Reference values for quantitative left ventricular and left atrial measurements in cardiac computed tomography

To assess reference values for left ventricular (LV) and left atrial (LA) dimensions, global LV function, and LV-myocardial mass for cardiac CT. We examined 120 subjects undergoing a coronary angiography using 64-slice and dual-source CT. All individuals had a low cardiovascular risk, normal ECG, negative biomarkers, and a normal cardiac CT examination. All subjects had a negative medical history of cardiovascular disease both on admission and at clinical 6-month follow-up. The following measurements were obtained: septal wall thickness (SWT), posterior wall thickness (PWT), LV inner diameter (LVID), LA anterior posterior diameter (LAD(sys)), end-systolic volume (ESV), and end-diastolic volume (EDV), LV-myocardial mass (LVMM). We found significant gender-related differences for all LV dimensions (SWT(sys), SWT(dia),PWT(sys),PWT(dia),LVID(sys),LVID(dia)). LAD(sys) showed no significant difference between males and females. Significant differences were found for global LV functional parameters including ESV, EDV, and SV, whereas no significant differences were found for the EF. LV-myocardial mass parameters showed significant gender-related differences. No significant correlation was found between any of these parameters and age. All data were transferred to percentile ranks. This study provides gender-related reference values and percentiles for LV and LA quantitative measurements for cardiac CT and should assist in interpreting results.     

Assessment of left ventricular deformation in patients with Ebstein’s anomaly by cardiac magnetic resonance tissue tracking

PurposeThe aim of this study was to clarify the feasibility of myocardial strain using cardiovascular magnetic resonance (CMR) for the evaluation of left ventricular (LV) deformation in patients with Ebstein’s anomaly (EA).Materials and methodsWe recruited 32 patients with EA and 30 controls for CMR examination and measured LV function, dimension and tissue tracking parameters (the global and regional radial, circumferential and longitudinal peak strain), together with the right ventricle (RV) dimension. LV strain parameters were compared among the controls, patients with preserved LV ejection fraction (LVEF; ≥55%), and patients with reduced LVEF (<55%). Pearson’s correlation was used to evaluate relationships between tissue tracking parameters with the RVEDD/LVEDD index and LVEF. An ROC analysis was also performed to determine whether the cut-off values for PS could be used to differentiate LV dysfunction between patients with EA and controls. The intraclass correlation coefficient (ICC) was used to assess the inter- and intra-observer variability.ResultsThe global strain parameters all decreased significantly in the EA group compared with the control group (all P < 0.05). Furthermore, the global radial and circumferential peak strain (PS) were obviously even lower in the reduced LVEF group than the strain measured in preserved LVEF groups (28.64% vs. 37.39%, p < 0.05; and −8.20% vs. −17.89%; p < 0.05; respectively). The regional strain abnormalities in EA patients were mainly involved in basal and middle segments. The results also demonstrated a significant correlation between the ratio of the RV end-diastolic dimension to the LV end-diastolic dimension (RVEDD/LVEDD index) with the global circumferential PS (r = 0.508) and the longitudinal PS (r = 0.474), as well as a good correlation between radial PS and LVEF (r = 0.465). The ICCs for intra- and inter-observer variability were 0.797–0.904 and 0.701–0.896.ConclusionsLV strain serves an earlier and more comprehensive measurement of LV dysfunction than LVEF in EA, which could potentially be included as a supplementary diagnostic procedure in the evaluation of EA.     

Exercise blood pressure and cardiac structure: A systematic review and meta-analysis of cross-sectional studies

ObjectivesA hypertensive response to exercise (HRE) is associated with cardiovascular disease and high blood pressure (BP). Sub-clinical changes to cardiac structure may underlie these associations, although this has not been systematically determined. Via systematic review and meta-analysis, we aimed to (1) assess the relationship between exercise BP and cardiac structure, and (2) determine if cardiac structure is altered in those with an HRE, across various study populations (including those with/without high BP at rest).Design and methodsThree online databases were searched for cross-sectional studies reporting exercise BP, HRE and cardiac structural variables. Random-effects meta-analyses and meta-regressions were used to calculate pooled correlations between exercise BP and cardiac structure, and pooled mean differences and relative risk between those with/without an HRE.ResultsForty-nine studies, (n = 23,707 total; aged 44 ± 4 years; 63% male) were included. Exercise systolic BP was associated with increased left ventricular (LV) mass, LV mass index, relative wall thickness, posterior wall thickness and interventricular septal thickness (p < 0.05 all). Those with an HRE had higher risk of LV hypertrophy (relative risk: 2.6 [1.85–3.70]), increased LV mass (47 ± 7 g), LV mass index (7 ± 2 g/m²), relative wall thickness (0.02 ± 0.005), posterior wall thickness (0.78 ± 0.20 mm), interventricular septal thickness (0.78 ± 0.17 mm) and left atrial diameter (2 ± 0.52 mm) vs. those without an HRE (p < 0.05 all). Results were broadly similar between studies with different population characteristics.ConclusionsExercise systolic BP is associated with cardiac structure, and those with an HRE show evidence towards adverse remodelling. Results were similar across different study populations, highlighting the hypertension-related cardiovascular risk associated with an HRE.     

Cardiac MRI left ventricular global function index and quantitative late gadolinium enhancement in unrecognized myocardial infarction

PurposeTo compare left ventricular global function index (LVGFI) and quantitative late gadolinium enhancement (LGE) in patients with unrecognized myocardial infarction (UMI), recognized myocardial infarction (RMI) and without myocardial infarction (MI).Material and methodsUnder waiver of the Institutional Review Board 235 patients (age 63.5 ± 10.5 years, 57 female) were retrospectively evaluated. All patients had undergone cardiac MRI at 1.5T for symptoms of CAD. 67 patients (29%) had suffered a known RMI before. Functional imaging and full-intensity late gadolinium enhancement (LGE) imaging were evaluated for LVGFI and quantitative LGE mass.ResultsOf 168 patients without history of RMI, 48 patients (29%) had UMI, 120 patients had no MI. LVGFI was lower in RMI patients (34 ± 8% [range 16;52]), and UMI patients (35 ± 8% [range 10;51]), compared to patients with no MI (38 ± 7% [range 16;55]) respectively and similar between RMI and UMI patients. RMI patients had full-intensity LGE in 11 ± 6% of left ventricular myocardial mass (LVMM). UMI patients had LGE in 9 ± 5% of LVMM. RMI patients had significantly more LGE than UMI patients (p = 0.0096).ConclusionLGE quantification is effective to assess infarction scar size in RMI and UMI patients. LVGFI provides information on cardiac function and morphology but does not allow for a reliable differentiation between patients with and without history of MI, due small differences and wide overlap of LVGFI values for all three patient groups. This may be a reason why LVGFI is not applied in clinical routine.     

Can left ventricular function be assessed on non-ECG-gated CT?

To evaluate whether non-gated computed tomography (CT) can assess left ventricular (LV) function, 101 patients with both CT and echocardiography were selected, with ejection fraction < 50% on echocardiography used as a reference standard. CTs were blindly reevaluated, and qualitative assessment of LV dysfunction on CT correlated with echocardiographic dysfunction, odds ratio of 21.0 (95% confidence interval=6.55–71.0), specificity of 86% (56/65). Systolic and diastolic images were identified on CT, and the ratio of systolic to diastolic LV internal diameters and ratio of LV to RV internal diameter were determined, both showing correlation with LV dysfunction on echocardiography (P< .0001). Non-gated CT can be used to predict LV dysfunction.     

Validity of predicting left ventricular end systolic pressure changes following an acute bout of exercise

ObjectivesLeft ventricular end systolic pressure (LV ESP) is important in assessing left ventricular performance and is usually derived from prediction equations. It is unknown whether these equations are accurate at rest or following exercise in a young, healthy population.DesignMeasured LV ESP vs. LV ESP values from the prediction equations were compared at rest, 15 min and 30 min following peak aerobic exercise in 60 participants.MethodsLV ESP was obtained by applanation tonometry at rest, 15 min post and 30 min post peak cycle exercise.ResultsMeasured LV ESP was significantly lower (p < 0.05) at all time points in comparison to the two calculated values. Measured LV ESP decreased significantly from rest at both the post15 and post30 time points (p < 0.05) and changed differently in comparison to the calculated values (significant interaction; p < 0.05). The two LV ESP equations were also significantly different from each other (p < 0.05) and changed differently over time (significant interaction; p < 0.05).ConclusionsThe two commonly used prediction equations did not accurately predict either resting or post exercise LV ESP in a young, healthy population. Thus, LV ESP needs to be individually determined in young, healthy participants. Non-invasive measurement through applanation tonometry appears to allow for a more accurate determination of LV ESP.     

Value of multislice CT coronary arteries calcification scoring in the prediction of coronary arteries pathology in chronic kidney disease patients

PurposeTo determine the value of multislice CT coronary artery calcification (CAC) scoring in the prediction of future cardiac events in known chronic kidney disease (CKD) patients using conventional coronary angiography as the standard reference.Patients and methodsFifty-eight patients with CKD on hemodialysis underwent CT CAC scoring using multislice scanner and conventional coronary angiography. Results of CAC scoring were compared to the findings of conventional coronary angiography.ResultsMean CAC scoring in patients with significant coronary arteries stenotic lesions was higher than in patients with no significant coronary arteries stenotic lesions with significant difference (P < 0.001).Mean patient CAC scoring was strongly correlated with the number of coronary arteries with significant stenotic lesions (r = 0.910).ConclusionCT CAC scoring is a non-invasive technique which can be used in the evaluation and follow up of CKD patients’ coronary arteries without the use of contrast medium reducing the number of invasive coronary angiography needed.     

Left ventricular and atrial strain imaging with cardiac computed tomography: Validation against echocardiography

BackgroundData on left ventricular (LV) deformation imaging using CT angiography (CTA) are scarce and the feasibility of atrial deformation analysis by CT has not been addressed. We aimed to compare 2D echocardiographic and CT derived LV and left atrial (LA) global longitudinal strain (GLS) obtained by using a novel feature tracking algorithm in patients following transcatheter aortic valve implantation.MethodsTwenty-eight patients were included who underwent retrospectively-gated 256-slice CTA and speckle-tracking echocardiography (STE) on the same day. CT datasets in 10% increments were reconstructed throughout the cardiac cycle. LV GLS and LA global peak reservoir strain (LA GS) was measured.ResultsMedian absolute values for LV GLS were 19.9 [14.8–22.4] vs. 19.9 [16.8–24.7], as measured by CT vs STE, respectively (p = 0.017). We found good inter-modality correlation for LV GLS (ρ = 0.78, p < 0.05) with a mean bias of −1.6. Regarding atrial measurements, the median LA GS was 19.0 [13.5–27.3] for CT vs. 28.0 [17.5–32.6] for STE (p < 0.001) with a mean bias of −5.6 between CT and STE and a correlation coefficient of ρ = 0.87, p < 0.001. CT measurements were highly reproducible: intra-observer intra-class correlation coefficient was 0.96 for LV GLS and 0.95 for LA GS.ConclusionWe detected good correlation between CTA and echocardiography-based LV and LA longitudinal strain parameters. CTA provides accurate strain measurements with high reproducibility. Feature tracking-based deformation analysis could provide a clinically important addition to CT examinations by complementing anatomical information with functional data.     

Impact on mortality of coronary and non-coronary cardiovascular findings in non-gated thoracic CT by malignancy status

PurposeThe prognostic value of coronary artery calcification (CAC) assessed on non-gated thoracic CT scans has only been explored in population-based studies. We explored the impact of the presence and extension of CAC, as well as of non-coronary atherosclerosis cardiovascular findings (NCACVF) in survival of patients with and without malignancies undergoing clinically indicated non-gated thoracic computed tomography (CT) scans.Materials and methodsBetween August and December 2012, a total of 1.901 patients aged between 35 and 74 years underwent clinically indicated non-gated, non-enhanced thoracic CT scans and followed for mortality through September 2016.ResultsThree hundred and thirty two (17.5%), 250 (13.2%), and 329 (17.3%) patients showed CAC in 1, 2, and 3 vessels, respectively, and the remaining had no CAC. Two hundred and fifty five (13.4%) patients had evidence of extensive calcification (CACSIS > 5). Only 62 (3.3%) had major NCACVF whereas 1635 (86%) had none or minimal NCACVF. After a median follow-up of 3.7 (3.5–3.9) years, 217 (11.4%) deaths occurred. Age [HR 1.03 (95% CI 1.01–1.05), p = 0.001], a history of malignancy [HR 8.04 (95% CI 5.95-10.9), p < 0.0001], and the NCACVF class [HR 1.79 (95% CI 1.45-2.19), p < 0.0001] were identified as independent predictors of death. CACSIS was found an independent predictor of death only among patients without malignancy (HR 1.10 (95% CI 1.02–1.20), p = 0.019).ConclusionsIn this study including clinically indicated non-gated standard thoracic CT scans, survival rates were associated to the CAC extension among patients without malignancy, and to the NCACVF class independent from the malignancy status.     

Impact of advanced modeled iterative reconstruction on interreader agreement in coronary artery measurements

ObjectivesTo evaluate the influence of advanced modeled iterative reconstruction (ADMIRE) on coronary artery computed tomography angiography (cCTA) measurements in comparison to filtered back projection (FBP).Material and methodsPhantom scans and coronary CTA studies of 27 patients were acquired with a third generation dual-source CT scanner. Images were reconstructed using FBP and ADMIRE. Phantom measurements were used as reference standard. In patient studies, representative axial slices of each coronary artery segment without (n = 308) and with coronary plaques (n = 40) were assessed in identical positions for comparison of FBP and ADMIRE reconstructions. Image analyses included quality assessment, phantom and coronary artery measurements, plaque analysis, and interreader agreement of two independent and blinded readers.ResultsMean image noise was lower on ADMIRE reconstructions with 31.3 ± 9.9 HU compared to 55.9 ± 15.7 HU on FBP reconstructions (p < 0.001). Measurement precision and interreader agreement of both observers were assessed satisfactorily on phantom images in comparison to the full width half maximum method. In patients, correlation of lumen diameters of both observers improved using ADMIRE with a Pearson’s r = 0.987 (95% confidence interval [CI], 0.983–0.989; p < 0.001) compared to FBP images with r = 0.939 (95% CI, 0.924–0.951; p < 0.001). Applying ADMIRE, agreement of both observers for lumen diameter measurements significantly increased (p < 0.001). This was also observed for the degree of stenosis (p < 0.001) with r = 0.560 using FBP (95% CI, 0.301–0.742) and with r = 0.818 using ADMIRE (95% CI, 0.680–0.900). Plaque density measurements correlated closely with a Pearson’s r of 0.951 in FBP (95% CI, 0.909–0.974) and 0.967 in ADMIRE (95% CI, 0.939–0.983).ConclusionsAdvanced modeled iterative reconstruction significantly improves coronary artery assessment in coronary CTA in comparison to FBP by improved image quality due to image noise removal. This renders improved interobserver agreement for coronary lumen diameter and degree of stenosis measurements without influencing mean plaque attenuation.     

The dilatation of main pulmonary artery and right ventricle observed by enhanced chest computed tomography predict poor outcome in inoperable chronic thromboembolic pulmonary hypertension

BackgroundDilatation of the pulmonary artery and right ventricle on chest computed tomography images is often observed in patients with pulmonary hypertension. The clinical significance of these image findings has not been defined in chronic thromboembolic pulmonary hypertension. We investigated whether the pulmonary arterial and right ventricle dilatation was associated with poor outcome in chronic thromboembolic pulmonary hypertension.MethodsThis was a retrospective cohort investigation in 60 subjects with inoperable chronic thromboembolic pulmonary hypertension diagnosed consecutively between 1997 and 2010 at Chiba University Hospital. Digital scout multi-detector chest computed tomography images were obtained. The main pulmonary arterial to ascending aortic diameter ratio and the right ventricular to left ventricular diameter ratio were calculated.ResultsMain pulmonary arterial to ascending aortic diameter ratio ranged from 0.85 to 1.84, and right ventricular to left ventricular diameter ratio ranged from 0.71 to 2.88. During the observation period of 1284.5 days (range, 21–4550 days), 13 patients required hospitalization due to worsening; 6 of them died. Kaplan–Meier analysis showed significant differences in hospitalization between the patients with main pulmonary arterial to ascending aortic diameter ratio of ≥1.1 and <1.1 (log-rank test, p = 0.014) and between the patients with right ventricular to left ventricular diameter ratio of ≥1.2 and <1.2 (log-rank test, p = 0.013). There was a significant difference in the prognosis between the patients with RV/LV ratio ≥ 1.2 and those with RV/LV ratio < 1.2 (log-rank test, p = 0.033).ConclusionsMain pulmonary arterial to ascending aortic diameter ratio measured using enhanced CT images was associated with the risk for first clinical exacerbation, and right ventricular to left ventricular diameter ratio was associated with the risk for poor prognosis in inoperable chronic thromboembolic pulmonary hypertension.     

Dual-source CT coronary angiography: Diagnostic accuracy without the use of B blockers

PurposeTo evaluate the effect of heart rate, heart rate variability on dual-source computed tomography image quality performed without the use of B blockers and to assess diagnostic accuracy of dual-source CT (using adaptive electrocardiographic pulsing) for coronary artery stenosis, by using invasive coronary angiography as the reference standard.Materials and methodsPatients were studied without β-blocker pre-medication. Unenhanced CT and CT coronary angiography with adaptive ECG pulsing were performed using DSCT (DEFINITION, Siemens Medical Solutions, Forchheim, Germany). A contrast-enhanced volume dataset was acquired (two tubes, 120 kV, 400 mAs/rot, collimation 64 × 0.6 mm). Fifty-one patients (11 women, 40 men; mean age, 60.5 years ± 10 [standard deviation]) known to have or suspected of having coronary artery disease underwent dual-source CT and invasive coronary angiography. Accuracy of dual-source CT in depiction or exclusion of significant stenosis (?50%) was evaluated on a per-segment and per-patient basis. Effects of heart rate, heart rate variability were assessed. Patients were divided in three HRF groups: low, intermediate, and high (?65, 66–79, and ?80 beats/min, respectively), and four HRV groups given mean inter beat difference (IBD) during CT coronary angiography: normal, minor, moderate, and severe (IBDs of 0–1, 2–3, 4–10, and >10, respectively). The diagnostic performance was presented as sensitivity, specificity, positive predictive values, and negative predictive values validated against invasive coronary angiography (?50% lumen diameter reduction).ResultsGood image quality was achieved in 98% of patients without the use of B blockers and no significant differences in image quality were found among HRF and HRV groups. Twenty-three patients were examined having a heart rate ?65 beats/min, image quality was sufficient for diagnosis in 281 of 312 coronary segments (92%), whereas in 28 patients with a heart rate <65 beats/min, the image quality was sufficient for diagnosis in 387 of 388 coronary segments (100%). On a per-patient basis, 93% of patients (?65 beats/min) and 100% of patients (<65 beats/min) were considered evaluable. None of these differences were statistically significant. Similarly, no difference in diagnostic accuracy was found in per-vessel and -segment analyses.ConclusionIn 51 patients studied without β-blocker pre-medication, the overall image quality of dual-source CT coronary angiography is sufficient for diagnosis within a wide range of mean heart rates and variability of heart rates. Only heart rates that are both high and variable significantly deteriorate image quality, but the quality remains adequate for diagnosis.     

Echocardiographic study of early left ventricular remodeling in highly trained preadolescent footballers

Almost all the studies of athlete's heart have been carried out on adult and older adolescent players; hence the limited data on the cardiac response to exercise in the beginning of the active sports career in the youngest athletes. The study was designed to examine the physiological limits of left ventricle (LV) cavity size and wall thickness in elite footballers at the preadolescent age, it the beginning of the active sports career. Ninety-four highly trained male footballers (mean aged 12.85 ± 0.84) competing in the Serbian Football League and 47 age-matched healthy male controls, aged 12–14, were enrolled in the study. All the echocardiographic findings were adjusted to BSA^?0.5, while left ventricle mass (LVM) was additionally adjusted to BSA^?1.5. Reference ranges were defined as values of 5–95th centile according to the mean values in both groups. The proportions of the footballers with LV dimensions outside expected ranges were additionally noted. The data indicate significant increases in absolute values of LV dimensions, aortic root size and left atrium (p < 0.001) in preadolescent professional footballers compared with the values expected for age-matched controls, whereas there are no differences in absolute values of ventricular septal and posterior wall thickness, LV wall thickness and LVM (p > 0.05). Upon body-size adjustments, significant increases were observed in all echocardiographic parameters (p < 0.001). Our data indicate an early cardiac remodeling, already apparent in preadolescence, even after a short period of training.     

Left and right atrial feature tracking in acute myocarditis: A feasibility study

PurposeThe present study aims at evaluating the feasibility and reproducibility of cardiac magnetic resonance (CMR) feature tracking (FT) derived strain and strain rate (SR) parameters of the left and right atrium (LA, RA) in patients with acute myocarditis as well as their potential to detect diastolic dysfunction. In addition, the diagnostic value of LA and RA strain parameters in the setting of acute myocarditis is investigated.MethodsCMR cine data of 30 patients with CMR-positive acute myocarditis were retrospectively analyzed. 25 age- and gender-matched healthy individuals served as a control. Analysis of longitudinal strain and SR of both atria was performed in two long-axis views using a dedicated FT-software. LA and RA deformation was analyzed including reservoir function (total strain [ε_s], peak positive SR [SR_s]), conduit function (passive strain [ε_e], peak early negative SR [SR_e]) and booster pump function (active strain [ε_a], peak late negative SR [SR_a]). Intra- and inter-observer reproducibility was assessed for all strain and SR parameters using Bland-Altman analyses, intra-class correlation coefficients (ICCs) and coefficients of variation (CV).ResultsFT analyses of both atria were feasible in all patients and controls. Reproducibility was good for reservoir and conduit function parameters and moderate for booster pump function parameters. Myocarditis patients demonstrated an impaired LA reservoir and conduit function when compared to healthy controls (LA ε_s: 32 ± 17 vs. 46 ± 13, p = 0.019; LA SR_s: 1.5 ± 0.5 vs. 1.8 ± 0.5, p = 0.117; LA SR_e: −1.3 ± 0.5 vs. −1.9 ± 0.5, p < 0.001), while LA booster pump function was preserved. In logistic regression and ROC-analyses, LA SR_e proved to be the best independent predictor of acute myocarditis (AUC 0.80), and using LA SR_e with a cut-off of −1.6 s⁻¹ resulted in a diagnostic sensitivity of 83% and a specificity of 80%. Changes in RA phasic function parameters showed a tendency to parallel those of the LA and showed no additional effect with respect to the diagnostic potential in acute myocarditis.ConclusionsMyocarditis patients exhibit an impaired atrial reservoir and conduit function, what might be indicative of ventricular diastolic dysfunction. LA SR_e was the best predictor for the presence of acute myocarditis in our study, pointing towards the discriminative power of atrial strain analysis in the CMR-based diagnosis of acute myocarditis.     

A new method for measuring coronary artery diameters with CT spatial profile curves

PurposeCoronary artery vascular edge recognition on computed tomography (CT) angiograms is influenced by window parameters. A noninvasive method for vascular edge recognition independent of window setting with use of multi-detector row CT was contrived and its feasibility and accuracy were estimated by intravascular ultrasound (IVUS).MethodsMulti-detector row CT was performed to obtain 29 CT spatial profile curves by setting a line cursor across short-axis coronary angiograms processed by multi-planar reconstruction. IVUS was also performed to determine the reference coronary diameter. IVUS diameter was fitted horizontally between two points on the upward and downward slopes of the profile curves and Hounsfield number was measured at the fitted level to test seven candidate indexes for definition of intravascular coronary diameter. The best index from the curves should show the best agreement with IVUS diameter.ResultsOf the seven candidates the agreement was the best (agreement: 16 ± 11%) when the two ratios of Hounsfield number at the level of IVUS diameter over that at the peak on the profile curves were used with water and with fat as the background tissue. These edge definitions were achieved by cutting the horizontal distance by the curves at the level defined by the ratio of 0.41 for water background and 0.57 for fat background.ConclusionsVascular edge recognition of the coronary artery with CT spatial profile curves was feasible and the contrived method could define the coronary diameter with reasonable agreement.     

Biventricular mechanics in prediction of severe myocardial fibrosis in patients with dilated cardiomyopathy: CMR study

PurposeThe purpose of this study was to compare the ability of various parameters of myocardial mechanics to predict large amounts of biventricular fibrosis assessed via T1 mapping in patients with dilated cardiomyopathy (DCM).MaterialCardiovascular magnetic resonance feature tracking analysis and T1 mapping were performed in 26 patients with DCM [mean age: 34.4 ± 9.1 years, 15 (57.6%) males]. The values of various parameters of myocardial mechanics at predicting advanced left-ventricle (LV) and right-ventricle (RV) fibrosis were compared using logistic regression analysis and receiver operating characteristic curve (ROC) analysis.ResultsThere were 7 (26.9%) patients with a large amount of LV fibrosis and 9 (34.6%) patients with severe RV fibrosis.ROC curve analysis revealed that the model of combined LV strain rates (AUC = 0.902) offered superb ability at predicting large amounts of LV fibrosis. The models including RV strain rates (AUC = 0.974), a combination of RV strains, strain rates and clinical parameters (AUC = 0.993) as well as the RV radial strain rate alone model (AUC = 0.961) yielded outstanding performance in discriminating large and small amounts of RV fibrosis.In multivariate analysis, the LV circumferential strain (LVCR) and RV radial (RVR) strain rate were the only independent predictors of large amounts of LV and RV fibrosis, respectively.ConclusionsIndices of myocardial deformation, especially combined with clinical features, offered a superlative ability to differentiate high from low degrees of fibrosis in DCM patients. Among all analyzed parameters of myocardial mechanics, LVCR and RVR rate alone were the independent predictors of high degrees of LV and RV fibrosis, respectively.     

New CT criteria for nodal staging in non-small cell lung cancer

ObjectiveThe purpose of our study was to develop a simple noninvasive technique for nodal staging using routine preoperative computed tomography (CT).Materials and methodsThe institutional review board approved this retrospective study, and written informed consent to perform the initial and follow-up CT studies was obtained from all patients. Preoperative CT findings (n= 218 patients with resectable non-small cell lung cancer) and pathological diagnoses after surgical resection were evaluated. Using CT images, lymph node section area, circumference, and lesion attenuation values (LAVs) were drawn freehand, and the short axis (SA) and long axis (LA) were measured using caliper software. Receiver operating characteristic (ROC) curves were then used to analyze the section area, circumference, and LAVs.ResultsBased on ROC curves, two cut-off values, lymph node section area > 30 mm² and circumference > 25 mm, showed greater sensitivity for nodal staging than the conventional criterion of lymph node SA ≥ 10 mm or the LA, SA/LA ratio or LAVs. Using lymph node section area > 30 mm² for diagnosis, the sensitivity, specificity, and accuracy of nodal staging were 90.5%, 56.3%, and 58.3%, respectively. Using lymph node circumference > 25 mm, the values were 76.2%, 70.4%, and 70.8%, respectively.ConclusionLymph node section area > 30 mm² and circumference > 25 mm can serve as supportive criteria used by radiologists and surgeons to determine nodal staging. If these CT criteria are met, use of a more sensitive procedure such as positron emission tomography or mediastinoscopy is recommended.Concise abstractCT is used routinely during preoperative management of lung cancer. Based on ROC analyses, the cut-off values for surface area, circumference, the SA/LA ratio, and LAVs for diagnosis of lymph node metastasis were 30 mm², 25 mm, 0.65, and 50 Hounsfield units, respectively. Our findings indicate that lymph node surface area > 30 mm² and circumference > 25 mm are supportive criteria that can be used by radiologists and thoracic surgeons to determine nodal staging and surgical indications.     

Differentiation of small intrahepatic mass-forming cholangiocarcinoma from small liver abscess by dual source dual-energy CT quantitative parameters

PurposeTo investigate the use of dual source dual-energy CT (DECT) quantitative parameters compared with the use of conventional CT for differentiating small (≤3 cm) intrahepatic mass-forming cholangiocarcinoma (IMCC) from small liver abscess (LA) during the portal venous phase (PVP).Material and methodsIn this institutional review board-approved, retrospective study, 64 patients with IMCCs and 52 patients with LAs who were imaged in PVP using dual-energy mode were included retrospectively. A radiologist drew circular regions of interest in the lesion on the virtual monochromatic images (VMI), color-coded iodine overlay images, and linear blending images with a linear blending ratio of 0.3 to obtain CT value, its standard deviation, slope (k) of spectral curve and normalized iodine concentration (NIC). Two radiologists assessed lesion type on the basis of qualitative CT imaging features.ResultsCT values on VMI at 50–130 keV (20 keV-interval), k, and NIC values were significantly higher in IMCCs than in LAs (p < 0.0001). The best single parameter for differentiating IMCC from LA was CT value at 90 keV, with sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of 89.1%, 86.5%, 87.9%, 89.1%, and 86.5%, respectively. The best combination of parameters was CT value at 90 keV, k, and NIC, with values of 87.5%, 84.6%, 83.6%, 87.5%, and 84.6%, respectively. Compared with CT value at linear blending images, CT value at 90 keV showed greater sensitivity (89.1% vs 60.9%, p < 0.0001) and similar specificity (86.5% vs 84.6%, p = 1.0000), and combined CT value at 90 keV, k, and NIC showed greater sensitivity (87.5% vs 60.9%, p < 0.0001) and similar specificity (84.6% vs 84.6%, p = 1.0000). Compared with qualitative analysis, CT value at 90 keV showed greater sensitivity (89.1% vs 65.6%, p = 0.0059) and specificity (86.5% vs 69.2%, p = 0.0352), and combined CT value at 90 keV, k, and NIC showed greater sensitivity (87.5% vs 65.6%, p = 0.0094) and similar specificity (84.6% vs 69.2%, p > 0.05).ConclusionQuantitative analysis of dual source dual-energy CT quantitative parameters showed greater accuracy than quantitative and qualitative analyses of conventional CT for differentiating small IMCCs from small LAs on single PVP scan.     

CT angiography for planning transcatheter aortic valve replacement using automated tube voltage selection: Image quality and radiation exposure

PurposeTo assess image quality and accuracy of CT angiography (CTA) for transcatheter aortic valve replacement (TAVR) planning performed with 3rd generation dual-source CT (DSCT).Material and methodsWe evaluated 125 patients who underwent TAVR-planning CTA on 3rd generation DSCT. A two-part protocol was performed including retrospectively ECG-gated coronary CTA (CCTA) and prospectively ECG-triggered aortoiliac CTA using 60 mL of contrast medium. Automated tube voltage selection and advanced iterative reconstruction were applied. Effective dose (ED), signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were calculated. Five-point scales were used for subjective image quality analysis. In patients who underwent TAVR, sizing parameters were obtained.ResultsImage quality was rated good to excellent in 97.6% of CCTA and 100% of aortoiliac CTAs. CTA studies at >100 kV showed decreased objective image quality compared to 70–100 kV (SNR, all p ≤ 0.0459; CNR, all p ≤ 0.0462). Mean ED increased continuously from 70 to >100 kV (CCTA: 4.5 ± 1.7 mSv–13.6 ± 2.9 mSv, all p ≤ 0.0233; aortoiliac CTA: 2.4 ± 0.9 mSv–6.8 ± 2.7 mSv, all p ≤ 0.0414). In 39 patients TAVR was performed and annulus diameter was within the recommended range in all patients. No severe cardiac or vascular complications were noted.Conclusion3rd generation DSCT provides diagnostic image quality in TAVR-planning CTA and facilitates reliable assessment of TAVR device and delivery option while reducing radiation dose.     

Coronary risk assessment at X-ray dose equivalent ungated chest CT: Results of a multi-reader study

ObjectivesTo determine the value of ultra-low dose chest CT with tin filtration for ordinal coronary artery calcium (CAC) risk scoring.Methods50 patients were prospectively included and underwent clinical standard dose chest CT (1.8 ± 0.7 mSv) and ultra-low dose CT (0.13 ± 0.01 mSv). Four radiologists estimated presence and extent of CAC.ResultsWeighted kappa values for CAC were 0.76–0.97 in standard dose and 0.75–0.95 in ultra-low dose CT (p < 0.001). Good to excellent agreement was observed for CAC ordinal risk assessment, with readers reporting identical risk in 81% of cases.ConclusionCAC risk can be qualitatively assessed from X-ray dose equivalent ungated chest CT.