Xiaojuan Guo

Capital Medical University, Peping, Beijing, China

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Publications (13)20.51 Total impact

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    ABSTRACT: We aimed to determine the correlation between flow characteristics of the proximal pulmonary arteries and vena cava obtained by 3.0 T phase-contrast magnetic resonance imaging (MRI) and hemodynamic characteristics by right heart catheterization in patients with chronic thromboembolic pulmonary hypertension.
    Diagnostic and interventional radiology (Ankara, Turkey) 09/2014; 20(5):414-20. · 1.03 Impact Factor
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    ABSTRACT: The aim of the present study was to retrospectively evaluate the incidence and morphological features of coronary artery fistulas (CAFs) detected by dual-source computed tomography coronary angiography (DS-CTCA). Between January 2011 and January 2013, 19,584 consecutive patients that had undergone electrocardiogram-triggering DS-CTCA were retrospectively reviewed. Image reconstructions were performed and image quality was evaluated. The medical information of the patients with CAF was reviewed from the medical records. Among the 19,584 patients, 66 patients were diagnosed with CAFs by CTCA, including 60 patients with coronary pulmonary artery fistulas (CPAFs) and six with coronary left ventricular fistulas. Therefore, the incidence of CAFs was 0.34%. Image quality was considered to be excellent in 61 patients and moderate in five cases. CPAFs were identified as small and tortuous vessels in 24 patients and dilated vessels close to the surface of the pulmonary artery (PA) in 36 patients. The coronary left ventricular fistulas were identified as dilated vessels that were draining into the posterior wall of the left ventricle. Among the 66 patients, 54 patients had one traceable fistula and the remaining 12 patients were shown to have two fistula vessels. The average diameter of the detected fistulas, measured with CTCA, was 3.1±1.9 mm. A high-density flow jet of contrast agent shunting from the fistula into the low density PA was observed in 46 patients with CPAF. The results indicate that DS-CTCA is a reliable noninvasive tool that allows the accurate delineation of CAFs.
    Experimental and therapeutic medicine 05/2014; 7(5):1155-1159. · 0.34 Impact Factor
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    ABSTRACT: The septal angle, an angle between the interventricular septum and the line connecting the sternum midpoint and thoracic vertebral spinous process, as measured by computed tomographic pulmonary angiography (CTPA), has been observed to be increased in patients with pulmonary hypertension (PH), but its meaning remains unclear. The aim of this study was to investigate the potential role of the septal angle in evaluating hemodynamics and its association with N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients with PH. Patients with PH (n=106), including 76 with chronic thromboembolic pulmonary hypertension (CTEPH) and 30 with pulmonary artery hypertension (PAH), were retrospectively reviewed. The patients underwent CTPA prior to right-heart catheterization. The septal angle was measured on transversal CTPA images. Hemodynamic parameters were evaluated by right-heart catheterization. The level of plasma NT-proBNP was measured by enzyme-linked sandwich immunoassay. The septal angle had a moderate correlation with cardiac output (CO; r=-0.535, P=0.000) and a high correlation with pulmonary vascular resistance (PVR; r=0.642, P=0.000). The mean level of NT-proBNP in PH was 1,716.09±1,498.30 pg/ml, which correlated with the septal angle (r=0.693, P=0.000). In a stepwise forward regression analysis, the Septal angle was entered into the final equation for predicting PVR, leading to the following equation: PVR = 28.256 × Septal angle - 728.72. In CTEPH, the Septal angle strongly correlated with NT-proBNP (r=0.668, P=0.000) and PVR (r=0.676, P=0.000). In PAH, the Septal angle strongly correlated with NT-proBNP (r=0.616, P=0.003) and PVR (r=0.623, P=0.000). The CTPA-derived Septal angle is a superior predictor for evaluating and monitoring the level of NT-proBNP and PVR in patients with PH.
    Experimental and therapeutic medicine 12/2013; 6(6):1350-1358. · 0.34 Impact Factor
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    ABSTRACT: To explore the reliability and feasibility of blood oxygenation level-dependent-based functional magnetic resonance imaging (BOLD-fMRI) to depict hypoxia in breast invasive ductal carcinoma. A total of 103 women with 104 invasive ductal carcinomas (IDCs) underwent breast BOLD-fMRI at 3.0 T. Histological specimens were analysed for tumour size, grade, axillary lymph nodes and expression of oestrogen receptors, progesterone receptors, human epidermal growth factor receptor 2, p53, Ki-67 and hypoxia inducible factor 1α (HIF-1α). The distribution and reliability of R2* were analysed. Correlations of the R2* value with the prognostic factors and HIF-1α were respectively analysed. The R2* map of IDC demonstrated a relatively heterogeneous signal. The mean R2* value was (53.4 ± 18.2) Hz. The Shapiro-Wilk test (W = 0.971, P = 0.020) suggested that the sample did not follow a normal distribution. The inter-rater and intrarater correlation coefficient was 0.967 and 0.959, respectively. The R2* values of IDCs were significantly lower in patients without axillary lymph nodes metastasis. The R2* value had a weak correlation with Ki67 expression (r = 0.208, P = 0.038). The mean R2* value correlated moderately with the level of HIF-1α (r = 0.516, P = 0.000). BOLD-fMRI is a simple and non-invasive technique that yields hypoxia information on breast invasive ductal carcinomas. • Blood oxygenation level-dependent-based MRI can be used to assess tumour hypoxia. • BOLD-fMRI shows characteristic features of breast invasive ductal carcinoma. • R2* values of BOLD-fMRI correlate with hypoxia inducible factor 1α.
    European Radiology 07/2013; · 4.34 Impact Factor
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    ABSTRACT: Background The diagnostic accuracy of cardiovascular magnetic resonance (CMR) for pulmonary hypertension (PH) compared with right heart catheterization (RHC) were assessed. The purpose of this systematic review is to comprehensively evaluate the diagnostic accuracy of CMR evaluating PH. Methods Published literature was obtained by PUBMED; Web of Knowledge; Cochrane library; Embase; Biosis Preview; CNKI and Chongqing VIP databases and all studies were inclusive until December 2012. Studies relevant to pulmonary hypertension and it’s imaging in cardiovascular magnetic resonance and right heart catheterization were included if correlation coefficient was elucidated clearly. QUADAS-2 score assessed the quality of studies. Sensitivity and specificity were pooled separately and compared with overall accuracy measures: diagnostic odds ratio and symmetric summary receiver operating characteristic. Results Sixteen studies were included in the systematic review. Of all the studies, the most widely used index was ventricular mass index (VMI) of CMR. We performed meta-analysis for VMI among 429 patients in 5 individual studies which showed a modest diagnostic accuracy of VMI for pulmonary hypertension with a summary sensitivity and specificity of 84% (95% CI: 79% to 87%) and 82% (95% CI: 73% to 89%) respectively. In addition, the summary positive likelihood ratio was 4.894, indicating that VMI of CMR has a modest ability to distinguish PH patients from healthy subjects with a cut-off point of 0.45 by functional and structural measures. Conclusions This systematic review and meta-analysis indicates that VMI seems to have a moderate sensitivity and specificity for detection of PH. The application values of other parameters still need further investigation.
    The Canadian journal of cardiology 01/2013; · 3.12 Impact Factor
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    ABSTRACT: Leukoaraiosis (LA) is a common radiological finding in the elderly and may reflect cerebral small vessel disease (SVD). Although SVD has been identified as a major cause of vascular cognitive impairment or vascular dementia, the mechanisms for this association remain unclear. We therefore aimed to measure brain metabolites in LA using proton magnetic resonance spectroscopy ((1)H-MRS) as to determine the relationship between cognitive function and neurochemical white matter profile. We recruited 23 patients with LA and 23 age- and sex-matched healthy controls consecutively. Multi-voxel (1)H-MRS was performed with a volume of interest located in centrum semiovale that contained mainly white matter voxels. Three main ratios of N-acetyl aspartate (NAA)/Cr, choline (Cho)/Cr and NAA/Cho were obtained. Spearman rank correlation coefficients were calculated between the cognitive function and the measured metabolite ratios. We found significantly lower levels of NAA/Cho and NAA/Cr ratios in lesioned white matter in patients with LA than healthy controls (P<0·05). The ratios of NAA/Cho and NAA/Cr in normal appearing white matter (NAWM) were higher than lesioned white matter and lower than controls, but this difference was not significant (P>0·05). There was a positive relationship between Mini-Mental State Examination (MMSE) and NAA/Cho in NAWM (r = 0·417, P = 0·048), and also a positive relationship between MMSE and NAA/Cr in lesioned white matter (r = 0·551, P = 0·006) in patients with LA. A positive relationship between the Z scores of the executive function and NAA/Cho in lesioned white matter (r = 0·557, P = 0·006) was also found. The main finding of this study was a significant reduction in the ratios of NAA/Cr and NAA/Cho in lesioned white matter, which indicates a marker of neuronal loss or dysfunction in patients with LA, which was correlated with cognitive function. This relationship between cognitive function and metabolic changes suggests that (1)H-MRS can be explored as a marker for cognitive dysfunction in patients with LA.
    Neurological Research 12/2012; 34(10):989-97. · 1.18 Impact Factor
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    ABSTRACT: The assessment of myocardial viability has become an important aspect of the diagnostic and prognostic work-up of patients with coronary artery disease. Technetium-99m labelled sestamibi ((99m)Tc-MIBI) myocardial perfusion imaging may underestimate the viability of ischaemic myocardium. Technetium-99m labelled 4,9-diaza-3,3,10,10-tetramethyldodecan-2,11-dione dioxime ((99m)Tc-HL91) is a hypoxia-avid agent which can identify acutely ischaemic viable myocardium in a canine model using a standard gamma camera. The aim of this study was to evaluate uptake character of ischaemic viable myocardium and diagnostic performance of single-photon emission computed tomography (SPECT) imaging by (99m)Tc-HL91 and (99m)Tc-MIBI in detecting ischaemic viable myocardium in coronary heart disease. A total of 41 patients with coronary artery disease were recruited from March 2008 to May 2009. For detecting ischaemic viable myocardium, SPECT imaging by (99m)Tc-HL91 and (99m)Tc-MIBI were performed in all patients before coronary revascularization. Six patients with single ischaemic myocardial segment received a 2-day SEPCT/CT imaging protocol and the uptake of (99m)Tc-HL91 in ischaemic myocardium was quantitatively analysed. The remaining 35 patients received a 1-day (99m)Tc-HL91 and (99m)Tc-MIBI SPECT imaging protocol. Resting (99m)Tc-MIBI myocardial perfusion imaging in 3-18 months after revascularization was used as the standard methodology to evaluate the myocardial viability. In 41 patients, 66 ischaemic myocardial segments were proven to be viable and 12 to be necrotic by resting (99m)Tc-MIBI myocardial perfusion imaging after coronary revascularization. Furthermore, 60 viable segments with negative uptake of (99m)Tc-MIBI showed positive uptake of (99m)Tc-HL91. The remaining six viable segments and 12 necrotic segments showed both negative uptake of (99m)Tc-HL91 and (99m)Tc-MIBI. The sensitivity, specificity, accuracy, Younden Index, positive predictive value and negative predictive value for evaluating ischaemic viable myocardium were 90·9%, 100%, 92·3%, 90·9%, 100% and 66·7%, respectively. Ischaemic viable myocardium had the negative (99m)Tc-MIBI uptake and positive (99m)Tc-HL91 uptake, which demonstrated a mismatched uptake character. Quantitative analysis indicated the uptake of (99m)Tc-HL91 in viable myocardium was increasing in the first 1-3 h and remained stable at the 3-4 h after injection. Functional SPECT imaging with (99m)Tc-HL91 and (99m)Tc-MIBI can be used to detect the seriously ischaemic but viable myocardium with a mismatched uptake character. The uptake of (99m)Tc-HL91 in the viable myocardium reached a stable level at 3-4 h after injection.
    Clinical Physiology and Functional Imaging 01/2012; 32(1):25-32. · 1.33 Impact Factor
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    ABSTRACT: OBJECTIVES: The purpose is to identify the role of cardiovascular parameters of computed tomographic pulmonary angiography (CTPA) to assess pulmonary vascular resistance (PVR) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). BACKGROUND: The assessment of PVR is of great importance in the management of patients with CTEPH. The role of CPTA in assessment of PVR of CTEPH remains to be explored. METHODS: Clinical and radiological data of 90 patients (55 men, age 17-84years) with CTEPH were retrospectively reviewed in this study. All patients received CTPA before right-heart catheterization. Cardiovascular parameters and Pulmonary Artery Obstruction Indices including Qanadli Index and Mastora Index were evaluated on CTPA. Hemodynamic PVR was calculated with the standard formula according to data from right-heart catheterization. The correlation of cardiovascular parameters of CTPA and PVR was analyzed. RESULTS: In Cardiovascular parameters, neither Qanadli Index(r=0.134, p=0.208) nor Mastora Index (r=0.149, p=0.90) did correlate with PVR. Cobb angle(r=0.613, p=0.000), the ratio of right to left ventricular area(r=0.422, p=0.000)and the ratio of right to left ventricular transverse diameter (r=0.410, p=0.000) respectively correlated with PVR. By receiver operating characteristic curve analysis, a Cobb angle cutoff value of 67.55° had a sensitivity of 72.5% and a specificity of 84.0% to determine PVR ≥1000 (dyn.sec/cm(5)) and its Area Under Curve is (0.800±0.048). By stepwise linear regression analysis, Cobb angle was only one variable (R=0.601) shown to be independently associated with PVR, leading to the following equation: PVR=25.796×Cobb angle-585.935(F=37.929, p=0.000). CONCLUSION: The analysis of CTPA-derived cardiovascular parameters, especially the Cobb angle, is a reliable tool for estimating PVR in patients with CTEPH, but Pulmonary Artery Obstruction Indices do not correlate with PVR.
    International journal of cardiology 08/2011; · 6.18 Impact Factor
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    ABSTRACT: The aim was to investigate the role of computed tomographic pulmonary angiography (CTPA) in the assessment of severity and right ventricular function in chronic thromboembolic pulmonary hypertension (CTEPH). Clinical and radiological data of 56 patients with CTEPH January 2006-October 2009 were retrospectively reviewed in the present study. All patients received CTPA with a 64-row CT using the retrospective ECG-Gated mode before digital subtraction pulmonary angiography and right-heart catheterization. CTPA findings including Right Ventricular diameter (RVd) and left ventricular diameter (LVd) were measured at the end diastole. CT Pulmonary Artery Obstruction Indexes including Qanadli Index and Mastora Index were used in the assessment of severity of pulmonary arterial obstruction. Hemodynamic parameters and pulmonary hypertension classification were evaluated by right-heart catheterization in all patients. Right ventricular function was measured with echocardiography in 49 patients. Qanadli Index and Mastora Index respectively were (37.93±14.74)% and (30.92±16.91)%, which showed a significant difference (Z=-5.983, P=0.000) and a good correlation (r=0.881, P=0.000). Neither Qanadli nor Mastora Index correlated with pulmonary hypertension classification (r=-0.009, P=0.920) or New York Heart Association heart function classification (r=-0.031, P=0.756). Neither Qanadli nor Mastora Index correlated with any echocardiographic right ventricular parameters (P>0.05), while RVd/LVd by CTPA correlated with echocardiographic right ventricular functional parameters (P<0.05). Both Qanadli (r=-0.288, P=0.006) and Mastora Index (r=-0.203, P=0.032) demonstrated a weakly negative correlation with SPO2. CTPA findings correlated with hemodynamic variables. Backward linear regression analysis revealed that the RVd/LVd, Right Ventricular Anterior Wall Thickness (RVAWT), Main Pulmonary Artery trunk diameter (MPAd) were shown to be independently associated with mean Pulmonary Artery Pressure (mPAP) levels (model: r2=0.351, P=0.025; RVd/LVd: beta=11.812, P=0.000; RVAWT: beta=2.426, P=0.000; MPAd: beta=0.677, P=0.003). Computed tomographic pulmonary angiography is a valuable tool to evaluate hemodynamics, right ventricular function of CTEPH, but neither Qanadli Index nor Mastora Index can reflect pulmonary arterial obstruction in CTEPH accurately.
    European journal of radiology 10/2010; 80(3):e462-9. · 2.65 Impact Factor
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    ABSTRACT: Objective To evaluate Wells, Kahn, St. André and Constans scores for the prediction of deep venous thrombosis in Chinese patients.Methods One hundred and seventy-two patients, prospectively, blinded referred for evaluation with four clinical-score systems for suspected deep venous thrombosis, were examined by ultrasonography. Sensitivity, specificity, positive predictive value, negative predictive value and receiver operation curves were calculated for four clinical scores. The difference between areas of the ROC curve for each of the scores was compared with others and reference line.ResultsForty-six of 172 patients had deep venous thrombosis proven by sonography. The sensitivity, specificity, positive predictive value and negative predictive value for Wells score was 91.3%, 57.1%, 43.8% and 94.7%, respectively, for Kahn score; 65.2%, 71.4%, 45.5% and 84.9%, respectively, for St. André score; 63%, 38.9%, 27.4% and 74.2% respectively, for Constans score; 95.7%, 34.9%, 34.9% and 95.7% respectively. Area under ROV curve of Constans score was 0.814, which was similar to that of Wells score, then followed by Kahn score and that of St. André score was no difference with the reference line.Conclusion Based on the results of our study, the sensitivity, negative prediction value and area under ROC curve are larger for Constans score and Wells score in Chinese hospitalized patients than that of Kahn score or St. André score. Considering the aim of the clinical assessment, Constans score and Wells score are more efficient for Chinese hospitalized patients.
    Journal of Nanjing Medical University 07/2008; 22(4):230–233.
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    ABSTRACT: Objective To analyze the value of CTPA in assessing the dissolve of embolus and the function of the right ventricle dynamically.
    Journal of Nanjing Medical University 01/2008; 22(3):188-192.
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    ABSTRACT: Objective To analyze the value of CT pulmonary angiography (CTPA) in assessing right ventricular dysfunction (RVD) after acute pulmonary embolism.
    Journal of Nanjing Medical University 01/2008; 22(4):234-237.
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    ABSTRACT: ObjectiveTo analyze the value of CTPA in assessing the dissolve of embolus and the function of the right ventricle dynamically.MethodsTwenty-three cases of massive pulmonary embolism were analyzed retrospectively. The pulmonary artery obstruction index and the right ventricular function parameters were collected and analyzed on CTPA before thrombolytic therapy, 24 hours and 14 days after therapy, respectively.ResultsThe pulmonary artery obstruction index decreased gradually, and there was significant difference before therapy, 24 hours and 2 weeks after therapy. Twenty-four hours after therapy, the maximal short axes diameter and the maximal transverse area of right ventricle(RVd, RVs) decreased significantly, the maximal short axes diameter and the maximal transverse area of left ventricle(LVd, LVs) increased significantly, and the RVd/LVd, RVs/LVs decreased apparently. The pulmonary artery symbolic pressure before and 24 hours after therapy were apparently different. There was no significant difference between azygos vein, the super vena cava, the main pulmonary artery and vein reflux before and after therapy.ConclusionCTPA can evaluate the pulmonary artery obstruction degree and right ventricular function dynamically.
    Journal of Nanjing Medical University.