Phase-sensitive Inversion Recovery Research Articles

Incremental Prognostic Value of Left Atrial Strain in Patients With Suspected Myocarditis and Preserved Left Ventricular Ejection Fraction.

Analysis of left atrial (LA) strain and left atrioventricular coupling index (LACI) have prognostic value in cardiovascular diseases. However, the prognostic value of LA strain and LACI in patients with suspected myocarditis and preserved left ventricular ejection fraction (LVEF) is unclear. To investigate the prognostic value of LA strain and LACI in patients with suspected myocarditis and preserved LVEF in comparison with conventional MRI outcome predictors. Retrospective. One hundred sixty-five patients with clinically suspected myocarditis and preserved LVEF with available follow-up data. Steady-state free precession cine and phase-sensitive inversion recovery segmented gradient echo late gadolinium enhancement sequences at 3.0 T. Left ventricular (LV) and LA strain were evaluated using feature tracking. LACI was calculated as the ratio of LA and LV volumes at LV end-diastole. Patients were followed-up with the primary endpoint being major adverse cardiovascular events (MACE). Independent-samples t-test and Mann-Whitney U test to compare patients with and without MACE, receiver operating characteristic (ROC) curve analysis to define high/low risk groups, Kaplan-Meier survival analysis and Cox proportional hazards regression to assess prognosis. A P value of <0.05 was considered statistically significant. The associations of LV strain parameters (including global radial, circumferential, and longitudinal strain) and LACI with MACE were not significant (P = 0.511, 0.108, 0.148, and 0.847, respectively). An optimal LA conduit strain (Ԑe) cutoff value of 10.4% was identified to best classify patients into low- and high-risk groups. Only Ԑe was significantly associated with MACE in both univariable (hazards ratio [HR] 0.936, 95% confidence interval [CI] 0.884-0.991) and multivariable Cox survival analyses (HR 0.937, 95% CI 0.884-0.994). LA conduit strain has prognostic value in patients with suspected myocarditis and preserved LVEF, incremental to conventional MRI outcome predictors, whereas LACI was not associated with MACE occurrence. 3 TECHNICAL EFFICACY: Stage 2.

Effect of Metabolic Syndrome on Left Atrial and Left Ventricular Deformation and Atrioventricular Interactions in Patients With Myocardial Infarction.

Metabolic syndrome (MetS) is associated with worse prognosis in patients with myocardial infarction (MI). However, it is unclear how MetS in MI patients is associated with left atrial (LA) and left ventricular (LV) deformation. To determine the effect of MetS on LA and LV deformation and atrioventricular interactions in MI patients. Retrospective. One hundred eighty-one MI patients (73 MetS+ and 108 MetS-), 107 age- and sex-matched controls (49 MetS+ and 58 MetS-). 3.0 T/balanced steady-state free precession (SSFP)/segmented phase-sensitive inversion recovery SSFP sequence. LA strain and strain rates (reservoir, conduit, and active), left atrioventricular coupling index (LACI), and LV geometry and radial, circumferential and longitudinal global peak strains (PS) were compared among groups. Two-way analysis of variance, Spearman and Pearson's correlation coefficients, and multivariable linear regression analysis. P value <0.05 indicated statistical significance. Compared with controls, the MI patients with or without MetS showed impaired LA function (reservoir, conduit, and active) and LV deformation (radial, circumferential, and longitudinal PS) and higher LACI. The MetS+ group had lower LA reservoir and conduit function and LV deformationthan MetS- group. The MetS-MI interaction was not statistically significant. Furthermore, multivariable linear regression showed that MetS was independently associated with LA and LV deformation (β = -0.181 to -0.209) in MI patients; LA function was independently associated with LV circumferential PS (β = 0.230 to 0.394) and longitudinal PS (β = 0.189 to 0.420), and LA passive strain and strain rate were negatively associated with LV mass (β = -0.178 and -0.298). MetS may be associated with the LA and LV dysfunction in MI patients. Impaired LV deformation and LV hypertrophy are independently associated with LA dysfunction in MI patients, and the MI patients have higher LACI than controls, suggesting atrioventricular interaction alterations. 4 TECHNICAL EFFICACY: 3.

Biventricular Impairment and Ventricular Interdependence in Patients With Alcoholic Cardiomyopathy: Insights Through Cardiac Magnetic Resonance Imaging.

Alcoholic cardiomyopathy (ACM) can lead to progressive cardiac dysfunction and heart failure, but little is known about biventricular impairment and ventricular interdependence (VI) in ACM patients. To use cardiac MRI to investigate biventricular impairment and VI in ACM patients. Retrospective. Forty-one male patients with ACM and 45 sex- and age-matched controls. 3.0 T/balanced steady-state free precession sequence, inversion recovery prepared echo-planar imaging sequence and phase-sensitive inversion recovery sequence. Biventricular structure, function, and global strain (encompassing peak strain [PS], peak systolic, and diastolic strain rate), PS of interventricular septal (IVS), microvascular perfusion (including upslope and time to maximum signal intensity [TTM]), late gadolinium enhancement (LGE), and baseline characteristics were compared between the controls and ACM patients. Student's t-test, Mann-Whitney U test, Pearson's correlation, and multivariable linear regression models with a stepwise selection procedure. A two-tailed P value <0.05 was deemed as statistically significant. Compared to control subjects, ACM patients showed significantly biventricular adverse remodeling, reduced left ventricle (LV) global upslope and prolonged global TTM, and the presence of LGE. ACM patients were characterized by a significant decline in all global strain within the LV, right ventricle (RV), and IVS compared with the controls. RV global PS was significantly associated with LV global PS and IVS PS in radial, circumferential, and longitudinal directions. Multivariable analyses demonstrated the longitudinal PS of IVS was significantly correlated with RV global radial PS (β = 0.614) and circumferential PS (β = 0.545). Additionally, RV global longitudinal PS (GLPS) was significantly associated with radial PS of IVS (β = -0.631) and LV GLPS (β = 1.096). ACM patients exhibited biventricular adverse structural alterations and impaired systolic and diastolic function. This cohort also showed reduced LV microvascular perfusion, the presence of LGE, and unfavorable VI. 3 TECHNICAL EFFICACY: Stage 3.

Association of Pulmonary Transit Time and Pulmonary Blood Volume From First-Pass Perfusion Cardiac MRI With Diastolic Dysfunction and Left Ventricle Deformation in Restrictive Cardiomyopathy.

Patients with restrictive cardiomyopathy (RCM) have impaired diastolic filling and hemodynamic congestion. Pulmonary transit time (PTT) and pulmonary blood volume index (PBVi) reflect the hemodynamic status, but the relationship with left ventricle (LV) dysfunction remains unclear. To evaluate the PTT and PBVi in RCM patients, the association with diastolic dysfunction and LV deformation, and the effects on the occurrence of major adverse cardiac events (MACE) in RCM patients. Retrospective. 137 RCM patients (88 men, age 58.80 ± 10.83 years) and 68 age- and sex-matched controls (46 men, age 57.00 ± 8.59 years). 3.0T/Balanced steady-state free precession sequence, recovery prepared echo-planar imaging sequence, and phase-sensitive inversion recovery sequence. The LV function and peak strain (PS) parameters were measured. The PTT was calculated and corrected by heart rate (PTTc). The PBVi was calculated as the product of PTTc and RV stroke volume index. Chi-squared test, student's t-test, Mann-Whitney U test, Pearson's or Spearman's correlation, multivariate linear regression, Kaplan-Meier survival analysis, and Cox regression models analysis. A P-value <0.05 was considered statistically significant. The PTTc showed a significant correlation with the E/A ratio (r = 0.282), and PBVi showed a significant correlation with the E/e' ratio, E/A ratio, and diastolic dysfunction stage (r = 0.222, 0.320, and 0.270). PTTc showed an independent association with LVEF, LV circumferential PS, and LV longitudinal PS (β = 0.472, 0.299, and 0.328). In Kaplan-Meier analysis, higher PTTc and PBVi were significantly associated with MACE. In multivariable Cox regression analysis, PTTc was a significantly independent predictor of the MACE in combination with both cardiac MRI functional and tissue parameters (hazard ratio: 1.23/1.32, 95% confidence interval: 1.10-1.42/1.20-1.46). PTTc and PBVi are associated with diastolic dysfunction and deteriorated LV deformation, and PTTc independently predicts MACE in patients with RCM. 3 TECHNICAL EFFICACY: Stage 2.

Automated assessment of cardiac pathologies on cardiac MRI using T1-mapping and late gadolinium phase sensitive inversion recovery sequences with deep learning

BackgroundA deep learning (DL) model that automatically detects cardiac pathologies on cardiac MRI may help streamline the diagnostic workflow. To develop a DL model to detect cardiac pathologies on cardiac MRI T1-mapping and late gadolinium phase sensitive inversion recovery (PSIR) sequences were used.MethodsSubjects in this study were either diagnosed with cardiac pathology (n = 137) including acute and chronic myocardial infarction, myocarditis, dilated cardiomyopathy, and hypertrophic cardiomyopathy or classified as normal (n = 63). Cardiac MR imaging included T1-mapping and PSIR sequences. Subjects were split 65/15/20% for training, validation, and hold-out testing. The DL models were based on an ImageNet pretrained DenseNet-161 and implemented using PyTorch and fastai. Data augmentation with random rotation and mixup was applied. Categorical cross entropy was used as the loss function with a cyclic learning rate (1e-3). DL models for both sequences were developed separately using similar training parameters. The final model was chosen based on its performance on the validation set. Gradient-weighted class activation maps (Grad-CAMs) visualized the decision-making process of the DL model.ResultsThe DL model achieved a sensitivity, specificity, and accuracy of 100%, 38%, and 88% on PSIR images and 78%, 54%, and 70% on T1-mapping images. Grad-CAMs demonstrated that the DL model focused its attention on myocardium and cardiac pathology when evaluating MR images.ConclusionsThe developed DL models were able to reliably detect cardiac pathologies on cardiac MR images. The diagnostic performance of T1 mapping alone is particularly of note since it does not require a contrast agent and can be acquired quickly.

Association Between Myocardial Oxygenation and Fibrosis in Duchenne Muscular Dystrophy: Analysis by Rest Oxygenation-Sensitive Magnetic Resonance Imaging.

Myocardial hypoxia has been demonstrated in many cardiomyopathies and is related to development of myocardial fibrosis. However, myocardial hypoxia and its association with myocardial fibrosis are understudied in Duchenne muscular dystrophy (DMD)-associated cardiomyopathy. To evaluate myocardial hypoxia by oxygenation-sensitive (OS) cardiac magnetic resonance imaging, and further explore its association with fibrosis. Prospective. Ninety-one DMD boys (8.78 ± 2.32) and 30 healthy boys (9.07 ± 2.30). 3 T, Balanced steady-state free procession, Modified Look-Locker inversion recovery sequence and Single-shot phase-sensitive inversion recovery sequence. Cardiac MRI data, including left ventricular functional, segmental native T1, and oxygenation signal-intensity (SI) according to AHA 17-segment model, were acquired. Patients were divided into LGE+ and LGE- groups. In patients with LGE, all segments were further classified as positive or negative segments by segmentally presence/absence of LGE. Variables were compared using Student's t, Wilcoxon, Kruskal-Wallis test and one-way analysis of variance. Bivariate Pearson or Spearman correlation were calculated to determine association between oxygenation SI and native T1. Variables with P < 0.10 in the univariable analysis were included in multivariable model. Receiver operating characteristic analysis was used to assess the performance of OS in diagnosing myocardial hypoxia. The myocardial oxygenation SI of DMD was significantly decreased in all segments compared with normal controls, and more obvious in the LGE+ segments (0.46 ± 0.03 vs. 0.52 ± 0.03). For patients with and without LGE, myocardial oxygenation SI were significantly negatively correlated with native T1 in all segments (r = -0.23 to -0.42). The inferolateral oxygenation SI was a significant independent associator of LGE presence (adjusted OR = 0.900). Myocardial hypoxia evaluated by the OS-Cardiac-MRI indeed occurs in DMD and associate with myocardial fibrosis, which might be used as a biomarker in assessing myocardial damage in DMD. 1 TECHNICAL EFFICACY: Stage 1.

Diagnostic Contribution of Additional Sequences to the Evaluation of Cord Lesions in Patients with Cervical Spinal Multiple Sclerosis in Turkey: A Retrospective Study.

Multiple Sclerosis (MS) is the most common cause of non-traumatic disability in young adults. Spinal cord involvement is observed in 55-75% of patients with MS. To identify the strengths and shortcomings of sagittal phase-sensitive inversion recovery (PSIR), sagittal proton density/T2-weighted (PD/T2W), and axial turbo inversion recovery magnitude (TIRM) sequences in the detection of cervical MS plaques by comparing with routine sequences (axial and sagittal T2W, sagittal T1W, sagittal TIRM, fat-suppressed contrast T1W) and therefore determine their diagnostic contributions. A total of 48 patients in whom additional magnetic resonance imaging (MRI) sequences were obtained for the diagnosis of cervical MS were retrospectively identified and included in the study. A total of 111 MS plaques were analyzed in terms of visibility, number, size, border sharpness, and intensity ratio based on the routine and additional MRI sequences. The evaluation of the images was independently undertaken by two radiologists. The highest visibility was provided by sagittal PSIR, sagittal TIRM, and axial TIRM sequences (P < 0.05 for all additional sequences). Seven lesions in PD/T2W and four lesions in axial T2W sequences were unable to be detected. Lesions seen in sagittal and axial TIRM sequences were larger than the others. The sharpest borders were determined in the axial TIRM sequence, and the most diffuse borders in the PD/T2W sequence. In intensity ratio, the sagittal PSIR sequence revealed the most significant contrast difference. The sagittal PSIR sequence may improve the detection of cervical MS plaques due to the improved visibility and intensity ratios. The axial TIRM sequence may be more useful than routine axial T2W in the evaluation of visibility, border sharpness, and size measurement of MS plaques.

Detection of Spinal Cord Multiple Sclerosis Lesions Using a 3D-PSIR Sequence at 1.5 T.

Multiple sclerosis (MS) is aprevalent autoimmune inflammatory disease. Besides cerebral manifestations, an affection of the spinal cord is typical; however, imaging of the spinal cord is difficult due to its anatomy. The aim of this study was to assess the diagnostic value of a3D PSIR pulse sequencing at a1.5 T magnetic field strength for both the cervical and thoracic spinal cord. Phase sensitive inversion recovery (PSIR), short tau inversion recovery (STIR) and T2-weighted (T2-w)images of the spinal cord of 50patients were separately evaluated by three radiologists concerning the number and location of MS lesions. Furthermore, lesion to cord contrast ratios were determined for the cervical and thoracic spinal cord. Of the lesions 54.81% were located in the cervical spinal cord, 42.26% in the thoracic spinal cord and 2.93% in the conus medullaris. The PSIR images showed ahigher sensitivity for lesion detection in the cervical and thoracic spinal cord (77.10% and 72.61%, respectively) compared to the STIR images (58.63% and 59.10%, respectively) and the T2-w images (59.95% and 59.52%, respectively). The average lesion to cord contrast ratio was significantly higher in the PSIR images compared to the STIR images (p < 0.001) and the T2-w images (p < 0.001). Evaluation of the spinal cord with a3D PSIR sequence at amagnetic field strength of 1.5 T is feasible with ahigh sensitivity for the detection of spinal MS lesions for the cervical as well as the thoracic segments. In combination with other pulse sequences it might become avaluable addition in an advanced imaging protocol.

Liver T1 Mapping Derived From Cardiac Magnetic Resonance Imaging: A Potential Prognostic Marker in Idiopathic Dilated Cardiomyopathy.

Hepatic alterations are common aftereffects of heart failure (HF) and ventricular dysfunction. The prognostic value of liver injury markers derived from cardiac MRI studies in nonischemic dilated cardiomyopathy (DCM) patients is unclear. Evaluate the prognostic performance of liver injury markers derived from cardiac MRI studies in DCM patients. Prospective. Three hundred fifty-six consecutive DCM patients diagnosed according to ESC guidelines (age 48.7 ± 14.2 years, males 72.6%). Steady-state free precession, modified Look-Locker inversion recovery T1 mapping and phase sensitive inversion recovery late gadolinium enhancement (LGE) sequences at 3 T. Clinical characteristics, conventional MRI parameters (ventricular volumes, function, mass), native myocardial and liver T1, liver extracellular volume (ECV), and myocardial LGE presence were assessed. Patients were followed up for a median duration of 48.3 months (interquartile range 42.0-69.9 months). Primary endpoints included HF death, sudden cardiac death, heart transplantation, and HF readmission; secondary endpoints included HF death, sudden cardiac death, and heart transplantation. Models were developed to predict endpoints and the incremental value of including liver parameters assessed. Optimal cut-off value was determined using receiver operating characteristic curve and Youden method. Survival analysis was performed using Kaplan-Meier and Cox proportional hazard. Discriminative power of models was compared using net reclassification improvement and integrated discriminatory index. P value <0.05 was considered statistically significant. 47.2% patients reached primary endpoints; 25.8% patients reached secondary endpoints. Patients with elevated liver ECV (cut-off 34.4%) had significantly higher risk reaching primary and secondary endpoints. Cox regression showed liver ECV was an independent prognostic predictor, and showed independent prognostic value for primary endpoints and long-term HF readmission compared to conventional clinical and cardiac MRI parameters. Liver ECV is an independent prognostic predictor and may serve as an innovative approach for risk stratification for DCM. 1 TECHNICAL EFFICACY: Stage 2.

Quality assurance of late gadolinium enhancement cardiac magnetic resonance images: a deep learning classifier for confidence in the presence or absence of abnormality with potential to prompt real-time image optimization

BackgroundLate gadolinium enhancement (LGE) of the myocardium has significant diagnostic and prognostic implications, with even small areas of enhancement being important. Distinguishing between definitely normal and definitely abnormal LGE images is usually straightforward; but diagnostic uncertainty arises when reporters are not sure whether the observed LGE is genuine or not. This uncertainty might be resolved by repetition (to remove artefact) or further acquisition of intersecting images, but this must take place before the scan finishes. Real-time quality assurance by humans is a complex task requiring training and experience, so being able to identify which images have an intermediate likelihood of LGE while the scan is ongoing, without the presence of an expert is of high value. This decision-support could prompt immediate image optimisation or acquisition of supplementary images to confirm or refute the presence of genuine LGE. This could reduce ambiguity in reports. MethodsShort-axis, phase sensitive inversion recovery (PSIR) late gadolinium images were extracted from our clinical CMR database and shuffled. Two, independent, blinded experts scored each individual slice for ‘LGE likelihood’ on a visual analogue scale, from 0 (absolute certainty of no LGE) to 100 (absolute certainty of LGE), with 50 representing clinical equipoise. The scored images were split into 2 classes – either “high certainty” of whether LGE was present or not, or “low certainty”. The dataset was split into training, validation and test sets (70:15:15). A deep learning binary classifier based on the EfficientNetV2 convolutional neural network architecture was trained to distinguish between these categories. Classifier performance on the test set was evaluated by calculating the accuracy, precision, recall, F1-score, and area under the receiver operating characteristics curve (ROC AUC). Performance was also evaluated on an external test set of images from a different centre. Results1645 images (from 272 patients) were labelled and split at the patient level into training (1151 images), validation (247 images) and test (247 images) sets for the deep learning binary classifier. Of these, 1208 images were ‘high certainty’ (255 for LGE, 953 for no LGE), and 437 were ‘low certainty’). An external test comprising 247 images from 41 patients from another centre was also employed. After 100 epochs the performance on the internal test set was: accuracy = 94%, recall = 0.80, precision = 0.97, F1-score = 0.87 and ROC AUC = 0.94. The classifier also performed robustly on the external test set (accuracy = 91%, recall = 0.73, precision = 0.93, F1-score = 0.82 and ROC AUC = 0.91). These results were benchmarked against a reference inter-expert accuracy of 86%. ConclusionsDeep learning shows potential to automate quality control of late gadolinium imaging in CMR. The ability to identify short-axis images with intermediate LGE likelihood in real-time may serve as a useful decision support tool. This approach has the potential to guide immediate further imaging while the patient is still in the scanner, thereby reducing the frequency of recalls and inconclusive reports due to diagnostic indecision.

Associations between cortical lesions, optic nerve damage, and disability at the onset of multiple sclerosis: insights into neurodegenerative processes.

BackgroundMultiple sclerosis cortical lesions are areas of demyelination and neuroaxonal loss. Retinal layer thickness, measured with optical coherence tomography (OCT), is an emerging biomarker of neuroaxonal loss. Studies have reported correlations between cortical lesions and retinal layer thinning in established multiple sclerosis, suggesting a shared pathophysiological process. Here, we assessed the correlation between cortical lesions and OCT metrics at the onset of multiple sclerosis, examining, for the first time, associations with physical or cognitive disability. ObjectiveTo examine the relationship between cortical lesions, optic nerve and retinal layer thicknesses, and physical and cognitive disability at the first demyelinating event. MethodsThirty-nine patients and 22 controls underwent 3T-MRI, optical coherence tomography, and clinical tests. We identified cortical lesions on phase-sensitive inversion recovery sequences, including occipital cortex lesions. We measured the estimated total intracranial volume and the white matter lesion volume. OCT metrics included peripapillary retinal nerve fibre layer (pRNFL), ganglion cell and inner plexiform layer (GCIPL) and inner nuclear layer (INL) thicknesses. ResultsHigher total cortical and leukocortical lesion volumes correlated with thinner pRNFL (B = -0.0005, 95 % CI -0.0008 to -0.0001, p = 0.01; B = -0.0005, 95 % CI -0.0008 to -0.0001, p = 0.01, respectively). Leukocortical lesion number correlated with colour vision deficits (B = 0.58, 95 %CI 0.039 to 1,11, p = 0.036). Thinner GCIPL correlated with a higher Expanded Disability Status Scale (B = -0.06, 95 % CI -1.1 to -0.008, p = 0.026). MS diagnosis (n = 18) correlated with higher cortical and leukocortical lesion numbers (p = 0.004 and p = 0.003), thinner GCIPL (p = 0.029) and INL (p = 0.041). ConclusionThe association between cortical lesions and axonal damage in the optic nerve reinforces the role of neurodegenerative processes in MS pathogenesis at onset.

Abstract 17723: Non-Contrast Cardiac Magnetic Resonance BOOST Whole Heart Acquisition to Evaluate Coronaries in Children and Young Adults

Introduction: Cardiac magnetic resonance (CMR) coronary evaluation remains challenging in teenagers and young adults using conventional respiratory navigation strategies due to irregular respiratory patterns. Motion correction strategies have shown promise in improving efficiency and quality. We sought to evaluate a non-contrast 3D whole-heart sequence with bright-blood (BB) and dark-blood (DB) phase sensitive inversion recovery (BOOST) using image-based navigation (iNAV) and a variable-density cartesian spiral profile order trajectory (VD-CASPR). Hypothesis: BOOST acquisitions improves delineation of coronary origins and proximal courses. Methods: Pts undergoing clinically indicated CMRs were prospectively enrolled and scanned at 1.5T (AVANTO FIT, Siemens) using 2 different imaging methods: 1) BOOST research sequence employing either T2 or magnetization transfer preparation at 1.0-1.4 mm isotropic resolution. When clinically indicated, 2) a standard navigated inversion recovery gradient echo sequence (IR-FLASH) acquired after gadolinium or ferumoxytol infusion. Both coronary imaging methods were rated on a 1-4 scale: 1=non-diagnostic, 2=coronary origins with significant image degradation, 3=mild image degradation, and 4=sharp delineation of the proximal coronaries. A composite BOOST score (highest score between BB and DB images) was compared to IR-FLASH. Group comparisons used a paired t-test (two-tailed, p&lt;0.05). Results: 18 pts, mean age 18.8 years (range=10-31) underwent BOOST imaging. 15 had an IR-FLASH for comparison. BOOST acquisition times were 7-12 minutes. Three pts had coronary anomalies (2 with right coronary from the left sinus, 1 single coronary). Coronary origins were delineated on all BOOST exams with a mean score=3.6 for BB BOOST and 2.9 for DB compared to 3.1 for the IR-FLASH, neither of which was significantly different. The composite BOOST mean score was 3.8, which was significantly higher than IR-FLASH. Conclusions: In our series in children and young adults, contrast-free BOOST imaging delineated coronary origins in all pts, even in challenging cases of anomalous origins. When utilizing both BB and DB BOOST images, image quality exceeded that of a conventional post-contrast IR-FLASH sequence.

3D phase-sensitive inversion recovery sequence for intracranial vertebrobasilar artery dissection

BackgroundT1-weighted 3D turbo spin echo (T1W-3D-TSE) sequences with variable refocusing flip angle are commonly used to diagnose intracranial vertebrobasilar artery dissection (iVAD). However, magnetic susceptibility artifacts of the cavernous sinus may cause loss of the basilar and vertebral arteries. This study investigated the effectiveness of a 3D phase-sensitive inversion recovery (3D-PSIR) sequence in reducing magnetic susceptibility artifacts in the cavernous sinus, and its imaging findings for iVAD. MethodsTwelve volunteers and eleven patients with iVAD were included. Magnetic resonance imaging (MRI) was performed using a 3.0-T MRI system. 3D-PSIR and T1W-3D-TSE sequences were used. Vessel wall defects and contrast-to-noise ratio (CNR) were evaluated. The MRI findings were visually evaluated. ResultsIn the 3D-PSIR images, one volunteer (8 %) had vessel wall defects, and five (42 %) had vessel wall defects (p = 0.046) in the T1W-3D-TSE images. CNR was higher in 3D-PSIR images for vessel wall-to-lumen, whereas it was higher in T1W-3D-TSE images for vessel wall-to-CSF (p < 0.001). Visual evaluation revealed similar MRI findings between the two sequences. ConclusionsThe 3D-PSIR sequence may be able to improve the vessel wall defects and achieve MRI findings comparable to those of the T1W-3D-TSE sequence in iVAD. The 3D-PSIR sequence can be a useful tool for the imaging-based diagnosis of iVAD.

Feasibility of gray-blood late gadolinium enhancement evaluation in young patients with congenital and acquired heart disease.

Late gadolinium enhancement (LGE) sequences have become common in pediatric cardiovascular magnetic resonance (CMR) to assess for myocardial fibrosis. Bright-blood late gadolinium enhancement (BB-LGE) by conventional phase-sensitive inversion recovery (PSIR) is commonly utilized, but similar inversion time (TI) value of fibrosis and left ventricular (LV) blood pool can make subendocardial areas difficult to assess. A gray-blood LGE (GB-LGE) technique has been described, targeting nulling of the LV blood pool and demonstrating improvement in ischemic scar detection over BB-LGE in adult patients. We sought to evaluate the feasibility of the GB-LGE technique in a young population with congenital and acquired heart disease and compare its ability to detect subendocardial scar to conventional BB-LGE. Seventy-six consecutive patients referred for clinical CMR underwent both BB-LGE and GB-LGE on 1.5 T and 3 T scanners. Conventional PSIR sequences were obtained with TI to null the myocardium (BB-LGE) in short-axis and horizontal long-axis stacks. Same PSIR stacks were immediately repeated with TI to null the blood pool (GB-LGE). Both sequences were reviewed separately a week apart by two readers, blinded to the initial clinical interpretation. Studies were analyzed for overall image quality, confidence in scar detection, confidence in detection of LGE, LGE class, inter- and intra-observer agreement for the presence of scar, and intraclass correlation coefficient (ICC) for total scar burden. Overall confidence in myocardial scar detection by BB-LGE or GB-LGE as well as grading of image quality were not statistically different [(p = 1 and p = 1) and (p = 0.53, p = 0.18), respectively]. There was very good inter-observer agreement for the presence of scar on BB-LGE (K = 0.88, 95% CI 0.77-0.99) and GB-LGE (K = 0.84, 95% CI 0.7-0.96), as well as excellent intra-observer agreement for both readers (K = 0.93, 95% CI 0.87-0.99; and K = 0.81, 95% CI 0.69-0.95). Interclass correlation coefficient for total scar burden was excellent for BB-LGE (ICC = 0.98, 95% CI 0.96-0.99) and GB-LGE (ICC = 0.94, 95% CI 0.91-0.97). The GB-LGE technique is feasible in the pediatric population with congenital and acquired heart disease. It can detect subendocardial/ischemic scar similar to conventional bright-blood PSIR sequences in the pediatric population.

Assessment of Pulmonary Arteries Hemodynamics and Its Relationship With Cardiac Remodeling and Myocardial Fibrosis in Athletes With Four-Dimensional Flow MRI.

Exercise-induced cardiac remodeling (CR) and myocardial fibrosis (MF) can increase cardiovascular risk in athletes. Early detection of pulmonary arterial hemodynamics parameters among athletes may be beneficial in optimizing the frequency of clinical follow-ups. To analyze the hemodynamics of pulmonary arteries and its relationship with CR and MF in athletes using four-dimensional (4D) flow MRI. Prospective. One hundred twenty-one athletes (median age, 24 years; mean exercise per week 10 hours, for mean of 5 years) and twenty-onesedentary healthy controls (median age, 25 years; exercise per week <3 hours, irregular pattern). True fast imaging with steady state free precession, time-resolved 3D Cartesian phase-contrast, and phase sensitive inversion recovery late gadolinium enhancement sequences at 3.0 T. CR was defined as any cardiac parameters exceeding the 99th percentile upper reference limits, encompassing ventricular function, bi-atrium and bi-ventricle diameters, and ventricular wall thickness. MF was visually evaluated by three independent radiologists. 4D flow parameters were assessed in the main, right, and left pulmonary arteries (MPA, RPA, and LPA, respectively) and compared between different groups. Four machine learning (ML) models were developed to differentiate between athletes with and without CR and/or MF. Univariate analysis was used to compare groups. Area under the receiver operating characteristic curve (AUC) was used to assess the performance of the ML models. Athletes had significantly higher WSSmax in the MPA, RPA, and LPA than controls. Athletes with CR and/or MF (N = 30) had significantly lower RPmax from MPA to RPA than those without (N = 91). Among the ML models, the gradient boosting machine model had the highest performance, with an AUC of 0.90. The pulmonary arterial hemodynamics parameters could differentiate CR and/or MF in athletes, which may be potential to assist in optimizing frequency of follow-up. 1 TECHNICAL EFFICACY: Stage 2.

Feasibility and image quality of bright-blood and black-blood phase-sensitive inversion recovery (BOOST) sequence in clinical practice using for left atrial visualization in patients with atrial fibrillation

ObjectivesVisualizing left atrial anatomy including the pulmonary veins (PVs) is important for planning the procedure of pulmonary vein isolation with ablation in patients with atrial fibrillation (AF). The aims of our study are to investigate the feasibility of the 3D whole-heart bright-blood and black-blood phase-sensitive (BOOST) inversion recovery sequence in patients with AF scheduled for ablation or electro-cardioversion, and to analyze the correlation between image quality and heart rate and rhythm of patients.MethodsBOOST was performed for assessing PVs both with T2 preparation pre-pulse (T2prep) and magnetization transfer preparation (MTC) in 45 patients with paroxysmal or permanent AF scheduled for ablation or electro-cardioversion. Image quality analyses were performed by two independent observers. Qualitative assessment was made using the Likert scale; for quantitative analysis, signal to noise ratios (SNR) and contrast to noise ratios (CNR) were calculated for each PV. Heart rate and rhythm were analyzed based on standard 12-lead ECGs.ResultsAll MTC-BOOST acquisitions achieved diagnostic quality in the PVs, while a significant proportion of T2prep-BOOST images were not suitable for assessing PVs. SNR and CNR values of the MTC-BOOST bright-blood images were higher if patients had sinus rhythm. We found a significant or nearly significant negative correlation between heart rate and the SNR and CNR values of MTC-BOOST bright-blood images.Conclusion3D whole-heart MTC-BOOST bright-blood imaging is suitable for visualizing the PVs in patients with AF, producing diagnostic image quality in 100% of cases. However, image quality was influenced by heart rate and rhythm.Clinical relevance statementThe novel 3D whole-heart BOOST CMR sequence needs no contrast administration and is performed during free-breathing; therefore, it is easy to use for a wide range of patients and is suitable for visualizing the PVs in patients with AF.Key Points• The applicability of the novel 3D whole-heart bright-blood and black-blood phase-sensitive sequence to pulmonary vein imaging in clinical practice is unknown.• Magnetization transfer-bright-blood and black-blood phase-sensitive imaging is suitable for visualizing the pulmonary veins in patients with atrial fibrillation with excellent or good image quality.• Bright-blood and black-blood phase-sensitive cardiac magnetic resonance sequence is easy to use for a wide range of patients as it needs no contrast administration and is performed during free-breathing.

Synthetic multi-contrast late gadolinium enhancement imaging using post-contrast magnetic resonance fingerprinting.

Late gadolinium enhancement (LGE) MRI is the non-invasive reference standard for identifying myocardial scar and fibrosis but has limitations, including difficulty delineating subendocardial scar and operator dependence on image quality. The purpose of this work is to assess the feasibility of generating multi-contrast synthetic LGE images from post-contrast T1 and T2 maps acquired using magnetic resonance fingerprinting (MRF). Fifteen consecutive patients with a history of prior ischemic cardiomyopathy (12 men; mean age 63 13 years) were prospectively scanned at 1.5 T between Oct 2020 and May 2021 using conventional LGE and MRF after injection of gadolinium contrast. Three classes of synthetic LGE images were derived from MRF post-contrast T1 and T2 maps: bright-blood phase-sensitive inversion recovery (PSIR), black- and gray-blood T2 -prepared PSIR (T2 -PSIR), and a novel "tissue-optimized" image to enhance differentiation among scar, viable myocardium, and blood. Image quality was assessed on a 1-5 Likert scale by two cardiologists, and contrast was quantified as the mean absolute difference (MAD) in pixel intensities between two tissues, with different methods compared using Kruskal-Wallis with Bonferroni post hoc tests. Per-patient and per-segment scar detection rates were evaluated using conventional LGE images as reference. Image quality scores were highest for synthetic PSIR (4.0) and reference images (3.8), followed by synthetic tissue-optimized (3.3), gray-blood T2 -PSIR (3.0), and black-blood T2 -PSIR (2.6). Among synthetic images, PSIR yielded the highest myocardium/scar contrast (MAD = 0.42) but the lowest blood/scar contrast (MAD = 0.05), and vice versa for T2 -PSIR, while tissue-optimized images achieved a balance among all tissues (myocardium/scar MAD = 0.16, blood/scar MAD = 0.26, myocardium/blood MAD = 0.10). Based on reference mid-ventricular LGE scans, 13/15 patients had myocardial scar. The per-patient sensitivity/accuracy for synthetic images were the following: PSIR, 85/87%; black-blood T2 -PSIR, 62/53%; gray-blood T2 -PSIR, 100/93%; tissue optimized, 100/93%. Synthetic multi-contrast LGE images can be generated from post-contrast MRF data without additional scan time, with initial feasibility shown in ischemic cardiomyopathy patients.

Deep Learning for Discrimination of Hypertrophic Cardiomyopathy and Hypertensive Heart Disease on MRI Native T1 Maps.

Native T1 and radiomics were used for hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HHD) differentiation previously. The current problem is that global native T1 remains modest discrimination performance and radiomics requires feature extraction beforehand. Deep learning (DL) is a promising technique in differential diagnosis. However, its feasibility for discriminating HCM and HHD has not been investigated. To examine the feasibility of DL in differentiating HCM and HHD based on T1 images and compare its diagnostic performance with other methods. Retrospective. 128 HCM patients (men, 75; age, 50 years ± 16) and 59 HHD patients (men, 40; age, 45 years ± 17). 3.0T; Balanced steady-state free precession, phase-sensitive inversion recovery (PSIR) and multislice native T1 mapping. Compare HCM and HHD patients baseline data. Myocardial T1 values were extracted from native T1 images. Radiomics was implemented through feature extraction and Extra Trees Classifier. The DL network is ResNet32. Different input including myocardial ring (DL-myo), myocardial ring bounding box (DL-box) and the surrounding tissue without myocardial ring (DL-nomyo) were tested. We evaluate diagnostic performance through AUC of ROC curve. Accuracy, sensitivity, specificity, ROC, and AUC were calculated. Independent t test, Mann-Whitney U-test and Chi-square test were adopted for HCM and HHD comparison. P < 0.05 was considered statistically significant. DL-myo, DL-box, and DL-nomyo models showed an AUC (95% confidential interval) of 0.830 (0.702-0.959), 0.766 (0.617-0.915), 0.795 (0.654-0.936) in the testing set. AUC of native T1 and radiomics were 0.545 (0.352-0.738) and 0.800 (0.655-0.944) in the testing set. The DL method based on T1 mapping seems capable of discriminating HCM and HHD. Considering diagnostic performance, the DL network outperformed the native T1 method. Compared with radiomics, DL won an advantage for its high specificity and automated working mode. 4 TECHNICAL EFFICACY STAGE: 2.

A deep learning algorithm for noise reduction in a novel respiratory-triggered single-shot phase sensitive inversion recovery myocardial delayed enhancement cardiac MRI pulse sequence

Abstract Funding Acknowledgements Type of funding sources: None. Background Phase-sensitive inversion recovery improves tissue contrast by correcting for imperfect choice of inversion recovery time, however it is challenging to combine with a free-breathing acquisition. Deep learning (DL) algorithms have growing applications in cardiac MRI to improve image quality during image reconstruction. Purpose Here, we introduce a single-shot phase-sensitive myocardial delayed enhancement sequence with respiratory triggering (SShPSMDE-RT) (Figure 1). This novel sequence allows faster free-breathing acquisition of late gadolinium enhancement (LGE) images with reduced motion artifact (Figure 2.a). We combined this with a DL noise reduction algorithm to further improve image quality as compared to a standard segmented breath-hold (BH) PSMDE sequence. Methods 61 subjects (29 male, age 51±15) underwent cardiac MRI with the SShPSMDE-RT sequence and a standard BH sequence. The DL algorithm was applied at increasing levels (DL25, DL50, DL75, DL100) (Figure 2.b). Qualitative metrics were image quality, artifact severity, and diagnostic confidence, graded on a 5-point Likert scale. Quantitative metrics were sharpness of the left ventricle septum border and the LGE region (distance in mm for signal intensity to drop from 80% to 20%), blood-myocardium contrast-to-noise ratio (CNR), LGE-myocardium CNR, LGE signal-to-noise ratio (SNR), and LGE burden. 324 slices were included in the analysis. The sequences were compared via paired T-test. Results 27 subjects had positive LGE as determined by CMR experts. The average time to acquire a slice for SShPSMDE-RT is 4–7 seconds versus ∼30–40 seconds for the BH scan. The single-shot sequence had significantly better image quality (SShPSMDE-RT 2.1±0.8 vs. BH 1.5±0.6, p&amp;lt;0.001), less artifact (1.2±0.5 vs. 2.6±1.1, p&amp;lt;0.001), and better diagnostic confidence (3.4±0.7 vs. 2.6±0.8, p&amp;lt;0.001). Septum sharpness was slightly worse in SShPSMDE-RT images (4.1±1.7 mm vs. 3.8±1.6 mm, p = 0.008), but the DL algorithm improved sharpness of SShPSMDE-RT images such that there was no significant difference compared to BH images (p&amp;gt;0.5). There was no significant difference in LGE sharpness between the sequences. The SShPSMDE-RT images had superior blood-myocardium CNR (17.2±6.9 vs. 16.4±6.0, p = 0.040), LGE-myocardium CNR (12.1±7.2 vs. 10.4±6.6, p = 0.054), and LGE SNR (59.8±26.8 vs. 31.2±24.1, p&amp;lt;0.001); these metrics all improved with application of the DL algorithm. There was no significant difference in measured LGE burden (p = 0.12). Conclusions Our novel SShPSMDE-RT sequence significantly reduces scan time and motion artifact. This free-breathing sequence combined with a DL noise reduction algorithm provides better or similar image quality on both qualitative and quantitative metrics as compared to a standard BH PSMDE sequence. This technique can be used to obtain LGE imaging in patients who are unable to breath-hold or tolerate longer scan times.

Myocardial edema at CMR imaging end evolution of ventricular function following COVID-19 myocarditis - insights from the CARDIOCOV study

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): The CARDIOCOV project - Prototype for personalized assessment of cardiovascular risk and post-Covid myocarditis based on artificial intelligence, advanced medical imaging and cloud computing - financed by UEFISCDI PN-III-P2-2.1-PTE-2021-0450 (Contract Number 108PTE/2022). Background Myocarditis following SARS-COV-2 infection has recently become a subject of concern, being detected in a significant number of post-COVID-19 patients who undergo cardiac magnetic resonance(CMR) examination. While the role of CMR in detecting presence of viral myocarditis has been well established, the CMR features associated with significant alteration of ventricular function in post-COVID patients are not clearly identified yet. Purpose The aim of the study was to investigate the role of myocardial edema (ME) at CMR for predicting the evolution of ventricular function in patients with COVID myocarditis. Methods In total, 55 patients with CMR signs of viral myocarditis following COVID-19 infection (52.72% males, mean age 36.85+/-16.29) were enrolled in the study. The delayed gadolinium enhancement phase-sensitive inversion recovery sequences were used for characterization of the myocardial tissue, and inversion recovery images showing high signal intensity were considered suggestive of edematous changes. Patients were divided into 2 study groups, according to the presence of myocardial edema at the moment of CMR evaluation: group 1 (n=18, 32.72%) - patients without ME, and group 2 (n=37, 67.27%)-patients with ME identified by CMR. In all patients, end-distolic and end-systolic volume indexes (EDVI and ESVI), ejection fraction (EF) and stroke volume (SV) were calculated. Results Compared to patients without ME, those with ME present at CMR were older n (42.9+/-14.8 vs. 36.7+/-16.6, p = 0.145) and more frequently males(59.4% vs. 38.8%). At the same time, EF was significantly lower in patients with ME(50.9+/-14.5% in group 2 vs. 58.4+/-10.2% in group 1, p = 0.03). Patients from group 2 also exhibited a more pronounced dilatation of ventricular cavities, as reflected by a significant increase of ventricular volumes and especially of the ESVI(109.8+/-125.9 versus 80.1+/-14.2, p = 0.5 for EDVI, and 65.2+/-109.1 vs. 30.0+/-11.4, p = 0.02 for ESVI). Compared to the group without ME, those with ME presented a significantly lower stroke volume index: 44.2+/-17.3 in group 1 vs. 47.7+/-7.5, p = 0.03 in group 2. Conclusions In patients with COVID-19 myocarditis, presence of ME at CMR imaging is associated with a worse evolution of the left ventricular function, as reflected by increased ventricular dilatation and decreased cardiac output in the post-COVID period.