A cooperative palladium/triorganoboron catalyst to accomplish the intramolecular aminocyanation of alkenes through the cleavage of N–CN bonds is reported. ...4,5-Bis(diphenylphosphino)-9,9-dimethylxanthene (Xantphos) is found to be crucial as a ligand for palladium to effectively catalyze the transformation with high chemo- and regioselectivity. A range of substituted indolines and pyrrolidines with both tetra- or trisubstituted carbon and cyano functionalities are readily furnished by the newly developed cyanofunctionalization reaction. A preliminary example of enantioselective aminocyanation is also described.
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IJS, KILJ, NUK, PNG, UL, UM
Background: Transcatheter aortic valve implantation (TAVI) is increasingly being performed in very elderly patients, although its efficacy and validity remain unclear. This study evaluated real-world ...TAVI outcomes in Japanese nonagenarians with severe aortic stenosis.Methods and Results: This single-center study retrospectively assessed the early and long-term clinical outcomes of TAVI in nonagenarians (n=35) and in patients aged <90 years (group Y; n=171). There were no in-hospital deaths in either group. The device success rate and early safety were comparable between the 2 groups. The 5-year rates of freedom from cardiac events and deaths were equivalent in both groups. The cumulative survival rate at 5 years was non-significantly lower in nonagenarians (32.6% in nonagenarians vs. 57.5% in patients aged <90 years, P=0.49). There were no differences in the 5-year survival between nonagenarians after TAVI and the sex- and age-matched populations (P=0.18). The Cox regression model revealed that lower hemoglobin levels were associated with all-cause mortality (P=0.02), and age ≥90 years was not associated with all-cause mortality.Conclusions: The early and long-term clinical outcomes of TAVI for selected Japanese nonagenarians were comparable to those in patients aged <90 years. Nonagenarians who underwent TAVI achieved an acceptable prognosis compared to the sex- and age-matched population; thus, TAVI appears to be effective for treating aortic stenosis in Japanese nonagenarians.
Abstract
Aims
Pressure-wire assessment of coronary stenosis is considered the invasive reference standard for detection of ischaemia-generating lesions. Recently, methods to estimate the fractional ...flow reserve (FFR) from conventional angiography without the use of a pressure wire have been developed, and were shown to have an excellent diagnostic accuracy. The present systematic review and meta-analysis aimed at determining the diagnostic performance of angiography-derived FFR for the diagnosis of haemodynamically significant coronary artery disease.
Methods and results
A systematic review and meta-analysis of studies assessing the diagnostic performance of angiography-derived FFR systems were performed. The primary outcome of interest was pooled sensitivity and specificity. Thirteen studies comprising 1842 vessels were included in the final analysis. A Bayesian bivariate meta-analysis yielded a pooled sensitivity of 89% (95% credible interval 83–94%), specificity of 90% (95% credible interval 88–92%), positive likelihood ratio (+LR) of 9.3 (95% credible interval 7.3–11.7) and negative likelihood ratio (−LR) of 0.13 (95% credible interval 0.07–0.2). The summary area under the receiver-operating curve was 0.84 (95% credible interval 0.66–0.94). Meta-regression analysis did not find differences between the methods for pressure-drop calculation (computational fluid dynamics vs. mathematical formula), type of analysis (on-line vs. off-line) or software packages.
Conclusion
The accuracy of angiography-derived FFR was good to detect haemodynamically significant lesions with pressure-wire measured FFR as a reference. Computational approaches and software packages did not influence the diagnostic accuracy of angiography-derived FFR. A diagnostic strategy trial with angiography-derived FFR evaluating clinical endpoints is warranted.
Background: Side branch (SB) occlusion during bifurcation stenting is a serious complication. This study aimed to predict SB compromise (SBC) using optical coherence tomography (OCT).Methods and ...Results: Among the 168 patients who enrolled in the 3D-OCT Bifurcation Registry, 111 bifurcation lesions were analyzed to develop an OCT risk score for predicting SBC. SBC was defined as worsening of angiographic SB ostial stenosis (≥90%) immediately after stenting. On the basis of OCT before stenting, geometric parameters (SB diameter SBd, length from proximal branching point to carina tip BP-CT length, and distance of the polygon of confluence dPOC) and 3-dimensional bifurcation types (parallel or perpendicular) were evaluated. SBC occurred in 36 (32%) lesions. The parallel-type bifurcation was significantly more frequent in lesions with SBC. The receiver operating characteristic curve indicated SBd ≤1.77 mm (area under the curve AUC=0.73, sensitivity 64%, specificity 75%), BP-CT length ≤1.8 mm (AUC=0.83, sensitivity 86%, specificity 68%), and dPOC ≤3.96 mm (AUC=0.68, sensitivity 63%, specificity 69%) as the best cut-off values for predicting SBC. To create the OCT risk score, we assigned 1 point to each of these factors. As the score increased, the frequency of SBC increased significantly (Score 0, 0%; Score 1, 8.7%; Score 2, 28%; Score 3, 58%; Score 4, 85%; P<0.0001).Conclusions: Prediction of SBC using OCT is feasible with high probability.
The pyramid-shaped machining test was proposed to evaluate error motions of a five-axis machine tool. This paper presents software to perform and analyze the pyramid-shaped machining test. The paper ...presents an extension of the analysis algorithm to a five-axis machine tool with two rotary axes on the tool side. An experimental case study shows that position and orientation errors (location errors) of rotary axis average lines, as well as position-dependent error motions of a rotary axis, can be numerically identified from geometric errors of the finished test piece. Experimental demonstration of the numerical compensation of rotary axis geometric errors based on the R-test is also presented, along with its performance investigation by the present machining test. The developed software is commercially available.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Background:The clinical robustness of contrast-videodensitometric (VD) assessment of aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI) has been demonstrated. Correct ...acquisition of aortic root angiography for VD assessment, however, is hampered by the opacified descending aorta and by individual anatomic peculiarities. The aim of this study was to use preprocedural multi-slice computed tomography (MSCT) to optimize the angiographic projection in order to improve the feasibility of VD assessment.Methods and Results:In 92 consecutive patients, post-TAVI AR (i.e., left ventricular outflow tract LVOT AR) was assessed on aortic root angiograms using VD software. The patients were divided into 2 groups: The first group of 54 patients was investigated prior to the introduction of the standardized acquisition protocol; the second group of 38 consecutive patients after implementation of the standardized acquisition protocol, involving MSCT planning of the optimal angiographic projection. Optimal projection planning has dramatically improved the feasibility of VD assessment from 57.4% prior to the standardized acquisition protocol, to 100% after the protocol was implemented. In 69 analyzable aortograms (69/92; 75%), LVOT-AR ranged from 3% to 28% with a median of 12%. Inter-observer agreement was high (mean difference±SD, 1±2%), and the 2 observers’ measurements were highly correlated (r=0.94, P<0.0001).Conclusions:Introduction of computed tomography-guided angiographic image acquisition has significantly improved the analyzability of the angiographic VD assessment of post-TAVI AR.
To investigate the characteristics of coronary artery bifurcation type (parallel or perpendicular type) using three-dimensional (3D) optical coherence tomography (OCT), and determine the feasibility, ...reproducibility, assessment time and correlation with bifurcation angles measured by 3D quantitative coronary angiography (QCA).
We evaluated 60 lesions at the coronary bifurcation that were treated by main vessel (MV) stenting with kissing balloon inflation (KBI) under OCT/optical frequency domain imaging (OFDI) guidance. Inter- and intra-observer agreement regarding the assessment of 3D bifurcation types were 0.88 and 0.94, respectively. The assessment times of 3D-OCT bifurcation type with OCT and OFDI were within about 30 seconds. 3D-OCT bifurcation types showed the greatest correlation with the distal bifurcation angle assessed by 3D-QCA among the three bifurcation angles (distal bifurcation angle, proximal bifurcation angle and main vessel angle), and the optimal cut-off distal bifurcation angle to predict a perpendicular type bifurcation, as determined by ROC analysis, was 51.0° (AUC 0.773, sensitivity 0.80, specificity 0.67). Based on this cut-off value for the distal bifurcation angle (51°), the diagnostic accuracy for perpendicular type bifurcation in cases with a BA ≥ 51° (n = 34) was 70.6% (24/34) and that of the parallel type bifurcation in cases of BA < 51° (n = 26) was 76.9% (20/26).
Performing 3D-OCT for assessment of coronary artery bifurcation type is feasible and simple, and can be done in a short time with high reproducibility.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A beneficial surrogate marker for evaluating the effect of medical therapy is warranted to avoid deferred lesion revascularization. Similar to coronary artery imaging for monitoring the effects of ...medical therapy by analyzing plaque regression and stabilization, we hypothesized that evaluation of serial changes in the quantitative flow ratio (QFR) would serve as a surrogate marker of the effects of medical therapy against deferred lesion revascularization. Here, we investigated serial changes in QFR over time after percutaneous coronary intervention in patients who underwent medical therapy as a secondary prevention. Patients with intermediate stenosis in an untreated vessel observed at the baseline (BL) coronary angiography and follow-up (FU) coronary angiography performed 6–18 months after BL angiography were screened in 2 centers. A total of 52 patients were able to analyze both BL and FU QFR. The median QFR was 0.83 (IQR, 0.69, 0.89) at BL and 0.80 (IQR, 0.70, 0.86) at FU. The number of positive ΔQFR and negative ΔQFR were 21 and 31, respectively. The median ΔQFR was 0.05 (IQR, 0.03, 0.09) in positive ΔQFR and – 0.05 (IQR, – 0.07, – 0.03) in negative ΔQFR (
p
< 0.0001). Univariate and multivariate analyses revealed that LDL-C at FU predicted improvement in the QFR (OR 0.95, 95% confidence interval 0.91, 0.98,
P
= 0.001). Assessment of serial changes in the QFR may serve as a surrogate marker for the effects of medical therapy in patients with residual intermediate coronary stenosis.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Establishing sampling techniques for juveniles of tuna species is essential for understanding their ecology and population dynamics because only individuals showing rapid growth during larval and ...juvenile stages are able to survive. This study is the first report on the successful sampling of juveniles of tuna species using the larva catcher (LC)-type trawl net, a pelagic trawl gear with a 10 × 10-m mouth opening, 40-m total length, and 5 × 5-mm mesh size. It was used in a research cruise in May-June 2009. The LC net was horizontally towed for 30 min at depths of 0 m-10 m at speeds of about 1.8 m/s. Overall, 66 and 163 juveniles of Pacific bluefin tuna (PBT) and yellowfin tuna (YFT) were collected; the standard length (SL) of the PBT and YFT ranged from 15.0 to 29.7 mm and 11.7 to 34.8 mm, respectively. The total operation time for the trawls of the LC-type net was much shorter than that of the usual trawls; therefore, a larger number of operations can be conducted in a day. We concluded that the LC-type trawl net can be used for collecting tuna juveniles because of its catchability and ease of operation.
Background: P2Y12 inhibitor monotherapy without aspirin immediately after percutaneous coronary intervention (PCI) has not been tested in East Asian patients, so in this study we aimed to assess the ...safety and feasibility of reduced dose (3.75 mg/day) prasugrel monotherapy in Japanese patients presenting with chronic coronary syndrome (CCS).Methods and Results: ASET-JAPAN is a prospective, multicenter, single-arm pilot study that completed enrolment of 206 patients from 12 Japanese centers in September 2022. Patients with native de-novo coronary lesions and a SYNTAX score <23 were treated exclusively with biodegradable-polymer platinum-chromium everolimus-eluting stent(s). Patients were loaded with standard dual antiplatelet therapy (DAPT) and following successful PCI and optimal stent deployment, they received low-dose prasugrel (3.75 mg/day) monotherapy for 3 months. The primary ischemic endpoint was a composite of cardiac death, spontaneous target-vessel myocardial infarction, or definite stent thrombosis. The primary bleeding endpoint was Bleeding Academic Research Consortium (BARC) type 3 or 5. At 3-month follow-up, there were no primary bleeding or ischemic events, or any stent thrombosis.Conclusions: This pilot study showed the safety and feasibility of prasugrel monotherapy in selected low-risk Japanese patients with CCS. This “aspirin-free” strategy may be a safe alternative to traditional DAPT following PCI.
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