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The formation of nano-sized, coherent, solute-rich clusters (NSRC) is known to be an important factor causing the degradation of the macroscopic properties of steels under irradiation. The mechanisms driving their formation are still debated. This work focuses on low-Cu reactor pressure vessel (RPV) steels, where solute species are generally not expected to precipitate. We rationalize the processes that take place at the nanometer scale under irradiation, relying on the latest theoretical and experimental evidence on atomic-level diffusion and transport processes. These are compiled in a new model, based on the object kinetic Monte Carlo (OKMC) technique. We evaluate the relevance of the underlying physical assumptions by applying the model to a large variety of irradiation experiments. Our model predictions are compared with new experimental data obtained with atom probe tomography and small angle neutron scattering, complemented with information from the literature. The results of this study reveal that the role of immobilized self-interstitial atoms (SIA) loops dominates the nucleation process of NSRC.

Early and long-term outcomes in elderly patients who underwent isolated aortic valve replacement (iAVR) are well defined. Conflicting data exist in elderly patients who underwent AVR plus coronary artery bypass grafting (CABG). We sought to evaluate the early and long-term outcomes of combined AVR + CABG in patients older than 75 years of age. From June 1999 to June 2018, 402 patients ≥ 75 years who underwent iAVR (n = 200; 49.7%) or combined AVR plus CABG (n = 202; 50.3%) were retrospectively analysed. AVR + CABG patients were older than iAVR patients (78.5 ± 2.5 vs 77.6 ± 2.8 years; p < 0.0001), with greater co-morbidities and more urgent/emergency surgery. 30-day mortality was 6.5% in the AVR + CABG and 4.5% in the iAVR group (p = 0.38). Multivariate analysis identified EuroSCORE II [odd ratio (OR) 1.13] postoperative stroke (OR 12.53), postoperative low cardiac output syndrome (OR 8.72) and postoperative mechanical ventilation > 48 h (OR 8.92) as independent predictors of 30-day mortality; preoperative cerebrovascular events (OR 3.43), creatinine (OR 7.27) and extracorporeal circulation time (OR 1.01) were independent predictors of in-hospital major adverse cardiovascular and cerebral events (MACCE). Treatment was not an independent predictor of 30-day mortality and in-hospital MACCE. Survival at 1, 5 and 10 years was 94.7 ± 1.6%, 72.6 ± 3.6% and 31.7 ± 4.8% for iAVR patients and 89.1 ± 2.3%, 73.9 ± 3.5% and 37.2 ± 4.8% for AVR + CABG subjects (p = 0.99). Using adjusted Cox regression model, creatinine [hazard ration (HR) 1.50; p = 0.018], COPD (HR 1.97; p = 0.003) and NYHA class (HR 1.39; p < 0.0001) were independent predictors of late mortality; the combined AVR + CABG was not associated with increased risk of late mortality (HR 0.83; p = 0.30). In patients aged ≥ 75 years, combined AVR + CABG was not associated with increased 30-day mortality, in-hospital MACCE and long-term mortality. Surgical revascularization can be s

Background: Long-term survival benefits of full arterial revascularization with radial artery (RA) used in addition to bilateral internal mammary arteries (BIMA) compared with saphenous vein (SV) used in addition to BIMA has not been clearly defined. Methods: We retrospectively analyzed 660 3-vessel coronary artery disease subjects who received BIMA in addition to either RA (n = 206) or SV (n = 454) grafting in a period between June 1999 and November 2017. After propensity score matching, we obtained 190 matched pairs for analysis. Results: In the matched population, in-hospital mortality occurred in 4 patients (1%), with 2 deaths (1.1%) in the BIMA + RA group and 2 deaths (1.1%) in BIMA + SV group (P >.99). The median follow-up time was 9.2 years (interquartile range, 5.6-13 years) with a maximum follow-up time of 18.5 years. There was not a significant difference in long-term survival between the 2 groups over the follow-up period. Survival at 5, 10, and 15 years were 94.8 ± 1.7%, 83.7 ± 3.1%, and 78.6 ± 3.9% in the BIMA + RA group and 96.2 ± 1.4%, 85.1 ± 2.9%, and 80.4 ± 3.6% in the BIMA + SV group (stratified log-rank P =.78). Cox proportional hazard regression model was used to estimate that the use of RA in addition to BIMA did not affect the late mortality (propensity score adjusted hazard ratio, 1.05; 95% confidence interval, 0.62-1.79; P =.83). Conclusions: In a relatively small population of triple-vessel coronary artery disease, the use of RA as a third arterial conduit with BIMA did not confer a long-term survival benefit.

OBJECTIVES: Left ventricular free wall rupture (LVFWR) is a catastrophic complication following acute myocardial infarction with an estimated incidence of 0.2–7.6% and mortality can be as high as 60%. This study aimed to identify the risk factors for morbidity and mortality in patients affected by LVFWR. METHODS: This is a retrospective study of 35 patients who underwent surgery for LVFWR between January 2000 and December 2016 at our institution. RESULTS: The mean age of patients was 68.3 years. The in-hospital survival was 65.7% (n = 23), and 13% of survived patients presented with cardiac arrest. The following characteristics were associated with in-hospital mortality at univariable analysis: pre-existing hypertension (P = 0.02), need for inotropes (P = 0.02) and cardiac arrest (P < 0.0001) at presentation, cardiopulmonary resuscitation (P = 0.004), preoperative extracorporeal membrane oxygenation (P = 0.004), technique of LVFWR repair (P = 0.013), operation on extracorporeal membrane oxygenation (P = 0.005) and postoperative extracorporeal membrane oxygenation (P = 0.001). In the multivariable analysis, cardiac arrest at presentation was an independent predictor of in-hospital mortality (odds ratio 11.7, 95% confidence interval 2.352–59.063; P = 0.003). The overall mean postoperative follow-up was 8.3 ± 1.3 years. Overall survival rates at 5 and 10 years were 53.2 ± 8.6% and 49.1 ± 8.9%, respectively. Among the survivors, only 6 (26.1%) patients died during follow-up with a 5-year and 10-year overall survival rate of 80.9 ± 8.7% and 74.7 ± 10%, respectively. CONCLUSIONS: These data suggest a trend towards long-term benefit in patients surviving high-risk surgery for LVFWR repair. Considering the high lethality of LVFWR, the urgency and complexity of the primary surgical intervention early diagnosis and prompt surgery play a key role in the management of this complication