The hazard ratio (0.676) (95% confidence interval 0.586-0.779; P<0.0001) for long-term survival was significantly in favour of TAR procedure. ...TAR should be strongly encouraged even revising the ...guidelines to emphasize the role of referral centers offering a high likelihood of TAR and low mortality in three-vessel coronary patients. * E-mail: francescoformica.hs@gmail.com Buttar SN, Yan TD, Taggart DP, Tian DH. Total arterial coronary bypass graft surgery is associated with better long-term survival in patients with multivessel coronary artery disease: a systematic review with meta-analysis.
In aged population, the early and long-term outcomes of coronary revascularization (CABG) added to surgical aortic valve replacement (SAVR) compared to isolated SAVR (i-SAVR) are conflicting. To ...address this limitation, a meta-analysis comparing the early and late outcomes of SAVR plus CABG with i-SAVR was performed. Electronic databases from January 2000 to November 2021 were screened. Studies reporting early-term and long-term comparison between the two treatments in patients over 75 years were analyzed. The primary endpoints were in-hospital/30-day mortality and overall long-term survival. The pooled odd ratio (OR) and hazard ratio (HR) with 95% confidence interval (CI) were calculated for in-early outcome and long-term survival, respectively. Random-effect model was used in all analyses. Forty-four retrospective observational studies reporting on 74,560 patients (i-SAVR = 36,062; SAVR + CABG = 38,498) were included for comparison. The pooled analysis revealed that i-SAVR was significantly associated with lower rate of early mortality compared to SAVR plus CABG (OR = 0.70, 95% CI 0.66–0.75;
p
< 0.0001) and with lower incidence of postoperative acute renal failure (OR = 0.65; 95% CI 0.50–0.91;
p
= 0.02), need for dialysis (OR = 0.65; 95% CI 0.50–0.86;
p
= 0.002) and prolonged mechanical ventilation (OR = 0.57; 95% CI 0.42–0.77;
p
< 0.0001). Twenty-two studies reported data of long-term follow-up. No differences were reported between the two groups in long-term survival (HR = 0.95; 95% CI 0.87–1.03;
p
= 0.23). CABG added to SAVR is associated with worse early outcomes in terms of early mortality, postoperative acute renal failure, and prolonged mechanical ventilation. Long-term survival was comparable between the two treatments.
Background. Long-term outcomes of patients with infective endocarditis (IE) who received either a mechanical (MP) or biological prosthesis (BP) are conflicting. A meta-analysis of observational ...studies comparing the long-term outcomes of left-side IE with the use of MP versus BP was performed. Methods. Electronic databases from January 2000 to June 2021 were screened. Studies reporting long-term mortality were analyzed. The primary endpoint was long-term overall mortality. Secondary endpoints were in-hospital/.30-day mortality and freedom from both prosthesis reinfection and reintervention. The pooled hazard ratio (HR) with 95% confidence interval (CI) was calculated for survival according to the random effect model. Results. Thirteen retrospective observational studies reporting on 8645 patients (MP: 4688; BP: 4137) were included for comparison. Twelve studies reported data of long-term survival for a total of 8285 patients (MP: 4517; BP: 3768). The pooled analysis revealed that the use of MP was statistically associated with longer benefits compared to BP (HR 0.74; 95% CI 0.63–0.86; p < 0.0001). The median follow-up time ranged from 1 to 15.3 years. The pooled analysis of five studies reporting data on prosthesis reinfection in 4491 patients (MP: 2433; BP: 2058) did not reveal significant differences (HR 0.60; 95% CI 0.30–1.21; p = 0.15). Five studies reported data on prosthesis reintervention in 4401 patients (MP: 2307; BP: 2094). The meta-analysis revealed a significant difference in favor of MP (HR 0.40; 95% CI 0.29–0.55; p < 0.0001). Meta-regression reported no effect of male gender (p = 0.09) and age (p = 0.77) on long-term survival. Conclusions. In a meta-analysis of retrospective observational studies comparing the long-term outcome of patients who underwent surgery for left-sided IE, the use of MP compared to BP is associated with a significant longer-term survival and with a reduced incidence of late reoperation. The incidence of late reinfection is comparable between the two prostheses.
In the fine chemical industry, a number of exothermic reaction processes are better performed under reflux conditions. Such an operating regime of the reactor allows for removing the reaction heat at ...a self-controlling temperature, hence preventing peaks of the conversion rate with their related thermal effects. Moreover, when the desired reaction generates a low volatility product, which can further react with a non-selective reactant, dosing such a reactant under reflux conditions potentially allows for removing the target species from the reactor, hence subtracting it from its further degradation. However, there exist also a number of processes that must be operated at temperature values lower than the normal boiling point of the low volatility product and for which vacuum conditions cannot be adopted, because of a number of process constraints. This prevents the possibility of taking advantage, from a safety point of view, of the aforementioned self-controlling feature of the processes operated under reflux conditions. The semibatch recycle reactor allows for achieving both a satisfactory process selectivity and productivity (strictly connected with the operating temperature range defined by the recipe) as well as the safer process conditions related to the reflux conditions thanks to its intrinsic possibility of operating even at atmospheric pressure the reaction vessel and the boiler at different temperature values.
In this work the general Ψ number criterion for the safe operation of semibatch runaway reactions has been applied to the optimization of a nitration process of primary importance in the agrochemical ...industry, that is the nitration through mixed acids of 4-chloro benzotrifluoride to produce a widely employed class of fluorinated herbicides. Such a reaction, as is the case for almost all the organic nitrations, belongs to the most critical class of exothermic reaction processes, for which the maximum temperature of the synthesis reaction under adiabatic conditions overcomes the decomposition temperature of the system, without any tempering effect due to a solvent evaporation. It has been verified that higher productivity operating conditions can be easily implemented through the general Ψ number criterion, even without a kinetic characterization of the system, but just elaborating information already available at the laboratory scale, where the chemical recipe is developed. The results obtained have been further validated through the boundary and temperature diagrams criterion, which however requires a previous estimation of the reaction kinetic parameters, with a much higher experimental effort.
Since the advent of TAVR (transcatheter aortic valve replacement), the transapical surgical approach has been affirmed as a safe and effective alternative access for patients with unsuitable ...peripheral arteries. With the improvement of devices for transfemoral approach and the development of other alternative accesses, the number of transapical procedures has decreased significantly worldwide. The left ventricular apex, however, has proved to be a safe and valid alternative access for various other structural heart procedures such as mitral valve repair, mitral valve-in-valve or valve-in-ring replacement, transcatheter mitral valve replacement (TMVR), transcatheter mitral paravalvular leak repair, and thoracic aorta endovascular repair (TEVAR). We review the literature and our experience of various hybrid transcatheter structural heart procedures using the transapical surgical approach and discuss pros and cons.
On computed tomography (CT) imaging, a peri-vascular adipose tissue attenuation (pVAT) measure has been proposed as a non-invasive correlate of inflammation in the coronary artery vessels, and a ...single research group provided histopathological demonstration of this radiological/pathological correspondence. Our group has shown that patients with surgical-grade ascending aorta (AA) aneurysm display higher pVAT compared with patients with smaller aneurysms or normal AA. Based on histopathological studies on coronary arteries, we speculated that this correlation may be related to a non-otherwise specified aortic inflammatory process. However, since adipose tissue around the AA is often scant, and there are no histopathological studies confirming such hypothesized association between higher pVAT and inflammation around the AA, we cannot exclude that this pVAT change is secondary to different mechanisms, unrelated to the actual presence of peri-vascular inflammation. We performed a retrospective clinical/radiological/pathological study in 78 patients who underwent AA surgery with the aim to correlate pre-operatory pVAT on CT with histopathological findings from the surgical specimens. Histopathological review and immunohistochemistry were performed on the surgical aortic samples. The AA adventitial/periadventitial adipose tissue had higher pVAT by an increasing collagen fiber deposition, which progressively makes the fat hypotrophic and, in the late stages of this process, it replaces the normal soft tissue composition in this location. In the ascending aorta, pVAT on CT imaging is probably not a proxy for the presence of current vascular inflammation, although it may track changes involving the progressive substitution of perivascular adipose cells by higher-pVAT tissues, mainly fibrotic replacement.
In this work, a simple and general method has been developed that, on the basis of an easy-to-measure quantity referred to as the Ψ number, allows for ongoing detection of the displacement of the SBR ...operating regime from safe target conditions, without any information about the reaction kinetics. Such a feature is of particular importance because, when dealing with reaction processes in the fine-chemicals and pharmaceuticals industries, the estimation of the kinetic parameters of the reactions involved is often not practicable, because of the huge variety of productions encountered and the simultaneous occurrence of mass-transfer phenomena in heterogeneous systems. Moreover, the method in question has been confirmed to be useful for the early detection of low-reactivity or non-ignition regimes of the SBR, to prevent the dangerous accumulation phenomena resulting in a thermal loss of control of the main reaction and a further triggering of pressure-generating decomposition events. Finally, the criterion was validated by analyzing the available data from an industrial SBR in which the water emulsion polymerization of acrylic monomers was performed.
A number of potential runaway reaction systems of the fine chemical industry (e.g., polymerization processes) undergo significant changes of their physical properties with the reaction extent, ...resulting in thickening phenomena of the reaction mass and in a consequent decay of the reactor heat-transfer efficiency. In this work, a set of key process indicators have been developed, allowing for monitoring of safe operating conditions of industrial semibatch polymerization reactors without requiring any kinetic characterization of the reaction system. The only required information are the heat of reaction and some fully available process variables that are normally recorded for any industrial reactor. The proposed criterion has been successfully validated using some experimental data measured on an industrial polymerization reactor for the production of polyacrylic rheology modifiers.
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