9 research outputs found
A Long-Term Broadcast Ephemeris Model for Extended Operation of GNSS Satellites
GNSS positioning relies on orbit and clock information, which is predicted on ground and transmitted by the individual satellites as part of their broadcast navigation message. The predictions are typically refreshed at least once per day and partitioned into short-arc ephemeris data sets covering a representative validity period of 0.5-4 h. For an increased autonomy of either the space or user segment, the capability to predict a GNSS satellite orbit over extended periods of up to two weeks is studied. A tailored force model for numerical orbit propagation is proposed that offers high accuracy but can still be used in real-time environments. Aside from Earth-orientation parameters, six state vector components and three empirical solar radiation pressure parameters are employed for each satellite and adjusted to past orbits. Using the Galileo constellation with its high-grade hydrogen maser clocks as an example, global average signal-in-space range errors of less than 25 m RMS and 3D position errors of less than about 50 m are demonstrated after two week predictions in 95% of all test cases over a half-year period. The autonomous orbit prediction model thus enables adequate quality for a rapid first fix or contingency navigation in case of lacking ground segment updates
Multiparametric early detection and prediction of cardiotoxicity using myocardial strain, T1 and T2 mapping, and biochemical markers: A longitudinal cardiac resonance imaging study during 2 years of follow-up
BACKGROUND: Our goal was to evaluate the ability of cardiovascular magnetic resonance for detecting and predicting cardiac dysfunction in patients receiving cancer therapy. Left ventricular ejection fraction, global and regional strain utilizing fast-strain-encoded, T1 and T2 mapping, and cardiac biomarkers (troponin and BNP [brain natriuretic peptide]) were analyzed.
METHODS: Sixty-one patients (47 with breast cancer, 11 with non-Hodgkin lymphoma, and 3 with Hodgkin lymphoma) underwent cardiovascular magnetic resonance scans at baseline and at regular intervals during 2 years of follow-up. The percentage of all left ventricular myocardial segments with strain ≤-17% (normal myocardium [%]) was analyzed. Clinical cardiotoxicity (CTX) and sub-CTX were defined according to standard measures.
RESULTS: Nine (15%) patients developed CTX, 26 (43%) had sub-CTX. Of the 35 patients with CTX or sub-CTX, 24 (69%) were treated with cardioprotective medications and showed recovery of cardiac function. The amount of normal myocardium (%) exhibited markedly higher accuracy for the detection of CTX and sub-CTX compared with left ventricular ejection fraction, T1, and T2 mapping as well as troponin I (Δareas under the curve=0.20, 0.24, and 0.46 for normal myocardium (%) versus left ventricular ejection fraction, troponin I, and T1 mapping,
CONCLUSIONS: Normal myocardium (%) derived by fast-strain-encoded cardiovascular magnetic resonance, is an accurate and sensitive tool that can establish cardiac safety in patients with cancer undergoing cardiotoxic chemotherapy not only for the early detection but also for the prediction of those at risk of developing CTX. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03543228
Relationship between quality of life indicators and cardiac status indicators in chemotherapy patients
AIM: With the aim of improving personalized treatment of patients on chemotherapy, the objective of the study was to assess the degree of association between selected Quality of life (QoL) indicators and both clinical and imaging cardiac status indicators when detecting deterioration in QoL of these patients.
METHODS: In a cohort clinical study in Hamburg, from August 2017 through October 2020, 59 cancer patients, aged 18-80 years, were evaluated before chemotherapy, and at several follow-ups, using EQ-5D and SF-36 QoL questionnaires, fast strain-encoded (fast-SENC) cardiac magnetic resonance (CMR), conventional CMR, and echocardiography, and further received a clinical and biomarker examination. Data was analyzed using survival analyses. A decline of more than 5% in each observed QoL metric value was defined as the observed event. Patient were separated into groups according to the presentation of cardiotoxicity as per its clinical definition, the establishment of the indication for cardioprotective therapy initiation, and by a worsening in the value of each observed imaging metric by more than 5% in the previous follow-up compared to the corresponding pre-chemotherapy baseline value.
RESULTS: Among clinical cardiac status indicators, the indication for cardioprotective therapy showed statistically good association with QoL scores (EQ-5D p=0.028; SF-36 physical component p=0.016; SF-36 mental component p=0.012). In terms of imaging metrics, the MyoHealth segmental myocardial strain score was the only one demonstrating consistently good QoL score association (EQ-5D p=0.005; SF-36 physical component p=0.056; SF-36 mental component p=0.002).
CONCLUSIONS: Established fast-SENC CMR scores are capable of highlighting patients with reduced QoL, who require more frequent/optimal management
Guideline adherence in the use of coronary angiography in patients presenting at the emergency department without myocardial infarction – results from the German ENLIGHT-KHK project
Background
For patients with acute myocardial infarction (AMI), direct coronary angiography (CA) is recommended, while for non-AMI patients, the diagnostic work-up depends on clinical criteria. This analysis provides initial prospective German data for the degree of guideline-adherence (GL) in the use of CA on non-AMI patients presenting at the emergency department (ED) with suspected acute coronary syndrome (ACS) according to the 2015 ESC-ACS-GL. Furthermore the implications of the application of the 2020 ESC-ACS-GL recommendations were evaluated.
Methods
Patient symptoms were identified using a standardized questionnaire; medical history and diagnostic work-up were acquired from health records. In accordance with the 2015 ESC-ACS-GL, CA was considered GL-adherent if intermediate risk criteria (IRC) were present or non-invasive, image-guided testing (NIGT) was pathological.
Results
Between January 2019 and August 2021, 229 patients were recruited across seven centers. Patients presented with chest pain, dyspnea, and other symptoms in 66.7%, 16.2% and 17.1%, respectively, were in mean 66.3 ± 10.5 years old, and 36.3% were female. In accordance with the 2015 ESC-ACS-GL, the use of CA was GL-adherent for 64.0% of the patients. GL-adherent compared to non-adherent use of CA resulted in revascularization more often (44.5% vs. 17.1%, p < 0.001). Applying the 2020 ESC-ACS-GL, 20.4% of CA would remain GL-adherent.
Conclusions
In the majority of cases, the use of CA was adherent to the 2015 ESC-ACS-GL. With regard to the 2020 and 2023 ESC-ACS-GL, efforts to expand the utilization of NIGT are crucial, especially as GL-adherent use of CA is more likely to result in revascularization
Multi-parametric assessment of left ventricular hypertrophy using late gadolinium enhancement, T1 mapping and strain-encoded cardiovascular magnetic resonance
Aim!#!To evaluate the ability of single heartbeat fast-strain encoded (SENC) cardiovascular magnetic resonance (CMR) derived myocardial strain to discriminate between different forms of left ventricular (LV) hypertrophy (LVH).!##!Methods!#!314 patients (228 with hypertensive heart disease (HHD), 45 with hypertrophic cardiomyopathy (HCM), 41 with amyloidosis, 22 competitive athletes, and 33 healthy controls) were systematically analysed. LV ejection fraction (LVEF), LV mass index and interventricular septal (IVS) thickness, T1 mapping and atypical late gadolinium enhancement (LGE) were assessed. In addition, the percentage of LV myocardial segments with strain ≤ - 17% (%normal myocardium) was determined.!##!Results!#!Patients with amyloidosis and HCM exhibited the highest IVS thickness (17.4 ± 3.3 mm and 17.4 ± 6 mm, respectively, p &lt; 0.05 vs. all other groups), whereas patients with amyloidosis showed the highest LV mass index (95.1 ± 20.1 g/m!##!Conclusion!#!Fast-SENC derived myocardial strain is a valuable tool for differentiating between athletes vs. HCM and athletes vs. HHD. Combining strain and LGE data is useful for differentiating between HHD vs. HCM and HCM vs. cardiac amyloidosis
Left and right ventricular strain using fast strain-encoded cardiovascular magnetic resonance for the diagnostic classification of patients with chronic non-ischemic heart failure due to dilated, hypertrophic cardiomyopathy or cardiac amyloidosis
Aims!#!To compare the ability of left ventricular (LV) and right ventricular (RV) strain measured by fast-strain encoded cardiovascular magnetic resonance (CMR) (fast-SENC) with LV- and RV-ejection fraction for the diagnostic classification of patients with different stages of chronic heart failure (stages A-D based on American College of Cardiology/American Heart Association guidelines) due to non-ischemic cardiomyopathies.!##!Methods!#!Our study population consisted of 276 consecutive patients who underwent CMR for clinical reasons, and 19 healthy subjects. Wall motion score index and non-infarct related late gadolinium enhancement (LGE), LV ejection fraction (LVEF) and RV ejection fraction (RVEF) and global LV- and RV-longitudinal (GLS) and circumferential strain (GCS) based on fast-SENC acquisitions, were calculated in all subjects. The percentage of LV and RV myocardial segments with strain ≤ - 17% (%normal LV and RV myocardium) was determined in all subjects.!##!Results!#!LVEF and RVEF, LV-GLS, LV-GCS, RV-GLS, RV-GCS and %normal LV- and RV myocardium depressed with increasing heart failure stage (p &lt; 0.001 for all by ANOVA). By multivariable analysis, %normal LV and RV myocardium exhibited closer associations to heart failure stages than LVEF and RVEF (r!##!Conclusions!#!In patients with non-ischemic cardiomyopathy, %normal LV and RV myocardium, by fast-SENC, enables improved identification of asymptomatic patients with subclinical LV-dysfunction. This technique may be useful for the early identification of such presumably healthy subjects at risk for heart failure and for monitoring LV and RV deformation during pharmacologic interventions in future studies
Evaluation of the guideline-adherence of coronary angiography in patients with suspected chronic coronary syndrome – Results from the German prospective multicentre ENLIGHT-KHK project
Background: With 900′000 coronary angiographies (CA) per year, Germany has the highest annual per capita volume in Europe. Until now there are no prospective clinical data on the degree of guideline-adherence in the use of CA in patients with suspected chronic coronary syndrome (CCS) in Germany. Methods: Between January 2019 and August 2021, 458 patients with suspected CCS were recruited in nine German centres. Guideline-adherence was evaluated according to the current European Society of Cardiology and German guidelines. Pre-test probability (PTP) for CAD was determined using age, gender, and a standardized patient questionnaire to identify symptoms. Data on the diagnostic work-up were obtained from health records. Results: Patients were in mean 66.6 years old, male in 57.3 %, had known CAD in 48.4 % and presented with typical, atypical, non-anginal chest pain or dyspnoea in 35.7 %, 41.3 %, 23.0 % and 25.4 %, respectively. PTP according to the European guidelines was in mean 24.2 % (11.9 %-36.5 % 95 % CI). 20.9 % of the patients received guideline-recommended preceding non-invasive image guided testing. The use of CA was adherent to the European and German guideline recommendations in 20.4 % and 25.4 %, respectively. In multivariate-analysis, arterial hypertension and prior revascularization were predictors of guideline non-adherence. Conclusion: These are the first prospective clinical data which demonstrated an overall low degree of guideline-adherence in the use of CA in patients with suspected CCS in the German health care setting. To improve adherence rates, the availability of and access to non-invasive image guided testing needs to be strengthened. (German Clinical Trials Registry DRKS00015638 – Registration Date: 19.02.2019