Comparison of Myocardial Blood Flow Quantification Models for Double ECG Gating Arterial Spin Labeling MRI: Reproducibility Assessment.

BACKGROUND: Arterial spin labeling (ASL) allows non-invasive quantification of myocardial blood flow (MBF). Double-ECG gating (DG) ASL is more robust to heart rate variability than single-ECG gating (SG), but its reproducibility requires further investigation. Moreover, the existence of multiple quantification models hinders its application. Frequency-offset-corrected-inversion (FOCI) pulses provide sharper edge profiles than hyperbolic-secant (HS), which could benefit myocardial ASL. PURPOSE: To assess the performance of MBF quantification models for DG compared to SG ASL, to evaluate their reproducibility and to compare the effects of HS and FOCI pulses. STUDY TYPE: Prospective. SUBJECTS: Sixteen subjects (27 ± 8 years). FIELD STRENGTH/SEQUENCE: 1.5 T/DG and SG flow-sensitive alternating inversion recovery ASL. ASSESSMENT: Three models for DG MBF quantification were compared using Monte Carlo simulations and in vivo experiments. Two models used a fitting approach (one using only a single label and control image pair per fit, the other using all available image pairs), while the third model used a T1 correction approach. Slice profile simulations were conducted for HS and FOCI pulses with varying B0 and B1. Temporal signal-to-noise ratio (tSNR) was computed for different acquisition/quantification strategies and inversion pulses. The number of images that minimized MBF error was investigated in the model with highest tSNR. Intra and intersession reproducibility were assessed in 10 subjects. STATISTICAL TESTS: Within-subject coefficient of variation, analysis of variance. P-value <0.05 was considered significant. RESULTS: MBF was not different across acquisition/quantification strategies (P = 0.27) nor pulses (P = 0.9). DG MBF quantification models exhibited significantly higher tSNR and superior reproducibility, particularly for the fitting model using multiple images (tSNR was 3.46 ± 2.18 in vivo and 3.32 ± 1.16 in simulations, respectively; wsCV = 16%). Reducing the number of ASL pairs to 13/15 did not increase MBF error (minimum = 0.22 mL/g/min). DATA CONCLUSION: Reproducibility of MBF was better for DG than SG acquisitions, especially when employing a fitting model. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 1.

Diagnostic and Prognostic Potential of Multiparametric Renal MRI in Kidney Transplant Patients.

BACKGROUND: Multiparametric MRI provides assessment of functional and structural parameters in kidney allografts. It offers a non-invasive alternative to the current reference standard of kidney biopsy. PURPOSE: To evaluate the diagnostic and prognostic utility of MRI parameters in the assessment of allograft function in the first 3-months post-transplantation. STUDY TYPE: Prospective. SUBJECTS: 32 transplant recipients (54 ± 17 years, 20 females), divided into two groups according to estimated glomerular filtration rate (eGFR) at 3-months post-transplantation: inferior graft function (IGF; eGFR<45 mL/min/1.73 m2 , n = 10) and superior graft function (SGF; eGFR ≥ 45 mL/min/1.73 m2 , n = 22). Further categorization was based on the need for hemodialysis (C1) and decrease in s-creatinine (C2) at 1-week post-transplantation: delayed-graft-function (DGF: n = 4 C1, n = 10 C2) and early graft-function (EGF: n = 28 C1, n = 22 C2). FIELD STRENGTH/SEQUENCE: 3-T, pseudo-continuous arterial spin labeling, T1-mapping, and diffusion-weighted imaging. ASSESSMENT: Multiparametric MRI was evaluated at 1-week in all patients and 3-months after transplantation in 28 patients. Renal blood flow (RBF), diffusion coefficients (ADC, ΔADC, D, ∆ $$ \Delta $$ D, D*, flowing fraction f), T1 and ∆ $$ \Delta $$ T1 were calculated in cortex and medulla. The diagnostic and prognostic value of these parameters, obtained at 3-months and 1-week post-transplantation, respectively, was evaluated in the cortex to discriminate between DGF and EGF, and between SGF and IGF. STATISTICAL TESTS: Logistic regression, receiver-operating-characteristics, area-under-the-curve (AUC), confidence intervals (CIs), analysis-of-variance, t-test, Wilcoxon-Mann-Whitney test, Fisher's exact test, Pearson's correlation. P-value<0.05 was considered significant. RESULTS: DGF patients exhibited significantly lower cortical RBF and f and higher D*. The diagnostic value of MRI for detecting DGF was excellent (AUC = 100%). Significant differences between patients with IGF and SGF were found in RBF, ∆T1 , and ∆D. Multiparametric MRI showed higher diagnostic (AUC = 95.32%; CI: 88%-100%) and prognostic (AUC = 97.47%, CI: 92%-100%) values for detecting IGF than eGFR (AUC = 89.50%, CI: 79%-100%). DATA CONCLUSION: Multiparametric MRI may show high diagnostic and prognostic value in transplanted patients, yielding better results compared to eGFR measurements. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 1.

Multiparametric renal magnetic resonance imaging: A reproducibility study in renal allografts with stable function.

Monitoring renal allograft function after transplantation is key for the early detection of allograft impairment, which in turn can contribute to preventing the loss of the allograft. Multiparametric renal MRI (mpMRI) is a promising noninvasive technique to assess and characterize renal physiopathology; however, few studies have employed mpMRI in renal allografts with stable function (maintained function over a long time period). The purposes of the current study were to evaluate the reproducibility of mpMRI in transplant patients and to characterize normal values of the measured parameters, and to estimate the labeling efficiency of Pseudo-Continuous Arterial Spin Labeling (PCASL) in the infrarenal aorta using numerical simulations considering experimental measurements of aortic blood flow profiles. The subjects were 20 transplant patients with stable kidney function, maintained over 1 year. The MRI protocol consisted of PCASL, intravoxel incoherent motion, and T1 inversion recovery. Phase contrast was used to measure aortic blood flow. Renal blood flow (RBF), diffusion coefficient (D), pseudo-diffusion coefficient (D*), flowing fraction ( f ), and T1 maps were calculated and mean values were measured in the cortex and medulla. The labeling efficiency of PCASL was estimated from simulation of Bloch equations. Reproducibility was assessed with the within-subject coefficient of variation, intraclass correlation coefficient, and Bland-Altman analysis. Correlations were evaluated using the Pearson correlation coefficient. The significance level was p less than 0.05. Cortical reproducibility was very good for T1, D, and RBF, moderate for f , and low for D*, while medullary reproducibility was good for T1 and D. Significant correlations in the cortex between RBF and f (r = 0.66), RBF and eGFR (r = 0.64), and D* and eGFR (r = -0.57) were found. Normal values of the measured parameters employing the mpMRI protocol in kidney transplant patients with stable function were characterized and the results showed good reproducibility of the techniques.

Assessment of Splenic Switch-Off With Arterial Spin Labeling in Adenosine Perfusion Cardiac MRI.

BACKGROUND: In patients with suspected coronary artery disease (CAD), myocardial perfusion is assessed under rest and pharmacological stress to identify ischemia. Splenic switch-off, defined as the stress to rest splenic perfusion attenuation in response to adenosine, has been proposed as an indicator of stress adequacy. Its occurrence has been previously assessed in first-pass perfusion images, but the use of noncontrast techniques would be highly beneficial. PURPOSE: To explore the ability of pseudo-continuous arterial spin labeling (PCASL) to identify splenic switch-off in patients with suspected CAD. STUDY TYPE: Prospective. POPULATION: Five healthy volunteers (age 24.8 ± 3.8 years) and 32 patients (age 66.4 ± 8.2 years) with suspected CAD. FIELD STRENGTH/SEQUENCE: A 1.5-T/PCASL (spin-echo) and first-pass imaging (gradient-echo). ASSESSMENT: In healthy subjects, multi-delay PCASL data (500-2000 msec) were acquired to quantify splenic blood flow (SBF) and determine the adequate postlabeling delay (PLD) for single-delay acquisitions (PLD > arterial transit time). In patients, single-delay PCASL (1200 msec) and first-pass perfusion images were acquired under rest and adenosine conditions. PCASL data were used to compute SBF maps and SBF stress-to-rest ratios. Three observers classified patients into "switch-off" and "failed switch-off" groups by visually comparing rest-stress perfusion data acquired with PCASL and first-pass, independently. First-pass categories were used as reference to evaluate the accuracy of quantitative classification. STATISTICAL TESTS: Wilcoxon signed-rank, Pearson correlation, kappa, percentage agreement, Generalized Linear Mixed Model, Mann-Whitney, Pearson Chi-squared, receiver operating characteristic, area-under-the-curve (AUC) and confusion matrix. SIGNIFICANCE: P value < 0.05. RESULTS: A total of 27 patients (84.4%) experienced splenic switch-off according to first-pass categories. Comparison of PCASL-derived SBF maps during stress and rest allowed assessment of splenic switch-off, reflected in a reduction of SBF values during stress. SBF stress-to-rest ratios showed a 97% accuracy (sensitivity = 80%, specificity = 100%, AUC = 85.2%). DATA CONCLUSION: This study could demonstrate the feasibility of PCASL to identify splenic switch-off during adenosine perfusion MRI, both by qualitative and quantitative assessments. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: 2.

Reduction of motion effects in myocardial arterial spin labeling.

PURPOSE: To evaluate the accuracy and reproducibility of myocardial blood flow measurements obtained under different breathing strategies and motion correction techniques with arterial spin labeling. METHODS: A prospective cardiac arterial spin labeling study was performed in 12 volunteers at 3 Tesla. Perfusion images were acquired twice under breath-hold, synchronized-breathing, and free-breathing. Motion detection based on the temporal intensity variation of a myocardial voxel, as well as image registration based on pairwise and groupwise approaches, were applied and evaluated in synthetic and in vivo data. A region of interest was drawn over the mean perfusion-weighted image for quantification. Original breath-hold datasets, analyzed with individual regions of interest for each perfusion-weighted image, were considered as reference values. RESULTS: Perfusion measurements in the reference breath-hold datasets were in line with those reported in literature. In original datasets, prior to motion correction, myocardial blood flow quantification was significantly overestimated due to contamination of the myocardial perfusion with the high intensity signal of blood pool. These effects were minimized with motion detection or registration. Synthetic data showed that accuracy of the perfusion measurements was higher with the use of registration, in particular after the pairwise approach, which probed to be more robust to motion. CONCLUSION: Satisfactory results were obtained for the free-breathing strategy after pairwise registration, with higher accuracy and robustness (in synthetic datasets) and higher intrasession reproducibility together with lower myocardial blood flow variability across subjects (in in vivo datasets). Breath-hold and synchronized-breathing after motion correction provided similar results, but these breathing strategies can be difficult to perform by patients.

Chest CT-assessed comorbidities and all-cause mortality risk in COPD patients in the BODE cohort.

BACKGROUND AND OBJECTIVE: The availability of chest computed tomography (CT) imaging can help diagnose comorbidities associated with chronic obstructive pulmonary disease (COPD). Their systematic identification and relationship with all-cause mortality have not been explored. Furthermore, whether their CT-detected prevalence differs from clinical diagnosis is unknown. METHODS: The prevalence of 10 CT-assessed comorbidities was retrospectively determined at baseline in 379 patients (71% men) with mild to severe COPD attending pulmonary clinics. Anthropometrics, smoking history, dyspnoea, lung function, exercise capacity, BODE (BMI, Obstruction, Dyspnoea and Exercise capacity) index and exacerbations rate were recorded. The prevalence of CT-determined comorbidities was compared with that recorded clinically. Over a median of 78 months of observation, the independent association with all-cause mortality was analysed. A 'CT-comorbidome' graphically expressed the strength of their association with mortality risk. RESULTS: Coronary artery calcification, emphysema and bronchiectasis were the most prevalent comorbidities (79.8%, 62.7% and 33.9%, respectively). All were underdiagnosed before CT. Coronary artery calcium (hazard ratio [HR] 2.09; 95% CI 1.03-4.26, p = 0.042), bronchiectasis (HR 2.12; 95% CI 1.05-4.26, p = 0.036) and low psoas muscle density (HR 2.61; 95% CI 1.23-5.57, p = 0.010) were independently associated with all-cause mortality and helped define the 'CT-comorbidome'. CONCLUSION: This study of COPD patients shows that systematic detection of 10 CT-diagnosed comorbidities, most of which were not detected clinically, provides information of potential use to patients and clinicians caring for them.

Single-Cell RNA Sequencing Analysis Reveals a Crucial Role for CTHRC1 (Collagen Triple Helix Repeat Containing 1) Cardiac Fibroblasts After Myocardial Infarction.

BACKGROUND: Cardiac fibroblasts (CFs) have a central role in the ventricular remodeling process associated with different types of fibrosis. Recent studies have shown that fibroblasts do not respond homogeneously to heart injury. Because of the limited set of bona fide fibroblast markers, a proper characterization of fibroblast population heterogeneity in response to cardiac damage is lacking. The purpose of this study was to define CF heterogeneity during ventricular remodeling and the underlying mechanisms that regulate CF function. METHODS: Collagen1α1-GFP (green fluorescent protein)-positive CFs were characterized after myocardial infarction (MI) by single-cell and bulk RNA sequencing, assay for transposase-accessible chromatin sequencing, and functional assays. Swine and patient samples were studied using bulk RNA sequencing. RESULTS: We identified and characterized a unique CF subpopulation that emerges after MI in mice. These activated fibroblasts exhibit a clear profibrotic signature, express high levels of Cthrc1 (collagen triple helix repeat containing 1), and localize into the scar. Noncanonical transforming growth factor-ß signaling and different transcription factors including SOX9 are important regulators mediating their response to cardiac injury. Absence of CTHRC1 results in pronounced lethality attributable to ventricular rupture. A population of CFs with a similar transcriptome was identified in a swine model of MI and in heart tissue from patients with MI and dilated cardiomyopathy. CONCLUSIONS: We report CF heterogeneity and their dynamics during the course of MI and redefine the CFs that respond to cardiac injury and participate in myocardial remodeling. Our study identifies CTHRC1 as a novel regulator of the healing scar process and a target for future translational studies.

Optimization of pseudo-continuous arterial spin labeling for renal perfusion imaging.

PURPOSE: To evaluate labeling efficiency of pseudo-continuous arterial spin labeling (PCASL) and to find the gradient parameters that increase PCASL robustness for renal perfusion measurements. METHODS: Aortic blood flow was characterized in 3 groups: young healthy volunteers (YHV1), chronic kidney disease (CKD) patients (CKDP), and healthy controls (HCO). PCASL inversion efficiency was evaluated through numeric simulations considering the measured pulsatile flow velocity profiles and off-resonance effects for a wide range of gradient parameters, and the results were assessed in vivo. The most robust PCASL implementation was used to measure renal blood flow (RBF) in CKDP and HCO. RESULTS: Aortic blood velocities reached peak values of 120 cm/s in YHV1, whereas for elderly subjects values were lower by approximately a factor of 2. Simulations and experiments showed that by reducing the gradient average (Gave ) and the selective to average gradient ratio (Gmax /Gave ), labeling efficiency was maximized and PCASL robustness to off-resonance was improved. The study in CKDP and HCO showed significant differences in RBF between groups. CONCLUSION: An efficient and robust PCASL scheme for renal applications requires a Gmax /Gave ratio of 6-7 and a Gave value that depends on the aortic blood flow velocities (0.5 mT/m being appropriate for CKDP and HCO).

Quantification of Myocardial Perfusion With Vasodilation Using Arterial Spin Labeling at 1.5T.

BACKGROUND: Myocardial perfusion is evaluated in first-pass MRI using a gadolinium-based contrast agent, which limits its repeatability and restricts its use in patients with abnormal kidney function. Arterial spin labeling (ASL) is a promising technique for measuring myocardial perfusion without contrast injection. The ratio of stress to rest perfusion, termed myocardial perfusion reserve (MPR), is an indicator of the severity of stenosis in patients with coronary artery disease (CAD). PURPOSE: To quantify perfusion increases with pharmacological vasodilation, explore MPR differences between segments with and without perfusion defects, and examine the correlations between quantitative ASL and semiquantitative first-pass measurements. STUDY TYPE: Prospective. SUBJECTS: Sixteen patients with suspected CAD: 10 classified as "healthy," having normal perfusion on first-pass and no enhancement on late gadolinium enhancement (LGE), and six as "nonhealthy," having hypoperfused segments including ischemic and infarcted. FIELD STRENGTH/SEQUENCE: Flow-sensitive alternating inversion recovery (FAIR) rest-stress cardiac ASL with balanced steady-state free precession (bSSFP), rest-stress first-pass imaging using gradient-echo and LGE using a phase-sensitive inversion-recovery bSSFP at 1.5T. ASSESSMENT: For healthy subjects, rest-stress perfusion data were compared in global, coronary artery territory, and segment regions of interest (ROIs). A segmental MPR comparison was performed between normal segments from healthy subjects and abnormal segments from nonhealthy subjects. Correlations between ASL and first-pass parameters were explored. STATISTICAL TESTS: Wilcoxon-signed-rank test, nonparametric factorial analysis of variance (ANOVA), and Pearson's/Spearman's correlations. RESULTS: Perfusion increases were significant globally (P = 0.005), per coronary artery territory (P = 0.015), and per segment (P = 0.03 for all segments in ASL and first-pass, except anteroseptal in ASL P = 0.04). MPR differences between normal and abnormal segments were significant (P = 0.0028: ASL, P = 0.033: first-pass). ASL and first-pass measurements were correlated (MPR: r = 0.64, P = 0.008 and perfusion: rho = 0.47, P = 0.007). DATA CONCLUSION: This study demonstrates the feasibility of ASL to detect hyperemia, the potential to differentiate segments with and without perfusion defects, and significant correlations between ASL and semiquantitative first-pass. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 1.

Long-Term Prognostic Value of Coronary CTA in Orthotopic Heart Transplant Recipients.

OBJECTIVE. This study aimed to evaluate the long-term prognostic value of coronary CTA (CCTA) in heart transplant recipients. MATERIALS AND METHODS. The records of 114 patients who had undergone a heart transplant (mean age, 61.7 ± 11.1 [SD] years; 83.3% men) and who underwent CCTA for the surveillance of coronary allograft vasculopathy (CAV) from June 2007 to December 2017 were retrospectively evaluated for the occurrence of major adverse cardiovascular events (MACEs) (cardiac death, nonfatal myocardial infarction, unstable angina requiring hospitalization, coronary revascularization, cardiac arrhythmias, stroke, and retransplant). Patients were classified according to the presence of nonobstructive CAV (lumen reduction < 50%) or obstructive disease (lumen reduction ≥ 50%) and using a coronary segment involvement score (SIS). Differences in MACE rate between groups were compared. RESULTS. Obstructive CAV was observed in 12 heart transplant recipients (10.5%). During a mean follow-up of 67.5 ± 41.4 months the overall rates of MACE were 50% and 14.7% in patients with obstructive and nonobstructive CAV, respectively (p < .05), resulting in an odds ratio for MACE of 6 (95% CI, 1.7-21.2). Comparison of event-free survival showed a hazard ratio (HR) of 5 (95% CI, 1.95-13; p =. 004) for patients with obstructive disease. The presence of four or more stenotic coronary segments (SIS ≥ 4) was associated with a higher rate of events (HR, 3.46; 95% CI, 1.46-8.23). CONCLUSION. In patients who have undergone a heart transplant, CCTA offers a significant long-term prognostic impact on the prediction of MACEs.

Systolic High-Pitch Coronary CT Angiography for Evaluation of the Coronary Arteries in Heart Transplant Recipients.

OBJECTIVE. The purpose of this study was to evaluate the feasibility, image quality, and radiation dose of high-pitch coronary CT angiography (CCTA) in orthotopic heart transplant (OHT) recipients. SUBJECTS AND METHODS. Twenty-two consecutive OHT recipients (16 men, six women; median age, 66.5 years [interquartile range, 51.3-70.3 years]; median heart rate, 91 beats/min [interquartile range, 79.3-97.3 beats/min]) underwent CCTA with a third-generation dual-source CT scanner in high-pitch mode to rule out coronary allograft vasculopathy. Data acquisition was triggered at 30% of the R-R interval. Two independent observers blindly assessed image quality on a per-segment, per-vessel, and per-patient basis using a 4-point scale (4, excellent; 1, not evaluative). Scores 2-4 indicated diagnostic quality. Studies were compared with previously performed retrospective ECG-gated examinations, when available. Interobserver agreement on the image quality was assessed with kappa statistics. Radiation dose was recorded. RESULTS. A total of 322 coronary segments were evaluated. Diagnostic image quality was observed in 97.5% of the segments. Interobserver agreement for image quality assessment was very good on a per-patient (κ = 0.82), per-vessel (κ = 0.83), and per-segment basis (κ = 0.89). The median per-patient image quality score was 4.0 (3.0-4.0) for the entire coronary tree. A comparison of image quality scores between high-pitch and retrospective ECG-gated CCTA examinations showed no significant differences, but the estimated mean radiation dose was significantly lower for the high-pitch mode (median dose-length product, 31.6 mGy × cm [interquartile range, 23.1-38.8 mGy × cm] vs 736.5 mGy × cm [interquartile range, 655.5-845.7 mGy × cm], p < 0.001). CONCLUSION. Performing single-heartbeat high-pitch CCTA during the systolic phase of the cardiac cycle in OHT recipients results in diagnostic image quality in coronary angiograms at very low radiation dose.

Optimal repetition time for free breathing myocardial arterial spin labeling.

The aim of this study was to improve the scan efficiency of ASL in the myocardium. Free breathing FAIR-ASL scans with different TRs were compared, while keeping the acquisition time constant. Scans were named by the trigger pulse that started each acquisition: every two (TP1), four (TP2) and six (TP3) cardiac cycles. TP2 offered the best alternative with a coefficient of variation of 17.15% intrasession and 36.85% intersession. Mean MBF increased by 0.22 ± 0.41 ml/g/min with mild stress.

Arterial spin labeling (ASL) offers a noninvasive and repeatable measurement of tissue blood flow, but its application in the human heart is still challenging. The aim of this study was to improve the scan efficiency of flow-sensitive alternating inversion recovery (FAIR) ASL using a single inversion time. First, by evaluating a free breathing acquisition without navigators. Second, by shortening TR to acquire more ASL pairs. A FAIR ASL with balanced steady state free precession (bSSFP) readout was implemented at 3 T and tested in 14 healthy volunteers. Three cardiac-triggered ASL scans with different TRs were compared while maintaining a constant acquisition time. These scans were named by the trigger pulse (TP) that started each acquisition: every two (TP1), four (TP2) and six (TP3) cardiac cycles. Two studies were performed on different days to assess the reproducibility of TP2 and TP3 scans. Perfusion response during passive leg raising was also evaluated. Student t-test and nonparametric equivalent were computed for perfusion differences. Bland-Altman and coefficient of variation (CV) were calculated for the reproducibility assessment. Mean myocardial blood flow (MBF) values measured at rest were: 1.47 ± 0.91 ml/g/min (TP1), 1.95 ± 0.93 ml/g/min (TP2) and 1.94 ± 1.41 ml/g/min (TP3). Intrasession CV was 17.15% (TP2) and 24.17% (TP3) and intersession CV was 36.86% (TP2) and 18.38% (TP3). Mean MBF was found to increase with passive stress by 0.22 ± 0.41 ml/g/min for TP2 (P = 0.037). Mean MBF values were consistent with the literature, although in the high end of the normal range. The lower MBF values measured in TP1 scans are attributable to saturation of blood outside the slice because of shorter TR. Free breathing FAIR cardiac ASL without navigators is feasible. A TR of approximately four seconds (TP2) offers the best alternative with similar mean ASL and tSNR than longer TR acquisitions.

Quantitative assessment of left ventricular size and function in cardiac transplant recipients: Side-by-side comparison of real time two-dimensional echocardiography, contrast-enhanced two-dimensional echocardiography, three-dimensional echocardiography, and contrast-enhanced three-dimensional echocardiography as compared to magnetic resonance imaging.

INTRODUCTION: We evaluate the ability of 2D non-contrast-enhanced echocardiography (CE-echo), 2DCE-echo, 3D-echo, 3D non-CE-echo, and 3DCE-echo to evaluate allograft function and dimensions in orthotropic heart transplantation (OHT). Cardiac resonance (CMR) was used as reference. METHODS: Twenty six consecutive OHT-recipients were prospectively recruited. Bland-Altman, Spearman rank, and concordance-correlation coefficients (CCC) were determined. RESULTS: Good CCCs were found between the four modalities and CMR for ejection fraction (r ≥ 0.72/P < 0.001; r ≥ 0.77/ P < 0.001; r ≥ 0.51/ P < 0.23; r ≥ 0.75/ P < 0.001, respectively). Highest intraclass correlation coefficient (ICC) was for 2D CE-echo(CCC = 0.77). End-diastolic volume(EDV) measurements statistically differed when 2D non-CE-echo, 2DCE-echo, and 3D non-CE-echo were compared with the cross-sectional imaging modalities, but they did not differ significantly from 3DCE-echo. End-systolic volume (ESV) and stroke volume (SV) differed statistically between the four modalities; however, SV measured by CMR and 3DCE-echo were comparable. Overall, 2D non-CE-echo, 2DCE-echo, and 3D non-CE-echo showed lower mean EDV, ESV, and SV than CMR. ICC was that of the ESV variable in the 4 techniques, with the values of the ICC of the 3DCE-echo technique superior to the rest. Overall, the best CCC were found for 3DCE(r = 0.88, 0.92 and 0.76 for EDV, ESV and SV, respectively). CONCLUSION: Routine use of 3DCE-echo may allow more comprehensive cardiac assessment in cardiac transplant recipients.

Whole-body computed tomography: a new point of view in a hospital check-up unit? Our experience in 6516 patients.

BACKGROUND: There is a growing awareness that prevention and early diagnosis may reduce the high mortality associated with cancer, cardiovascular and other diseases. The role of whole-body computed tomography (WB-CT) in self-referred and asymptomatic patients has been debated. AIM: To determine frequency and spectrum of WB-CT findings in average-risk subjects derived from a Medical-Check-Up-Unit, to evaluate recommendations reported and distribution according to sex and age-groups. MATERIALS AND METHODS: We retrospectively reviewed 6516 subjects who underwent WB-CT (June 2004/February 2015). All were > 40 years and referred by Medical-Check-Up-Unit of our hospital. The main findings were categorized and classified as normal or not. Its distribution according to sex and age-groups was evaluated using Chi-square test and linear-by-linear association test, respectively. Number of recommendations, type and interval of follow-up were recorded. Descriptive statistics were used. RESULTS: WB-CT performed in 6516 patients (69% men, 31% women, mean age = 58.4 years) revealed chest (81.4%), abdominal (93.06%) and spine (65.39%) abnormalities. Only 1.60% had completely normal exploration. Abnormal WB-CT in men was significantly higher than women (98.64% vs. 97.87%; p = 0.021), with significant increase as age was higher (40-49 years: 95.65%; 50-59 years: 98.33%; 60-69 years: 99.47%; > 69 years: 99.89%) (p < 0.001). Although most findings were benign, we detected 1.47% primary tumors (96, mainly 35 kidneys and 15 lungs). 17.39% of patients received at least one recommendation predominantly in chest (78.19%) and follow-up imaging (69.89%). CONCLUSION: The most common WB-CT findings in asymptomatic subjects are benign. However, this examination allows identifying an important number of relevant and precocious findings that significantly increase with age, involving changes in lifestyle and precocious treatment.

Myocardial Extracellular Volume Quantification by Cardiovascular Magnetic Resonance and Computed Tomography.

PURPOSE OF REVIEW: This review article discusses the evolution of extracellular volume (ECV) quantification using both cardiovascular magnetic resonance (CMR) and computed tomography (CT). RECENT FINDINGS: Visualizing diffuse myocardial fibrosis is challenging and until recently, was restricted to the domain of the pathologist. CMR and CT both use extravascular, extracellular contrast agents, permitting ECV measurement. The evidence base around ECV quantification by CMR is growing rapidly and just starting in CT. In conditions with high ECV (amyloid, oedema and fibrosis), this technique is already being used clinically and as a surrogate endpoint. Non-invasive diffuse fibrosis quantification is also generating new biological insights into key cardiac diseases. CMR and CT can estimate ECV and in turn diffuse myocardial fibrosis, obviating the need for invasive endomyocardial biopsy. CT is an attractive alternative to CMR particularly in those individuals with contraindications to the latter. Further studies are needed, particularly in CT.

European position statement on lung cancer screening.

Lung cancer screening with low-dose CT can save lives. This European Union (EU) position statement presents the available evidence and the major issues that need to be addressed to ensure the successful implementation of low-dose CT lung cancer screening in Europe. This statement identified specific actions required by the European lung cancer screening community to adopt before the implementation of low-dose CT lung cancer screening. This position statement recommends the following actions: a risk stratification approach should be used for future lung cancer low-dose CT programmes; that individuals who enter screening programmes should be provided with information on the benefits and harms of screening, and smoking cessation should be offered to all current smokers; that management of detected solid nodules should use semi-automatically measured volume and volume-doubling time; that national quality assurance boards should be set up to oversee technical standards; that a lung nodule management pathway should be established and incorporated into clinical practice with a tailored screening approach; that non-calcified baseline lung nodules greater than 300 mm3, and new lung nodules greater than 200 mm3, should be managed in multidisciplinary teams according to this EU position statement recommendations to ensure that patients receive the most appropriate treatment; and planning for implementation of low-dose CT screening should start throughout Europe as soon as possible. European countries need to set a timeline for implementing lung cancer screening.

Prospective comparison of non-invasive risk markers of major cardiovascular events in COPD patients.

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is an independent risk factor for cardiovascular (CV) disease, one of the most frequent causes of death in COPD patients. The goal of the present study was to evaluate the prognostic value of non-invasive CV risk markers in COPD patients. METHODS: CV risk was prospectively evaluated in 287 COPD patients using non-invasive markers including the Framingham score, the Systematic Coronary Risk Evaluation (SCORE) charts, coronary arterial calcium (CAC), epicardial adipose tissue (EAT), as well as clinical, biochemical and physiological variables. The predictive power of each parameter was explored using CV events as the main outcome. RESULTS: During a median follow up of 65 months (ICR: 36-100), 44 CV events were recorded, 12 acute myocardial infarctions (27.3%), 10 ischemic heart disease/angina (22.7%), 12 peripheral artery disease events requiring surgery (27.3%) and 10 strokes (22.7%). A total of 35 CV deaths occurred during that period. Univariable analysis determined that age, hypertension, CRP, total Cholesterol, LDL-Cholesterol, Framingham score and CAC were independently associated with CV events. Multivariable analysis identified CAC as the best predictor of CV events (HR; 95%CI: 1.32; 1.19-1.46, p < 001). CONCLUSIONS: In COPD patients attending pulmonary clinics, CAC was the best independent non-invasive predictor of CV events. This tool may help evaluate the risk for a CV event in patients with COPD. Larger studies should reproduce and validate these findings.

Percutaneous CT-Guided Sympathicolysis with Radiofrequency for the Treatment of Palmar Hyperhidrosis.

PURPOSE: To evaluate the benefits of computed tomography (CT)-guided percutaneous sympathicolysis with radiofrequency in patients with primary palmar hyperhidrosis (PPHH) in terms of safety, patient satisfaction, and short- and long-term efficacy. MATERIALS AND METHODS: A total of 139 procedures in 108 patients (mean age, 29.89 y ± 10.94), including 50 men and 58 women, with PPHH and therapy-resistance of nonsurgical treatments were retrospectively analyzed. Treatment was performed bilaterally at T2, T3, and T4 levels, reaching 90°C during 8 minutes. Technical success, immediate efficacy, and presence of complications were analyzed. For follow-up, the Hyperhidrosis Disease Severity Scale was used to evaluate the hyperhidrosis before, at one month, and in the long-term through a survey of 42 patients. Patients' satisfaction and complications were also recorded. RESULTS: The technical success rate was 98.56%. The increase in palmar skin temperature was 4.88°C ± 1.85. A total of 85.3% of participants had completely dry hands immediately after treatment. The mean follow-up time was 41.34 months (range, 6-62 mo). One month after treatment, the response rate was 77.38% (P < .001). At long-term follow-up, the response rate was 69.04% (P < .001). Two major complications were observed (1.8%), 52.38% of patients were satisfied, and 59.52% of patients presented compensatory hyperhidrosis at long-term follow-up. CONCLUSIONS: Percutaneous CT-guided sympathicolysis is a safe and effective technique for the treatment of PPHH and can be considered as a second choice in patients in whom other nonsurgical therapeutic options have failed, despite the compensatory hyperhidrosis rates.

Effect of contrast dose in the quantification of myocardial extra-cellular volume in adenosine stress/rest perfusion cardiac magnetic resonance examinations.

Background Diffuse myocardial fibrosis can be quantified by calculating extra-cellular volume (ECV) from native and post-contrast T1 values using dedicated single bolus contrast medium injection protocols. Purpose To evaluate differences in T1 maps and myocardial ECV measurements in routine stress/rest perfusion cardiovascular magnetic resonance (CMR) examinations after injection of single and double dose of contrast medium. Material and Methods Thirty-seven consecutive patients (30 men; mean age, 62 ± 13 years) underwent clinically indicated adenosine stress/rest perfusion CMR examination to rule out myocardial ischemia following a conventional split-dose contrast medium injection strategy. Native and post-contrast T1 mapping was performed 15 min after the first (0.1 mmol/kg) and second (0.1 mmol/kg) dose of contrast medium using a breath-held Modified Look-Locker Inversion recovery (MOLLI) sequence. Student's t-test for paired samples, Bland-Altman plots, and concordance-correlation coefficients (CCC) for agreement between T1 and ECV calculations after single and double dose of contrast medium were calculated. Intra- and inter-observer agreement for measurements was also analyzed. Results Myocardial T1 values after single and double dose of contrast medium significantly differed (mean difference of 114.1 ± 19.9 ms, P < 0.01). A single dose of contrast agent provided slightly higher ECV values (mean difference of 2.3 ± 1.1%). CCC for ECV calculations was 0.66. Intra- and inter-observer agreement for all measurements was excellent (CCC ≥ 0.83). Conclusion Quantification of myocardial ECV on conventional stress/rest perfusion CMR examination is feasible. T1 maps obtained 15 min after 0.1 mmol/kg of contrast medium provide slightly higher myocardial T1 measurements and ECV values compared with T1 maps obtained after a total dose of 0.2 mmol/kg.

Improving selection criteria for lung cancer screening. The potential role of emphysema.

RATIONALE: Lung cancer (LC) screening using low-dose chest computed tomography is now recommended in several guidelines using the National Lung Screening Trial (NLST) entry criteria (age, 55-74; ≥30 pack-years; tobacco cessation within the previous 15 yr for former smokers). Concerns exist about their lack of sensitivity. OBJECTIVES: To evaluate the performance of NLST criteria in two different LC screening studies from Europe and the United States, and to explore the effect of using emphysema as a complementary criterion. METHODS: Participants from the Pamplona International Early Lung Action Detection Program (P-IELCAP; n = 3,061) and the Pittsburgh Lung Screening Study (PLuSS; n = 3,638) were considered. LC cumulative frequencies, incidence densities, and annual detection rates were calculated in three hypothetical cohorts, including subjects who met NLST criteria alone, those with computed tomography-detected emphysema, and those who met NLST criteria and/or had emphysema. MEASUREMENTS AND MAIN RESULTS: Thirty-six percent and 59% of P-IELCAP and PLuSS participants, respectively, met NLST criteria. Among these, higher LC incidence densities and detection rates were observed. However, applying NLST criteria to our original cohorts would miss as many as 39% of all LC. Annual screening of subjects meeting either NLST criteria or having emphysema detected most cancers (88% and 95% of incident LC of P-IELCAP and PLuSS, respectively) despite reducing the number of screened participants by as much as 52%. CONCLUSIONS: LC screening based solely on NLST criteria could miss a significant number of LC cases. Combining NLST criteria and emphysema to select screening candidates results in higher LC detection rates and a lower number of cancers missed.