UTE sequences clearly demonstrate skull structures and fractures. UTE plus conventional MRI are superior to CT in craniocerebral trauma assessment. Paediatric and pregnant patients will benefit from this imaging modality.

Multi-slice computed tomography assessment of bronchial compression with absent pulmonary valve.

BACKGROUND: Absent pulmonary valve is a rare cardiovascular anomaly that can result in profound tracheobronchial compression. OBJECTIVE: To demonstrate the advantage of multi-slice CT in diagnosing tracheobronchial compression, its severity as related to the adjacent dilated pulmonary arteries, and associated lung and cardiac lesions. MATERIALS AND METHODS: We included children with absent pulmonary valve who were reviewed by multi-slice CT during a 17-year period. The number and locations of stenoses and lung lesions were noted and the severity of stenosis was categorized. The diameter of the pulmonary artery was measured and associated cardiac defects were demonstrated. RESULTS: Thirty-one children (14 girls and 17 boys) were included. Of these, 29 had ventricular septal defect and 2 had an intact ventricular septum. Twenty-nine children (94%) had tracheobronchial compression, judged to be mild in nine children (31%), moderate in 10 (34%) and severe in 10 (34%). The different locations of the stenosis (carina, main bronchi, lobar and segmental bronchi) were observed. And the number and location of lung lesions demonstrated that the right middle and left upper and lower lobes were often affected. The diameter of the pulmonary artery in these children was well above normal published values, and Spearman rank correlation analysis showed a correlation between the size of the pulmonary artery and the severity of the tracheobronchial stenosis. Nineteen children (61%) underwent surgery and 4 of these children had a multi-slice CT post-operative follow-up study. CONCLUSION: Absent pulmonary valve can cause significant morbidity and mortality in children. Multi-slice CT can accurately depict areas of tracheobronchial compression, associated lung lesions and cardiac defects, helping to direct the surgeon.

Plasma EBV quantification is associated with the efficacy of immune checkpoint blockade and disease monitoring in patients with primary pulmonary lymphoepithelioma-like carcinoma.

Objectives: Primary pulmonary lymphoepithelioma-like carcinoma (PLELC) is a subtype of lung carcinoma associated with the Epstein-Barr virus (EBV). The clinical predictive biomarkers of immune checkpoint blockade (ICB) in PLELC require further investigation. Methods: We prospectively analysed EBV levels in the blood and immune tumor biomarkers of 31 patients with ICB-treated PLELC. Viral EBNA-1 and BamHI-W DNA fragments in the plasma were quantified in parallel using quantitative polymerase chain reaction. Results: Progression-free survival (PFS) was significantly longer in EBNA-1 high or BamHI-W high groups. A longer PFS was also observed in patients with both high plasma EBNA-1 or BamHI-W and PD-L1 ≥ 1%. Intriguingly, the tumor mutational burden was inversely correlated with EBNA-1 and BamHI-W. Plasma EBV load was negatively associated with intratumoral CD8+ immune cell infiltration. Dynamic changes in plasma EBV DNA level were in accordance with the changes in tumor volume. An increase in EBV DNA levels during treatment indicated molecular progression that preceded the imaging progression by several months. Conclusions: Plasma EBV DNA could be a useful and easy-to-use biomarker for predicting the clinical activity of ICB in PLELC and could serve to monitor disease progression earlier than computed tomography imaging.

Vortex formation time as an index of left ventricular filling efficiency: comparison between children volunteers and patients with tetralogy of Fallot.

Background: Vortex formation time (VFT) had been considered a useful marker for assessing diastolic performance. the VFT assessment of diastolic function using four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) has not been used in repair of tetralogy of Fallot (rTOF) patient. The aims of this study were as follows: (I) establish reference ranges for VFT measurements in healthy children and adolescents using 4D flow CMR imaging; and (II) analyze VFT parameters to assess diastole dysfunction in rTOF patients group. Methods: We acquired the CMR data was of 62 healthy participants (aged 6-18 years; male: 40, female: 22) and 20 patients with rTOF (aged 10-13 years; male: 15, female: 5) using 4D flow and cine sequence in routine chamber view. The VFT was calculated based on comparison of different algorithms from cine measurements (VFTvolume) and 4D flow measurements (VFTblood). Then, VFT measurements were compared to subject peak filling rate (PFR), age, and cardiac mass using simple linear regression and multiple regression analyses. Data were also categorized according to age for VFT and cardiac functional assessment comparisons between 3 age groups (Group 1: 6-9 years; Group 2: 10-13 years; Group 3: 14-18 years). The correlation of VFT and cardiac function parameters were analyzed in the rTOF group. Results: Normal mean value of VFTvolume and VFTblood were 4.25±0.92 and 3.77±1.11 in healthy children participants. The VFTvolume was correlated with VFTblood (r=0.61, P<0.001). There was a moderately significant correlation between VFTvolume and PFR (r=0.46, P<0.001) and between VFTblood and PFR (r=0.47, P<0.001), age (r=0.41, P=0.002) and left ventricular (LV) mass (r=0.48, P<0.001). Multiple regression analyses demonstrated that VFTvolume was independently associated with PFR (T=2.239; P<0.05) and VFTblood (T=4.361; P<0.001). There was a significant difference in VFTvolume between healthy controls and rTOF patients (5.44±1.93 vs. 4.27±0.88, P=0.018). Conclusions: The VFT measurements showed that the LV that had appropriate space to form the optimal vortex ring in normal children and adolescents aged 6-18 years old. The VFTvolume could potentially be helpful in improving our understanding of LV diastolic dysfunction in rTOF patients.

Cardiac Computed Tomography-Derived Left Atrial Strain and Volume in Pediatric Patients With Congenital Heart Disease: A Comparative Analysis With Transthoracic Echocardiography.

Purpose: This study aimed at exploring the feasibility and reproducibility of CCT for the measurement of Left Atrial (LA) strain and volume compared with transthoracic echocardiography (TTE) in pediatric patients with congenital heart disease (CHD). Materials and Methods: The present study included 43 postoperative patients with CHD (7.39 ± 3.64 years, 56% male) who underwent clinically indicated CCT, and all patients underwent additional TTE on the same day. LA strain and volume parameters were measured by dedicated software. The correlation and agreement of LA strain and volume parameters were assessed using Pearson's correlation coefficient and Bland-Altman analysis. Intra-class correlation coefficients (ICC) were used to assess CCT intra-observer and inter-observer reproducibility. Results: All strain parameters of CCT were lower compared to TTE (reservoir strain: 28.37 ± 6.92 vs. 32.15 ± 8.15, respectively; conduit strain: 21.33 ± 6.46 vs. 24.23 ± 7.75, respectively; booster strain: 7.04 ± 2.74 vs. 7.92 ± 3.56). While the volume parameters of CCT were higher compared to TTE (LAV: 29.60 ± 19.01 vs. 25.66 ± 17.60, respectively; LAVi: 30.36 ± 22.31 vs. 28.63 ± 19.25, respectively). Both LA strain and volume measurements showed good correlation and agreement between the two modalities (r = 0.63-0.87, p < 0.001). CT-derived LA strain and volume measurements showed good intra- and inter-observer reproducibility using prototype software (ICC = 0.78-0.96). Conclusions: CCT was feasible for measuring LA strain and volume with good correlation and high reproducibility as compared with TTE. As a complementary modality, CCT can regard as an accepted method in the evaluation of LA function in pediatric patients with CHD.

PD-1/PD-L1 combined with LAG3 is associated with clinical activity of immune checkpoint inhibitors in metastatic primary pulmonary lymphoepithelioma-like carcinoma.

Primary pulmonary lymphoepithelioma-like carcinoma (PLELC) is an Epstein-Barr virus (EBV)-related, rare subtype of non-small-cell lung cancer (NSCLC). Immune checkpoint inhibitors (ICI) show durable responses in advanced NSCLC. However, their effects and predictive biomarkers in PLELC remain poorly understood. We retrospectively analyzed the data of 48 metastatic PLELC patients treated with ICI. Pretreated paraffin-embedded specimens (n = 19) were stained for PD-1, PD-L1, LAG3, TIM3, CD3, CD4, CD8, CD68, FOXP3, and cytokeratin (CK) by multiple immunohistochemistry (mIHC). Next-generation sequencing was performed for 33 PLELC samples. Among patients treated with ICI monotherapy (n = 30), the objective response rate (ORR), disease control rate (DCR), median progression-free survival (mPFS), and overall survival (mOS) were 13.3%, 80.0%, 7.7 months, and 24.9 months, respectively. Patients with PD-L1 ≥1% showed a longer PFS (8.4 vs. 2.1 months, p = 0.015) relative to those with PD-L1 <1%. Among patients treated with ICI combination therapy (n = 18), ORR, DCR, mPFS, and mOS were 27.8%, 100.0%, 10.1 months, and 19.7 months, respectively. Patients with PD-L1 ≥1% showed a significantly superior OS than those with PD-L1 <1% (NA versus 11.7 months, p = 0.001). Among the 19 mIHC patients, those with high PD-1/PD-L1 and LAG3 expression showed a longer PFS (19.0 vs. 3.9 months, p = 0.003). ICI also showed promising efficacy for treating metastatic PLELC. PD-L1 may be both predictive of ICI treatment efficacy and prognostic for survival in PLELC. PD-1/PD-L1 combined with LAG3 may serve as a predictor of ICI treatment effectiveness in PLELC. Larger and prospective trials are warranted to validate both ICI activity and predictive biomarkers in PLELC. This study was partly presented as a poster at the IASLC 20th World Conference on Lung Cancer 2019, 7-10 September 2019, Barcelona, Spain.

Postoperative evaluation of left ventricular global strain using cardiac computed tomography in pediatric patients with congenital heart disease: A comparison with echocardiography.

PURPOSE: We explored the feasibility and reproducibility of cardiac computed tomography (CCT)-derived left ventricular (LV) global strain in postoperative childrenwith congenital heart disease (CHD) and compared its correlation and agreement with transthoracic echocardiography (TTE). METHODS: Fifty-one patients (28 males, 23 females) were included who underwent clinically indicated retrospective electrocardiography-triggered CCT. and all patients underwent additional TTE on the same day. LV global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) were measured. Correlations of global strains between CCT and TTE were assessed using Pearson's correlation coefficient. Intra-class correlation coefficients (ICC) were used to assess CCT intra-observer and inter-observer reproducibility. RESULTS: GLS and GCS were not significantly different between CCT and TTE (GLS: -23.54 ± 3.24 vs. -23.85 ± 3.72, respectively, p = 0.415; GCS: -28.21 ± 3.55 vs. -28.79 ± 3.69, respectively, p = 0.155). GRS was significantly different between CCT and TTE (60.79 ± 15.11 vs. 41.73 ± 4.27, respectively, p < 0.001). There was good correlation between CCT- and TTE-derived GLS (r = 0.70, p < 0.001) and GCS (r = 0.68, p < 0.001), but GRS showed no correlation between CCT and TTE (r = 0.09, p = 0.54). CCT-derived global strain showed good intra- and inter-observer reproducibility (ICC = 0.86-0.92), except the inter-observer reproducibility for GRS (ICC = 0.77). CONCLUSIONS: CCT was feasible for postoperative evaluation of LV global strain in pediatric patients with CHD with sufficient reproducibility. CCT-derived global strain can provide additional information in selected CHD patients with poor acoustic windows and who are intolerant to or have contraindications for cardiac magnetic resonance.

Feasibility of using a non-sedation protocol for evaluation of neonatal congenital heart disease by using a 16-cm wide-detector computed tomography with a low radiation dose: preliminary experience from a single pediatric medical center.

The aim of this study is to explore the feasibility of using a non-sedation protocol for the evaluation of neonatal congenital heart disease by using 16-cm wide-detector CT with a low radiation dose. Thirty-four neonates (group 1) were enrolled to undergo cardiac CT without sedation between August 2018 and March 2019. The control group (group 2) comprising 20 inpatient neonates was sedated. Cardiac CT was performed using 16-cm area detector 320-row CT with free breathing and prospective ECG-triggering scan mode. The examination completion time, radiation dose, and image quality were compared between the groups. The results of cardiac CT for patients in group 1 who underwent surgery were compared with surgical findings. Intergroup differences in body weight, age, examination completion time, radiation dose, and image quality evaluation were not significant. There was no significant difference in oxygen saturation before and after the examination in group 1. In all, 98 separate cardiovascular abnormalities in 27 group 1 patients were confirmed using surgical reports. The overall sensitivity, specificity, positive predictive value, and negative predictive value of cardiac CT were 94.90%, 100.0%, 100.0%, and 98.53%. The non-sedation protocol can be applied in neonates with congenital heart disease by using 16-cm wide-detector CT with a low radiation dose. Based on the image quality obtained, non-sedative examination did not extend the examination completion time and helped avoid the possible side effects of sedative drugs.

Pediatric Cardiothoracic CT Guideline Provided by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group: Part 2. Contemporary Clinical Applications.

The use of pediatric cardiothoracic CT for congenital heart disease (CHD) was traditionally limited to the morphologic evaluation of the extracardiac thoracic vessels, lungs, and airways. Currently, the applications of CT have increased, owing to technological advancements in hardware and software as well as several dose-reduction measures. In the previously published part 1 of the guideline by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group, we reviewed the prerequisite technical knowledge for clinical applications in a user-friendly and vendor-specific manner. Herein, we present the second part of our guideline on contemporary clinical applications of pediatric cardiothoracic CT for CHD based on the consensus of experts from the Asian Society of Cardiovascular Imaging CHD Study Group. This guideline describes up-to-date clinical applications effectively in a systematic fashion.

High SHP2 expression determines the efficacy of PD-1/PD-L1 inhibitors in advanced KRAS mutant non-small cell lung cancer.

BACKGROUND: Src homology region 2 domain-containing phosphatase 2 (SHP2) is a novel target for Kirsten rat sarcoma oncogene (KRAS) mutant cancer. We retrospectively studied the significance of SHP2 in KRAS mutant non-small cell lung cancer (NSCLC) treated with immunotherapy and its relationship with tumor microenvironment (TME). METHODS: Sixty-one advanced KRAS mutant NSCLC patients who underwent immunotherapy were enrolled. Next-generation sequencing (NGS) was used to profile mutation status. The expression of SHP2, phospho-SHP2 (pSHP2), and programmed death ligand 1 (PD-L1) were analyzed by immunohistochemistry (IHC). Quantitative multiplexed immunofluorescence cytochemistry (mIFC) analysis was conducted to describe the TME. RESULTS: SHP2 was heterogeneously expressed in 32 samples in both tumor cells and immune cells and highly expressed (H-score >10) in 25 (78.1%) samples. The expression levels of SHP2 and pSHP2 were positively correlated. Stromal SHP2 (s-SHP2) was higher in tumors with PD-L1 ≥50% versus PD-L1 <50% (p = 0.039). By quantitative mIFC analysis, the expression of s-SHP2 had positive correlation with CD8, CD4, CD68, and PD-L1 levels in stromal area. Patients with high SHP2 expression made up 100.0% of the partial respond (PR) and 80.0% of the stable disease (SD), whereas 50.0% of the progress disease (PD). High SHP2 expression was associated with longer progression-free survival (PFS) and overall survival (OS) (p < 0.001, p = 0.013). Patients with high expression of both SHP2 and PD-L1 had longer PFS (p < 0.001). CONCLUSION: High SHP2 expression could predict the efficacy of immunotherapy and better survival in advanced KRAS mutant NSCLC. SHP2 may function in both tumor cells and immune cells, warranting further study on the potential diverse effects of SHP2 inhibition in TME.

CT assessment of tracheobronchial anomaly in left pulmonary artery sling.

BACKGROUND: The left pulmonary artery sling (LPAS) is a rare vascular anomaly where the left pulmonary artery arises from the right pulmonary artery, passes over the right bronchus, and goes posteriorly between the trachea and esophagus. The LPAS is frequently associated with cardiac and non-cardiac defects including tracheobronchial abnormalities. OBJECTIVE: To evaluate the utility of multislice CT (MSCT) and helical CT (HCT) in diagnosing and defining the tracheobronchial anomaly and anatomic relationships between the trachea and aberrant left pulmonary artery. MATERIALS AND METHODS: MSCT or HCT was performed in 27 children to determine the tracheobronchial anatomy and identify tracheobronchial stenosis. Eighteen children underwent surgery. RESULTS: According to the Wells classification of LPAS, which includes two main types and two subtypes, there were eight cases of type 1A, five cases of type 1B, six cases of type 2A and eight cases of type 2B in this group. Twenty-four of the 27 children had substantial tracheobronchial stenosis. Four died before surgery; the 18 had reanastomosis of the left pulmonary artery. Five children also had tracheoplasty; three died after surgery. CONCLUSION: CT, especially MSCT, is an ideal modality for simultaneously identifying aberrant left pulmonary artery and any associated tracheobronchial anomaly. The Wells classification is useful for operative planning.

Systemic ventricular strain and torsion are predictive of elevated serum NT-proBNP in Fontan patients: a magnetic resonance study.

BACKGROUND: This study aimed to investigate the associations between cardiac strain, cardiac torsion, ventricular volumes, and ventricular ejection fraction, with N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels in Fontan patients who were age- and gender-matched with healthy control subjects. METHODS: Cardiovascular magnetic resonance (CMR) studies performed in 22 (15 male, 7 female) patients with single-ventricle physiology (all morphological left ventricles) palliated with Fontan and 17 (10 male, 7 female) age- and gender-matched healthy children volunteers were retrospectively analyzed. Serum NT-proBNP levels were obtained in Fontan subjects. Standard post-processing of CMR images included systemic ventricular end-diastolic and end-systolic volumes, stroke volume, cardiac mass, atrioventricular regurgitation, and ejection fraction. CMR tissue tracking (TT) software was used to quantify global longitudinal strain (GLS), global radial strain (GRS), and global circumferential strain (GCS) and torsion of the systemic ventricle. Pearson and Spearman correlation coefficients were used in comparisons of correlations between NT-proBNP and functional parameters in repair Fontan patients. Intra-observer and inter-observer variability of CMR strain and torsion values were determined from 10 randomly selected Fontan subjects and 10 randomly selected control subjects. RESULTS: GLS was significantly lower in Fontan patients than in control subjects (-15.19±2.94 vs. -19.97±1.70; P<0.001). GLS was not significantly different between normal NT-proBNP levels and high NT-proBNP levels in Fontan patients (-15.59±2.72 vs. -14.62±3.32; P=0.462). The GCS of repair Fontan patients was not significantly lower than that of the control group (-16.76±3.27 vs. -17.88±2.26; P=0.235). GCS was significantly different between normal and high NT-proBNP levels group in Fontan patients (-17.95±2.43 vs. -15.04±3.67; P=0.036). The peak systolic torsion and peak systolic torsion rates were significantly lower in Fontan patients than in control subjects (0.81±0.41 vs. 1.07±0.36, P=0.044; 7.36±3.41 vs. 9.85±2.61, P=0.017). Peak systolic torsion was significantly lower in Fontan patients with normal NT-proBNP levels than in high NT-proBNP subjects (0.67±0.43 vs. 1.01±0.29; P=0.036). GCS and torsion were more strongly correlated with NT-proBNP in the patient group (r=0.541 for GCS; r=0.588 for torsion, P<0.01). The parameters of strain and torsion could be reproduced with sufficient accuracy by intra-observer agreement(biases =0.04 for GLS; biases =0.66 for GCS; biases =1.03 for GRS; biases =0.04 for torsion) and inter-observer agreement (biases =0.32 for GLS; biases =0.85 for GCS; biases =1.52 for GRS; biases =0.18 for torsion). CONCLUSIONS: GLS is an earlier marker of contractile dysfunction in repair Fontan patients. Peak systolic torsion may be a biomarker for determining subclinical dysfunction, as it is more strongly correlated with serum biomarkers of ventricular function than ventricular size or ejection fraction.

Prenatal and Postnatal Diagnosis of Rhabdomyomas and Tuberous Sclerosis Complex by Ultrafast and Standard MRI.

OBJECTIVE: To examine the features of cardiac rhabdomyomas and tuberous sclerosis in fetuses and infants using magnetic resonance imaging (MRI) and to determine whether MRI is an effective tool to facilitate early detection of tuberous sclerosis complex (TSC). METHODS: Fifteen patients with TSC were evaluated by ultrafast or standard MRI between June 2005 and September 2016. Fifteen patients were divided into two groups. Group A included five cases in utero and followed in infancy with gestational ages from 26 + 1 to 38 + 2 wk. Group B included ten cases aged from 36 d to 18-mo-old. RESULTS: There were 11 and 10 cardiac lesions of prenatal and postnatal period respectively in five subjects of Group A and 27 cardiac lesions in ten subjects of Group B. There were more than 31 prenatal brain lesions and 30 postnatal brain lesions in Group A and 169 lesions in Group B. Standard postnatal brain MRI confirmed the prenatal study of Group A. At 1 y follow up of Group A, there was partial regression of 2 cardiac lesions, complete regression of 1 cardiac lesion, no obvious regression of 8 cardiac lesions. CONCLUSIONS: When one or multiple cardiac tumors are detected by ultrasound in fetal period or some specific clinical manifestations are presented in infancy, fetal ultrafast MRI or standard MRI is suggested to make early diagnosis of TSC.

A prospective evaluation of contrast and radiation dose and image quality in cardiac CT in children with complex congenital heart disease using low-concentration iodinated contrast agent and low tube voltage and current.

OBJECTIVE: To the assess image quality, contrast dose and radiation dose in cardiac CT in children with congenital heart disease (CHD) using low-concentration iodinated contrast agent and low tube voltage and current in comparison with standard dose protocol. METHODS: 110 patients with CHD were randomized to 1 of the 2 scan protocols: Group A (n = 45) with 120 mA tube current and contrast agent of 270 mgI/ml in concentration (Visipaque™; GE Healthcare Ireland, Co., Cork, UK); and Group B (n = 65) with the conventional 160 mA and 370 mgI/ml concentration contrast (Iopamiro®; Shanghai Bracco Sine Pharmaceutical Corp Ltd, Shanghai, China). Both groups used 80 kVp tube voltage and were reconstructed with 70% adaptive statistical iterative reconstruction algorithm. The CT value and noise in aortic arch were measured and the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. A five-point scale was used to subjectively evaluate image quality. Contrast and radiation dose were recorded. RESULTS: There was no difference in age and weight between the two groups (all p > 0.05). The iodine load and radiation dose in Group A were statistically lower (3976 ± 747 mgI vs 5763 ± 1018 mgI in iodine load and 0.60 ± 0.08 mSv vs 0.77 ± 0.10 mSv in effective dose; p < 0.001). However, image noise, CT value, CNR, SNR and subjective image quality for the two groups were similar (all p > 0.05), and with good agreement between the two observers. Comparing the surgery results, the diagnostic accuracy for extracardiac and intracardiac defects for Group A was 96% and 92%, respectively, while the corresponding numbers for Group B were 95% and 93%. CONCLUSION: Compared with the standard dose protocol, the use of low tube voltage (80 kVp), low tube current (120 mA) and low-concentration iodinated contrast agent (270 mgI/ml) enables a reduction of 30% in iodine load and 22% in radiation dose while maintaining compatible image quality and diagnostic accuracy. Advances in knowledge: The new cardiac CT scanning protocol can largely reduce the adverse effects of radiation and contrast media to children. Meanwhile, it also can be used effectively to examine complex CHD.