67 research outputs found

    Discrimination of intravascular lumen and dissections in single intravascular ultrasound images using subtraction, conventional averaging and saline flush

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    With current 30-MHz intravascular ultrasound systems, flowing blood may cause considerable backscatter which in real-time images is characterized by dynamic speckle. However, in a single intravascular ultrasound image (still-frame) the discrimination between arterial lumen and wall may be difficult due to the frozen intraluminal speckle, particularly in the presence of dissections. We compared subtraction, averaging and saline flush as methods to improve the discrimination between arterial lumen and wall in a single image. The real-time images served as gold standard. In 22 patients who underwent peripheral balloon angioplasty, ultrasound images obtained from 84 sites were examined. The sensitivity and specificity of detecting dissections were in the subtraction image 85% and 100%, in the averaged image 57% and 96%, and in the saline flush image 58% and 86%, respectively. Subtraction is a promising method to outline the irregular lumen in a single image

    Data on the impact of scan quality on the diagnostic performance of CCTA, SPECT, and PET for diagnosing myocardial ischemia defined by fractional flow reserve on a per vessel level

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    Scan quality directly impacts the diagnostic performance of non-invasive imaging modalities as reported in a substudy of the PACIFC-trial: "Impact of Scan Quality on the Diagnostic Performance of CCTA, SPECT, and PET for Diagnosing Myocardial Ischemia Defined by Fractional Flow Reserve" [1]. This Data-in-Brief paper supplements the hereinabove mentioned article by presenting the diagnostic performance of CCTA, SPECT, and PET on a per vessel level for the detection of hemodynamic significant coronary artery disease (CAD) when stratified according to scan quality and vascular territory

    Patient Perspectives on Novel Treatments in Haemophilia: A Qualitative Study

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    Background and Objective: New treatments for haemophilia are under development or entering the market, including extended half-life products, designer drugs and gene therapy, thereby increasing treatment options for haemophilia. It is currently unknown how people with haemophilia decide whether to switch to a new treatment. Therefore, the objective of this study was to explore what factors may play a role when Dutch patients and parents of boys with moderate or severe haemophilia make decisions about whether to switch to a different treatment, and how disease and treatment characteristics may affect these decisions. This may aid clinical teams in tailored information provision and shared decision making. Methods: We conducted interviews among adults with moderately severe or severe haemophilia and parents of young boys with severe haemophilia. We aimed to include participants from a variety of backgrounds in terms of involvement in the haemophilia community, age, treatment centre and treatments. Participants were recruited through the Netherlands Haemophilia Society and a haemophilia treatment centre. Semi-structured interviews were recorded and transcribed verbatim. Thematic content analysis was used to analyse the data. Results: Twelve people with haemophilia and two mothers of boys with haemophilia were included. In general, participants reported to be satisfied with their current treatment. However, they considered ease of use of the medication (fewer injections, easier handling, alternative administration) an added value of new treatments. Participants were aware of the high cost of coagulation factor products and some expressed their concern about the Netherlands Haemophilia Society’s long-term willingness to pay for current and novel treatments, especially for increased usage due to high-risk activities. Participants also expressed their concerns about the short- and long-term safety of new treatments and believed the effects of gene therapy were not yet fully understood. Participants expected their treatment team to inform them when a particular new treatment would be suitable for them. Conclusions: With the number of treatment options set to increase, it is important for healthcare providers to be aware of how patient experiences shape patients’ decisions about new therapies

    Comparison between the performance of quantitative flow ratio and perfusion imaging for diagnosing myocardial ischemia

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    OBJECTIVES This study compared the performance of the quantitative flow ratio (QFR) with single-photon emission computed tomography (SPECT) and positron emission tomography (PET) myocardial perfusion imaging (MPI) for the diagnosis of fractional flow reserve (FFR)-defined coronary artery disease (CAD).BACKGROUND QFR estimates FFR solely based on cine contrast images acquired during invasive coronary angiography (ICA). Head-to-head studies comparing QFR with noninvasive MPI are lacking.METHODS A total of 208 (624 vessels) patients underwent technetium -99m tetrofosmin SPECT and [15O]H2O PET imaging before ICA in conjunction with FFR measurements. ICA was obtained without using a dedicated QFR acquisition protocol, and QFR computation was attempted in all vessels interrogated by FFR (552 vessels).RESULTS QFR computation succeeded in 286 (52%) vessels. QFR correlated well with invasive FFR overall (R = 0.79; p < 0.001) and in the subset of vessels with an intermediate (30% to 90%) diameter stenosis (R = 0.76; p < 0.001). Overall, per-vessel analysis demonstrated QFR to exhibit a superior sensitivity (70%) in comparison with SPECT (29%; p < 0.001), whereas it was similar to PET (75%; p = 1.000). Specificity of QFR (93%) was higher than PET (79%; p < 0.001) and not different from SPECT (96%; p = 1.000). As such, the accuracy of QFR (88%) was superior to both SPECT (82%; p = 0.010) and PET (78%; p = 0.004). Lastly, the area under the receiver operating characteristics curve of QFR, in the overall sample (0.94) and among vessels with an intermediate lesion (0.90) was higher than SPECT (0.63 and 0.61; p < 0.001 for both) and PET (0.82; p < 0.001 and 0.77; p = 0.002), respectively.CONCLUSIONS In this head-to-head comparative study, QFR exhibited a higher diagnostic value for detecting FFRdefined significant CAD compared with perfusion imaging by SPECT or PET. (J Am Coll Cardiol Img 2020;13:1976-85) (c) 2020 by the American College of Cardiology Foundation.Cardiovascular Aspects of Radiolog

    Appropriate use criteria for optical coherence tomography guidance in percutaneous coronary interventions: Recommendations of the working group of interventional cardiology of the Netherlands Society of Cardiology

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    Introduction: Optical coherence tomography (OCT) enables detailed imaging of the coronary wall, lumen and intracoronary implanted devices. Responding to the lack of specific appropriate use criteria (AUC) for this technique, we conducted a literature review and a procedure for appropriate use criteria. Methods: Twenty-one of all 184 members of the Dutch Working Group on Interventional Cardiology agreed to evaluate 49 pre-specified cases. During a meeting, factual indications were established whereupon members individually rated indications on a 9-point scale, with the opportunity to substantiate their scoring. Results: Twenty-six indications were rated ‘Appropriate’, eighteen indications ‘May be appropriate’, and five ‘Rarely appropriate’. Use of OCT was unanimously considered ‘Appropriate’ in stent thrombosis, and ‘Appropriate’ for guidance in PCI, especially in distal left main coronary artery and proximal left anterior descending coronary artery, unexplained angiographic abnormalities, and use of bioresorbable vascular scaffold (BVS). OCT was considered ‘Rarely Appropriate’ on top of fractional flow reserve (FFR) for treatment indication, assessment of strut coverage, bypass anastomoses or assessment of proximal left main coronary artery. Conclusions: The use of OCT in stent thrombosis is unanimously considered ‘Appropriate’ by these experts. Varying degrees of consensus exists on the appropriate use of OCT in other settings

    Heritability estimates for 361 blood metabolites across 40 genome-wide association studies

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    Metabolomics examines the small molecules involved in cellular metabolism. Approximately 50% of total phenotypic differences in metabolite levels is due to genetic variance, but heritability estimates differ across metabolite classes. We perform a review of all genome-wide association and (exome-) sequencing studies published between November 2008 and October 2018, and identify >800 class-specific metabolite loci associated with metabolite levels. In a twin-family cohort (N = 5117), these metabolite loci are leveraged to simultaneously estimate total heritability (h2 total), and the proportion of heritability captured by known metabolite loci (h2 Metabolite-hits) for 309 lipids and
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