Background: Myocardial infarction leads to complex changes in left ventricular (LV) hemodynamics. It remains unknown how four-dimensional acute changes in LV-cavity blood flow kinetic energy... Show moreBackground: Myocardial infarction leads to complex changes in left ventricular (LV) hemodynamics. It remains unknown how four-dimensional acute changes in LV-cavity blood flow kinetic energy affects LV-remodeling.Methods and results: In total, 69 revascularised ST-segment elevation myocardial infarction (STEMI) patients were enrolled. All patients underwent cardiovascular magnetic resonance (CMR) examination within 2 days of the index event and at 3-month. CMR examination included cine, late gadolinium enhancement, and whole-heart four-dimensional flow acquisitions. LV volume-function, infarct size (indexed to body surface area), microvas-cular obstruction, mitral inflow, and blood flow KEi (kinetic energy indexed to end-diastolic volume) charac-teristics were obtained. Adverse LV-remodeling was defined and categorized according to increase in LV end -diastolic volume of at least 10%, 15%, and 20%. Twenty-four patients (35%) developed at least 10%, 17 pa-tients (25%) at least 15%, 11 patients (16%) at least 20% LV-remodeling. Demographics and clinical history were comparable between patients with/without LV-remodeling. In univariable regression-analysis, A-wave KEi was associated with at least 10%, 15%, and 20% LV-remodeling (p = 0.03, p = 0.02, p = 0.02, respectively), whereas infarct size only with at least 10% LV-remodeling (p = 0.02). In multivariable regression-analysis, A-wave KEi was identified as an independent marker for at least 10%, 15%, and 20% LV-remodeling (p = 0.09, p < 0.01, p < 0.01, respectively), yet infarct size only for at least 10% LV-remodeling (p = 0.03).Conclusion: In patients with STEMI, LV hemodynamic assessment by LV blood flow kinetic energetics demon-strates a significant inverse association with adverse LV-remodeling. Late-diastolic LV blood flow kinetic ener-getics early after acute MI was independently associated with adverse LV-remodeling. Show less
Assadi, H.; Grafton-Clarke, C.; Demirkiran, A.; Geest, R.J. van der; Nijveldt, R.; Flather, M.; ... ; Garg, P. 2022
Objectives: Mitral regurgitation (MR) and microvascular obstruction (MVO) are common complications of myocardial infarction (MI). This study aimed to investigate the association between MR in ST... Show moreObjectives: Mitral regurgitation (MR) and microvascular obstruction (MVO) are common complications of myocardial infarction (MI). This study aimed to investigate the association between MR in ST-elevation MI (STEMI) subjects with MVO post-reperfusion. STEMI subjects undergoing primary percutaneous intervention were enrolled. Cardiovascular magnetic resonance (CMR) imaging was performed within 48-hours of initial presentation. 4D flow images of CMR were analysed using a retrospective valve tracking technique to quantify MR volume, and late gadolinium enhancement images of CMR to assess MVO. Results: Among 69 patients in the study cohort, 41 had MVO (59%). Patients with MVO had lower left ventricular (LV) ejection fraction (EF) (42 +/- 10% vs. 52 +/- 8%, P < 0.01), higher end-systolic volume (98 +/- 49 ml vs. 73 +/- 28 ml, P < 0.001) and larger scar volume (26 +/- 19% vs. 11 +/- 9%, P < 0.001). Extent of MVO was associated with the degree of MR quantified by 4D flow (R = 0.54, P = 0.0003). In uni-variate regression analysis, investigating the association of CMR variables to the degree of acute MR, only the extent of MVO was associated (coefficient = 0.27, P = 0.001). The area under the curve for the presence of MVO was 0.66 (P = 0.01) for MR > 2.5 ml. We conclude that in patients with reperfused STEMI, the degree of acute MR is associated with the degree of MVO. Show less
Background: Left ventricular thrombus (LVT) formation is a frequent and serious complication of myocardial infarction (MI). How global LV flow characteristics are related to this phenomenon is yet... Show moreBackground: Left ventricular thrombus (LVT) formation is a frequent and serious complication of myocardial infarction (MI). How global LV flow characteristics are related to this phenomenon is yet uncertain. In this study, we investigated LV flow differences using 4D flow cardiovascular magnetic resonance (CMR) between chronic MI patients with LVT [MI-LVT(+)] and without LVT [MI-LVT(-)], and healthy controls. Methods: In this prospective cohort study, the 4D flow CMR data were acquired in 19 chronic MI patients (MI-LVT (+), n = 9 and MI-LVT(-), n = 10) and 9 age-matched controls. All included subjects were in sinus rhythm. The following LV flow parameters were obtained: LV flow components (direct, retained, delayed, residual), mean and peak kinetic energy (KE) values (indexed to instantaneous LV volume), mean and peak vorticity values, and diastolic vortex ring properties (position, orientation, shape). Results: The MI patients demonstrated a significantly larger amount of delayed and residual flow, and a smaller amount of direct flow compared to controls (p = 0.02, p = 0.03, and p < 0.001, respectively). The MI-LVT(+) patients demonstrated numerically increased residual flow and reduced retained and direct flow in comparison to MI-LVT(-) patients. Systolic mean and peak LV blood flow KE values were significantly lower in MI patients compared to controls (p = 0.04, p = 0.03, respectively). Overall, the mean and peak LV vorticity values were significantly lower in MI patients compared to controls. The mean and peak systolic vorticity at the basal level were significantly higher in MI-LVT(+) than in MI-LVT(-) patients (p < 0.01, for both). The vortex ring core during E-wave in MI-LVT(+) group was located in a less tilted orientation to the LV compared to MI-LVT(-) group (p < 0.01). Conclusions: Chronic MI patients with LVT express a different distribution of LV flow components, irregular vorticity vector fields, and altered diastolic vortex ring geometric properties as assessed by 4D flow CMR. Larger prospective studies are warranted to further evaluate the significance of these initial observations. Show less
Background Right atrial (RA) area predicts mortality in patients with pulmonary hypertension, and is recommended by the European Society of Cardiology/European Respiratory Society pulmonary... Show moreBackground Right atrial (RA) area predicts mortality in patients with pulmonary hypertension, and is recommended by the European Society of Cardiology/European Respiratory Society pulmonary hypertension guidelines. The advent of deep learning may allow more reliable measurement of RA areas to improve clinical assessments. The aim of this study was to automate cardiovascular magnetic resonance (CMR) RA area measurements and evaluate the clinical utility by assessing repeatability, correlation with invasive haemodynamics and prognostic value. Methods A deep learning RA area CMR contouring model was trained in a multicentre cohort of 365 patients with pulmonary hypertension, left ventricular pathology and healthy subjects. Inter-study repeatability (intraclass correlation coefficient (ICC)) and agreement of contours (DICE similarity coefficient (DSC)) were assessed in a prospective cohort (n = 36). Clinical testing and mortality prediction was performed in n = 400 patients that were not used in the training nor prospective cohort, and the correlation of automatic and manual RA measurements with invasive haemodynamics assessed in n = 212/400. Radiologist quality control (QC) was performed in the ASPIRE registry, n = 3795 patients. The primary QC observer evaluated all the segmentations and recorded them as satisfactory, suboptimal or failure. A second QC observer analysed a random subcohort to assess QC agreement (n = 1018). Results All deep learning RA measurements showed higher interstudy repeatability (ICC 0.91 to 0.95) compared to manual RA measurements (1st observer ICC 0.82 to 0.88, 2nd observer ICC 0.88 to 0.91). DSC showed high agreement comparing automatic artificial intelligence and manual CMR readers. Maximal RA area mean and standard deviation (SD) DSC metric for observer 1 vs observer 2, automatic measurements vs observer 1 and automatic measurements vs observer 2 is 92.4 +/- 3.5 cm(2), 91.2 +/- 4.5 cm(2) and 93.2 +/- 3.2 cm(2), respectively. Minimal RA area mean and SD DSC metric for observer 1 vs observer 2, automatic measurements vs observer 1 and automatic measurements vs observer 2 was 89.8 +/- 3.9 cm(2), 87.0 +/- 5.8 cm(2) and 91.8 +/- 4.8 cm(2). Automatic RA area measurements all showed moderate correlation with invasive parameters (r = 0.45 to 0.66), manual (r = 0.36 to 0.57). Maximal RA area could accurately predict elevated mean RA pressure low and high-risk thresholds (area under the receiver operating characteristic curve artificial intelligence = 0.82/0.87 vs manual = 0.78/0.83), and predicted mortality similar to manual measurements, both p < 0.01. In the QC evaluation, artificial intelligence segmentations were suboptimal at 108/3795 and a low failure rate of 16/3795. In a subcohort (n = 1018), agreement by two QC observers was excellent, kappa 0.84. Conclusion Automatic artificial intelligence CMR derived RA size and function are accurate, have excellent repeatability, moderate associations with invasive haemodynamics and predict mortality. Show less
Grafton-Clarke, C.; Crandon, S.; Westenberg, J.J.M.; Swoboda, P.P.; Greenwood, J.P.; Geest, R.J. van der; ... ; Garg, P. 2021
Objectives Four-dimensional flow CMR allows for a comprehensive assessment of the blood flow kinetic energy of the ventricles of the heart. In comparison to standard two-dimensional image... Show moreObjectives Four-dimensional flow CMR allows for a comprehensive assessment of the blood flow kinetic energy of the ventricles of the heart. In comparison to standard two-dimensional image acquisition, 4D flow CMR is felt to offer superior reproducibility, which is important when repeated examinations may be required. The objective was to evaluate the inter-observer and intra-observer reproducibility of blood flow kinetic energy assessment using 4D flow of the left ventricle in 20 healthy volunteers across two centres in the United Kingdom and the Netherlands. Data description This dataset contains 4D flow CMR blood flow kinetic energy data for 20 healthy volunteers with no known cardiovascular disease. Presented is kinetic energy data for the entire cardiac cycle (global), the systolic and diastolic components, in addition to blood flow kinetic energy for both early and late diastolic filling. This data is available for reuse and would be valuable in supporting other research, such as allowing for larger sample sizes with more statistical power for further analysis of these variables. Show less
Sokolski, M.; Gajewski, P.; Zymlinski, R.; Biegus, J.; Berg, J.M. ten; Bor, W.; ... ; Ponikowski, P. 2021
PURPOSE: We evaluated whether the severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) pandemic was associated with changes in the pattern of acute cardiovascular admissions across European... Show morePURPOSE: We evaluated whether the severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) pandemic was associated with changes in the pattern of acute cardiovascular admissions across European centers.METHODS: We set-up a multicenter, multinational, pan-European observational registry in 15 centers from 12 countries. All consecutive acute admissions to emergency departments and cardiology departments throughout a 1-month period during the COVID-19 outbreak were compared with an equivalent 1-month period in 2019. The acute admissions to cardiology departments were classified into 5 major categories: acute coronary syndrome, acute heart failure, arrhythmia, pulmonary embolism, and other.RESULTS: Data from 54,331 patients were collected and analyzed. Nine centers provided data on acute admissions to emergency departments comprising 50,384 patients: 20,226 in 2020 compared with 30,158 in 2019 (incidence rate ratio [IRR] with 95% confidence interval [95%CI]: 0.66 [0.58-0.76]). The risk of death at the emergency departments was higher in 2020 compared to 2019 (odds ratio [OR] with 95% CI: 4.1 [3.0-5.8], P < 0.0001). All 15 centers provided data on acute cardiology departments admissions: 3007 patients in 2020 and 4452 in 2019; IRR (95% CI): 0.68 (0.64-0.71). In 2020, there were fewer admissions with IRR (95% CI): acute coronary syndrome: 0.68 (0.63-0.73); acute heart failure: 0.65 (0.58-0.74); arrhythmia: 0.66 (0.60-0.72); and other: 0.68(0.62-0.76). We found a relatively higher percentage of pulmonary embolism admissions in 2020: odds ratio (95% CI): 1.5 (1.1-2.1), P = 0.02. Among patients with acute coronary syndrome, there were fewer admissions with unstable angina: 0.79 (0.66-0.94); non-ST segment elevation myocardial infarction: 0.56 (0.50-0.64); and ST-segment elevation myocardial infarction: 0.78 (0.68-0.89).CONCLUSION: In the European centers during the COVID-19 outbreak, there were fewer acute cardiovascular admissions. Also, fewer patients were admitted to the emergency departments with 4 times higher death risk at the emergency departments. (C) 2020 Published by Elsevier Inc. Show less
Background The T-1 Mapping and Extracellular volume (ECV) Standardization (T1MES) program explored T-1 mapping quality assurance using a purpose-developed phantom with Food and Drug Administration ... Show moreBackground The T-1 Mapping and Extracellular volume (ECV) Standardization (T1MES) program explored T-1 mapping quality assurance using a purpose-developed phantom with Food and Drug Administration (FDA) and Conformite Europeenne (CE) regulatory clearance. We report T-1 measurement repeatability across centers describing sequence, magnet, and vendor performance. Methods Phantoms batch-manufactured in August 2015 underwent 2 years of structural imaging, B-0 and B-1, and "reference" slow T-1 testing. Temperature dependency was evaluated by the United States National Institute of Standards and Technology and by the German Physikalisch-Technische Bundesanstalt. Center-specific T-1 mapping repeatability (maximum one scan per week to minimum one per quarter year) was assessed over mean 358 (maximum 1161) days on 34 1.5 T and 22 3 T magnets using multiple T-1 mapping sequences. Image and temperature data were analyzed semi-automatically. Repeatability of serial T-1 was evaluated in terms of coefficient of variation (CoV), and linear mixed models were constructed to study the interplay of some of the known sources of T-1 variation. Results Over 2 years, phantom gel integrity remained intact (no rips/tears), B-0 and B-1 homogenous, and "reference" T-1 stable compared to baseline (% change at 1.5 T, 1.95 +/- 1.39%; 3 T, 2.22 +/- 1.44%). Per degrees Celsius, 1.5 T, T-1 (MOLLI 5s(3s)3s) increased by 11.4 ms in long native blood tubes and decreased by 1.2 ms in short post-contrast myocardium tubes. Agreement of estimated T-1 times with "reference" T-1 was similar across Siemens and Philips CMR systems at both field strengths (adjusted R-2 ranges for both field strengths, 0.99-1.00). Over 1 year, many 1.5 T and 3 T sequences/magnets were repeatable with mean CoVs < 1 and 2% respectively. Repeatability was narrower for 1.5 T over 3 T. Within T1MES repeatability for native T-1 was narrow for several sequences, for example, at 1.5 T, Siemens MOLLI 5s(3s)3s prototype number 448B (mean CoV = 0.27%) and Philips modified Look-Locker inversion recovery (MOLLI) 3s(3s)5s (CoV 0.54%), and at 3 T, Philips MOLLI 3b(3s)5b (CoV 0.33%) and Siemens shortened MOLLI (ShMOLLI) prototype 780C (CoV 0.69%). After adjusting for temperature and field strength, it was found that the T-1 mapping sequence and scanner software version (both P < 0.001 at 1.5 T and 3 T), and to a lesser extent the scanner model (P = 0.011, 1.5 T only), had the greatest influence on T-1 across multiple centers. Conclusion The T1MES CE/FDA approved phantom is a robust quality assurance device. In a multi-center setting, T-1 mapping had performance differences between field strengths, sequences, scanner software versions, and manufacturers. However, several specific combinations of field strength, sequence, and scanner are highly repeatable, and thus, have potential to provide standardized assessment of T-1 times for clinical use, although temperature correction is required for native T-1 tubes at least. Show less
Garg, P.; Geest, R.J. van der; Swoboda, P.P.; Crandon, S.; Fent, G.J.; Foley, J.R.J.; ... ; Plein, S. 2019
PurposeTo validate three widely-used acceleration methods in four-dimensional (4D) flow cardiac MR; segmented 4D-spoiled-gradient-echo (4D-SPGR), 4D-echo-planar-imaging (4D-EPI), and 4D-k-t Broad... Show morePurposeTo validate three widely-used acceleration methods in four-dimensional (4D) flow cardiac MR; segmented 4D-spoiled-gradient-echo (4D-SPGR), 4D-echo-planar-imaging (4D-EPI), and 4D-k-t Broad-use Linear Acquisition Speed-up Technique (4D-k-t BLAST).Materials and MethodsAcceleration methods were investigated in static/pulsatile phantoms and 25 volunteers on 1.5 Tesla MR systems. In phantoms, flow was quantified by 2D phase-contrast (PC), the three 4D flow methods and the time-beaker flow measurements. The later was used as the reference method. Peak velocity and flow assessment was done by means of all sequences. For peak velocity assessment 2D PC was used as the reference method. For flow assessment, consistency between mitral inflow and aortic outflow was investigated for all pulse-sequences. Visual grading of image quality/artifacts was performed on a four-point-scale (0=no artifacts; 3=nonevaluable).ResultsFor the pulsatile phantom experiments, the mean error for 2D PC=1.01.1%, 4D-SPGR=4.91.3%, 4D-EPI=7.61.3% and 4D-k-t BLAST=4.41.9%. In vivo, acquisition time was shortest for 4D-EPI (4D-EPI=8 +/- 2min versus 4D-SPGR=9 +/- 3min, P<0.05 and 4D-k-t BLAST=9 +/- 3min, P=0.29). 4D-EPI and 4D-k-t BLAST had minimal artifacts, while for 4D-SPGR, 40% of aortic valve/mitral valve (AV/MV) assessments scored 3 (nonevaluable). Peak velocity assessment using 4D-EPI demonstrated best correlation to 2D PC (AV:r=0.78, P<0.001; MV:r=0.71, P<0.001). Coefficient of variability (CV) for net forward flow (NFF) volume was least for 4D-EPI (7%) (2D PC:11%, 4D-SPGR: 29%, 4D-k-t BLAST: 30%, respectively).ConclusionIn phantom, all 4D flow techniques demonstrated mean error of less than 8%. 4D-EPI demonstrated the least susceptibility to artifacts, good image quality, modest agreement with the current reference standard for peak intra-cardiac velocities and the highest consistency of intra-cardiac flow quantifications. Level of Evidence: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:272-281. Show less
