Effects of a 24-hr-shift-related short-term sleep deprivation on cardiac function: A cardiac magnetic resonance-based study.

Fatigue and sleep deprivation are common phenomena, especially among medical professionals and shift workers. Studies have proven that short episodes of sleep deprivation can lead to sympathetic hyperactivity with an elevation in blood pressure, heart rate, and an increased secretion of stress hormones (e.g. cortisol, noradrenaline, thyroid hormones). In this study investigating cardiac strain in 20 healthy subjects undergoing short-term sleep deprivation, it could be shown for the first time that 24-hr-shift-related short-term sleep deprivation leads to a significant increase in cardiac contractility, blood pressure, heart rate and stress hormone secretion. These findings may help better understand how workload and shift duration affect public health, and lay the foundation for further investigations.

Lung cancer screening with MRI: Evaluation of MRI for lung cancer screening by comparison of LDCT- and MRI-derived Lung-RADS categories in the first two screening rounds.

PURPOSE: To evaluate MRI for lung cancer screening comparing LDCT- and MRI-derived Lung-RADS categories in the first two screening rounds. MATERIALS AND METHODS: 224 participants in a lung cancer screening study were examined with MRI and low-dose CT (LDCT). Acquired MRI sequences were T2, balanced, T1 and DWI. MRI was prospectively analysed regarding nodules. Minimum nodule size was 4 mm. Nodules were assigned a Lung-RADS score based on appearance and size at baseline and after 3, 6 and 12 months. MRI findings were correlated with LDCT. RESULTS: The early recall rate dropped from 13.8% at baseline to 1.9% in the second screening round with biopsy rates of 3.6% in the first round and 0.5% in the second round. Histology revealed lung cancer in 8/9 participants undergoing biopsy/surgery. All eight cancers were accurately depicted by MRI. The following categories were assigned on MRI (results of LDCT in parentheses): 4B/4X in 10 (10) cases, 4A in 16 (15) cases, 3 in 13 (12) cases, 2 in 77 (92) cases and 1 in 140 (126) cases. Lung-RADS scoring correlated significantly between MRI and CT. The score was overestimated by MRI in one case for category 4A, in two cases for category 3 and in five cases for category 2. MRI-based Lung-RADS score was underestimated for category 1 in 20 cases. CONCLUSION: Lung-RADS might be applied for lung cancer screening with MRI, since findings correlated with LDCT. Relevant findings with a Lung-RADS score of 3 and higher were never missed or underestimated by MRI KEY POINTS: • MRI performed comparably to low-dose CT in a lung cancer-screening programme. • Lung-RADS might be applied for lung cancer screening with MRI. • Lung-RADS findings score of 3 and higher were never missed by MRI.

Safety and Feasibility of Magnetic Resonance Imaging of the Brain at 1.5 Tesla in Patients with Temporary Transmyocardial Pacing Leads.

BACKGROUND: Temporary transmyocardial pacing leads (TTPLs) represent an absolute contraindication to magnetic resonance imaging (MRI). The purpose of this study was to evaluate the safety and feasibility of MRI at 1.5 Tesla (T) using a transmit/receive (T/R) head coil in patients with TTPL. METHODS: TTPLs (220 cm, Osypka TME, Dr. Osypka GmbH, Rheinfelden, Germany) were implanted in a phantom and exposed to conditions of a 1.5 T brain examination using a T/R head coil. Temperature changes at the lead tip were continuously recorded. A total of 28 patients with TTPL and an urgent indication for a brain MRI underwent MRI at 1.5 T with vital sign monitoring. A T/R head coil was used to minimize radiofrequency exposure of the TTPL. Before and immediately after the MRI scan, TTPL lead impedance, pacing capture threshold (PCT), signal slope, and sensing were measured. Serum troponin I was determined before and after MRI to detect thermal myocardial injury. RESULTS: In vitro, the maximum temperature increase from radiofrequency-induced heating of the TTPL tip was < 1°C. In vivo, no complications, such as heating sensations, dizziness, unexpected changes in heart rate or rhythm, or other unusual signs or symptoms were observed. No significant changes in the lead impedance, PCT, signal slope, or sensing were recorded. There were no increases of serum troponin I after the MRI examination. CONCLUSIONS: MRI of the brain may be performed safely at 1.5 T using a T/R head coil in case of an urgent clinical need in patients with TTPL and may be considered a feasible and safe procedure when appropriate precautionary measures are taken.

Lung cancer screening with MRI: characterization of nodules with different non-enhanced MRI sequences.

BACKGROUND: There is increased interest in pulmonary magnetic resonance imaging (MRI) as a radiation-free alternative to computed tomography (CT) for lung cancer screening. PURPOSE: To analyze MRI characteristics of pulmonary nodules with different non-enhanced sequences. MATERIAL AND METHODS: Eighty-two participants of a lung cancer screening were included. MRI datasets of 32 individuals with 46 different nodules ≥ 6 mm were prospectively evaluated together with 50 controls by two readers. Acquired sequences were T2- short tau inversion recovery (STIR), T2, balanced steady-state free precession (bSSFP), 3D-T1, and diffusion-weighted imaging (DWI). Each sequence was randomly and separately viewed blinded to low-dose CT (LDCT). Size, shape, and contrast of nodules were evaluated on each sequence and then correlated with LDCT and histopathology. RESULTS: All eight carcinomas were detected by T2-STIR, T2, and bSSFP, and 7/8 by 3D-T1. Contrast was significantly higher for malignant nodules on all sequences. The highest contrast ratio between malignant and benign nodules was provided by T2-STIR. Of eight carcinomas, seven showed restricted diffusion. Size measurement correlated significantly between MRI and LDCT. Sensitivity/specificity for nodules ≥ 6 mm was 85-89%/92-94% for T2-STIR, 80-87%/93-96% for T2, 65-70%/96-98% for bSSFP, and 63-67%/96-100% for 3D-T1. Seven of eight subsolid nodules were visible on T2-sequences with significantly lower lesion contrast compared to solid nodules. Two of eight subsolid nodules were detected by bSFFP, none by 3D-T1. All three calcified nodules were detected by 3D-T1, one by bSSFP, and none by T2-sequences. CONCLUSION: Malignant as well as calcified and subsolid nodules seem to have distinctive characteristics on different MRI sequences. T2-imaging was most suitable for the detection of nodules ≥ 6 mm.

Flip angle optimization for balanced SSFP: Cardiac cine imaging following the application of standard extracellular contrast agent (gadobutrol).

PURPOSE: To investigate the effect of the flip angle (FA) on the blood-myocardium contrast and to define the FA leading to highest image quality in contrast-enhanced balanced steady-state free precession (bSSFP) images. bSSFP images provide excellent contrast between myocardium and blood with high signal-to-noise and contrast-to-noise ratios (SNR, CNR). In clinical practice, bSSFP images are typically acquired following the injection of extracellular contrast agents (ECAs), although ECAs decrease the blood-myocardium contrast. MATERIALS AND METHODS: First, a theoretical optimization was performed to determine the FA that maximizes CNR in bSSFP imaging 2-20 minutes after application of ECA. Second signal-ratios, contrast, SNR, and CNR were assessed in vivo in 25 patients in bSSFP images at 1.5T acquired before (FA = 50°) and 10-15 minutes after (FAs = 50°, 80°, 90°, 100°) application of a double-dose contrast agent. Image quality was assessed by two readers. RESULTS: Simulations yielded FAs in the range of 85-100° for optimal CNR in contrast-enhanced images. In vivo comparison of conventionally acquired cine images (FA 50°) showed an increase in CNR between blood and myocardium by 57% in diastole and 78% in systole in adapted contrast-enhanced bSSFP images (FA 100°). Contrast-enhanced images with an FA of 100° were rated highest in image quality assessment. CONCLUSION: By means of FA adaptation a similar blood-myocardium contrast can be achieved in contrast-enhanced bSSFP as in unenhanced bSSFP imaging with an increase in CNR. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:255-261.

Cardiac magnetic resonance based evaluation of aortic stiffness and epicardial fat volume in patients with hypertension, diabetes mellitus, and myocardial infarction.

Background Aortic stiffness and epicardial fat relate to cardiovascular risk. Their relationship with each other and their role with hypertension, diabetes mellitus (DM), and myocardial infarction (MI) can be evaluated by cardiac magnetic resonance (CMR). Purpose To explore an association between aortic stiffness and epicardial as well as paracardial fat volume (EFV and ParaFV, respectively) in hypertensive patients and to relate the results to the presence of DM and MI. Material and Methods A total of 156 hypertensive and 20 non-hypertensive participants were examined at 1.5 Tesla. A 2D-velocity-encoded sequence was acquired to assess aortic pulse wave velocity (PWV in m/s) as a measure of aortic stiffness. A 3D-Dixon sequence was used to determine EFV and ParaFV. Results PWV correlated with EFV (R = 0.474; P < 0.001), but not with ParaFV. Fat volumes (in mL/m2) and PWV were lower in non-hypertensive controls compared to hypertensive patients. EFV and PWV were significantly higher in diabetic hypertensive patients without MI (n = 19; PWV: 10.4 ± 2.9; EFV: 92.5 ± 19.3) compared to hypertension-only patients (n = 84 [no DM or MI]; EFV: 64.8 ± 25.1, PWV: 9.0 ± 2.6; P < 0.05). Logistic regression analysis showed a significant association between the presence of a MI and a higher EFV ( P < 0.05), but not with PWV ( P = 0.060) or ParaFV ( P = 0.375). Conclusion A relationship between aortic stiffness and EFV was found in hypertensive patients. Both were increased in the presence of DM; however, only EFV was increased in the presence of MI. This may relate to the PWV lowering effect of the antihypertensive medication used by hypertensive patients and underscores the benefit of EFV assessment in this regard.

Feature-tracking myocardial strain analysis in acute myocarditis: diagnostic value and association with myocardial oedema.

OBJECTIVES: To investigate the diagnostic value of cardiac magnetic resonance (CMR) feature-tracking (FT) myocardial strain analysis in patients with suspected acute myocarditis and its association with myocardial oedema. METHODS: Forty-eight patients with suspected acute myocarditis and 35 control subjects underwent CMR. FT CMR analysis of systolic longitudinal (LS), circumferential (CS) and radial strain (RS) was performed. Additionally, the protocol allowed for the assessment of T1 and T2 relaxation times. RESULTS: When compared with healthy controls, myocarditis patients demonstrated reduced LS, CS and RS values (LS: -19.5 ± 4.4% vs. -23.6 ± 3.1%, CS: -23.0 ± 5.8% vs. -27.4 ± 3.4%, RS: 28.9 ± 8.5% vs. 32.4 ± 7.4%; P < 0.05, respectively). LS (T1: r = 0.462, P < 0.001; T2: r = 0.436, P < 0.001) and CS (T1: r = 0.429, P < 0.001; T2: r = 0.467, P < 0.001) showed the strongest correlations with T1 and T2 relaxations times. Area under the curve of LS (0.79) was higher compared with those of CS (0.75; P = 0.478) and RS (0.62; P = 0.008). CONCLUSIONS: FT CMR myocardial strain analysis might serve as a new tool for assessment of myocardial dysfunction in the diagnostic work-up of patients suspected of having acute myocarditis. Especially, LS and CS show a sufficient diagnostic performance and were most closely correlated with CMR parameters of myocardial oedema. KEY POINTS: • Myocardial strain measures are considerably reduced in patients with suspected myocarditis. • Myocardial strain measures can sufficiently discriminate between diseased and healthy patients. • Myocardial strain measures show basic associations with the extent of myocardial oedema/inflammation.

The effects of extracellular contrast agent (Gadobutrol) on the precision and reproducibility of cardiovascular magnetic resonance feature tracking.

BACKGROUND: Today feature tracking (FT) is considered to be a robust assessment tool in cardiovascular magnetic resonance (CMR) for strain assessment. The FT algorithm is dependent on a high contrast between blood pool and myocardium. Extracellular contrast agents decrease blood-myocardial contrast in SSFP images and thus might affect FT results. However, in a routine CMR scan, SSFP-cine images including short axis views are partly acquired after contrast agent injection. The aim of this study was to investigate the effect of extracellular contrast agent (Gadobutrol) (CA) on the precision and reproducibility of the feature tracking algorithm. METHODS: A total of 40 patient volunteers (mean age 51.2 ± 19 years; mean LVEF 61 ± 9 %) were scanned in supine position on a clinical 1.5 T MR scanner (Philips Ingenia). SSFP-cine images in midventricular short axis view (SA) as well as horizontal long axis view (HLA) were acquired before and 10-15 min after injection of a double dose Gadobutrol. FT derived systolic circumferential and longitudinal strain parameters were then calculated for pre- and post-contrast images. RESULTS: FT derived midventricular peak systolic circumferential strain (PSCS) (-24.8 ± 6.4 % vs. -20.4 ± 6.3 %), apical PSCS (-28.67 ± 6.5 % vs. -24.06 ± 8.5 %), basal PSCS (-24.42 % ± 6.5 vs. -20.68 ± 7.1 %), peak systolic longitudinal strain (-19.57 ± 3.3 % vs. -17.24 ± 4.1 %), midventricular epicardial PSCS (-9.84 ± 3.4 % vs. -8.13 ± 3.4 %) , midventricular PSCS-rate (-1.52 ± 0.4 vs. -1.28 ± 0.5) and peak diastolic circumferential strain rate (1.4 ± 0.5 vs. 1.05 ± 0.5) were significantly reduced after CA application. Post CA strain assessment showed higher intra- and interobserver variability. Pre-CA: intraobserver: mean 0.21, Limits of agreement (LoA) -2.8 and 3.2; interobserver: mean 0.64, LoA -2.8 and 4.1. Post-CA: intraobserver: mean -0.11, LoA -5.1 to 4.9; interobserver: mean 4.93 LoA 2.4 to 12.2. CONCLUSION: The FT algorithm is dependent on a high contrast between blood and myocardium. Post CA strain results are significantly lower and less reproducible than pre-CA strain results.

Gradient Spin Echo (GraSE) imaging for fast myocardial T2 mapping.

BACKGROUND: Quantitative Cardiovascular Magnetic Resonance (CMR) techniques have gained high interest in CMR research. Myocardial T2 mapping is thought to be helpful in diagnosis of acute myocardial conditions associated with myocardial edema. In this study we aimed to establish a technique for myocardial T2 mapping based on gradient-spin-echo (GraSE) imaging. METHODS: The local ethics committee approved this prospective study. Written informed consent was obtained from all subjects prior to CMR. A modified GraSE sequence allowing for myocardial T2 mapping in a single breath-hold per slice using ECG-triggered acquisition of a black blood multi-echo series was developed at 1.5 Tesla. Myocardial T2 relaxation time (T2-RT) was determined by maximum likelihood estimation from magnitude phased-array multi-echo data. Four GraSE sequence variants with varying number of acquired echoes and resolution were evaluated in-vitro and in 20 healthy volunteers. Inter-study reproducibility was assessed in a subset of five volunteers. The sequence with the best overall performance was further evaluated by assessment of intra- and inter-observer agreement in all volunteers, and then implemented into the clinical CMR protocol of five patients with acute myocardial injury (myocarditis, takotsubo cardiomyopathy and myocardial infarction). RESULTS: In-vitro studies revealed the need for well defined sequence settings to obtain accurate T2-RT measurements with GraSE. An optimized 6-echo GraSE sequence yielded an excellent agreement with the gold standard Carr-Purcell-Meiboom-Gill sequence. Global myocardial T2 relaxation times in healthy volunteers was 52.2 ± 2.0 ms (mean ± standard deviation). Mean difference between repeated examinations (n = 5) was -0.02 ms with 95% limits of agreement (LoA) of [-4.7; 4.7] ms. Intra-reader and inter-reader agreement was excellent with mean differences of -0.1 ms, 95% LoA = [-1.3; 1.2] ms and 0.1 ms, 95% LoA = [-1.5; 1.6] ms, respectively (n = 20). In patients with acute myocardial injury global myocardial T2-RTs were prolonged (mean: 61.3 ± 6.7 ms). CONCLUSION: Using an optimized GraSE sequence CMR allows for robust, reliable, fast myocardial T2 mapping and quantitative tissue characterization. Clinically, the GraSE-based T2-mapping has the potential to complement qualitative CMR in patients with acute myocardial injuries.

Acute myocarditis: multiparametric cardiac MR imaging.

PURPOSE: To evaluate the diagnostic value of cardiac magnetic resonance (MR) imaging at 3 T in patients suspected of having acute myocarditis by using a multiparametric cardiac MR imaging approach including T1 relaxation time as an additional tool for tissue characterization. MATERIALS AND METHODS: Ethics commission approval was obtained for this prospective study, and written informed consent was obtained from all subjects. Twenty four patients with acute myocarditis (mean age ± standard deviation, 34.7 years ± 15.1; 75% men) and 42 control subjects (mean age, 38.7 years ± 10.2; 64% men) were included. Cardiac MR imaging approaches included relative T2 short tau inversion-recovery signal intensity ratio (T2 ratio), early gadolinium enhancement ratio, late gadolinium enhancement, native T1 relaxation times, and extracellular volume fraction. Receiver operating characteristic analysis was performed to compare diagnostic performance. The reference standard was the clinical evidence for acute myocarditis. RESULTS: Native T1 relaxation times were significantly longer in patients with acute myocarditis than in control subjects (1185.3 msec ± 49.3 vs 1089.1 msec ± 44.9, respectively; P < .001). Areas under the curve of native T1 relaxation times (0.94) were higher compared with those of other cardiac MR parameters (late gadolinium enhancement, 0.90; T2 ratio, 0.79; extracellular volume fraction, 0.71; early gadolinium enhancement ratio, 0.63; P = .390, .018, .002, and < .001, respectively). Sensitivity (92%), specificity (91%), and diagnostic accuracy (91%) for native T1 relaxation times (cutoff, 1140 msec) were equivalent compared with those of the established combined Lake Louise criteria (sensitivity, 92%; specificity, 80%; diagnostic accuracy, 85%). CONCLUSION: Diagnostic performance with native T1 mapping was superior to that with T2 ratio and early gadolinium enhancement ratio, and specificity was higher with native T1 mapping than that with Lake Louise criteria. This study underlines the potential of native T1 relaxation times to complement current cardiac MR approaches in patients suspected of having acute myocarditis.

CMR based measurement of aortic stiffness, epicardial fat, left ventricular myocardial strain and fibrosis in hypertensive patients.

INTRODUCTION: A combined assessment of different parameters of cardiovascular (CV) risk and prognosis can be supportive and performed with cardiac magnetic resonance (CMR). Aortic stiffness, epicardial fat volume (EFV), left ventricular (LV) strain and fibrosis were evaluated within a single CMR examination and results were related to the presence of hypertension (HTN) and diabetes mellitus (DM). METHODS: 20 healthy controls (57.2 ± 8.2 years(y); 26.2 ± 3.9 kg/m2), 31 hypertensive patients without DM (59.6 ± 6.7 y; 28.4 ± 4.7 kg/m2) and 12 hypertensive patients with DM (58.8 ± 9.9y; 30.7 ± 6.3 kg/m2) were examined at 1.5Tesla. Aortic stiffness was evaluated by calculation of aortic pulse wave velocity (PWV), EFV by a 3D-Dixon sequence. Longitudinal & circumferential systolic myocardial strain (LS; CS) were analyzed and T1-relaxation times (T1) were determined to detect myocardial fibrosis. RESULTS: EFV was highest in hypertensive patients with diabetes (78.4 ± 28.0 ml/m2) followed by only hypertensive patients (64.2 ± 27.3 ml/m2) and lowest in controls (50.3 ± 22.7 ml/m2; p < 0.05). PWV was higher in hypertensive patients with diabetes (9.8 ± 3.3 m/s) compared to only hypertensive patients (8.6 ± 1.7 m/s; p < 0.05) and to controls (8.1 ± 1.9 m/s; p < 0.05). LS&CS were worse in hypertensive patients with diabetes (LS:-20.9 ± 5.1% and CS: -24.4 ± 5.7%) compared to both only hypertensive patients (LS: -24.7 ± 4.6%; CS: -27.1 ± 5.0%; p < 0.05) and to controls (LS: -25.5 ± 3.8; CS: -28.3 ± 4.1%; p < 0.05). Both hypertensive groups with and without DM had higher T1́s (994.0 ± 43.2 ms; 991.6 ± 35.5 ms) than controls (964.6 ± 40.3 ms; p < 0.05). CONCLUSION: CMR revealed increased aortic stiffness and EFV in hypertensive patients, which were even higher in the presence of DM. Also signs of LV myocardial fibrosis and a reduced strain were revealed. These parameters support the assessment of CV risk and prognosis. They can accurately be measured with CMR within a single examination when normally different techniques are needed.

Quantitative and Qualitative Assessment of Pulmonary Emphysema with T2-Weighted PROPELLER MRI in a High-Risk Population Compared to Low-Dose CT.

PURPOSE: To determine the suitability of T2-weighted PROPELLER MRI for the assessment of pulmonary emphysema. MATERIALS AND METHODS: 60 participants in a lung cancer screening program (30 subjects with pulmonary emphysema, and 30 control subjects without emphysema) were included for this retrospective study. All subjects were examined with low-dose CT (LDCT) and MRI within the screening program. The use of a T2-weighted PROPELLER sequence for the assessment of emphysema was analyzed and correlated with the results of LDCT. The presence and the extent of pulmonary emphysema were first assessed qualitatively using a three-point score, and then quantitatively with a semi-automated software program to obtain emphysema indices. RESULTS: All 30 cases with pulmonary emphysema were accurately detected by MRI. There were 3 cases with emphysema according to MRI without emphysematous changes on LDCT (false-positive results). The qualitative scores as well as the emphysema indices were significantly higher in the emphysema group compared to the control group for MRI and LDCT (p < 0.001). Both the scores and the indices correlated significantly between MRI and LDCT (qualitative score of severity: r = 0.912/p < 0.001 in the emphysema group and r = 0.668/p < 0.001 in the control group; emphysema index: r = 0.960/p < 0.001 in the emphysema group and r = 0.746/p < 0.001 in the control group). CONCLUSION: The presence and the extent of pulmonary emphysema may be assessed qualitatively and quantitatively by T2-weighted PROPELLER MRI with very good correlation to LDCT. KEY POINTS: · T2-weighted PROPELLER MRI may be suitable for the assessment of pulmonary emphysema.. · There was significant correlation between MRI and LDCT regarding qualitative scores and quantitative emphysema indices in our study with correlation coefficients for different subgroups ranging from r = 0.668 to r = 0.960.. · T2-weighted PROPELLER MRI may have the potential to be used for follow-up examinations in patients with severe emphysema to avoid radiation exposure of repeated CTs.. CITATION FORMAT: · Meier-Schroers M, Sprinkart AM, Becker M et al. Quantitative and Qualitative Assessment of Pulmonary Emphysema with T2-Weighted PROPELLER MRI in a High-Risk Population Compared to Low-Dose CT. Fortschr Röntgenstr 2018; 190: 733 - 739.

Lung cancer screening with MRI: results of the first screening round.

PURPOSE: To evaluate the suitability of MRI for lung cancer screening in a high-risk population. MATERIALS AND METHODS: A 5-year lung cancer screening program comparing MRI and low-dose CT (LDCT) in a high-risk population was initiated. 224 subjects were examined with MRI and LDCT. Acquired MRI sequences were T2w MultiVane XD, balanced steady-state-free precession, 3D T1w GRE, and DWI with a maximum in-room-time of 20 min. Categorization and management of nodules were based on Lung-RADS. MRI findings were correlated with LDCT as a reference. Here, we report on the first screening round. RESULTS: MRI accurately detected 61 of 88 nodules 4-5 mm, 20 of 21 nodules 6-7 mm, 12 of 12 nodules 8-14 mm, 4 of 4 nodules ≥ 15 mm (solid nodules), and 8 of 11 subsolid nodules. Sensitivity/specificity of MRI for nodule detection was 69.3/96.4% for 4-5 mm, 95.2/99.6% for 6-7 mm, 100/99.6% for 8-14 mm, 100/100% for ≥ 15 mm (solid nodules), and 72.7/99.2% for subsolid nodules. The early recall rate was 13.8% for MRI and 12.5% for LDCT. Following Lung-RADS recommendations and based on interdisciplinary consensus, histology was obtained in eight subjects. The biopsy rate was 3.6% for MRI and 3.4% for LDCT. In all of these eight cases, the nodules were carcinomas, and all of them were accurately detected by MRI. CONCLUSION: The results of the first screening round suggest that MRI is suitable for lung cancer screening with an excellent sensitivity and specificity for nodules ≥ 6 mm.

Influence of observer experience on cardiac magnetic resonance strain measurements using feature tracking and conventional tagging.

AIM: CMR quantitative myocardial strain analysis is increasingly being utilized in clinical routine. CMR feature tracking (FT) is now considered an alternative to the reference standard for strain assessment -CMR tagging. The impact of observer experience on the validity of FT results has not yet been investigated. The aim of this study was therefore to evaluate the observer experience-dependency of CMR FT and to compare results with the reference standard. METHODS: CSPAMM and SSFP-Cine sequences were acquired in 38 individuals (19 patients with HFpEF,19 controls) in identical midventricular short-axis locations. Global peak systolic circumferential strain (PSCS) together with LV ejection fraction (EF) and volumes were assessed by three observers (5,3 and 0 years of CMR-strain experience). Intermodality, intra- as well inter-observer variability were assessed. RESULTS: Correlation between tagging and FT derived PSCS depended on observer experience (r = 0.69, r = 0.58 and r = 0.53). For the inexperienced observer tagging and FT derived PSCS differed significantly (p = 0.0061). Intra-observer reproducibility of tagging derived PSCS were similar for all observers (coefficient of variation (CV): 6%, 6.8% and 4.9%) while reproducibility of FT derived PSCS (CV: 7.4%, 9.4% and 15.8%) varied depending on observer experience. Inter-observer reproducibility of tagging derived PSCS for observer 1 and 2 as well as 1 and 3 for tagging (CV: 6.17%, 9.18%) was superior in comparison to FT (CV: 11.8%, 16.4%). CONCLUSIONS: Reliability and accuracy of FT based strain analysis, more than tagging based strain analysis, is dependent on reader experience. CMR strain experience or dedicated training in strain evaluation is necessary for FT to deliver accurate strain data, comparable to that of CMR tagging.

Diagnostic Value of Cardiac Magnetic Resonance Strain Analysis for Detection of Cardiac Sarcoidosis.

PURPOSE: The aim of this study was to investigate the diagnostic value of cardiac magnetic resonance (CMR)-derived strain parameters in patients with sarcoidosis, and to compare results to standard CMR markers of sarcoidosis (edema/T2 ratio, early gadolinium enhancement, late gadolinium enhancement) for prediction of disease outcome. MATERIALS AND METHODS: 61 patients with biopsy-proven sarcoidosis underwent CMR examination. According to CMR results, patients were divided into two different groups: patients with (CMR+; n = 23) and without (CMR-; n = 38) findings consistent with cardiac sarcoidosis. In addition, a group of healthy age-matched volunteers (controls; n = 22) served as controls. Left ventricular functional parameters as well as left ventricular longitudinal and circumferential strain were evaluated in all three groups. RESULTS: Compared to controls, global longitudinal strain (GLS) was significantly impaired in patients with sarcoidosis, irrespective of cardiac involvement. No significant differences in GLS could be revealed between CMR+ and CMR- patients. Circumferential strain parameters were significantly impaired in CMR+ patients in comparison to CMR- patients and controls, while no significant differences could be revealed between CMR- patients and controls. GLS was significantly lower in patients with a negative outcome compared to controls. Compared to the rest of the CMR+ and CMR- patients, the GLS in patients with a negative outcome was further reduced but did not reach statistical significance. CONCLUSION: GLS is the only strain parameter detecting left ventricular functional impairment in sarcoidosis patients with otherwise unsuspicious CMR and controls. GLS is further reduced in patients with a negative outcome. Thus, GLS may have the potential to serve as a marker for early cardiac involvement in sarcoidosis. KEY POINTS: · GLS is significantly impaired in sarcoidosis patients with an otherwise inconspicuous CMR, compared to controls. · GLS is reduced in patients with a negative outcome. · GLS may serve as a marker for early cardiac involvement in sarcoidosis. CITATION FORMAT: · Dabir D, Meyer D, Kuetting D et al. Diagnostic Value of Cardiac Magnetic Resonance Strain Analysis for Detection of Cardiac Sarcoidosis. Fortschr Röntgenstr 2018; 190: 712 - 721.

Left and right ventricular strain in the course of acute myocarditis: a cardiovascular magnetic resonance study.

PURPOSE: To investigate the degree of impairment in left (LV) and right ventricular (RV) myocardial strain parameters over the course of acute myocarditis and to evaluate its value for the prediction of functional recovery upon follow-up. MATERIALS AND METHODS: 69 patients with acute myocarditis underwent cardiac magnetic resonance imaging during the acute stage (baseline) and after a mean 92.5 ±â€Š50.4 days follow-up. Standard "Lake Louise" criteria (T2 signal intensity ratio, early gadolinium enhancement ratio and late gadolinium enhancement) and feature tracking derived LV and RV strain parameters were assessed. Logistic regression analysis was used to find predictors of functional recovery upon follow-up. RESULTS: All inflammatory parameters showed a considerable decrease over the course of the disease (P < 0.001 for all parameters). LV and RV function significantly improved on follow-up CMR (LV ejection fraction: 53.5 ±â€Š12.7 % vs. 61.3 ±â€Š9.5 %; P < 0.001, RV ejection fraction: 54.1 ±â€Š10.0 % vs. 59.4 ±â€Š6.3 %; P < 0.001). LV and RV myocardial strain (longitudinal, circumferential and radial strain) significantly improved from baseline to follow-up (P < 0.05 for all parameters). On multivariate analysis, LV global peak systolic longitudinal strain (OR: 0.303; P = 0.007) was the only independent predictor of functional recovery upon follow-up.  CONCLUSION: Alterations in LV and RV functional strain parameters occur frequently during the acute stage of myocarditis. During the course of the disease, a significant improvement in LV and RV strain parameters can be observed. It further appears that initial LV longitudinal strain may serve as a new parameter for the prediction of functional recovery upon follow-up. KEY POINTS: · Myocardial strain parameters significantly improve during the course of acute myocarditis.. · RV dysfunction can frequently be observed during the acute stage of myocarditis.. · LV longitudinal strain can independently predict functional recovery upon follow-up.. CITATION FORMAT: · Luetkens JA, Petry P, Kuetting D et al. Left and right ventricular strain in the course of acute myocarditis: a cardiovascular magnetic resonance study. Fortschr Röntgenstr 2018; 190: 722 - 732.

The effects of flip angle optimization on the precision and reproducibility of feature tracking derived strain assessment in contrast enhanced bSSFP cine images.

OBJECTIVES: The aim of this study was to investigate whether a flip angle adaptation, which is known to improve SNR and CNR in post contrast SSFP imaging, improves the precision and reproducibility of Feature Tracking (FT) derived strain assessments in post contrast bSSFP imaging. METHODS AND RESULTS: At 1.5T balanced SSFP midventricular short axis cine images were acquired with various flip angles (FA) before (FA = 50°) and 5 min after (FAs = 50°, 80°, 90°, 100°) injection of double dose Gadobutrol. FT derived systolic circumferential strain was then calculated for all pre- and post-contrast images, the intra- and inter-observer variability of strain measurements was assessed. FT derived midventricular peak systolic circumferential strain (PSCS) derived from unadapted (FA: 50°) contrast enhanced bSSFP images was significantly lower than strain derived from unenhanced bSSFP images (-16.45 ±â€¯5.1% vs -20.57 ±â€¯6.2%; p < 0.001) and showed low agreement (mean difference of -4.13 ±â€¯2.4, 95% CI:-5.3 to -3) in all 20 subjects. After adaption of the flip angle (FA: 100°), agreement between strain derived from unenhanced and adapted contrast enhanced bSSFP images (-20.57 ±â€¯6%) was strong (0.01 ±â€¯0.9, CI:-0.43 to 0.41). In comparison to intra- and interobserver variability of strain derived from unenhanced images (intra 2.9%; inter: 3.9%), strain measurements derived from adapted contrast enhanced images (FA: 100°) showed a slightly lower variability (intra: 2.5%; inter: 2.3%). CONCLUSION: If flip angle adaptation is performed, FT based strain analysis may be performed on contrast enhanced bSSFP cine images without loss of precision and accuracy.

Cardiac magnetic resonance using late gadolinium enhancement and atrial T1 mapping predicts poor outcome in patients with atrial fibrillation after catheter ablation therapy.

To determine the pre-procedural value of different fibrotic biomarkers and comprehensive cardiac magnetic resonance (CMR) for the prediction of poor response to ablation therapy in patients with atrial fibrillation (AF). Left atrial (LA) late gadolinium enhancement (LGE) and native LA T1 relaxation times were assessed using CMR. Plasma levels of relaxin, myeloperoxidase and serum levels of matrix metalloproteinase (MMP)-mediated cardiac specific titin fragmentation and MMP-mediated type IV collagen degradation were obtained. Poor outcome was defined by the recurrence of AF during 1-year follow-up. 61 patients were included in final analysis. Twenty (32.8%) patients had recurrence of AF. Patients with a recurrence of AF had a higher percentage of LA LGE (26.7 ± 12.5% vs. 17.0 ± 7.7%; P < 0.001), higher LA T1 relaxation times (856.7 ± 112.2 ms vs. 746.8 ± 91.0 ms; P < 0.001) and higher plasma levels of relaxin (0.69 ± 1.34 pg/ml vs. 0.37 ± 0.88 pg/ml; P = 0.035). In the multivariate Cox regression analysis, poor ablation outcome was best predicted by advanced LGE stage (hazard ratio (HR):5.487; P = 0.001) and T1 relaxation times (HR:1.007; P = 0.001). Pre-procedural CMR is a valuable tool for prediction of poor response to catheter ablation therapy in patients with AF. It offers various imaging techniques for outcome prediction and might be valuable for a better patient selection prior to ablation therapy.

Interrelations of Epicardial Fat Volume, Left Ventricular T1-Relaxation Times and Myocardial Strain in Hypertensive Patients: A Cardiac Magnetic Resonance Study.

PURPOSE: This cardiac magnetic resonance study was performed to assess myocardial fibrosis by evaluating T1-relaxation time (T1), to measure left ventricular (LV) strain, and to determine epicardial fat volume (EFV) in hypertensive patients with no history of cardiovascular (CV) events and to relate the results to the presence of coronary atherosclerotic artery disease (CAD) in these patients. MATERIALS AND METHODS: A total of 123 subjects were examined at 1.5 T. Of them, 98 were hypertensive patients (58 men; mean age, 62.9±10.7 y; body mass index, 29.0±5.6 kg/m) and 25 were controls without CV risk factors or disease (13 men; 60.1±10.7 y; 28.1±5.4 kg/m). All patients had a well-treated blood pressure. In the hypertensive group, 56 patients had no CAD, whereas 42 patients had CAD. T1 was assessed by a modified Look-Locker inversion recovery sequence. Longitudinal and circumferential peak systolic strain (LS; CS) was determined with dedicated cardiac magnetic resonance software (feature tracking). EFV (normalized to the body surface area) was assessed by a 3D Dixon sequence. RESULTS: T1 (ms) and EFV (mL/m) were higher and CS and LS (%) were lower in hypertensive patients compared with those in nonhypertensive controls (P<0.05), independent of the presence of CAD (controls: T1=967.2±16.9, LS=-25.2±4.6, CS=-28.7±5.0, EFV=58.2±21.1; hypertensive patients overall: T1=991.3±45.5, LS=-21.0±4.5, CS=-25.0±5.9, EFV=71.1±25.3; hypertensive patients without CAD: T1=991.6±48.4, LS=-21.0±4.7, CS=-24.6±6.3, EFV=71.3±26.6; hypertensive patients with CAD: T1=986.7±39.2, LS=-21.1±4.3, CS=-25.5±5.4, EFV=70.9±23.6). There were no significant differences between hypertensive patients with and those without CAD and between patients grouped according to the number of vessels affected (0-vessel disease, 1-vessel disease, 2-vessel disease, or 3-vessel disease). CONCLUSIONS: Hypertension is associated with signs of myocardial fibrosis and an impaired LV contractility despite a normal LV ejection fraction, as well as with an increased EFV. However, CAD, in the absence of previous pathologies with consecutive myocardial ischemic damage, did not additionally affect these parameters.