Risk Assessment of Side Branch Compromise After Coronary Bifurcation Stenting　- A Substudy of the 3D-OCT Bifurcation Registry.

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.

Prasugrel Monotherapy After Percutaneous Coronary Intervention With Biodegradable-Polymer Platinum-Chromium Everolimus Eluting Stent for Japanese Patients With Chronic Coronary Syndrome (ASET-JAPAN).

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.

Early and Long-Term Outcomes of Transcatheter Aortic Valve Replacement for Selected Nonagenarians in Japan.

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.

Serial changes in the quantitative flow ratio in patients with intermediate residual stenosis after percutaneous coronary intervention.

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.

Feasibility study of a synchronized diastolic injection with low contrast volume for proper quantitative assessment of aortic regurgitation in porcine models.

OBJECTIVES: To evaluate the in vivo feasibility of aortography with one accurately timed diastolic low-volume contrast injection for quantitative assessment of aortic regurgitation (AR) post transcatheter aortic valve replacement (TAVR). BACKGROUND: With the rise of a minimalistic approach for TAVR, aortography (re)emerges as a pragmatic tool for AR assessment. In a mock circulation system, we have validated the accuracy of a single diastolic injection triggered by electrocardiogram (ECG) with low-contrast volume. METHODS: Two-phase experiment: first, a series of aortograms were performed in a porcine model, with 8 mL of contrast using the synchronized (SYNC) and the conventional non-synchronized (NS) injections. In a second phase, we developed a model of AR by inserting partially unsheathed Wallstents of 6-10 mm of diameter across the pig's aortic valve, performing SYNC injections with 8 mL of contrast and NS injections with 8 mL and 15 mL (rate: 20 mL/sec). Respective accuracies of SYNC vs. NS were assessed using Passing-Bablock regression. An angiography core laboratory performed quantitative AR assessment with videodensitometry (VD-AR). RESULTS: The SYNC injections produced higher opacification of the aortic root compared with NS injections (P = 0.04 for density). In the second phase, a regression line for predicting VD-AR based on the SYNC injection resulted in a lower intercept and a slope closer to the line of identity (y = 11.9 + 0.79x, P < 0.001, r2 = 0.94) with the NS-8 mL than with the NS-15 mL injection (y = 26.5 + 0.55x, P < 0.001, r2 = 0.81). CONCLUSION: Synchronized diastolic injection with low contrast volume produced denser images in the aortic root and more accurate than the conventional injection; thus, may be an appealing alternative for assessment of AR post TAVR.

Serial Optical Coherence Tomography at Baseline, 7 Days, and 1, 3, 6 and 12 Months After Bioresorbable Scaffold Implantation in a Growing Porcine Model.

BACKGROUND: Little is known about serial changes in lumen and device dimensions after bioresorbable scaffold implantation in a growing animal model. Methods and Results: ABSORB (n=14) or bare metal stents (ICROS amg [Abbott Vascular, Santa Clara, CA, USA], Winsen-Luhe, Germany; n=15) were implanted in the coronary arteries of domestic swine (a hybrid of Finnish-Norwegian Landrace swine) weighing 30-35 kg. Angiography and optical coherence tomography (OCT) were performed immediately after implantation and repeated at 7 days, 1, 3, 6 and 12 months after the index procedure. One month after implantation, mean lumen area decreased relative to baseline in both groups (relative area change from baseline, -41.4±15.6% for ABSORB vs. -20.9±18.6% for ICROS) while mean device area decreased only in the ABSORB group (relative area change: -11.1±9.4% vs. +0.14±7.95%, respectively). At 12 months, mean lumen area increased relative to baseline in both groups (relative area change from baseline, +55.6±22.4% vs. +32.3±83.6%, respectively) in accordance with the swine growth weighing up to 260-300 kg. Mean device area in the ICROS group remained stable whereas that in the ABSORB group began to increase between 3 and 6 months along with the vessel growth (relative area change: +107.8±25.7% vs. +0.14±7.95%). CONCLUSIONS: In the growing porcine model, ABSORB was associated with greater extent of recoil 1 month after implantation compared with ICROS but demonstrated substantial adaptability to vessel growth in late phase.

Angiographic late lumen loss revisited: impact on long-term target lesion revascularization.

Aim: In current device trials, the values of angiographic late lumen loss (LLL) have become extremely low and the relationship between LLL and clinical endpoints has not been recently re-evaluated. The impact of LLL on target lesion revascularization (TLR) in a patient- and study-level analysis of contemporary coronary devices was investigated. Methods and results: We performed a patient-level meta-analysis of seven randomized controlled trials including 2426 patients treated with first- and second-generation drug-eluting stents (DES) and a study-level meta-analysis of 40 studies including 19 199 patients treated with CE-marked DES. In the patient-level analysis, the probability regression curve showed an exponential relationship between in-stent LLL and 2-year incidence of TLR. The optimal cut-off value of LLL based on Youden's index for 2-year TLR event was 0.50 mm. In the Cox proportional hazard model, LLL >0.50 mm was independently associated with an increased incidence of TLR up to 4 years after angiographic follow-up {adjusted hazard ratio (HR) 6.62 [95% confidence interval (95% CI) 4.67-9.39], P < 0.001}. In the meta-regression analysis of the DES studies, pooled mean value of LLL was as low as 0.23 mm (95% CI 0.20-0.26), and there was a moderate correlation between the 1- and 5-year incidence of TLR and the percentage of the lesions with LLL >0.50 mm (R2 = 0.44, P < 0.001 at 1 year, R2 = 0.40, P < 0.001 at 5 years). Conclusion: An angiographic LLL ≤0.50 mm was not predictive of the incidence of TLR whereas a LLL >0.50 mm was. Low LLL in contemporary device trials may not be a sufficiently discriminating parameter for the comparative evaluation of devices.

Coronary computed tomography angiography for heart team decision-making in multivessel coronary artery disease.

Aims: Coronary computed tomography angiography (CTA) has emerged as a non-invasive diagnostic method for patients with suspected coronary artery disease, but its usefulness in patients with complex coronary artery disease remains to be investigated. The present study sought to determine the agreement between separate heart teams on treatment decision-making based on either coronary CTA or conventional angiography. Methods and results: Separate heart teams composed of an interventional cardiologist, a cardiac surgeon, and a radiologist were randomized to assess the coronary artery disease with either coronary CTA or conventional angiography in patients with de novo left main or three-vessel coronary artery disease. Each heart team, blinded for the other imaging modality, quantified the anatomical complexity using the SYNTAX score and integrated clinical information using the SYNTAX Score II to provide a treatment recommendations based on mortality prediction at 4 years: coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI), or equipoise between CABG and PCI. The primary endpoint was the agreement between heart teams on the revascularization strategy. The secondary endpoint was the impact of fractional flow reserve derived from coronary CTA (FFRCT) on treatment decision and procedural planning. Overall, 223 patients were included. A treatment recommendation of CABG was made in 28% of the cases with coronary CTA and in 26% with conventional angiography. The agreement concerning treatment decision between coronary CTA and conventional angiography was high (Cohen's kappa 0.82, 95% confidence interval 0.74-0.91). The heart teams agreed on the coronary segments to be revascularized in 80% of the cases. FFRCT was available for 869/1108 lesions (196/223 patients). Fractional flow reserve derived from coronary CTA changed the treatment decision in 7% of the patients. Conclusion: In patients with left main or three-vessel coronary artery disease, a heart team treatment decision-making based on coronary CTA showed high agreement with the decision derived from conventional coronary angiography suggesting the potential feasibility of a treatment decision-making and planning based solely on this non-invasive imaging modality and clinical information. Trial registration number: NCT02813473.

Diagnostic performance of angiography-derived fractional flow reserve: a systematic review and Bayesian meta-analysis.

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.

Determinants of success and hemodynamic impact of balloon postdilatation of self-expanding transcatheter aortic valves.

OBJECTIVES: To explore the rate, the determinants of success, and the hemodynamic impact of balloon postdilatation (BPD) of self-expanding transcatheter heart valves (SE-THVs) BACKGROUND: BPD is commonly used to optimize valve expansion and reduce paravalvular leakage (PVL) after transcatheter aortic valve implantation (TAVI) without clearly knowing its hemodynamic benefits. METHODS: Patients (n = 307) who received a SE-THV were stratified according to whether a BPD was performed or not. Patients who received BPD were stratified according to the severity of PVL remaining after BPD into two groups: Successful BPD (≤mild PVL + BPD) and Failed BPD (moderate-severe PVL + BPD). RESULTS: BPD was performed in 121 patients (39.4%) and was successful in 106 patients (87.6% of attempts). A ratio of the postdilatation balloon diameter to the annulus diameter ≤0.95 was an independent predictor of BPD failure (OR: 10.72 [2.02-56.76], P = .005). Peak transvalvular pressure gradient (PG) was lower in the Successful BPD group (14[12-22] mm Hg) than in the Failed BPD group (18[16-23] mm Hg, P = .029), and did not rise in either group during follow-up (median [IQR], 364[161-739] days). CONCLUSION: BPD was performed in 39% of patients who received a SE-THV, and was successful in the majority of attempts. BPD failure was more likely in patients with a small postdilatation balloon-to-annulus diameter ratio. Effective BPD improved THV hemodynamic performance, and this was maintained in the intermediate-term post-TAVI.

First-in-Man Trial of SiO2 Inert-Coated Bare Metal Stent System in Native Coronary Stenosis　- The AXETIS FIM Trial.

BACKGROUND: A novel bare metal stent with an SiO2coating was developed to prevent excessive neointimal hyperplasia by inertization of the metallic stent surface. The efficacy of the device was demonstrated in a preclinical model. The aim of this first-in-man trial was to assess the safety and feasibility of the new device.Methods and Results:This prospective non-randomized single-arm trial was designed to enroll 35 patients with a de novo coronary lesion. Quantitative coronary angiography and optical coherence tomography (OCT) were performed at the baseline procedure and at the 6-month follow-up. Stent implantation was performed with OCT guidance according to optimal stent implantation criteria. The trial was terminated upon the advice of the data safety monitoring board after enrolling 14 patients due to the high incidence of re-intervention. Optimal OCT implantation criteria were achieved in only 8.3% of lesions. At 6 months, angiographic in-stent late lumen loss as the primary endpoint was 0.77±0.44 mm, and binary restenosis occurred in 33.3% of lesions. At the 6-month OCT, neointimal volume obstruction was 32.8±15.6% with a neointimal thickness of 237±117 µm. At 12 months, the device-oriented composite endpoint (defined as cardiac death, target vessel myocardial infarction, and clinically indicated target lesion revascularization rate) was 33.3%. CONCLUSIONS: In contrast with the preclinical study, the Axetis stent did not efficiently suppress neointimal hyperplasia in humans in this trial.

Role of Computed Tomography in Planning the Appropriate X-Ray Gantry for Quantitative Aortography of Post-transcatheter Aortic Valve Implantation Regurgitation.

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.

Inter-Technique Consistency and Prognostic Value of Intra-Procedural Angiographic and Echocardiographic Assessment of Aortic Regurgitation After Transcatheter Aortic Valve Implantation.

BACKGROUND: We investigated the relationship between intraprocedural angiographic and echocardiographic AR severity after TAVI, and the clinical robustness of angiographic assessment. Methods and Results: In 74 consecutive patients, the echocardiographic circumferential extent (CE) of the paravalvular regurgitant jet was retrospectively measured and graded based on the VARC-2 cut-points; and angiographic post-TAVI AR was retrospectively quantified using contrast videodensitometry (VD) software that calculates the ratio of the contrast time-density integral in the LV outflow tract to that in the ascending aorta (LVOT-AR). Seventy-four echocardiograms immediately after TAVI were analyzable, while 51 aortograms were analyzable for VD. These 51 echocardiograms and VD were evaluated. Median LVOT-AR across the echocardiographic AR grades was as follows: none-trace, 0.07 (IQR, 0.05-0.11); mild, 0.12 (IQR, 0.09-0.15); and moderate, 0.17 (IQR, 0.15-0.22; P<0.05 for none-trace vs. mild, and mild vs. moderate). LVOT-AR strongly correlated with %CE (r=0.72, P<0.0001). At 1 year, the rate of the composite end-point of all-cause death or HF re-hospitalization was significantly higher in >mild AR patients compared with no-mild AR on intra-procedural echocardiography (41.5% vs. 12.4%, P=0.03) as well as in patients with LVOT-AR >0.17 compared with LVOT-AR ≤0.17 (59.5% vs. 16.6%, P=0.03). CONCLUSIONS: VD (LVOT-AR) has good intra-procedural inter-technique consistency and clinical robustness. Greater than mild post-TAVI AR, but not mild post-TAVI AR, is associated with late mortality.

Late thrombotic events after bioresorbable scaffold implantation: a systematic review and meta-analysis of randomized clinical trials.

AIMS: To compare the long-term safety and efficacy of bioresorbable vascular scaffold (BVS) with everolimus-eluting stent (EES) after percutaneous coronary interventions. METHODS AND RESULTS: A systematic review and meta-analysis of randomized clinical trials comparing clinical outcomes of patients treated with BVS and EES with at least 24 months follow-up was performed. Adjusted random-effect model by the Knapp-Hartung method was used to compute odds ratios (OR) and 95% confidence intervals (CI). The primary safety outcome of interest was the risk of definite/probable device thrombosis (DT). The primary efficacy outcome of interest was the risk of target lesion failure (TLF). Five randomized clinical trials (n = 1730) were included. Patients treated with Absorb BVS had a higher risk of definite/probable DT compared with patients treated with EES (OR 2.93, 95%CI 1.37-6.26, P = 0.01). Very late DT (VLDT) occurred in 13 patients [12/996 (1.4%, 95%CI: 0.08-2.5) Absorb BVS vs. 1/701 (0.5%, 95%CI: 0.2-1.6) EES; OR 3.04; 95%CI 1.2-7.68, P = 0.03], 92% of the VLDT in the BVS group occurred in the absence of dual antiplatelet therapy (DAPT). Patients treated with Absorb BVS had a trend towards higher risk of TLF (OR 1.48, 95%CI 0.90-2.42, P = 0.09), driven by a higher risk of target vessel myocardial infarction and ischaemia-driven target lesion revascularization. No difference was found in the risk of cardiac death. CONCLUSION: Compared with EES, the use of Absorb BVS was associated with a higher rate of DT and a trend towards higher risk of TLF. VLDT occurred in 1.4% of the patients, the majority of these events occurred in the absence of DAPT.

Angiographic assessment of aortic regurgitation by video-densitometry in the setting of TAVI: Echocardiographic and clinical correlates.

OBJECTIVES: We sought to investigate a new angiographic method for aortic regurgitation (AR) severity assessment in the setting of transcatheter aortic valve implantation (TAVI). BACKGROUND: AR after TAVI is common but challenging to quantitate, especially in the cath-lab. METHODS: In 228 patients, AR was quantitated before and after TAVI by echocardiography and by video-densitometric analysis of aortograms. Contrast time-density curves for the aortic root (the reference region) and the left ventricular outflow tract, LVOT were generated. LVOT-AR was calculated as the area under the curve of the LVOT as a fraction of the area under the curve of the reference region. RESULTS: LVOT-AR was 0.10 ± 0.08, 0.13 ± 0.10 and 0.28 ± 0.14 in none-trace, mild and moderate-severe post-TAVI AR as defined by echocardiography (P < 0.001) and a cutpoint of >0.17 corresponded to moderate-severe AR on echocardiography (area under the curve = 0.84). At follow-up (median, 496 days), patients with LVOT-AR ≤ 0.17 showed a significant reduction of LV mass index (LVMi; 121 [95-148] vs. 140 [112-169] g/m2 , P = 0.009) and the prevalence of LV hypertrophy (LVH; 64 vs. 88%, P = 0.001) compared to baseline. In patients with LVOT-AR > 0.17, LVMi (149 [121-178] vs. 166 [144-188] g/m2 , P = 0.14) and the prevalence of LVH (74 vs. 87%, P = 0.23) did not show a significant change. Compared to patients with LVOT-AR ≤ 0.17, those with LVOT-AR > 0.17 had an increased 30-day (16.4% vs. 7.1%, P = 0.035) and one year mortality (32.9 vs. 14.2%, log rank P value = 0.001; HR: 2.690 [1.461-4.953], P = 0.001). CONCLUSIONS: LVOT-AR > 0.17 corresponds to greater than mild AR as defined by echocardiography and predicts impaired LV reverse remodeling and increased early and midterm mortality after TAVI. © 2017 Wiley Periodicals, Inc.

Current status of stress myocardial perfusion imaging pharmaceuticals and radiation exposure in Japan: Results from a nationwide survey.

BACKGROUND: Ionizing radiation generated during medical imaging procedures is a matter of concern. However, the current status of radiopharmaceutical use in stress myocardial perfusion imaging (MPI) and the radiation exposure from these radiopharmaceuticals is unknown in Japan. METHODS AND RESULTS: A nationwide survey was conducted from June through July 2016. The questionnaires on the radiopharmaceuticals used and their administered doses during stress MPI were sent to 641 nuclear medicine facilities. The responses were collected from 431 facilities and the effective dose (ED) for an adult with standard body weight was calculated. Forty-three percent of the facilities used only 201TlCl, 35% used only 99mTc radiopharmaceuticals, and the remaining 22% used both. The two main reasons for using 201TlCl instead of 99mTc radiopharmaceuticals were "more familiarity with the usage of 201TlCl than 99mTc radiopharmaceuticals" and "apprehension about increasing the burden of physicians performing tracer injection twice." The mean ED was 14.0 ± 5.5 mSv (range, 3.9 to 25.2 mSv), which was higher than that reported in other countries. CONCLUSIONS: The ED of stress MPI radiopharmaceuticals in Japan is probably higher than the world standard because more than 50% of the facilities still use 201TlCl. We recommend revising the routine stress MPI protocol to reduce the effects of ionizing radiation.

Intramolecular aminocyanation of alkenes by cooperative palladium/boron catalysis.

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.

Weak and strong phase response curves of the onion fly circadian clock at temperature changes of 1 °C and 4 °C.

With increasing soil depth, the amplitude and phase of the daily temperature cycle decreases and is delayed, respectively. The onion fly, Delia antiqua, which pupates at a soil depth of 2-20 cm, advances the eclosion phase of its circadian clock as the temperature amplitude decreases. This "temperature-amplitude response" compensates for the depth-dependent phase delay of the temperature change and ensures eclosion in the early morning. To clarify the physiological mechanisms that induce a temperature-amplitude response, we performed phase-resetting experiments using a 12-h high- or low-temperature pulse with an amplitude of 1 °C or 4 °C. Based on the results obtained, four phase transition curves and four phase response curves were constructed. These curves show that the phase of the eclosion clock shifted more as the magnitude of the temperature change increased. The 24-h temperature cycle delayed, rather than advanced, the phase of the D. antiqua circadian eclosion rhythm. Therefore, we propose that a small phase delay is caused by a small temperature amplitude at a deep site in the soil and a large phase delay is caused by a large temperature amplitude at a shallow site, leading to the temperature-amplitude response exhibited by D. antiqua.

Quantitative flow ratio versus fractional flow reserve for Heart Team decision-making in multivessel disease: the randomised, multicentre DECISION QFR trial.

BACKGROUND: Vessel-level physiological data derived from pressure wire measurements are one of the important determinant factors in the optimal revascularisation strategy for patients with multivessel disease (MVD). However, these may result in complications and a prolonged procedure time. AIMS: The feasibility of using the quantitative flow ratio (QFR), an angiography-derived fractional flow reserve (FFR), in Heart Team discussions to determine the optimal revascularisation strategy for patients with MVD was investigated. METHODS: Two Heart Teams were randomly assigned either QFR- or FFR-based data of the included patients. They then discussed the optimal revascularisation mode (percutaneous coronary intervention [PCI] or coronary artery bypass grafting [CABG]) for each patient and made treatment recommendations. The primary endpoint of the trial was the level of agreement between the treatment recommendations of both teams as assessed using Cohen's kappa. RESULTS: The trial included 248 patients with MVD from 10 study sites. Cohen's kappa in the recommended revascularisation modes between the QFR and FFR approaches was 0.73 [95% confidence interval {CI} : 0.62-0.83]. As for the revascularisation planning, agreements in the target vessels for PCI and CABG were substantial for both revascularisation modes (Cohen's kappa=0.72 [95% CI: 0.66-0.78] and 0.72 [95% CI: 0.66-0.78], respectively). The team assigned to the QFR approach provided consistent recommended revascularisation modes even after being made aware of the FFR data (Cohen's kappa=0.95 [95% CI:0.90-1.00]). CONCLUSIONS: QFR provided feasible physiological data in Heart Team discussions to determine the optimal revascularisation strategy for MVD. The QFR and FFR approaches agreed substantially in terms of treatment recommendations.