Intermediate Luminosity Red Transients by Black Holes Born from Erupting Massive Stars

We consider black hole formation in failed supernovae when a dense circumstellar medium (CSM) is present around the massive star progenitor. By utilizing radiation hydrodynamical simulations, we calculate the mass ejection of blue supergiants and Wolf-Rayet stars in the collapsing phase and the radiative shock occurring between the ejecta and the ambient CSM. We find that the resultant emission is redder and dimmer than normal supernovae (bolometric luminosity of $\sim 10^{40}-10^{41}\ {\rm erg\ s^{-1}}$, effective temperature of $\sim 5\times 10^3$ K, and timescale of 10-100 days) and shows a characteristic power-law decay, which may comprise a fraction of intermediate luminosity red transients (ILRTs) including AT 2017be. In addition to searching for the progenitor star in the archival data, we encourage X-ray follow-up observations of such ILRTs $\sim$ 1-10 yr after the collapse, targeting the fallback accretion disk.Comment: 8 pages, 4 figures. Accepted for publication in ApJ letter

Diagnosis of Circumstellar Matter Structure in Type IIn Supernovae with Hydrogen Line Feature

Some supernovae (SNe), such as Type IIn SNe, are powered by collision of the SN ejecta with a dense circumstellar matter (CSM). Their emission spectra show characteristic line shapes of combined broad emission and narrow P-Cyg lines, which should closely relate to the CSM structure and the mass-loss mechanism that creates the dense CSM. We quantitatively investigate the relationship between the line shape and the CSM structure by Monte Carlo radiative transfer simulations, considering two representative cases of dense CSM formed by steady and eruptive mass loss. Comparing the H$\alpha$ emission between the two cases, we find that a narrow P-Cyg line appears in the eruptive case while it does not appear in the steady case, due to the difference in the velocity gradient in the dense CSM. We also reproduce the blue-shifted photon excess observed in some SNe IIn, which is formed by photon transport across the shock wave and find the relationship between the velocity of the shocked matter and the amount of the blue shift of the photon excess. We conclude that the presence or absence of narrow P-Cyg lines can distinguish the mass loss mechanism, and suggest high-resolution spectroscopic observations with $\lambda/ \Delta \lambda \gtrsim 10^4$ after the light curve peak for applying this diagnostic method.Comment: Submitted to Ap

737–1 Heart Fatty Acid-binding Protein and Myoglobin can Accurately Detect Successful Reperfusion as Early as 15 Minutes After Reperfuslon

Human heart fatty acid-binding protein (FABP) is an abundant low molecular weight protein in cytoplasm of myocardial cell similar to myoglobin (Mb). To evaluate whether FABP can also detect successful reperfusion very early like Mb, we examined serum FABP and Mb levels in 45 patients (pts) undergoing PTCR or PTCA within 6 hours after the onset of acute myocardial infarction. Coronary angiography was performed every 5minutes (min) during reperfusion therapy to determine the exact time of reperfusion. In 30 pts with reperfusion (reperfused group: TIMI grade 3 [23 pts] and grade 2 [7 pts]), serum samples were taken just before and at 15, 30 and 60min after initial angiographic confirmation of reperfusion. In 15 pts without reperfusion (nonreperfused group), serum samples were taken just before and at 15, 30 and 60min after the initiation of therapy. FABP was measured by competitive enzyme immunoassay and Mb by latex agglutination turbidimetry. The FABP ratio (FABP after/FABP before) and Mb ratio (Mb after/Mb before) were calculated. FABP and Mb levels increased rapidly, peaked within 60min after reperfusion. The FABP and Mb ratios in the reperfused group significantly (p<0.01) exceeded those in the nonreperfused group at 15, 30 and 60 min. The sensitivity (Sen) and specificity (Spe) of these markers for reperfusion were as follows:Criteria15 min30 min60 minSenSpeSenSpeSenSpeFABP ratio>1.6*93%100%97%100%100%100%Mb ratio>2.4**90%100%93%100%100%100%*mean +2SD at 60 min in the nonreperfused group**published criteriaConclusionFABP, like Mb could accurately detect successful reperfusion as early as 15min after reperfusion and could provide a high level of accuracy within 60min after reperfusion

Initial Surgical Versus Conservative Strategies in Patients With Asymptomatic Severe Aortic Stenosis

AbstractBackgroundCurrent guidelines generally recommend watchful waiting until symptoms emerge for aortic valve replacement (AVR) in asymptomatic patients with severe aortic stenosis (AS).ObjectivesThe study sought to compare the long-term outcomes of initial AVR versus conservative strategies following the diagnosis of asymptomatic severe AS.MethodsWe used data from a large multicenter registry enrolling 3,815 consecutive patients with severe AS (peak aortic jet velocity >4.0 m/s, or mean aortic pressure gradient >40 mm Hg, or aortic valve area <1.0 cm2) between January 2003 and December 2011. Among 1,808 asymptomatic patients, the initial AVR and conservative strategies were chosen in 291 patients, and 1,517 patients, respectively. Median follow-up was 1,361 days with 90% follow-up rate at 2 years. The propensity score–matched cohort of 582 patients (n = 291 in each group) was developed as the main analysis set for the current report.ResultsBaseline characteristics of the propensity score–matched cohort were largely comparable, except for the slightly younger age and the greater AS severity in the initial AVR group. In the conservative group, AVR was performed in 41% of patients during follow-up. The cumulative 5-year incidences of all-cause death and heart failure hospitalization were significantly lower in the initial AVR group than in the conservative group (15.4% vs. 26.4%, p = 0.009; 3.8% vs. 19.9%, p < 0.001, respectively).ConclusionsThe long-term outcome of asymptomatic patients with severe AS was dismal when managed conservatively in this real-world analysis and might be substantially improved by an initial AVR strategy. (Contemporary Outcomes After Surgery and Medical Treatment in Patients With Severe Aortic Stenosis Registry; UMIN000012140