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BACKGROUND: Myocardial injury is common in end-stage renal disease (ESRD) patients, but the presence and severity of myocardial injury in different left ventricular (LV) phenotypes were still not fully explored. PURPOSE: To evaluate myocardial tissue characteristics and deformation in ESRD patients on peritoneal dialysis separated into normal geometry, concentric remodeling, concentric left ventricular hypertrophy (LVH) and eccentric LVH patterns by multiparametric cardiac MRI. STUDY TYPE: Prospective. POPULATION: A total of 142 subjects, including 102 on peritoneal dialysis (69 males) and 40 healthy controls (27 males). FIELD STRENGTH/SEQUENCE: At 3.0 T, cine sequence, T1 mapping and T2 mapping. ASSESSMENT: LV mass index and LV remodeling index were used to create four subgroups with normal geometry, concentric remodeling, concentric LVH, and eccentric LVH. LV function, strain and strain rate, myocardial native T1 and T2 were measured. STATISTICAL TESTS: Descriptive statistics, analysis of variance and analysis of covariance, Pearson/Spearman correlation, stepwise regression, and intraclass correlation coefficient. P-value <0.05 was considered statistically significant. RESULTS: Even in normal geometry, LV strain parameters still diminished compared with the controls (global radial strain: 30.5 ± 7.7% vs. 37.1 ± 7.9%; global circumferential strain: -18.2 ± 2.6% vs. -20.6 ± 2.2%; global longitudinal strain: -13.3 ± 2.5% vs. -16.0 ± 2.8%). Eccentric LVH had significantly lower global circumferential systolic strain rate than concentric LVH (-0.82 ± 0.21%/- second vs. -0.96 ± 0.20%/- second). Compared with the controls, the four subgroups all revealed elevated native T1 and T2, especially in eccentric LVH, while concentric remodeling had the least changes including native T1, T2, and LV ejection fraction. After adjusting for covariates, there was no statistically significant difference in T2 between the four subgroups (P = 0.359). DATA CONCLUSIONS: Eccentric LVH is associated with the most pronounced evidence of myocardial tissue characteristics and function impairment, while as a benign remodeling, the concentric remodeling subgroup had the least increase in native T1. This study further confirms that native T1 and strain indicators can reflect the severity of myocardial injury in ESRD, providing better histological and functional basis for future grouping treatments. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 3.

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T1/T2 parametric mapping may reveal patterns of elevation ("hotspots") in myocardial diseases, such as rejection in orthotopic heart transplant (OHT) patients. This study aimed to evaluate the diagnostic accuracy of free-breathing (FB) multi-parametric SAturation recovery single-SHot Acquisition (mSASHA) T1/T2 mapping in identifying hotspots present on conventional Breath-held Modified Look-Locker Inversion recovery (BH MOLLI) T1 and T2-prepared balanced steady-state free-precession (BH T2p-bSSFP) maps in pediatric OHT patients. Pediatric OHT patients underwent noncontrast 1.5T CMR with BH MOLLI T1 and T2p-bSSFP and prototype FB mSASHA T1/T2 mapping in 8 short-axis slices. FB and BH T1/T2 hotspots were segmented using semi-automated thresholding (ITK-SNAP) and their 3D coordinate locations were collected (3-Matic, Materialise, Leuven, Belgium). Receiver operator characteristic curve analysis and measures of central tendency were utilized. 40 imaging datasets from 23 pediatric OHT patients were obtained. FB mSASHA yielded a sensitivity of 82.8% for T1 and 80% for T2 maps when compared to the standard BH MOLLI, as well as 100% specificity for both T1 and T2 maps. When identified on both FB and BH maps, hotspots overlapped in all cases, with an average long axis offset between FB and BH hotspot centers of 5.8 mm (IQR 3.5-8.2) on T1 and 5.9 mm (IQR 3.5-8.2) on T2 maps. FB mSASHA T1/T2 maps can identify hotspots present on conventional BH T1/T2 maps in pediatric patients with OHT, with high sensitivity, specificity, and overlap in 3D space. Free-breathing mapping may improve patient comfort and facilitate OHT assessment in younger patient populations.

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Raw data, simulated and acquired phantom images, and quantitative longitudinal and transverse relaxation times (T1/T2) maps from two open-source Magnetic Resonance Imaging (MRI) pulse sequences are presented in this dataset along with corresponding ".seq" files, sequence implementation scripts, and reconstruction/analysis scripts [1]. Real MRI data were collected from a 3T Siemens Prisma Fit and a 1.5T Siemens Aera via the Pulseq open-source MR sequence platform, and corresponding in silico data were generated using the simulation module of Virtual Scanner [2]. This dataset and its associated code can be used to validate the pipeline for using the same pulse sequences at other research sites using Pulseq, to provide guidelines for documenting and sharing open-source pulse sequences in general, and to demonstrate practical, customizable acquisition scripts using the PyPulseq library.

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Acute myocarditis was recently demonstrated in previously healthy young male patients after receipt of mRNA SARS-CoV-2 vaccines. Herein, we report on a 21-year-old man who presented with acute fatigue, myalgia, and chest pain 2 days after his second SARS-CoV-2 vaccination with BNT162b2. Cardiac magnetic resonance (CMR) showed acute myocarditis, with mildly impaired LV-function and abundant subepicardial late gadolinium enhancement (LGE). Control CMR after 3 months showed full functional recovery and complete disappearance of LGE. The benefits of SARS-CoV-2 vaccination may significantly exceed the very rare and, in this case, fully reversible adverse effects.

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Perimyocarditis is a well-known acute inflammation of the pericardium and the underlying myocardium. Most commonly perimyocarditis is of viral aetiology, specifically the coxsackie B virus. However, nowadays SARS-CoV-2 associated with COVID-19 infections has emerged as a potential rare cause of perimyocarditis. This case report will demonstrate a case of a young female with perimyocarditis as diagnosed by magnetic resonance imaging (MRI) accompanied by antigens indicating a past COVID-19 infection. Clinical status as well as Findings at MRI, echocardiography and lab results will be reviewed.

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Most astronauts experience back pain after spaceflight, primarily located in the lumbar region. Intervertebral disc herniations have been observed after real and simulated microgravity. Spinal deconditioning after exposure to microgravity has been described, but the underlying mechanisms are not well understood. The dry immersion (DI) model of microgravity was used with eighteen male volunteers. Half of the participants wore thigh cuffs as a potential countermeasure. The spinal changes and intervertebral disc (IVD) content changes were investigated using magnetic resonance imaging (MRI) analyses with T1-T2 mapping sequences. IVD water content was estimated by the apparent diffusion coefficient (ADC), with proteoglycan content measured using MRI T1-mapping sequences centered in the nucleus pulposus. The use of thigh cuffs had no effect on any of the spinal variables measured. There was significant spinal lengthening for all of the subjects. The ADC and IVD proteoglycan content both increased significantly with DI (7.34 ± 2.23% and 10.09 ± 1.39%, respectively; mean ± standard deviation), p < 0.05). The ADC changes suggest dynamic and rapid water diffusion inside IVDs, linked to gravitational unloading. Further investigation is needed to determine whether similar changes occur in the cervical IVDs. A better understanding of the mechanisms involved in spinal deconditioning with spaceflight would assist in the development of alternative countermeasures to prevent IVD herniation.

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OBJECTIVES: This study assessed changes in myocardial native T1 and T2 values after supine exercise stress in healthy subjects and in patients with suspected ischemia as potential imaging markers of ischemia. BACKGROUND: With emerging data on the long-term retention of gadolinium in the body and brain, there is a need for an alternative noncontrast cardiovascular magnetic resonance (CMR)-based myocardial ischemia assessment. METHODS: Twenty-eight healthy adult subjects and 14 patients with coronary artery disease (CAD) referred for exercise stress and/or rest single-photon emission computed tomography/myocardial perfusion imaging (SPECT/MPI) for evaluation of chest pain were prospectively enrolled. Free-breathing myocardial native T1 and T2 mapping were performed before and after supine bicycle exercise stress using a CMR-compatible supine ergometer positioned on the MR table. Differences in T1 rest, T2 rest and T1 post-exercise, T2 post-exercise values were calculated as T1 and T2 reactivity, respectively. RESULTS: The mean exercise intensity was 104 W, with exercise duration of 6 to 12 min. After exercise, native T1 was increased in healthy subjects (p < 0.001). T1 reactivity, but not T2 reactivity, correlated with the rate-pressure product as the index of myocardial blood flow during exercise (r = 0.62; p < 0.001). In patients with CAD, T1 reactivity was associated with the severity of myocardial perfusion abnormality on SPECT/MPI (normal: 4.9%; quartiles: 3.7% to 6.3%, mild defect: 1.2%, quartiles: 0.08% to 2.5%; moderate defect: 0.45%, quartiles: -0.35% to 1.4%; severe defect: 0.35%, quartiles: -0.44% to 0.8%) and had similar potential as SPECT/MPI to detect significant CAD (>50% diameter stenosis on coronary angiography). The area under the receiver-operating characteristic curve was 0.80 versus 0.72 (p = 0.40). The optimum cutoff value of T1 reactivity for predicting flow-limiting stenosis was 2.5%, with a sensitivity of 83% and a specificity of 92%, a negative predictive value of 96%, a positive predictive value of 71%, and an area under the curve of 0.86. CONCLUSIONS: Free-breathing stress/rest native T1 mapping, but not T2 mapping, can detect physiological changes in the myocardium during exercise. Our feasibility study in patients shows the potential of this technique as a method for detecting myocardial ischemia in patients with CAD without using a pharmacological stress agent.

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Increased native myocardial T1 times in chronic kidney disease (CKD) may be due to diffuse interstitial myocardial fibrosis (DIF) or due to interstitial edema/inflammation. Concerns relating to nephrogenic systemic fibrosis with gadolinium-based contrast agents (GBCA) limit their use in end-stage kidney disease (ESKD) to measure extracellular volume (ECV) and characterise myocardial fibrosis. This study aimed to examine stability of myocardial T1 and T2 times before, and within 2 months after kidney transplantation; a time frame when volume status normalises but myocardial remodelling is unlikely to have occurred, and to compare these with ECV using GBCA after transplantation. Twenty-four patients with ESKD underwent serial cardiovascular magnetic resonance imaging, including T1 and T2 mapping. GBCA was administered on follow-up provided eGFR was >30 ml/min/1.73 m2. Eighteen age- and sex-matched controls were studied at one timepoint. ECV (ECV 28 ±â€¯2% vs. 24 ±â€¯2%, p = 0.001) and T2 times were higher in ESKD compared to controls. After transplantation, septal T1 times increased (MOLLI 985 ms ±â€¯25 vs. 1002 ms ±â€¯30, p = 0.014; ShMOLLI 974 ms ±â€¯39 vs. 992 ms ±â€¯33, p = 0.113), LV volumes reduced (LVEDvol indexed 79 ±â€¯24 vs. 63 ±â€¯20 ml/m2, p = 0.005) but LV mass was unchanged (LV mass index 89 g/m2 ±â€¯38 to 83 g/m2 ±â€¯23, p = 0.141). T2 times did not change after transplantation. Both ECV and myocardial T1 times are elevated in ESKD, supporting the theory that elevated T1 times are due to DIF, although a contribution from myocardial edema cannot be fully excluded. The lack of any fall in T1 or T2 times after transplantation suggests that myocardial T1 times are a stable measure of DIF in CKD.

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BACKGROUND: Idiopathic inflammatory myopathy (IIM) is a group of autoimmune diseases with systemic myositis which may involve the myocardium. Cardiac involvement in IIM, although often subclinical, may mimic clinical manifestations of acute viral myocarditis (AVM). Our aim was to investigate the usefulness of the combined analysis of cardiovascular magnetic resonance (CMR) T1 and T2 mapping parameters measured both in the myocardium and in the thoracic skeletal muscles to differentiate AVM from IIM cardiac involvement. METHODS: Sixty subjects were included in this retrospective study (36 male, age 45 ± 16 years): twenty patients with AVM, twenty patients with IIM and cardiac involvement and twenty healthy controls. Study participants underwent CMR imaging with modified Look-Locker inversion-recovery (MOLLI) T1 mapping and 3-point balanced steady-state-free precession T2 mapping. Relaxation times were quantified after endocardial and epicardial delineation on basal and medial short-axis slices, as well as in different thoracic skeletal muscle groups present in the CMR field-of-view. ROC-Analysis was performed to assess the ability of mapping indices to discriminate the study groups. RESULTS: Mapping parameters in the thoracic skeletal muscles were able to discriminate between AVM and IIM patients. Best skeletal muscle parameters to identify IIM from AVM patients were reduced post-contrast T1 and increased extracellular volume (ECV), resulting in an area under the ROC curve (AUC) of 0.95 for post-contrast T1 and 0.96 for ECV. Conversely, myocardial mapping parameters did not discriminate IIM from AVM patients but increased native T1 (AUC 0.89 for AVM; 0.84 for IIM) and increased T2 (AUC 0.82 for AVM; 0.88 for IIM) could differentiate both patient groups from healthy controls. CONCLUSION: CMR myocardial mapping detects cardiac inflammation in AVM and IIM compared to normal myocardium in healthy controls but does not differentiate IIM from AVM. However, thoracic skeletal muscle mapping was able to accurately discern IIM from AVM.

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