Aims We aimed to update the logistic clinical SYNTAX score to predict 2 year all-cause mortality after contemporary percutaneous coronary intervention (PCI).Methods and results We analyzed 15,883... Show moreAims We aimed to update the logistic clinical SYNTAX score to predict 2 year all-cause mortality after contemporary percutaneous coronary intervention (PCI).Methods and results We analyzed 15,883 patients in the GLOBAL LEADERS study who underwent PCI. The logistic clinical SYNTAX model was updated after imputing missing values by refitting the original model (refitted original model) and fitting an extended new model (new model, with, selection based on the Akaike Information Criterion). External validation was performed in 10,100 patients having PCI at Fu Wai hospital.Chronic obstructive pulmonary disease, prior stroke, current smoker, hemoglobin level, and white blood cell count were identified as additional independent predictors of 2 year all-cause mortality and included into the new model.The c-indexes of the original, refitted original and the new model in the derivation cohort were 0.74 (95% CI 0.72-0.76), 0.75 (95% CI 0.73-0.77), and 0.78 (95% CI 0.76-0.80), respectively. The c-index of the new model was lower in the validation cohort than in the derivation cohort, but still showed improved discriminative ability of the newly developed model (0.72; 95% CI 0.67-0.77) compared to the refitted original model (0.69; 95% CI 0.64-0.74). The models overestimated the observed 2 year all-cause mortality of 1.11% in the Chinese external validation cohort by 0.54 percentage points, indicating the need for calibration of the model to the Chinese patient population.Conclusions The new model of the logistic clinical SYNTAX score better predicts 2 year all-cause mortality after PCI than the original model. The new model could guide clinical decision making by risk stratifying patients undergoing PCI. Show less
Background and aims: The impact of endothelial shear stress (ESS) on vessel remodeling in vessels implanted with bioresorbable scaffold (BRS) as compared to metallic drug-eluting stent (DES)... Show moreBackground and aims: The impact of endothelial shear stress (ESS) on vessel remodeling in vessels implanted with bioresorbable scaffold (BRS) as compared to metallic drug-eluting stent (DES) remains elusive. The aim of this study was to determine whether the relationship between ESS and remodeling patterns differs in BRS from those seen in metallic DES at 3-year follow-up.Methods: In the ABSORB II randomized trial, lesions were investigated by serial coronary angiography and intravascular ultrasound (IVUS). Three-dimensional reconstructions of coronary arteries post-procedure and at 3 years were performed. ESS was quantified using non-Newtonian steady flow simulation. IVUS cross-sections in device segment were matched using identical landmarks.Results: Paired ESS calculations post-procedure and at 3 years were feasible in 57 lesions in 56 patients. Post-procedure, median ESS at frame level was higher in BRS than in DES, with marginal statistical significance (0.97 +/- 0.48 vs. 0.75 +/- 0.39 Pa, p = 0.063). In the BRS arm, vessel area and lumen area showed larger increases in the highest tercile of median ESS post-procedure as compared to the lowest tercile. In contrast, in DES, no significant relationship between median ESS post-procedure and remodeling was observed. In multivariate analysis, smaller vessel area, larger lumen area, higher plaque burden post-procedure, and higher median ESS post-procedure were independently associated with expansive remodeling in matched frames. Only in BRS, younger age was an additional significant predictor of expansive remodeling.Conclusions: In a subset of lesions with large plaque burden, shear stress could be associated with expansive remodeling and late lumen enlargement in BRS, while ESS had no impact on vessel dimension in metallic DES. Show less
Background Randomised controlled trials are considered the gold standard for testing the efficacy of novel therapeutic interventions, and typically report the average treatment effect as a summary... Show moreBackground Randomised controlled trials are considered the gold standard for testing the efficacy of novel therapeutic interventions, and typically report the average treatment effect as a summary result. As the result of treatment can vary between patients, basing treatment decisions for individual patients on the overall average treatment effect could be suboptimal. We aimed to develop an individualised decision making tool to select an optimal revascularisation strategy in patients with complex coronary artery disease.Methods The SYNTAX Extended Survival (SYNTAXES) study is an investigator-driven extension follow-up of a multicentre, randomised controlled trial done in 85 hospitals across 18 North American and European countries between March, 2005, and April, 2007. Patients with de-novo three-vessel and left main coronary artery disease were randomly assigned (1:1) to either the percutaneous coronary intervention (PCI) group or coronary artery bypass grafting (CABG) group. The SYNTAXES study ascertained 10-year all-cause deaths. We used Cox regression to develop a clinical prognostic index for predicting death over a 10-year period, which was combined, in a second stage, with assigned treatment (PCI or CABG) and two prespecified effect-modifiers, which were selected on the basis of previous evidence: disease type (three-vessel disease or left main coronary artery disease) and anatomical SYNTAX score. We used similar techniques to develop a model to predict the 5-year risk of major adverse cardiovascular events (defined as a composite of all-cause death, non-fatal stroke, or non-fatal myocardial infarction) in patients receiving PCI or CABG. We then assessed the ability of these models to predict the risk of death or a major adverse cardiovascular event, and their differences (ie, the estimated benefit of CABG versus PCI by calculating the absolute risk difference between the two strategies) by cross-validation with the SYNTAX trial (n=1800 participants) and external validation in the pooled population (n=3380 participants) of the FREEDOM, BEST, and PRECOMBAT trials. The concordance (C)-index was used to measure discriminative ability, and calibration plots were used to assess the degree of agreement between predictions and observations.Findings At cross-validation, the newly developed SYNTAX score II, termed SYNTAX score II 2020, showed a helpful discriminative ability in both treatment groups for predicting 10-year all-cause deaths (C-index=0.73 [95% CI 0.69-0.76] for PCI and 0.73 [0.69-0.76] for CABG) and 5-year major adverse cardiovascular events (C-index=0.65 [0.61-0.69] for PCI and C-index=0.71 [0.67-0.75] for CABG). At external validation, the SYNTAX score II 2020 showed helpful discrimination (C-index=0.67 [0.63-0.70] for PCI and C-index=0.62 [0.58-0.66] for CABG) and good calibration for predicting 5-year major adverse cardiovascular events. The estimated treatment benefit of CABG over PCI varied substantially among patients in the trial population, and the benefit predictions were well calibrated.Interpretation The SYNTAX score II 2020 for predicting 10-year deaths and 5-year major adverse cardiovascular events can help to identify individuals who will benefit from either CABG or PCI, thereby supporting heart teams, patients, and their families to select optimal revascularisation strategies. Copyright (C) 2020 Elsevier Ltd. All rights reserved. Show less
Aims: The aim of this study was to assess the acute performance of the 95 mu m ArterioSorb oriented poly L-lactic acid (PLLA) scaffold in comparison with the XIENCE metallic drug-eluting stent (DES... Show moreAims: The aim of this study was to assess the acute performance of the 95 mu m ArterioSorb oriented poly L-lactic acid (PLLA) scaffold in comparison with the XIENCE metallic drug-eluting stent (DES) in porcine coronary arteries.Methods and results: In 15 non-atherosclerotic Yucatan mini pigs, the ArterioSorb (3.0/14 mm) and XIENCE (3.0/15 mm) were implanted in 25 and 15 vessels, respectively. Acute performance was evaluated by using quantitative coronary angiography (QCA) and optical coherence tomography (OCT). Following three-dimensional reconstruction of the coronary arteries, endothelial shear stress (ESS) was quantified using non-Newtonian steady-flow simulation. Acute recoil measured by QCA was comparable in the two aims. Post-procedural flow and scaffold/stent area by OCT did not differ between the two devices. ESS post procedure was comparable between ArterioSorb and XIENCE (2.21 +/- 1.97 vs 2.25 +/- 1.71 Pa, p=0.314).Conclusions: Acute recoil, luminal dimensions and ESS in the ArterioSorb oriented PLLA scaffold with thin struts of 95 mu m were comparable to those in the XIENCE metallic DES. Show less
OBJECTIVES The aim of this study was to investigate the impact of post-percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) on clinical outcomes in patients with de novo 3-vessel... Show moreOBJECTIVES The aim of this study was to investigate the impact of post-percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) on clinical outcomes in patients with de novo 3-vessel disease (3VD) treated with contemporary PCI.BACKGROUND The clinical impact of post-PCI QFR in patients treated with state-of-the-art PCI for de novo 3VD is undetermined.METHODS All vessels treated in the SYNTAX (SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery) II trial were retrospectively screened and analyzed for post-PCI QFR. The primary endpoint of this substudy was vessel-oriented composite endpoint (VOCE) at 2 years, defined as the composite of vessel-related cardiac death, vessel-related myocardial infarction, and target vessel revascularization. The receiver-operating characteristic curve was used to calculate the optimal cutoff value of post-PCI QFR for predicting 2-year VOCE. All the analyzable vessels were stratified on the basis of the optimal cutoff value.RESULTS A total of 968 vessels treated with PCI were screened. Post-PCIQFR was analyzable in 771 (79.6%) vessels. A total of 52 (6.7%) VOCEs occurredat 2 years. The mean value of post-PCIQFR was 0.91 +/- 0.07. The diagnostic performance of post-PCI QFR to predict 2-year VOCE was moderate (area under the curve: 0.702; 95% confidence interval: 0.633 to 0.772), with the optimal cutoff value of post-PCI QFR for predicting 2-year VOCE 0.91 (sensitivity 0.652, specificity 0.635). The incidence of 2-year VOCE in the vessels with post-PCIQFR<0.91 (n = 284) was significantly higher compared with vessels with post-PCI QFR >= 0.91 (n = 487) (12.0% vs. 3.7%; hazard ratio: 3.37; 95% confidence interval: 1.91 to 5.97; p < 0.001).CONCLUSIONS A higher post-PCI QFR value is associated with improved vessel-related clinical outcomes in state-of the art PCI practice for de novo 3VD. Achieving a post-PCI QFR value >= 0.91 in all treated vessels should be a target when treating de novo 3VD. These findings require confirmation in future prospective trials. (C) 2019 by the American College of Cardiology Foundation. Show less
ImportanceAlthough IgA nephropathy (IgAN) is the most common glomerulonephritis in the world, there is no validated tool to predict disease progression. This limits patient-specific risk... Show moreImportanceAlthough IgA nephropathy (IgAN) is the most common glomerulonephritis in the world, there is no validated tool to predict disease progression. This limits patient-specific risk stratification and treatment decisions, clinical trial recruitment, and biomarker validation. ObjectiveTo derive and externally validate a prediction model for disease progression in IgAN that can be applied at the time of kidney biopsy in multiple ethnic groups worldwide. Design, Setting, and ParticipantsWe derived and externally validated a prediction model using clinical and histologic risk factors that are readily available in clinical practice. Large, multi-ethnic cohorts of adults with biopsy-proven IgAN were included from Europe, North America, China, and Japan. Main Outcomes and MeasuresCox proportional hazards models were used to analyze the risk of a 50% decline in estimated glomerular filtration rate (eGFR) or end-stage kidney disease, and were evaluated using the R-D(2) measure, Akaike information criterion (AIC), C statistic, continuous net reclassification improvement (NRI), integrated discrimination improvement (IDI), and calibration plots. ResultsThe study included 3927 patients; mean age, 35.4 (interquartile range, 28.0-45.4) years; and 2173 (55.3%) were men. The following prediction models were created in a derivation cohort of 2781 patients: a clinical model that included eGFR, blood pressure, and proteinuria at biopsy; and 2 full models that also contained the MEST histologic score, age, medication use, and either racial/ethnic characteristics (white, Japanese, or Chinese) or no racial/ethnic characteristics, to allow application in other ethnic groups. Compared with the clinical model, the full models with and without race/ethnicity had better R-D(2) (26.3% and 25.3%, respectively, vs 20.3%) and AIC (6338 and 6379, respectively, vs 6485), significant increases in C statistic from 0.78 to 0.82 and 0.81, respectively (Delta C, 0.04; 95% CI, 0.03-0.04 and Delta C, 0.03; 95% CI, 0.02-0.03, respectively), and significant improvement in reclassification as assessed by the NRI (0.18; 95% CI, 0.07-0.29 and 0.51; 95% CI, 0.39-0.62, respectively) and IDI (0.07; 95% CI, 0.06-0.08 and 0.06; 95% CI, 0.05-0.06, respectively). External validation was performed in a cohort of 1146 patients. For both full models, the C statistics (0.82; 95% CI, 0.81-0.83 with race/ethnicity; 0.81; 95% CI, 0.80-0.82 without race/ethnicity) and R-D(2) (both 35.3%) were similar or better than in the validation cohort, with excellent calibration. Conclusions and RelevanceIn this study, the 2 full prediction models were shown to be accurate and validated methods for predicting disease progression and patient risk stratification in IgAN in multi-ethnic cohorts, with additional applications to clinical trial design and biomarker research. Show less
Optical coherence tomography based computational flow dynamic (CFD) modeling provides detailed information about the local flow behavior in stented/scaffolded vessel segments. Our aim is to... Show moreOptical coherence tomography based computational flow dynamic (CFD) modeling provides detailed information about the local flow behavior in stented/scaffolded vessel segments. Our aim is to investigate the in-vivo effect of strut thickness and strut protrusion on endothelial wall shear stress (ESS) distribution in ArterioSorb Absorbable Drug-Eluting Scaffold (ArterioSorb) and Absorb everolimus-eluting Bioresorbable Vascular Scaffold (Absorb) devices that struts with similar morphology (quadratic structure) but different thickness. In three animals, six coronary arteries were treated with ArterioSorb. At different six animals, six coronary arteries were treated with Absorb. Following three-dimensional(3D) reconstruction of the coronary arteries, Newtonian steady flow simulation was performed and the ESS were estimated. Mixed effects models were used to compare ESS distribution in the two devices. There were 4591 struts in the analyzed 477 cross-sections in Absorb (strut thickness=157 mu m) and 3105 struts in 429 cross-sections in ArterioSorb (strut thickness=95 mu m) for the protrusion analysis. In cross-section level analysis, there was significant difference between the scaffolds in the protrusion distances. The protrusion was higher in Absorb (97% of the strut thickness) than in ArterioSorb (88% of the strut thickness). ESS was significantly higher in ArterioSorb (1.52 +/- 0.34Pa) than in Absorb (0.73 +/- 2.19Pa) (p=0.001). Low- and very-low ESS data were seen more often in Absorb than in ArterioSorb. ArterioSorb is associated with a more favorable ESS distribution compared to the Absorb. These differences should be attributed to different strut thickness/strut protrusion that has significant effect on shear stress distribution. Show less
OBJECTIVES The aims of the present study were to investigate the applicability of quantitative flow ratio (QFR) in patients with 3-vessel disease and to demonstrate the impact of functional SYNTAX ... Show moreOBJECTIVES The aims of the present study were to investigate the applicability of quantitative flow ratio (QFR) in patients with 3-vessel disease and to demonstrate the impact of functional SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) score derived from QFR (fSS(QFR)) on clinical outcomes.BACKGROUND The applicability of QFR in patients with 3-vessel disease and the feasibility of fSS(QFR) have not yet been investigated.METHODS All lesions interrogated using instantaneous wave-free ratio and/or fractional flow reserve in the SYNTAX II trial were retrospectively screened and analyzed for QFR. The diagnostic performance of QFR was investigated using hybrid wire-derived pressure assessment (instantaneous wave-free ratio and fractional flow reserve), used in the trial as a reference. Patients with analyzable QFR in 3 vessels were stratified according to fSS(QFR) to evaluate its clinical prognostic value on the basis of 2-year patient-oriented composite endpoint.RESULTS QFRs were analyzable in 71.0% of lesions (836 lesions). The diagnostic performance of QFR to predict binary wire-based ischemia was substantial (area under the curve 0.81, accuracy 73.8%), with a positive predictive value of 85.9%. Independent predictors of diagnostic discordance were lesions in side branches, involvement of bifurcation or trifurcation, and small vessel. According to the 2-year patient-oriented composite endpoint, fSS(QFR) reclassified 26.1% of the patients (36 of 138) in the high-to intermediate-risk group into the low-risk group appropriately (net reclassification improvement 0.32; p < 0.001). The area under the curve for fSS(QFR) to predict the 2-year patient-oriented composite endpoint was higher than that of the classic anatomic SYNTAX score (0.68 vs. 0.56; p = 0.002).CONCLUSIONS QFR demonstrated substantial applicability in patients with 3-vessel disease. The fSS(QFR) has the potential to further refine prognostic risk estimation compared with the classic anatomic SYNTAX score. (c) 2019 by the American College of Cardiology Foundation. Show less
Beardsley, P.A.; Johnston-Hillitt, M.; Trott, M.C.; Prober, C.J.; Morgan, J.; Oberoi, D.; ... ; Wu, C. 2019
The Murchison Widefield Array (MWA) is an open access telescope dedicated to studying the low-frequency (80-300 MHz) southern sky. Since beginning operations in mid-2013, the MWA has opened a new... Show moreThe Murchison Widefield Array (MWA) is an open access telescope dedicated to studying the low-frequency (80-300 MHz) southern sky. Since beginning operations in mid-2013, the MWA has opened a new observational window in the southern hemisphere enabling many science areas. The driving science objectives of the original design were to observe 21 cm radiation from the Epoch of Reionisation (EoR), explore the radio time domain, perform Galactic and extragalactic surveys, and monitor solar, heliospheric, and ionospheric phenomena. All together 60+ programs recorded 20 000 h producing 146 papers to date. In 2016, the telescope underwent a major upgrade resulting in alternating compact and extended configurations. Other upgrades, including digital back-ends and a rapid-response triggering system, have been developed since the original array was commissioned. In this paper, we review the major results from the prior operation of the MWA and then discuss the new science paths enabled by the improved capabilities. We group these science opportunities by the four original science themes but also include ideas for directions outside these categories.... Show less
Induced pluripotent stem cells (iPSCs) are novel stem cells derived from adult mouse and human tissues by reprogramming. Elucidation of mechanisms and exploration of efficient methods for their... Show moreInduced pluripotent stem cells (iPSCs) are novel stem cells derived from adult mouse and human tissues by reprogramming. Elucidation of mechanisms and exploration of efficient methods for their differentiation to functional cardiomyocytes are essential for developing cardiac cell models and future regenerative therapies. We previously established a novel mouse embryonic stem cell (ESC) and iPSC differentiation system in which cardiovascular cells can be systematically induced from Flk1(+) common progenitor cells, and identified highly cardiogenic progenitors as Flk1(+)/CXCR4(+)/VE-cadherin(-) (FCV) cells. We have also reported that cyclosporin-A (CSA) drastically increases FCV progenitor and cardiomyocyte induction from mouse ESCs. Here, we combined these technologies and extended them to mouse and human iPSCs. Co-culture of purified mouse iPSC-derived Flk1(+) cells with OP9 stroma cells induced cardiomyocyte differentiation whilst addition of CSA to Flk1(+) cells dramatically increased both cardiomyocyte and FCV progenitor cell differentiation. Spontaneously beating colonies were obtained from human iPSCs by co-culture with END-2 visceral endoderm-like cells. Appearance of beating colonies from human iPSCs was increased approximately 4.3 times by addition of CSA at mesoderm stage. CSA-expanded human iPSC-derived cardiomyocytes showed various cardiac marker expressions, synchronized calcium transients, cardiomyocyte-like action potentials, pharmacological reactions, and ultra-structural features as cardiomyocytes. These results provide a technological basis to obtain functional cardiomyocytes from iPSCs. Show less