Cine Sequences Research Articles

Territorial Post-Revascularization Remodeling of Chronic Coronary Syndromes: Cardiac Magnetic Resonance Feature Tracking Study.

MRI feature-tracking (MRI-FT) can accurately assess ventricular myocardial deformation and regional function and may be a better predictor of mortality than ejection fraction and infarct extension. However, role of MRI-FT in assessing coronary revascularization is unclear. To assess coronary revascularization effect on territorial left ventricle (LV) function of chronic coronary syndrome (CCS) patients by MRI-FT. Prospective. 50 CCS patients (age: 62.22 ± 8.70 years) scheduled for elective percutaneous coronary intervention (PCI), and 30 healthy controls (age: 35.33 ± 11.57 years). 1.5T with balanced steady-state free precession cine sequence. Global and segmental peak systolic longitudinal, circumferential, and radial myocardial strains were quantified in both patient and healthy control groups by an experienced operator using dedicated software. Patients were studied both pre-PCI and 6-month post-PCI and LV territorial myocardial strain values were calculated by averaging the segmental values of each revascularized territory. Student's t-test, paired t-test, Mann Whitney test, and Wilcoxon signed ranks test. Significance was judged at the 5% level. Territorial longitudinal strain showed significant 6-month post-PCI improvement in the left anterior descending (LAD) and right coronary artery (RCA) territories, but there was not in the left circumflex (LCX) territory (LAD: mean - 11.41% ± 3.45% pre, -13.01% ± 3.53% post; RCA: mean - 11.11% ± 2.65% pre, -13.25% ± 2.81% post; and LCX: mean - 15.43% ± 3.97% pre, -16.17% ± 4.38% post, P = 0.215). Territorial circumferential strain showed significant post-PCI improvement in all revascularized territories (LAD: mean - 13.73% ± 6.56% pre, -16.98% ± 6.01% post; LCX: mean - 13.23% ± 4.23% pre, -16.34% ± 3.45% post; and RCA: mean - 11.24% ± 3.36% pre, -13.80% ± 3.51% post). Territorial radial strain showed no significant post-PCI improvement (LAD: mean 22.73% ± 12.38% pre, 21.79% ± 11.55% post, P = 0.541; LCX: mean 27.73% ± 7.95% pre, 29.0% ± 7.25% post, P = 0.264; and RCA: mean 36.68% ± 11.10% pre, 31.75% ± 10.95% post, P = 0.208). Territorial LV systolic function was significantly improved by coronary revascularization in CCS patients. 1 TECHNICAL EFFICACY: Stage 4.

Free-Breathing Compressed Sensing Cine Cardiac MRI for Assessment of Left Ventricular Strain by Feature Tracking in Children.

Cardiac MRI feature-tracking (FT) with breath-holding (BH) cine balanced steady state free precession (bSSFP) imaging is well established. It is unclear whether FT-strain measurements can be reliably derived from free-breathing (FB) compressed sensing (CS) bSSFP imaging. To compare left ventricular (LV) strain analysis and image quality of an FB CS bSSFP cine sequence with that of a conventional BH bSSFP sequence in children. Prospective. 40 children able to perform BHs (cohort 1 [12.1 ± 2.2 years]) and 17 children unable to perform BHs (cohort 2 [5.2 ± 1.8 years]). 3T, bSSFP sequence with and without CS. Acquisition times and image quality were assessed. LV myocardial deformation parameters were compared between BH cine and FB CS cine studies in cohort 1. Strain indices and image quality of FB CS cine studies were also assessed in cohort 2. Intraobserver and interobserver variability of strain parameters was determined. Paired t-test, Wilcoxon signed-rank test, intraclass correlation coefficient (ICC), and Bland-Altman analysis. A P-value <0.05 was considered statistically significant. In cohort 1, the mean acquisition time of the FB CS cine study was significantly lower than for conventional BH cine study (15.6 s vs. 209.4 s). No significant difference were found in global circumferential strain rate (P = 0.089), global longitudinal strain rate (P = 0.366) and EuroCMR image quality scores (P = 0.128) between BH and FB sequences in cohort 1. The overall image quality score of FB CS cine in cohort 2 was 3.5 ± 0.5 with acquisition time of 14.7 ± 2.1 s. Interobserver and intraobserver variabilities were good to excellent (ICC = 0.810 to 0.943). FB CS cine imaging may be a promising alternative technique for strain assessment in pediatric patients with poor BH ability. 1 TECHNICAL EFFICACY: Stage 1.

Utility of a 2D kinematic HASTE sequence in magnetic resonance imaging assessment of adjacent segment degeneration following anterior cervical discectomy and fusion.

To evaluate a dynamic half-Fourier acquired single turbo spin echo (HASTE) sequence following anterior cervical discectomy and fusion (ACDF) at the junctional level for adjacent segment degeneration comparing dynamic listhesis to radiographs and assessing dynamic cord contact and deformity during flexion-extension METHODS: Patients with ACDF referred for cervical spine MRI underwent a kinematic flexion-extension sagittal 2D HASTE sequence in addition to routine sequences. Images were independently reviewed by three radiologists for static/dynamic listhesis, and compared to flexion-extension radiographs. Blinded assessment of the HASTE sequence was performed for cord contact/deformity between neutral, flexion, and extension, to evaluate concordance between readers and inter-modality agreement. Inter-reader agreement for dynamic listhesis and impingement grade and inter-modality agreement for dynamic listhesis on MRI and radiographs was assessed using the kappa coefficient and percentage concordance. A total of 28 patients, mean age 60.2 years, were included. Mean HASTE acquisition time was 42 s. 14.3% demonstrated high grade dynamic stenosis (> grade 4) at the adjacent segment. There was substantial agreement for dynamic cord impingement with 70.2% concordance (kappa = 0.62). Concordance across readers for dynamic listhesis using HASTE was 81.0% (68/84) (kappa = 0.16) compared with 71.4% (60/84) (kappa = 0.40) for radiographs. Inter-modality agreement between flexion-extension radiographs and MRI assessment for dynamic listhesis across the readers was moderate (kappa = 0.41; 95% confidence interval: 0.16 to 0.67). A sagittal flexion-extension HASTE cine sequence provides substantial agreement between readers for dynamic cord deformity and moderate agreement between radiographs and MRI for dynamic listhesis. Degeneration of the adjacent segment with instability and myelopathy is one of the most common causes of pain and neurological deterioration requiring re-operation following cervical fusion surgery. • A real-time kinematic 2D sagittal HASTE flexion-extension sequence can be used to assess for dynamic listhesis, cervical cord, contact and deformity. • The additional kinematic cine sequence was well tolerated and the mean acquisition time for the 2D HASTE sequence was 42 s (range 31-44 s). • A sagittal flexion-extension HASTE cine sequence provides substantial agreement between readers for dynamic cord deformity and moderate agreement between radiographs and MRI for dynamic listhesis.

Diastology with Cardiac MRI: A Practical Guide.

Diastolic filling of the ventricle is a complex interplay of volume and pressure, contingent on active energy-dependent myocardial relaxation and myocardial stiffness. Abnormal diastolic function is the hallmark of the clinical entity of heart failure with preserved ejection fraction (HFpEF), which is now the dominant type of heart failure and is associated with significant morbidity and mortality. Although echocardiography is the current first-line imaging modality used in evaluation of diastolic function, cardiac MRI (CMR) is emerging as an important technique. The principal role of CMR is to categorize the cause of diastolic dysfunction (DD) and distinguish other entities that manifest similarly to HFpEF, particularly infiltrative and pericardial disorders. CMR also provides prognostic information and risk stratification based on late gadolinium enhancement and parametric mapping techniques. Advances in hardware, sequences, and postprocessing software now enable CMR to diagnose and grade DD accurately, a role traditionally assigned to echocardiography. Two-dimensional or four-dimensional velocity-encoded phase-contrast sequences can measure flow and velocities at the mitral inflow, mitral annulus, and pulmonary veins to provide diastolic functional metrics analogous to those at echocardiography. The commonly used cine steady-state free-precession sequence can provide clues to DD including left ventricular mass, left ventricular filling curves, and left atrial size and function. MR strain imaging provides information on myocardial mechanics that further aids in diagnosis and prognosis of diastolic function. Research sequences such as MR elastography and MR spectroscopy can help evaluate myocardial stiffness and metabolism, respectively, providing additional insights on diastolic function. The authors review the physiology of diastolic function, mechanics of diastolic heart failure, and CMR techniques in the evaluation of diastolic function. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Esophageal cancer T-staging on MRI: A preliminary study using cine and static MR sequences

ObjectivesTo evaluate the added value of cine MR in addition to static MRI for T-Staging assessment of esophageal cancer (EC). Materials and methodsThis prospective monocentric study included 54 patients (mean age 66.3 ± 9.4 years, 46 men) with histologically proven EC. They underwent MRI on a 3 T-scanner in addition to the standard workup. Acquisitions included static and cine sequences (steady-state-free-precession and real-time True-FISP during water ingestion). Three radiologists independently assessed T-staging and diagnosis confidence by reviewing (1) static sequences (S-MRI) and (2) adding cine sequences (SC-MRI). Inter-reader agreement was performed. MRI T-staging was correlated to reference standard T-staging (histopathology or consensus on endoscopic ultrasonography and imaging findings) and to clinical outcome by log-rank test. ResultsBoth S-MRI and SC-MRI T-staging showed a significant correlation with reference T-staging (rs = 0.667, P < 0.001). SC-MRI showed a slightly better performance in distinguishing T1-T3 from T4 with a sensitivity, specificity and AUC of 76.5% (95% CI: 50.1–93.2), 83.8% (68–93.8) and 0.801 (0.681–0.921) vs 70.6% (44–89.7), 83% (68–93.8) and 0.772 (0.645–0.899) for S-MRI. Compared to S-MRI, SC-MRI increased inter-reader agreement for T4a and T4b (κ = 0.403 and 0.498) and T-staging confidence. ConclusionMRI is accurate for T-staging of EC. The addition of cine sequences allows better differentiation between T1-T3 and T4 tumors with increased diagnostic confidence and inter-reader agreement.

Automated T1 and T2 mapping segmentation on cardiovascular magnetic resonance imaging using deep learning.

Structural and functional heart abnormalities can be examined non-invasively with cardiac magnetic resonance imaging (CMR). Thanks to the development of MR devices, diagnostic scans can capture more and more relevant information about possible heart diseases. T1 and T2 mapping are such novel technology, providing tissue specific information even without the administration of contrast material. Artificial intelligence solutions based on deep learning have demonstrated state-of-the-art results in many application areas, including medical imaging. More specifically, automated tools applied at cine sequences have revolutionized volumetric CMR reporting in the past five years. Applying deep learning models to T1 and T2 mapping images can similarly improve the efficiency of post-processing pipelines and consequently facilitate diagnostic processes. In this paper, we introduce a deep learning model for myocardium segmentation trained on over 7,000 raw CMR images from 262 subjects of heterogeneous disease etiology. The data were labeled by three experts. As part of the evaluation, Dice score and Hausdorff distance among experts is calculated, and the expert consensus is compared with the model's predictions. Our deep learning method achieves 86% mean Dice score, while contours provided by three experts on the same data show 90% mean Dice score. The method's accuracy is consistent across epicardial and endocardial contours, and on basal, midventricular slices, with only 5% lower results on apical slices, which are often challenging even for experts. We trained and evaluated a deep learning based segmentation model on 262 heterogeneous CMR cases. Applying deep neural networks to T1 and T2 mapping could similarly improve diagnostic practices. Using the fine details of T1 and T2 mapping images and high-quality labels, the objective of this research is to approach human segmentation accuracy with deep learning.

Lumbar intradural space reduction during the Valsalva maneuver observed using cine MRI and MR myelography: a single-case experimental study.

Previous studies have shown that the Valsalva maneuver (VM) causes spinal canal object movements. We hypothesized that this occurs because of cerebrospinal fluid (CSF) flow generated from intradural space reduction. Previous studies using myelograms reported lumbar CSF space changes during inspiration. However, no similar studies have been conducted using modern MRI. Therefore, this study analyzed intradural space reduction during the VM using cine magnetic resonance imaging (MRI). The participant was a 39-year-old, healthy, male volunteer. Cine MRI involved fast imaging employing steady-state acquisition cine sequence during three resting and VM sets for 60s each. The axial plane was at the intervertebral disc and vertebral body levels between Th12 and S1 during cine MRI. This examination was performed on 3 separate days; hence, data from nine resting and VM sets were available. Additionally, two-dimensional myelography was performed during rest and the VM. Intradural space reduction was observed during the VM using cine MRI and myelography. The intradural space cross-sectional area during the VM (mean: 129.3 mm2; standard deviation [SD]: 27.4 mm2) was significantly lower than that during the resting period (mean: 169.8; SD: 24.8; Wilcoxon signed-rank test, P < 0.001). The reduction rate of the vertebral body level (mean: 26.7%; SD: 9.4%) was larger than that of the disc level (mean: 21.4%; SD: 9.5%; Wilcoxon rank sum test, P = 0.0014). Furthermore, the reduction was mainly observed on the ventral and bilateral intervertebral foramina sides at the vertebral body and intervertebral disc levels, respectively. The intradural space was reduced during the VM, possibly because of venous dilatation. This phenomenon may be associated with CSF flow, intradural object movement, and nerve compression, potentially leading to back pain.

Total regurgitant fraction to predict aortic valve surgery in patients with concomitant aortic and mitral regurgitation

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Both aortic regurgitation (AR) and mitral regurgitation (MR) produce left ventricular (LV) volume overload (1). Current prognostic assessment of AR does not include the presence and magnitude of MR. Therefore, in patients with concomitant AR and MR we might be underestimating the future need of valve replacement surgery. Cardiac magnetic resonance (CMR) is a very precise tool to quantify LV volumes together with aortic and mitral regurgitant volumes. Combining data from cine and phase contrast sequences it is possible to obtain a set parameter: total regurgitant fraction (TRF). Purpose To describe the prognostic value of TRF in patients with concomitant AR and MR. Methods Patients with concomitant AR and MR with CMR studies were retrospectively recruited in three tertiary hospitals. Cases of at least moderate AR and any grade of MR were included in the analysis. Patients with indication of aortic valve surgery (symptoms, severe LV dilatation or reduced LV eyection fraction) in the moment of the CMR were excluded. Aortic regurgitant fraction (ARF) was calculated from the phase constrast data as the ratio of AR volume and LV forward volume. Mitral regurgitant Fraction (MRF) was calculated from the cine sequences as the ratio of the MR volume and the LV stroke volume (LVSV) . TRF was calculated as the ratio of mitral plus aortic regurgitant volumes and the LVSV (MRV+ARV/LVSV) Results 35 cases were analyzed, with a mean follow up period of 40 months. 9 patients developed indications of aortic valve surgery. TRF had an area under curve (AUC) to predict aortic valve surgery of 0.82, in opposite to aortic regurgitant fraction (ARF) which had an AUC of 0.75 (Figure 1) The optimum cutoff value of TRF and ARF to predict the need of surgery in our series were 38% and 27%, respectively. After 3 years of follow up 53% of patients with TRF &amp;gt; 38% had to be intervened (Figure 2A). In contrast, 32% of patients with ARF &amp;gt;27% had to be intervened (Figure 2B) Conclusion MR presence increases volume overload in patients with moderate or severe AR. TRF is a promising parameter to predict the need of aortic valve surgery in this patients

Impact of vein of Marshall ethanol infusion on left atrial function: an MRI study

Abstract Funding Acknowledgements Type of funding sources: None. Background Previous data suggested that left atrial (LA) function may be impaired by extensive atrial fibrillation (AF) ablation. Ethanol infusion of Vein of Marshall (EI-VOM) as an adjunctive therapy to pulmonary vein isolation is an emerging therapeutic strategy that has shown to improve efficacy in persistent AF ablation procedures and mitral isthmus line. The impact of EI-VOM scar formation on LA function has not been addressed. Purpose To analyse the effect of EI-VOM on LA function, evaluated by magnetic resonance imaging (MRI) strain parameters. Methods Twelve patients referred for de novo persistent AF or any repeat procedure were included. MRI was performed previous (baseline) and 3-month after AF ablation. MRI images were analyzed off-line with specialized post-processing software. LA volumes, LA strain parameters, including LA global longitudinal strain (GLS), LA reservoir (LASr), conduit (LAScd) and contractile (LASct) strain; LA ejection fraction (LAEF), LA passive emptying function (LAPEF) and LA active emptying function (LAAEF) were measured from SSFPs two-chamber cine sequences. Results Two patients were excluded due to absence of VOM and failed ethanolization. Ten patients (83%) underwent both MRI studies (64 [55-71]years; 80% men; de novo ablation of persistent AF (50%)). Six patients received additional mitral isthmus line and three posterior wall isolation. Mean baseline indexed LA volume was 62.7ml/m2 [47-73]. Baseline LA strain and EF parameters were: LA GLS 17.16±15.3, LASr 17.80±14.9%, LAScd -5.96±3.7%, LASct -10.35±9.5%; LAPEF 5.89±9.8, LAAEF 23.87±17.0 and LAEF 27.6±18.3%. At 3-months follow-up, no AF recurrences were detected. No differences were found regarding LA volume (57.6ml/m2 [42-64], p=0.671), strain parameters (LA GLS Δ0.62, p=0.903; LASr Δ0.02, p=0.991; LAScd Δ-0.84, p=0.563; LASct Δ0.54, p= 0.874) and LAEF parameters (LAPEF Δ4.82, p=0.592; LAAEF Δ3.03, p=0.903; and LAEF Δ7.0, p=0.213). Conclusions EI-VOM appears as a safe adjunctive strategy in AF ablation in terms of LA function. The present study did not show impairment in the main MRI strain parameters.

Glycemic Status and Myocardial Strain by Cardiac MRI in Patients With ST-Segment Elevation Myocardial Infarction.

It is uncertain how various degree of glycemic status affect left ventricular (LV) myocardial strain in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PPCI). To investigate the relationship of glycemic status and myocardial strain in STEMI patients. Prospective cohort study. 282 STEMI patients with cardiac magnetic resonance imaging 5 ± 2 days post-PPCI. Patients were divided into three groups based on the level of glycated hemoglobin A1c (HbA1c) (group 1: HbA1c < 5.7%; group 2: 5.7% ≤ HbA1c < 6.5%; group 3: HbA1c ≥ 6.5%). 3.0-T; late gadolinium enhancement, balanced steady-state free precession cine sequence, black blood fat-suppressed T2-weighted. LV function, myocardial strain, and infarct characteristics (infarct size, microvascular obstruction, and intramyocardial hemorrhage) were compared among the three groups by one-way analysis of variance (ANOVA) or Wilcoxon rank sum test. Intraobserver and interobserver reproducibility of LV myocardial strain was evaluated. ANOVA or Wilcoxon rank sum test, Pearson chi-square or Fisher's exact test, Spearman's correlation analyses and multivariable linear regression analysis. A two-tailed P value <0.05 was considered statistically significant. Infarct characteristics were similar among the three groups (P = 0.934, P = 0.097, P = 0.533, respectively). Patients with HbA1c ≥ 6.5% had decreased LV myocardial strain compared with HbA1c 5.7%-6.4%, as evidenced by global radial (GRS), global circumferential (GCS), and global longitudinal (GLS) strain. However, no significant differences in myocardial strain were observed between patients with HbA1c 5.7%-6.4% and HbA1c < 5.7% (P = 0.716; P = 0.294; P = 0.883, respectively). After adjustment for confounders, HbA1c as a continuous variable (beta coefficient [β] = -0.676; β = 0.172; β = 0.205, respectively) and HbA1c ≥ 6.5% (β = -3.682; β = 0.552; β = 0.681, respectively) were both independently associated with decreased GRS, GCS, and GLS. Patients with uncontrolled blood glucose (categorized in group HbA1c ≥ 6.5%) had worse myocardial strain. The level of HbA1c appeared to be independently associated with decreased myocardial strain in STEMI patients. 2 TECHNICAL EFFICACY STAGE: 2.

P398 ACUTE PERICARDITIS COMPLICATED BY RAPID DEVELOPMENT OF CONSTRICTION: A CASE REPORT

Abstract A 57–years–old man with no previous cardiovascular history presented with fever, hypotension, dyspnoea at rest and chest pain. The electrocardiogram showed sinus tachycardia, PR–segment depression and diffuse concave–upwards ST–segment elevation. Elevated C–reactive protein and low pro–BNP level were found at lab tests, procalcitonin and troponin were negative. Chest X–ray showed bilateral pleural effusion. Transthoracic echocardiogram (TTE) revealed mild–to–moderate serofibrinous pericardial effusion with initial diastolic collapse of right chambers, suggesting cardiac pre–tamponade. Because of the exiguity of liquid component, pericardiocentesis was not performed, patient was stabilized by fluid–challenge with hypertonic solution. Ibuprofen and colchicine were started. Left thoracentesis was performed removing one liter of fluid overall compatible with transudate. Cytological and microbiological examinations were negative. Despite of initial clinical improvement, the patient showed kidney failure and worsening of lung failure; perianal abscess was detected causing sepsis and requiring surgical drainage and antibiotic therapy with vancomycin and piperacillin/tazobactam. Culture exams were negative. After ibuprofen replacement with indomethacin a repeated TTE showed reduced pericardial effusion, but also respiratory variation in ventricular filling with signs of interventricular dependence. Cardiac magnetic resonance showed thickening and high signal intensity of pericardial layers on T2 weighted imaging and ventricular septal shift on free–breathing cine sequences, suggesting effusive–constrictive pericarditis. Left and right cardiac catheterization demonstrated ventricular “dip and plateau” pattern and ventricular discordance. Considering the lack of clinical improvement on medical therapy, off–bypass pericardiectomy was performed. Incomplete adhesion between the two pericardial layers and thick gelatinous material were found. After surgery patient experienced rapid clinical improvement; cardiac index increased from 1.5 to 3.5 L/min/m2. Effusive–constrictive pericarditis is a rare and dreaded complication of acute pericarditis. Surgery, when appropriated, is crucial for prognosis. In our case initial response to anti–inflammatory therapy with reduced pericardial effusion unmasked constrictive physiology in an effusive–constrictive pericarditis. Clinical management was complicated by sepsis which could have played a role in constriction developing.

Cardiac magnetic resonance-feature tracking technique can assess cardiac function and prognosis in patients with myocardial amyloidosis

To quantitatively assess cardiac functions in patients with cardiac amyloidosis (CA) and hypertrophic cardiomyopathy (HCM) using cardiac magnetic resonance-feature tracking (CMR-FT) technique and evaluate the prognostic value of CMR-FT in patients with CA. We retrospectively collected the data from 31 CA patients with systemic amyloidosis confirmed by Congo red staining and serum immunohistochemistry after extracardiac tissue biopsy undergoing CMR at our hospital from March, 2013 to June, 2021.Thirty-one age and gender matched patients with asymmetric left ventricular wall hypertrophy and 31 healthy individuals without organic or functional heart disease served as the controls.Radial, circumferential and longitudinal strains and strain rates of the left ventricle at the global level and in each myocardial segment (basal, middle and apical) were obtained with CMR-FT technique and compared among the 3 groups.The predictive value of myocardial strains and strain rates for all-cause mortality in CA patients was analyzed using a stepwise COX regression model. The left ventricular volume, myocardial mass, ejection fraction and cardiac output differed significantly among the groups (P < 0.05).Except for apical longitudinal strain, the global and segmental strains were all significantly lower in CA group than in HCM group (P < 0.05).The global and segmental strains were all significantly lower in CA group than in the healthy individuals (P < 0.05).The basal strain rates in the 3 directions were significantly lower in CA group than in the healthy individuals (P < 0.05), but the difference in apical strain rates was not statistically significant between the two groups.Multivariate stepwise COX analysis showed that troponin T (HR=1.05, 95%CI: 1.01-1.10, P=0.017) and middle peak diastolic circumferential strain rate (HR=6.87, 95%CI: 1.52-31.06, P=0.012) were strong predictors of death in CA patients. Strain and strain rate parameters derived from CMR-FT based on cine sequences are new noninvasive imaging markers for assessing cardiac impairment in CA and cardiac function changes in HCM, and provide independent predictive information for all-cause mortality in CA patients.

Compressed sensing cine imaging with higher temporal resolution for analysis of left atrial strain and strain rate by cardiac magnetic resonance feature tracking.

Cardiac magnetic resonance (CMR) feature tracking (FT) is more widely used in the measurement of left atrial (LA) strain and strain rate (SR). However, in recent years, researchers have attempted to improve the low temporal resolution of CMR-FT to better capture the subtle deformations of the myocardium. The technique of compressed sensing (CS) has been applied clinically, reducing scan time while increasing temporal resolution. The purpose of this study was to explore the effect of the increased temporal resolution of CS cine sequences on the analysis of LA longitudinal strain and SR. Twenty-nine healthy subjects were included in the study. They underwent CMR with a reference steady-state free precession cine sequence of conventional temporal resolution (standard SSFP sequence), a cine sequence of higher temporal resolution (HT sequence), and an HT cine sequence with CS (CS HT sequence) (temporal resolution: 22.1-44.3/24.9-47.1ms, 11.1-19.4ms, and 8.3-19.4ms, respectively). The standard SSFP sequence, HT sequence, and CS HT sequence were acquired in all subjects during the same scanning session. LA longitudinal strain and SR, reflecting LA reservoir, conduit, and contraction booster-pump function, were measured by CMR-FT and compared among the three sequences. The measurements of LASR reservoir, conduit, and booster-pump were significantly higher on the HT and CS HT sequences than on the standard SSFP sequence. The standard SSFP sequence was correlated significantly with the HT and CS HT sequences in terms of LA strain and SR analysis, respectively. The LA strain and SR measurements also showed excellent agreement between the HT and CS HT sequences. Higher temporal resolution led to significantly higher measured LASR values in CMR-FT. Furthermore, the addition of CS reduced scan time and did not affect LA longitudinal strain or SR analysis.

Cardiac MRI-Based Assessment of Myocardial Injury in Asymptomatic People Living With Human Immunodeficiency Virus: Correlation With nadir CD4 Count.

There are known cardiac manifestations of HIV, but the findings in asymptomatic subjects are still not fully explored. To evaluate for the presence of subclinical myocardial injury in asymptomatic people living with human immunodeficiency virus (PLWH) by cardiac MRI and to explore the possible association between subclinical myocardial injury and HIV-related clinical characteristics. Cross-sectional. A total of 80 asymptomatic PLWH (age: 53 years [47-56 years]; 90% male) and 50 age- and sex-matched healthy participants. A 3-T, cine sequence, T1, T2, and T2* mapping. Function analysis was derived from short axis, two-, three-, and four-chamber cine images by feature tracking. Regions of interest were manually selected in the midventricular septum T1, T2, and T2* mapping sequences. PLWH were evaluated for T1 increment (△T1 mapping = native T1 - cutoff values) and HIV-related clinical characteristics, particularly the nadir CD4 count. And PLWH were stratified into two groups according to the cutoff value of native T1: elevated native T1 and normal. T test, Wilcoxon rank-sum test, Chi-square test, Spearman rank correlation, and logistic regression. P <0.05 indicated statistical significance. Asymptomatic PLWH revealed significantly higher native myocardial T1 values (1241 ± 29 msec vs. 1189 ± 21 msec), T2 values (40.7 ± 1.5 msec vs. 37.9 ± 1.4 msec), and lower LVGRS (30.2% ± 6.2% vs. 35.8% ± 6.4%), LVGCS (-18.0% ± 2.5% vs. -19.5% ± 2.0%), and LVGLS (-16.0% ± 3.8% vs. -17.9% ± 2.6%) but showed no difference in T2* values (17.3 msec [16.3-19.1 msec] vs. 18.3 msec [16.5-19.3 msec], P = 0.201). A negative correlation between the native T1 increment in PLWH with subclinical myocardial injury and the nadir CD4 count (u = -0.316). Nadir CD4 count <500 cells/mm3 was associated with higher odds of elevated native T1 myocardial values (odds ratio, 6.12 [95% CI, 1.07-34.91]) in PLWH. Subclinical myocardial inflammation and dysfunction were present in asymptomatic PLWH, and a lower nadir CD4 count may be a risk factor for subclinical myocardial injury. 1. Stage 2.

Different methods, different results? Threshold-based versus conventional contouring techniques in clinical practice

BackgroundThe quantitative differences of left and right ventricular (LV, RV) parameters of using different cardiac MRI (CMR) post-processing techniques and their clinical impact are less studied. We aimed to assess the differences and their clinical impact between the conventional contouring (CC) and the threshold-based (TB) methods using 70% and 50% thresholds in different hypertrabeculated conditions. MethodsThis retrospective study included 30 dilated cardiomyopathy, 30 left ventricular non-compaction (LVNC), 30 arrhythmogenic cardiomyopathy patients, 30 healthy athletes and 30 healthy volunteers. All participants underwent CMR imaging on 1.5 T. Cine sequences were used to derive measures of the cardiac volumes, function, total muscle mass (TMi) and trabeculae and papillary muscle mass (TPMi) using CC and TB segmentation methods. ResultsComparing the CC and the 70% and 50% threshold TB methods, the LV and RV volumes were significantly lower, the ejection fraction (EF) and the TMi were significantly higher with the TB methods. Between the two threshold setups, only TPMi was significantly higher with the 70% threshold. Regarding the clinical benefits, the LVNC was the only group in whom all the diagnostic and therapeutic decisions and risk stratification were influenced using the TB method. Diagnostic changes occurred in three-quarters of the population, and all the cardiomyopathy groups were affected regarding the decision-making about pharmaco- and device therapy. ConclusionsUsing the TB method, only TPMi was significantly higher with the 70% threshold than the 50% setup, and both of them differed significantly from the CC technique, with relevant clinical impacts in all patient groups.

Magnetic resonance imaging reference values for cardiac morphology, function and tissue composition in adolescents.

Cardiovascular magnetic resonance (CMR) is a precise tool for the assessment of cardiac anatomy, function, and tissue composition. However, studies providing CMR reference values in adolescence are scarce. We aim to provide sex-specific CMR reference values for biventricular and atrial dimensions and function and myocardial relaxation times in this population. Adolescents aged 15-18 years with no known cardiovascular disease underwent a non-contrast 3-T CMR scan between March 2021 and October 2021. The imaging protocol included a cine steady-state free-precession sequence for the analysis of chamber size and function, as well as T2-GraSE and native MOLLI T1-mapping for the characterization of myocardial tissue. CMR scans were performed in 123 adolescents (mean age 16±0.5 years, 52% girls). Mean left and right ventricular end-diastolic indexed volumes were higher in boys than in girls (91.7±11.6 vs 78.1±8.3ml/m2, p<0.001; and 101.3±14.1 vs 84.1±10.5ml/m2, p<0.001), as was the indexed left ventricular mass (48.5±9.6 vs 36.6±6.0g/m2, p<0.001). Left ventricular ejection fraction showed no significant difference by sex (62.2±4.1 vs 62.8±4.2%, p=0.412), whereas right ventricular ejection fraction trended slightly lower in boys (55.4±4.7 vs. 56.8±4.4%, p=0.085). Indexed atrial size and function parameters did not differ significantly between sexes. Global myocardial native T1 relaxation time was lower in boys than in girls (1215±23 vs 1252±28ms, p<0.001), whereas global myocardial T2 relaxation time did not differ by sex (44.4±2.0 vs 44.1±2.4ms, p=0.384). Sex-stratified comprehensive percentile tables are provided for most relevant cardiac parameters. This cross-sectional study provides overall and sex-stratified CMR reference values for cardiac dimensions and function, and myocardial tissue properties, in adolescents. This information is useful for clinical practice and may help in the differential diagnosis of cardiac diseases, such as cardiomyopathies and myocarditis, in this population. Instituto de Salud Carlos III (PI19/01704).

Automated segmentation of long and short axis DENSE cardiovascular magnetic resonance for myocardial strain analysis using spatio-temporal convolutional neural networks

BackgroundCine Displacement Encoding with Stimulated Echoes (DENSE) facilitates the quantification of myocardial deformation, by encoding tissue displacements in the cardiovascular magnetic resonance (CMR) image phase, from which myocardial strain can be estimated with high accuracy and reproducibility. Current methods for analyzing DENSE images still heavily rely on user input, making this process time-consuming and subject to inter-observer variability. The present study sought to develop a spatio-temporal deep learning model for segmentation of the left-ventricular (LV) myocardium, as spatial networks often fail due to contrast-related properties of DENSE images. Methods2D + time nnU-Net-based models have been trained to segment the LV myocardium from DENSE magnitude data in short- and long-axis images. A dataset of 360 short-axis and 124 long-axis slices was used to train the networks, from a combination of healthy subjects and patients with various conditions (hypertrophic and dilated cardiomyopathy, myocardial infarction, myocarditis). Segmentation performance was evaluated using ground-truth manual labels, and a strain analysis using conventional methods was performed to assess strain agreement with manual segmentation. Additional validation was performed using an externally acquired dataset to compare the inter- and intra-scanner reproducibility with respect to conventional methods. ResultsSpatio-temporal models gave consistent segmentation performance throughout the cine sequence, while 2D architectures often failed to segment end-diastolic frames due to the limited blood-to-myocardium contrast. Our models achieved a DICE score of 0.83 ± 0.05 and a Hausdorff distance of 4.0 ± 1.1 mm for short-axis segmentation, and 0.82 ± 0.03 and 7.9 ± 3.9 mm respectively for long-axis segmentations. Strain measurements obtained from automatically estimated myocardial contours showed good to excellent agreement with manual pipelines, and remained within the limits of inter-user variability estimated in previous studies. ConclusionSpatio-temporal deep learning shows increased robustness for the segmentation of cine DENSE images. It provides excellent agreement with manual segmentation for strain extraction. Deep learning will facilitate the analysis of DENSE data, bringing it one step closer to clinical routine.

Additional value of T1 and T2 mapping techniques for early detection of myocardial involvement in scleroderma

BackgroundWe evaluated the prevalence of myocardial involvement by native T1 and T2 mapping, the diagnostic performance of mapping in addition to conventional Lake Louise Criteria (LLC), as well as correlations between mapping findings and clinical or conventional cardiovascular magnetic resonance (CMR) parameters in systemic sclerosis (SSc) patients. MethodsFifty-five SSc patients (52.31 ± 13.24 years, 81.8% female) and 55 age- and sex-matched healthy subjects underwent clinical, bio-humoral assessment, and CMR. The imaging protocol included: T2-weighted, early post-contrast cine sequences, native T1 and T2 mapping by a segmental approach, and late gadolinium enhancement (LGE) technique. ResultsGlobal myocardial T1 and T2 values were significantly higher in SSc patients than in healthy subjects. An increase in native T1 and/or T2 was present in the 62.1% of patients with normal conventional CMR techniques (negative LGE and T2-weighted images). Respectively, 13.5% and 59.6% of patients fulfilled original and updated LLC (overall agreement = 53.9%).Compared with patients with normal native T1, patients with increased T1 (40.0%) featured significantly higher left ventricular end-diastolic volume index and cardiac index, biventricular stroke volume indexes, and global heart T2 values, and more frequently had a history of digital ulcers. Biochemical and functional CMR parameters were comparable between patients with normal and increased T2 (61.8%). ConclusionT1 and T2 mapping are sensitive parameters that should be included in the routine clinical assessment of SSc patients for detecting early/subclinical myocardial involvement.

Ameliorative Effects of Cang-ai Volatile Oil on Left Ventricular Remodeling in Rats

To evaluate with 7T cardiac magnetic resonance tissue tracking imaging (CMR-TT) the ameliorative effect of Cang-ai volatile oil (CAVO) on left ventricular remodeling (LVR) in rats induced by isoproterenol (ISO), and to make preliminary investigation into CAVO's effects on endothelial dysfunction in LVR. A total of 35 healthy male Sprague-Dawley (SD) rats were randomly assigned to two groups, the experimental group ( n=27) and the normal control group ( n=8). The rat model of LVR was established by subcutaneous injection of ISO solution at 10 mg·kg -1·d -1 at multiple sites for 10 consecutive days. After modeling was completed, the surviving rats ( n=24) in the experimental group were then randomly assigned to the blank experimental group, CAVO group, and Shexiang Baoxin pill (SXBXP) group ( n=8 in each group). Rats in each group were given via gavage the corresponding intervention medicine or an equivalent amount of normal saline solution for 28 consecutive days. At the end of modeling and intragastric intervention, 7T CMR cine sequence scanning was conducted to collect data. Then, post-processing software CVI42 was used to analyze the images and to compare and contrast the changes in the parameters of left ventricular cardiac function and myocardial strain in each group before and after the administration of the medication. The rats were sacrificed after MRI scanning, and their hearts were harvested for pathological examination. The levels of serum biochemical indicators were measured by enzyme-linked immunosorbent assay (ELISA). CAVO significantly increased LV ejection fraction and overall myocardial strain parameters in LVR rats, while it decreased LV volume, mass, and serum levels of endothelial function indicators in LVR rats. In addition, pathological staining showed marked improvements in the hypertrophy, necrosis and interstitial fibrosis of cardiomyocytes. Through the regulation of myocardial vascular endothelial function, CAVO can significantly improve cardiac functions in LVR rats, delay the process of ventricular remodeling, and have a certain amount of protective effect on cardiac structure and function in rats.

Myocardial Contractility Pattern Characterization in Radiation-Induced Cardiotoxicity Using Magnetic Resonance Imaging: A Pilot Study with ContractiX.

Radiation therapy (RT) plays an integral role in treating thoracic cancers, despite the risk of radiation-induced cardiotoxicity. We hypothesize that our newly developed magnetic resonance imaging (MRI)-based contractility index (ContractiX) is a sensitive marker for early detection of RT-induced cardiotoxicity in a preclinical rat model of thoracic cancer RT. Adult salt-sensitive rats received image-guided heart RT and were imaged with MRI at 8 weeks and 10 weeks post-RT or sham. The MRI exam included cine and tagging sequences to measure left-ventricular ejection fraction (LVEF), mass, myocardial strain, and ContractiX. Furthermore, ventricular torsion, diastolic strain rate, and mechanical dyssynchrony were measured. Statistical analyses were performed between the sham, 8 weeks post-RT, and 10 weeks post-RT MRI parameters. The results showed that both LVEF and myocardial mass increased post-RT. Peak systolic strain and ContractiX significantly decreased post-RT, with a more relative reduction in ContractiX compared to strain. ContractiX showed an inverse nonlinear relationship with LVEF and continuously decreased with time post-RT. While early diastolic strain rate and mechanical dyssynchrony significantly changed post-RT, ventricular torsion changes were not significant post-RT. In conclusion, ContractiX measured via non-contrast MRI is a sensitive early marker for the detection of subclinical cardiac dysfunction post-RT, and it is superior to other MRI cardiac measures.