465Benefit of modern P2Y12-inhibitors on long-term prognosis in patients with ST-elevation myocardial infarction with and without advanced chronic kidney disease

Background

Current guidelines on the management of patients with ST-elevation myocardial infarction (STEMI) recommend the preferred use of the modern P2Y12-inhibitors ticagrelor or prasugrel regardless of the presence of chronic kidney disease (CKD), although patients with advanced stages of CKD were excluded from randomized trials. Aim of the present study was therefore to evaluate the potential benefit of modern P2Y12-inhibitors in patients with and without advanced renal disease at admission.

Methods

All patients admitted with STEMI between 2006–2017 from a large german heart center treated with primary percutaneous coronary intervention (PCI) entered analysis. Initial CKD was estimated with the initial glomerular filtration rate (GFR), calculated with the CKD-EPI-equation, assigning them to the groups G1-G5.

Results

Of 7227 patients with STEMI and primary PCI 2669 (37%) showed no relevant reduction in GFR at admission (≥90 ml/min/1.73 m2, G1), 2976 pts. (41%), a slight reduction (GFR 60–89 ml/min/1.73 m2, G2), 880 pts. (12%) a moderate reduction (GFR 45–59 ml/min/1.73 m2, G3a) and 702 pts. (10%) a moderate to severe reduction (GFR<45 ml/min 1.73 m2, G3b-G5). Pts. with more advanced stages of CKD were on average older (G1: 55±11 years, G2: 66±12 years, G3a: 72±12 years, G3b-G5: 75±11 years, p<0.01) and more likely to be female (G1: 19%, G2: 26%, G3a: 40%, G3b-G5: 48%, p<0.01). Prasugrel/ticagrelor were less often given instead of clopidogrel in patients with advanced CKD (G1: 70%, G2: 45%, G3a: 31%, G3b-G5: 32%, p<0.01). The use of ticagrelor/prasugrel was associated with a reduction in 1-year-MACCE (major adverse cardio- and cerebrovascular events)-rates in patients with no/low-grade-CKD (G1-G2), while no significant reduction in MACCE could be observed for patients with moderate to severe CKD (table). Furthermore, CKD was associated with an elevation in severe bleeding events within 1 year (G1: 1%, G2: 3%, G3a: 5%, G3b-G5: 6%, p<0.01).

Impact of CKD-stage on outcome CKD-stage G1 CKD-stage G2 CKD-stage G3a CKD-stage G3b-G5 1-year-MACCE-rate (%) Ticagrelor/prasugrel 4.5 11.0 27.4 47.3 Clopidogrel 9.9 15.6 26.6 50.4 Significance <0.01 <0.01 0.6 0.7

Conclusions

These data from a large STEMI-registry demonstrate, that modern P2Y12-inhibitors were less often used in patients with CKD and their benefit regarding MACCE disappeared in advanced stages of CKD while bleeding rates increased. These results underline the special role of patients with advanced stage-CKD in STEMI and the necessity of specialized randomized trials for these patients.

Design and implementation of a low temperature, inductance based high frequency alternating current susceptometer

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Chloride cotransporter KCC2 is essential for GABAergic inhibition in the SCN

One of the principal neurotransmitters of the central nervous system is GABA. In the adult brain, GABA is predominantly inhibitory, but there is growing evidence indicating that GABA can shift to excitatory action depending on environmental conditions. In the mammalian central circadian clock of the suprachiasmatic nucleus (SCN) GABAergic activity shifts from inhibition to excitation when animals are exposed to long day photoperiod. The polarity of the GABAergic response (inhibitory versus excitatory) depends on the GABA equilibrium potential determined by the intracellular Cl- concentration ([Cl-]i). Chloride homeostasis can be regulated by Cl- cotransporters like NKCC1 and KCC2 in the membrane, but the mechanisms for maintaining [Cl-]i are still under debate. This study investigates the role of KCC2 on GABA-induced Ca2+ transients in SCN neurons from mice exposed to different photoperiods. We show for the first time that blocking KCC2 with the newly developed blocker ML077 can cause a shift in the polarity of the GABAergic response. This will increase the amount of excitatory responses in SCN neurons and thus cause a shift in excitatory/inhibitory ratio. These results indicate that KCC2 is an essential component in regulating [Cl-]i and the equilibrium potential of Cl- and thereby determining the sign of the GABAergic response. Moreover, our data suggest a role for the Cl- cotransporters in the switch from inhibition to excitation observed under long day photoperiod.

Making Graphene Nanoribbons Photoluminescent

We demonstrate the alignment-preserving transfer of parallel graphene nanoribbons (GNRs) onto insulating substrates. The photophysics of such samples is characterized by polarized Raman and photoluminescence (PL) spectroscopies. The Raman scattered light and the PL are polarized along the GNR axis. The Raman cross section as a function of excitation energy has distinct excitonic peaks associated with transitions between the one-dimensional parabolic subbands. We find that the PL of GNRs is intrinsically low but can be strongly enhanced by blue laser irradiation in ambient conditions or hydrogenation in ultrahigh vacuum. These functionalization routes cause the formation of sp³ defects in GNRs. We demonstrate the laser writing of luminescent patterns in GNR films for maskless lithography by the controlled generation of defects. Our findings set the stage for further exploration of the optical properties of GNRs on insulating substrates and in device geometries.

Behaviour of the extractant Me-TODGA upon gamma irradiation: quantification of degradation compounds and individual influences on complexation and extraction

Understanding of ligand–metal interactions is crucial to develop new processes for nuclear waste treatment.

Effect of fibrous separators on the performance of lithium–sulfur batteries

In this paper we systematically investigated effect of separator morphology on the performance of Li–S batteries.