Abstract Objectives This study used a fractal bifurcation bench model to compare 6 optimization sequences for coronary bifurcation provisional stenting, including 1 novel sequence without kissing ...balloon inflation (KBI), comprising initial proximal optimizing technique (POT) + side-branch inflation (SBI) + final POT, called “re-POT.” Background In provisional bifurcation stenting, KBI fails to improve the rate of major adverse cardiac events. Proximal geometric deformation increases the rate of in-stent restenosis and target lesion revascularization. Methods A bifurcation bench model was used to compare KBI alone, KBI after POT, KBI with asymmetric inflation pressure after POT, and 2 sequences without KBI: initial POT plus SBI, and initial POT plus SBI with final POT (called “re-POT”). For each protocol, 5 stents were tested using 2 different drug-eluting stent designs: that is, a total of 60 tests. Results Compared with the classic KBI-only sequence and those associating POT with modified KBI, the re-POT sequence gave significantly (p < 0.05) better geometric results: it reduced SB ostium stent-strut obstruction from 23.2 ± 6.0% to 5.6 ± 8.3%, provided perfect proximal stent apposition with almost perfect circularity (ellipticity index reduced from 1.23 ± 0.02 to 1.04 ± 0.01), reduced proximal area overstretch from 24.2 ± 7.6% to 8.0 ± 0.4%, and reduced global strut malapposition from 40 ± 6.2% to 2.6 ± 1.4%. Conclusions In comparison with 5 other techniques, the re-POT sequence significantly optimized the final result of provisional coronary bifurcation stenting, maintaining circular geometry while significantly reducing SB ostium strut obstruction and global strut malapposition. These experimental findings confirm that provisional stenting may be optimized more effectively without KBI using re-POT.
Summary Background As current multidetector computed tomography (MDCT) measurements underestimate the size of the aortic annulus ahead of transcatheter aortic valve implantation (TAVI), a strategy of ...approximate annulus area oversizing has been adopted recently. Aims To measure the aortic annulus using a novel complementary intravalvular MDCT slice. Methods Fifty-five patients with severe aortic stenosis were selected for MDCT ahead of and 1 month after CoreValve® TAVI. Two MDCT slices were analysed and compared: the current standard virtual basal ring (VBR) at the nadir of the aortic cusps; and a novel slice, defined as the basal (lowest) complete commissural coaptation (BCCC) plane. Results BCCC is an intravalvular plane lying 5.2 ± 0.8 mm above the VBR. The BCCC annulus is almost circular, unlike the VBR (mean eccentricity index 0.09 ± 0.04 vs 0.3 ± 0.1, respectively). The mean BCCC annulus diameter was 26.6 ± 2.3 mm, 16% larger than that of the VBR (23.9 ± 2.2 mm; P < 0.001). The BCCC annulus area proved coherent with the orifice area measured after TAVI on the projection of the same slice (i.e. systematically equal to or greater than the latter mean difference, +2.3 ± 1.4 mm), in contrast to the wider scatter found for the VBR (–1.3 ± 2.0 mm). Once the sclerotic calcified valves have been pushed back by the implant, the aortic orifice after TAVI will inevitably be equal to or less than the diameter of the virtually unvalved annulus before TAVI. Conclusion Based on the present results, we recommend including a BCCC slice to complete aortic annulus sizing, in order to optimize implant calibration.
Abstract Objectives The aim of this fractal bifurcation bench study was to compare provisional bifurcation stenting with a “re-POT” sequence, comprising a proximal optimizing technique (POT), side ...branch inflation, and final POT, between a bioresorbable vascular scaffold (BVS) and a metallic stent. Background Re-POT proved significantly better than kissing balloon inflation in maintaining circular geometry without overstretch in metal stents, while significantly reducing side branch ostium strut obstruction and global strut malapposition. This should be useful for BVSs, which are more easily breakable. Methods Twenty left main–like and 20 left anterior descending–like fractal coronary bifurcation bench models used 10 each 2.5 × 24 mm and 3.5 × 24 mm Absorb (Ab) BVSs and 10 each 2.5 × 24 mm and 3.5 × 24 mm XIENCE Xpedition (XX) metal stents, implanted by re-POT, with optical coherence tomographic analysis at each step and micro–computed tomographic analysis of Ab devices to detect strut fracture. Results With Ab devices, re-POT reduced percentage strut malapposition close to XX rates (0.8 ± 0.7% vs. 0.0 ± 0.0%, p < 0.05; 3.5 ± 1.7% vs. 0.3 ± 0.6%, p < 0.05), conserving proximal circularity (elliptical ratio, 1.04 vs. 1.03 and 1.04 vs. 1.04; p = NS). Mean post-re-POT proximal expansion was 0.6 ± 0.1 mm (+21.6 ± 2.1%) for 2.5-mm and 1.0 ± 0.1 mm (+23.6 ± 2.2%) for 3.5-mm Ab devices, with only 1 strut fracture (left anterior descending–like bench). Side branch ostium strut obstruction was greater with Ab scaffolds than XX stents: 41.1 ± 9.4% versus 16.4 ± 8.1% (p < 0.05) and 31.8 ± 3.2% versus 10.0 ± 5.3% (p < 0.05), respectively, for 2.5- and 3.5-mm scaffolds and stents. Ab scaffolds showed 2 ± 1% moderate but significant late recoil as of 1 h, reaching 4 ± 2% by 24 h (p < 0.05). Conclusions Re-POT optimized most Ab provisional bifurcation treatments, without fracture, respecting fractal geometry, and without exceeding 1.0-mm proximal differential diameter.
Despite significant progress, malapposed or overlapped stents are a complication that affects daily percutaneous coronary intervention (PCI) procedures. These malapposed stents affect blood flow and ...create a micro re-circulatory environment. These disturbances are often associated with a change in Wall Shear Stress (WSS), Time-averaged WSS (TAWSS), relative residence time (RRT) and oscillatory character of WSS and disrupt the delicate balance of vascular biology, providing a possible source of thrombosis and restenosis. In this study, 2D axisymmetric parametric computational fluid dynamics (CFD) simulations were performed to systematically analyze the hemodynamic effects of malapposition and stent overlap for two types of stents (drug-eluting stent and a bioresorbable stent). The results of the modeling are mainly analyzed using streamlines, TAWSS, oscillatory shear index (OSI) and RRT. The risks of restenosis and thrombus are evaluated according to commonly accepted thresholds for TAWSS and OSI. The small malapposition distances (MD) cause both low TAWSS and high OSI, which are potential adverse outcomes. The region of low OSI decrease with MD. Overlap configurations produce areas with low WSS and high OSI. The affected lengths are relatively insensitive to the overlap distance. The effects of strut size are even more sensitive and adverse for overlap configurations compared to a well-applied stent.
The aim of this study was to ascertain whether a minimalist immediate mechanical intervention (MIMI) aiming to restore an optimal Thrombolysis In Myocardial Infarction (TIMI) flow in the culprit ...artery, followed ≥7 days later by a second percutaneous coronary intervention with intentional stenting, is safe in patients with ST-segment elevation myocardial infarction and large thrombotic burden.
SUPER-MIMI was a prospective, observational trial conducted between January 2014 and April 2015 in 14 French centres. A total of 155 patients were enrolled. The pharmacological therapy was left to the operator's discretion. Eighty-one patients (52.3%) had glycoprotein IIb/IIIa inhibitors (GPI) initiated before the end of the first procedure. The median (interquartile range IQR) delay between the two procedures was eight (seven to 12) days. Infarct-related artery reocclusion between the two procedures (primary endpoint) occurred in two patients (1.3%), neither of whom received GPI treatment. TIMI flow was maintained or improved between the end of the first procedure and the beginning of the second procedure in all patients. Thrombotic burden and stenosis severity diminished significantly between the two procedures. Stents were ultimately implanted in 97 patients (62.6%).
Deferred stenting (≥7 days) in patients with a high thrombus burden was safe on a background of GPI therapy.
On univariate analysis, factors for elevated PASP were female sex, history of myocardial infarction, pacemaker implantation and permanent pacing, atrial fibrillation and degree of mitral ...regurgitation.
BackgroundHaving conquered water surfaces worldwide, the semi-aquatic bugs occupy ponds, streams, lakes, mangroves, and even open oceans. The diversity of this group has inspired a range of ...scientific studies from ecology and evolution to developmental genetics and hydrodynamics of fluid locomotion. However, the lack of a representative water strider genome hinders our ability to more thoroughly investigate the molecular mechanisms underlying the processes of adaptation and diversification within this group.ResultsHere we report the sequencing and manual annotation of the Gerris buenoi (G. buenoi) genome; the first water strider genome to be sequenced thus far. The size of the G. buenoi genome is approximately 1,000 Mb, and this sequencing effort has recovered 20,949 predicted protein-coding genes. Manual annotation uncovered a number of local (tandem and proximal) gene duplications and expansions of gene families known for their importance in a variety of processes associated with morphological and physiological adaptations to a water surface lifestyle. These expansions may affect key processes associated with growth, vision, desiccation resistance, detoxification, olfaction and epigenetic regulation. Strikingly, the G. buenoi genome contains three insulin receptors, suggesting key changes in the rewiring and function of the insulin pathway. Other genomic changes affecting with opsin genes may be associated with wavelength sensitivity shifts in opsins, which is likely to be key in facilitating specific adaptations in vision for diverse water habitats.ConclusionsOur findings suggest that local gene duplications might have played an important role during the evolution of water striders. Along with these findings, the sequencing of the G. buenoi genome now provides us the opportunity to pursue exciting research opportunities to further understand the genomic underpinnings of traits associated with the extreme body plan and life history of water striders.
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