Everolimus-eluting stents or bypass surgery for multivessel coronary disease

Copyright © 2015 Massachusetts Medical Society. BACKGROUND: Results of trials and registry studies have shown lower long-term mortality after coronary-artery bypass grafting (CABG) than after percutaneous coronary intervention (PCI) among patients with multivessel disease. These previous analyses did not evaluate PCI with second-generation drug-eluting stents. METHODS: In an observational registry study, we compared the outcomes in patients with multivessel disease who underwent CABG with the outcomes in those who underwent PCI with the use of everolimus-eluting stents. The primary outcome was all-cause mortality. Secondary outcomes were the rates of myocardial infarction, stroke, and repeat revascularization. Propensity-score matching was used to assemble a cohort of patients with similar baseline characteristics. RESULTS: Among 34,819 eligible patients, 9223 patients who underwent PCI with everolimus-eluting stents and 9223 who underwent CABG had similar propensity scores and were included in the analyses. At a mean follow-up of 2.9 years, PCI with everolimus-eluting stents, as compared with CABG, was associated with a similar risk of death (3.1% per year and 2.9% per year, respectively; hazard ratio, 1.04; 95% confidence interval [CI], 0.93 to 1.17; P = 0.50), higher risks of myocardial infarction (1.9% per year vs. 1.1% per year; hazard ratio, 1.51; 95% CI, 1.29 to 1.77; P<0.001) and repeat revascularization (7.2% per year vs. 3.1% per year; hazard ratio, 2.35; 95% CI, 2.14 to 2.58; P<0.001), and a lower risk of stroke (0.7% per year vs. 1.0% per year; hazard ratio, 0.62; 95% CI, 0.50 to 0.76; P<0.001). The higher risk of myocardial infarction with PCI than with CABG was not significant among patients with complete revascularization but was significant among those with incomplete revascularization (P = 0.02 for interaction). CONCLUSIONS: In a contemporary clinical-practice registry study, the risk of death associated with PCI with everolimus-eluting stents was similar to that associated with CABG. PCI was associated with a higher risk of myocardial infarction (among patients with incomplete revascularization) and repeat revascularization but a lower risk of stroke. (Funded by Abbott Vascular.)published_or_final_versio

Non-contact friction studied with pendulum AFM

Understanding nanoscale friction and dissipation is central to nanotechnology. The recent detection of the electronic friction drop caused by the onset of superconductivity in Nb by means of an ultrasensitive non-contact pendulum atomic force microscope (AFM) raised hopes that a wider variety of mechanical-dissipation mechanisms become accessible. In this thesis several mechanisms leading to the existence of non-contact friction at the nanoscale are studied and discussed. Chapters 2 and 3 concern the tool of choice, the pendulum AFM and the relevant forces and why it is a wonderful tool to investigate non-contact friction, chapter 4. The fundamental concepts of the experimental setup are discussed in chapter 5. Since the pendulum AFM is not a common tool in the research field and it is hardly discussed in literature, a detailed introduction of the working principal and sensing mechanism is given for the first time in chapter 6. Furthermore, the basic concepts are applied on a widely studied reference system, copper with sodium chloride, see chapter 7, where the non-contact friction behavior of a metal-insulator substrate is investigated. The result of this chapter show a distinguishable difference in the smooth rise of the non-contact friction due to the existence of an dielectric media on top of a metal, causing Joule dissipation. Moving on to more challenging system in the chapter 8, with a rather special electronic phase transition, the Charge Density Wave (CDW), observed in niobiumdiselenide NbSe2 below T = 34K. Here, we state for the first time the observation of discrete non-contact friction maxima multiplets. In collaboration with group of Prof. Dr. Erio Tosatti it was possible to find the theoretical explanation to the newly discovered non-contact friction mechanism. We observed hysteresis of the local 2 pi phase slips in the CDW phase order parameter, under the local influence of the tip potential. Furthermore, in the last chapter of the thesis, the preliminary results of niobium doped strontium titanate Nb : SrTiO3 (STO) are presented. We observed noncontact friction in the vicinity of the structural phase transition, which was theoretically proposed by Benassi et al., due to the softening of phononic modes at the structural anomaly, when the system becomes slow and soft. In addition, STO offers a second phase transition from the paraelectric state to the ferroelectric, and the random oriented electric dipoles become ordered and form domains in the XY plane. In this phase, we observed a remarkable train of non-contact friction maxima, which still lack a quantitative theoretical explanation. However, a possible candidate for the mechanism is briefly discussed. In summary, this thesis presents an overview over yet unknown mechanism of noncontact friction of matter, giving an adequate contribution to the understanding of dissipation processes of matter on the nanoscale

Nanoscale Friction of Ice

Friction between macroscopic surfaces sliding relative to each other has been long investigated, nevertheless it still remains one of the most complex and least understood processes in nature. In connection with the success in both experimental and theoretical fields, through the development of nanotribology offering the possibility of understanding atomic-level origins of friction, the subject continues to be re-examined. In this work we use molecular dynamics simulations to study frictional behavior of an ice-ice system (one of the most interesting systems from friction point of view due to its unusually low friction coefficient and prevalence in life) at the nanoscale, particularly the influence of temperature, applied load and sliding velocity on calculated frictional force. We compare our results to experimental findings and discuss agreement within different ranges of parameters affecting friction. Our work provides useful insight into the field of nanoscale ice friction and can be used as a basis for future development of the field

Are Sustainable Health Workforces Possible? Issues and a Possible Remedy

The 2020–2022 period of the global COVID-19 pandemic exposed the fact that many countries health systems had inadequate health workforce availability. This is despite sustainable health workforces being critical to health service and healthcare delivery, an acknowledgement that drove the significant investment and focus on health workforce development over the previous two decades. As such, this review article discusses health workforce governance and planning, notes its weaknesses, and identifies some of the barriers to the implementation of health workforce policy making and planning and the achievement of sustainable health workforces. Important is the recognition that health workforce planning is long-term in nature, while health workforce decision-making processes are dominated by political processes that have much shorter time frames. The article concludes by offering the approach of backcasting to overcome this dichotomy

Revascularization in patients with multivessel coronary artery disease and chronic kidney disease everolimus-eluting stents versus coronary artery bypass graft surgery

© 2015 American College of Cardiology Foundation. Background Randomized trials of percutaneous coronary intervention (PCI) versus coronary artery bypass graft (CABG) routinely exclude patients with chronic kidney disease (CKD). Objectives This study evaluated outcomes of PCI versus CABG in patients with CKD. Methods Patients with CKD who underwent PCI using everolimus-eluting stents were propensity-score matched to patients who underwent isolated CABG for multivessel coronary disease in New York. The primary outcome was all-cause mortality. Secondary outcomes were myocardial infarction (MI), stroke, and repeat revascularization. Results Of 11,305 patients with CKD, 5,920 patients were propensity-score matched. In the short term, PCI was associated with a lower risk of death (hazard ratio [HR]: 0.55; 95% confidence interval [CI]: 0.35 to 0.87), stroke (HR: 0.22; 95% CI: 0.12 to 0.42), and repeat revascularization (HR: 0.48; 95% CI: 0.23 to 0.98) compared with CABG. In the longer term, PCI was associated with a similar risk of death (HR: 1.07; 95% CI: 0.92 to 1.24), higher risk of MI (HR: 1.76; 95% CI: 1.40 to 2.23), a lower risk of stroke (HR: 0.56; 95% CI: 0.41 to 0.76), and a higher risk of repeat revascularization (HR: 2.42; 95% CI: 2.05 to 2.85). In the subgroup with complete revascularization with PCI, the increased risk of MI was no longer statistically significant (HR: 1.18; 95% CI: 0.67 to 2.09). In the 243 matched pairs of patients with end-stage renal disease on hemodialysis, PCI was associated with significantly higher risk of death (HR: 2.02; 95% CI: 1.40 to 2.93) and repeat revascularization (HR: 2.44; 95% CI: 1.50 to 3.96) compared with CABG. Conclusions In patients with CKD, CABG is associated with higher short-term risk of death, stroke, and repeat revascularization, whereas PCI with everolimus-eluting stents is associated with a higher long-term risk of repeat revascularization and perhaps MI, with no long-term mortality difference. In the subgroup on dialysis, the results favored CABG over PCI.Link_to_subscribed_fulltex

Complex reactions on a convertible catalyst surface: A study of the S-O-Cu system

The interaction of clean and partially oxidized Cu(110) with sulphur was studied by scanning tunneling microscopy and density functional theory calculations in the low-coverage range. On the clean Cu surface individual S atoms adsorb in the troughs between the Cu atom rows. Hollow sites are preferred, but long-bridge sites are occasionally occupied as well. The majority of adsorbed S, however, seems to be involved in the formation of highly mobile Cu S clusters of various sizes. The clusters preferentially attach to steps thus changing the step morphology completely. Some of the clusters form aggregates on the terraces. On the partially oxidized surface similar clusters form and cause long-range mass transport to steps. Additionally, nanowires form in [001] direction on and along the surface oxide stress domains. These nanowires have a complex composition, exhibit different corrugations and appear sometimes as three-dimensional needles. Occasionally they flip their direction by 90°, but doing so they partially decompose. Finally, annealing of the S-O-Cu surface leads to consumption of the surface oxide stripes indicating loss of oxygen presumably via SO formation. Simultaneously, linear sulphur chains suspended between the [001] –O-Cu-O- chains form in [11¯0] direction. The surprising multitude of processes and products even at low-pressure, low-temperature conditions in the comparatively simple S-O-Cu system highlights the difficulty of controlling reactivity and selectivity on such convertible catalyst surfaces. x y

Everolimus eluting stents versus coronary artery bypass graft surgery for patients with diabetes mellitus and multivessel disease

Background-In patients with diabetes mellitus and multivessel disease, coronary artery bypass graft surgery and percutaneous coronary intervention are treatment options. However, there is paucity of data comparing coronary artery bypass graft surgery against newer generation stents. Methods and Results-Patients included in the New York State registries who had diabetes mellitus and underwent isolated coronary artery bypass graft surgery or percutaneous coronary intervention with everolimus eluting stent (EES) for multivessel disease were included. Propensity score matching was used to assemble a cohort with similar baseline characteristics. The primary outcome was all-cause mortality. Secondary outcomes were myocardial infarction (MI), stroke, and repeat revascularization. Short-term (within 30 days) and long-term outcomes were evaluated. Among 16 089 patients with diabetes mellitus and multivessel disease, 8096 patients with similar propensity scores were included. At short-term, EES was associated with a lower risk of death (hazard ratio [HR] =0.58; 95% confidence interval [CI], 0.34-0.98; P=0.04) and stroke (HR=0.14; 95% CI, 0.06-0.30; P0.0001) but higher risk of MI (HR=2.44; 95% CI, 1.13-5.31; P=0.02). At long-term, EES was associated with a similar risk of death (425 [10.50%] versus 414 [10.23%] events; HR=1.12; 95% CI, 0.96-1.30; P=0.16), a lower risk of stroke (118 [2.92%] versus 157 [3.88%] events; HR=0.76; 95% CI, 0.58-0.99; P=0.04) but a higher risk of MI (260 [6.42%] versus 166 [4.10%] events; HR=1.64; 95% CI, 1.32-2.04; P0.0001) and repeat revascularization (889 [21.96%] versus 421 [10.40%] events; HR=2.42; 95% CI, 2.12-2.76; P0.0001). The higher risk of MI was not seen in the subgroup of EES patients who underwent complete revascularization (HR=1.37; 95% CI, 0.76-2.47; P=0.30). Conclusions-In patients with diabetes mellitus and multivessel disease, EES was associated with lower upfront risk of death and stroke when compared with coronary artery bypass graft surgery. However, at long-term, EES was associated with similar risk of death, a higher risk of MI (in those with incomplete revascularization), and repeat revascularization but a lower risk of stroke. © 2015 American Heart Association, Inc

Complex reactions on a convertible catalyst surface: A study of the S-O-Cu system

The interaction of clean and partially oxidized Cu(110) with sulphur was studied by scanning tunneling microscopy and density functional theory calculations in the low-coverage range. On the clean Cu surface individual S atoms adsorb in the troughs between the Cu atom rows. Hollow sites are preferred, but long-bridge sites are occasionally occupied as well. The majority of adsorbed S, however, seems to be involved in the formation of highly mobile CuxSy clusters of various sizes. The clusters preferentially attach to steps thus changing the step morphology completely. Some of the clusters form aggregates on the terraces. On the partially oxidized surface similar clusters form and cause long-range mass transport to steps. Additionally, nanowires form in [001] direction on and along the surface oxide stress domains. These nanowires have a complex composition, exhibit different corrugations and appear sometimes as three-dimensional needles. Occasionally they flip their direction by 90°, but doing so they partially decompose. Finally, annealing of the S-O-Cu surface leads to consumption of the surface oxide stripes indicating loss of oxygen presumably via SO2 formation. Simultaneously, linear sulphur chains suspended between the [001] –O-Cu-O- chains form in [11¯0] direction. The surprising multitude of processes and products even at low-pressure, low-temperature conditions in the comparatively simple S-O-Cu system highlights the difficulty of controlling reactivity and selectivity on such convertible catalyst surfaces