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With the vertical and horizontal expansion of urban underground space, there is an urgent need for the construction technology of underground building structures, and the application of underground diaphragm walls as basement support design is becoming more and more common. The application theory of the high-pressure rotary jetting pile as a water stop for the ground connection wall joint has great application potential in practical engineering. This paper analyzes the process principle, characteristics, process, operation points and economic and social benefits of the combined all-round high-pressure jetting pile construction technology, and demonstrates the advantages of this method in specific applications from multiple perspectives. The method adopts a three-axis mixing pile driver and a conventional omnidirectional high-pressure rotary jet pile equipment to form a new type of construction machine. It is a kind of micro-perturbation grouting construction technology, which can quickly penetrate the complex underground geology and avoid the impact of hole collapse on drilling. Strong controllability, can effectively protect the safety of surrounding buildings and municipal facilities.

In order to effectively solve the problems of high cracking risk, high safety risk, large construction period impact and high engineering cost of the basement roof of the scaffolding heavy-duty conversion platform, a construction method of heavy-duty conversion steel platform was proposed by referring to the force principle of the above-ground frame structure. The force mechanism, construction process, operation points and quality assurance measures of this method are clarified by theoretical analysis method combined with on-site engineering practice. Finally, the construction method of heavy-duty conversion steel platform is clarified by comparing with the traditional construction method of scaffolding support and reinforcement. The advantages. The research results show that the heavy-duty conversion steel platform mainly transfers the upper heavy lifting load to the steel beam through the subgrade box, and then transmits it to the pile foundation through the steel beam; It is green and environmentally friendly, and can effectively solve the quality and safety problems of underground structures. Compared with the traditional full-house scaffolding support and reinforcement construction method, the cost saving rate of the optimized heavy-duty conversion steel platform reinforcement method is about 12%, which is worthy of further promotion and application.

This work was to investigate TiO2 nanocrystalline film material in heart valve replacement (HVR) and the effect of papaverine infusion through the aortic root before cardiac self-recovery during the HVR. TiO2 nanocrystalline films were prepared by radio frequency (RF) reactive sputtering. The crystallization characteristics and surface morphology of TiO2 nanocrystalline films were observed by X-ray diffraction and scanning electron microscopy, and the anti-platelet adhesion and anti-coagulation properties of the films were analyzed. 86 patients with heart valve disease were selected and all underwent HVR. They were randomly divided into a control group (routine treatment) and an experimental group (papaverine perfusion through aortic root), with 43 cases in each group. The rate of cardiac self-recovery and the dosage of dopamine were observed. The results showed that the TiO2 nanocrystalline film was composed of a large number of uniform particles, and the average particle size was about 18.97 ± 7.28 nm. The rate of cardiac self-recovery in the experimental group was 97.67%, which was significantly higher than that in the control group (67.44%) (P0.05). The dosage of epinephrine, dopamine, and duration of cardiopulmonary bypass (CPB) assistance in the observation group were less than those in the control group (P0.05). These results indicated that TiO2 nanocrystalline film could be used in HVR, and papaverine infusion through aortic root before HVR and myocardial protection measures can significantly improve the rate of cardiac self-recovery and promote postoperative recovery.

Objective: To investigate the safety and efficacy of two-stage type II hybrid aortic arch repair (HAR) in elderly patients with acute type A aortic dissection (a-TAAD). Methods: This was a single-center, prospective study involved 119 patients with a-TAAD, included 82 males and 37 females, aged 22 ~81 years old. Eighty-eight patients underwent total aortic arch replacement (TAR) with stented frozen elephant trunk (FET) implantation (TAR with FET group) and 31 patients underwent two-stage type II HAR (HAR group). Propensity score matching (PSM) was applied to adjust for preoperative data, and 25 pairs were matched successfully. The preoperative, perioperative, postoperative and follow-up data in the HAR group and TAR with FET group were compared. Results: Fifteen patients died during the perioperative period; 13 cases were in the TAR with FET group and 2 cases were in the TAR group. The age, body mass index, cerebral infarction, renal insufficiency were significantly higher, and the 24-h fluid drainage, the incidence of acute liver injury, acute kidney injury and pulmonary infectionwere were lower in the HAR group. Moreover, the mechanical ventilation time, intensive care unit time, hospital stay timewere shorter in the HAR group.The follow-up period ranged from 12 to 54 months, with 7 deaths (9.3%) in the TAR with FET group and 2 deaths (6.9%) in the HAR group. The true lumen of the aortic arch (PConclusion: Two-stage type II HAR is a safe and effective method for elderly patients with a-TAAD. It may be a good choice for elderly patients with a-TAAD and comorbidities.

ObjectiveSystemic immune-inflammation index (SII) is a novel biomarker that can predict poor outcomes in tumours, nervous system diseases and chronic heart failure. Here, we investigated the predictive value of SII on the poor postoperative outcomes and short-term prognosis of heart valve diseases (HVDs).Design, setting and participantsThis retrospective cohort study enrolled all consecutive patients with HVDs (aortic stenosis, aortic regurgitation, mitral stenosis and mitral regurgitation) who underwent surgery (valve replacement or valve repair) at the Affiliated Hospital of North Sichuan Medical College between 2017 and 2020.Main outcomes and measuresMajor complications in the perioperative period, all-cause mortality within 30 days and readmission within 30 days.ResultsA total of 431 patients with HVDs were enrolled in this study, including 202 males and 229 females, aged 58.9±27.3 years. SII levels of patients in the poor outcomes group were significantly higher than those of patients in the favourable outcomes group (658.40±436.29 vs 335.72±174.76, respectively; p9 /L, with a sensitivity of 70.3% and specificity of 81.1%. The incidence of poor outcomes (pConclusionsSII is closely related to poor postoperative outcomes and short-term prognosis of HVD and can serve as an independent predictive factor.

Total anomalous pulmonary venous drainage (TAPVD) is caused by the absence of the congenital connection between the pulmonary vein and left atrium. This causes blood drainage into the right atrium, resulting in poor development of the left atrium and increasing the burden for the right atrium. It is accompanied by an atrial septal defect. TAPVD mostly is diagnosed during the fetal period and rarely is reported in adults. Atrial fibrillation (AF), a common arrhythmia, originates primarily from the joint of the pulmonary vein and left atrium, whereas AF originating from the right atrium has not been documented. Herein, we report the case of a 45-year-old male diagnosed with TAPVD accompanied by AF. After the correction of TAPVD and radiofrequency ablation (RFA) for AF performed under general anesthesia and cardiopulmonary bypass, the patient returned to normal sinus rhythm and showed no AF recurrence during two years of follow up.