Application of low tube potentials in CCTA results from the PROTECTION VI study

OBJECTIVES The aim of this study was to assess the use of low tube potentials for coronary computed tomography angiography (CCTA) in worldwide clinical practice and its influence on radiation exposure, contrast agent volume, and image quality.BACKGROUND CCTA is frequently used in clinical practice. Lowering of tube potential is a potent method to reduce radiation exposure and to economize contrast agent volume.METHODS CCTAs of 4,006 patients from 61 international study sites were analyzed regarding very-tow (= 130 kVp) tube potentials. The impact on dose-length product (DLP) and contrast agent volume was analyzed. Image quality was determined by evaluation of the diagnostic applicability and assessment of the objective image parameters signal-to-noise-ratio (SNR) and contrast-to-noise-ratio (CNR).RESULTS When compared with conventional tube potentials, low tube potentials were used in 56% of CCTAs (<= 80 kVp 9%; 90 to 100 kVp: 47%), which varied among sites from 0% to 100%. Tube potential reduction was associated with low-cardiovascular risk profile, low body mass index (BMI), and new-generation scanners. Median radiation exposure was lowered by 68% or 50% and median contrast agent volume by 25% or 13% for tube potential protocols of <= 80 kVp or 90 to 100 kVp when compared with conventional tube potentials, respectively (all p < 0.001). With the use of lower tube potentials, the frequency of diagnostic scans was maintained (p = 0.41), whereas SNR and CNR significantly improved (both p < 0.001). Considering BMI eligibility criteria, 58% (n = 946) of conventionally scanned patients would have been suitable for low tube potential protocols, and 44% (n = 831) of patients scanned with 90 to 100 kVp would have been eligible for very-low tube potential CCTA imaging of <= 80 kVp.CONCLUSIONS This large international registry confirms the feasibility of tube potential reduction in clinical practice leading to rower radiation exposure and lower contrast volumes. The current registry also demonstrates that this strategy is stilt underused in daily practice. (C) 2020 by the American College of Cardiology Foundation.Cardiolog

The DZHK research platform: maximisation of scientific value by enabling access to health data and biological samples collected in cardiovascular clinical studies

The German Centre for Cardiovascular Research (DZHK) is one of the German Centres for Health Research and aims to conduct early and guideline-relevant studies to develop new therapies and diagnostics that impact the lives of people with cardiovascular disease. Therefore, DZHK members designed a collaboratively organised and integrated research platform connecting all sites and partners. The overarching objectives of the research platform are the standardisation of prospective data and biological sample collections among all studies and the development of a sustainable centrally standardised storage in compliance with general legal regulations and the FAIR principles. The main elements of the DZHK infrastructure are web-based and central units for data management, LIMS, IDMS, and transfer office, embedded in a framework consisting of the DZHK Use and Access Policy, and the Ethics and Data Protection Concept. This framework is characterised by a modular design allowing a high standardisation across all studies. For studies that require even tighter criteria additional quality levels are defined. In addition, the Public Open Data strategy is an important focus of DZHK. The DZHK operates as one legal entity holding all rights of data and biological sample usage, according to the DZHK Use and Access Policy. All DZHK studies collect a basic set of data and biosamples, accompanied by specific clinical and imaging data and biobanking. The DZHK infrastructure was constructed by scientists with the focus on the needs of scientists conducting clinical studies. Through this, the DZHK enables the interdisciplinary and multiple use of data and biological samples by scientists inside and outside the DZHK. So far, 27 DZHK studies recruited well over 11,200 participants suffering from major cardiovascular disorders such as myocardial infarction or heart failure. Currently, data and samples of five DZHK studies of the DZHK Heart Bank can be applied for

Highly-parallelized simulation of a pixelated LArTPC on a GPU

The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype

Impact of diabetes on coronary artery plaque volume by coronary CT angiography and subsequent adverse cardiac events

Background: To investigate the impact of diabetes on coronary artery total plaque volume (TPV) and adverse events in long-term follow-up.Methods: One-hundred-and-eight diabetic patients were matched to 324 non-diabetic patients, with respect to age, sex, body-mass index, hypertension, smoking habits, LDL and HDL cholesterol, family history for CAD as well as aspirin and statin medication. In all patients, TPV was quantified from coronary CT angiographies (CTA) using dedicated software. All-cause mortality, acute coronary syndrome and late revascularisation ( > 90 days) served as combined endpoint.Results: Patients were followed for 5.6 years. The endpoint occurred in 18 (16.7%) diabetic and 26 (8.0%) nondiabetic patients (odds ratio 2.3, p = 0.03). Diabetic patients had significantly higher TPV than non-diabetic patients (55.1 mm 3 [IQR: 6.2 and 220.4 mm(3)] vs. 24.9 mm 3 [IQR: 0 and 166.7 mm(3)], p = 0.02). A TPV threshold of 110.5 mm(3) provided good separation of diabetic and non-diabetic patients at higher and lower risk for adverse events. Noteworthy, diabetic and non-diabetic patients with a TPV 110.5 mm(3) had significantly higher incidence of adverse events (hazard ratio 2.3, p = 0.03) compared to non-diabetic patients with TPV > 110.5 mm(3). There was incremental prognostic value in diabetic and non-diabetic patients over the Framingham Risk Score (Integrated Discrimination Improvement: 0.052 and 0.012, p for both < 0.05).Conclusion: Diabetes is associated with significantly higher TPV, which is independent of other CAD risk factors. Quantification of TPV improves the identification of diabetic patients at higher risk for future adverse events.Cardiovascular Aspects of Radiolog

Coronary plaque volume and predictors for fast plaque progression assessed by serial coronary CT angiography-A single-center observational study

Purpose: The rationale of this study was to identify patients with fast progression of coronary plaque volume PV and characterize changes in PV and plaque components over time.Method: Total PV (TPV) was measured in 350 patients undergoing serial coronary computed tomography angiography (median scan interval 3.6 years) using semi-automated software. Plaque morphology was assessed based on attenuation values and stratified into calcified, fibrous, fibrous-fatty and low-attenuation PV for volumetric measurements. Every plaque was additionally classified as either calcified, partially calcified or non-calcified.Results: In total, 812 and 955 plaques were detected in the first and second scan. Mean TPV increase was 20 % on a per-patient base (51.3 mm(3) [interquartile range (IQR): 14.4, 126.7] vs. 61.6 mm(3) [IQR: 16.7, 170.0]). TPV increase was driven by calcified PV (first scan: 7.6 mm(3) [IQR: 0.2, 33.6] vs. second scan: 16.6 mm(3) [IQR: 1.8, 62.1], p 1.3 mm(3) increase of TPV per month. Male sex (odds ratio 3.1, p = 0.02) and typical angina (odds ratio 3.95, p = 0.03) were identified as risk factors for fast TPV progression, while high-density lipoprotein cholesterol had a protective effect (odds ratio per 10 mg/dl increase of HDL cholesterol: 0.72, p 50 % stenosis at follow-up was observed in 34 of 327 (10.4 %) calcified plaques, in 13 of 401 (3.2 %) partially calcified plaques and 2 of 221 (0.9 %) non-calcified plaques (p < 0.01).Conclusion: Fast plaque progression was observed in male patients and patients with typical angina. High HDL cholesterol showed a protective effect.Cardiovascular Aspects of Radiolog

Quantified coronary total plaque volume from computed tomography angiography provides superior 10-year risk stratification

Aims Automated coronary total plaque volume (TPV) quantification derived from coronary computed tomographic angiography (CTA) datasets provide exact and reliable assessment of calcified and non-calcified coronary atheroscler- osis burden. The aim of this analysis was to investigate the long-term predictive value of TPV.Methods and results TPV was quantified in 1577 patients undergoing coronary CTA and cardiovascular events were collected during 10.5 years (interquartile range 6.0-11.4) of follow-up. The study endpoint comprised cardiac death and acute cor- onary syndrome and occurred in 59 (3.7%) patients. Coronary TPV provided additive prognostic value over clinical risk assessed with the Morise Score and coronary artery disease severity (rise in C-index from 0.744 to 0.769, P=0.03). A category-based reclassification approach combining the Morise Score and TPV revealed superior risk stratification (categorical net reclassification improvement: 0.48 with 95% CI 0.13-0.68, P< 0.001) and resulted in reclassification of 800 (51%) patients compared with the Morise Score alone. The 10-year risk for the study endpoint was 0.6% (95% CI 0-1.3) for patients classified as low risk (n = 807), 4.8% (95% CI 2.4-7.2) for patients at intermediate risk (n = 400), and 10.3% (95% CI 6.6-13.9) for patients at high risk (n = 370) using the combined reclassification approach.Conclusion Quantification of TPV from coronary CTA permits an improved 10-year cardiovascular risk stratification.Cardiovascular Aspects of Radiolog

Room for improvement in non-pharmacological systemic sclerosis care? - a cross-sectional online survey of 650 patients

Contains fulltext : 225783.pdf (publisher's version ) (Open Access)BACKGROUND/ OBJECTIVE: To gain insight in the use of current systemic sclerosis (SSc) care provided by health professionals from the patient perspective. We focused on referral reasons, treatment goals, the alignment with unmet care needs, and outcome satisfaction. METHODS: Dutch SSc patients from 13 participating rheumatology departments were invited to complete an online survey. Descriptive statistics were used to describe current use of non-pharmacological care and outcome satisfaction. Reasons for referral and treatment goals were encoded in International Classification of Function and Disability (ICF) terms. RESULTS: We included 650 patients (mean (standard deviation [SD]) age, 59.4 (11.4) years. 50% had contact with a health professional in the past year; 76.3% since disease onset. Physiotherapists were the most frequently visited in the past year (40.0%), followed by dental hygienists (11.4%) and podiatrists (9.2%). The three most common referral reasons were pain, joint mobility and cardiovascular functions. Fatigue, Raynaud's phenomenon, physical limitations, reduced hand function and joint problems were mentioned by more than 25% of all respondents as unmet needs. The proportion of patients treated in the past year by a health professional who were satisfied with knowledge and expertise of their health professionals was 74.4%; 73% reported improved daily activities and better coping with complaints. However, 48.9% perceived that the collaboration between rheumatologist and health professional was never or only sometimes sufficient. CONCLUSION: Despite the high outcome satisfaction and good accessibility of health professionals, there are obstacles in the access to non-pharmacological care and communication barriers between health professionals and rheumatologists

Contrast agent volume for coronary computed tomography angiography imaging in current clinical practice

Cardiolog

Contrast agent volume for coronary computed tomography angiography imaging in current clinical practice

Cardiolog