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Introduction: Chronic severe aortic regurgitation (AR) has a poor long-term prognosis, especially among old-age patients. Considering their advancing age, the surgical approach of aortic valve replacement may not always be the best alternative modality of treatment in such patients. Therefore, this study's primary goal was to provide an initial summary of the medium- and short-term clinical effectiveness of transcatheter aortic valve replacement (TAVR) guided by accurate multi-detector computed tomography (MDCT) measurements in patients with severe and chronic AR, especially in elderly patients. Methods: The study enrolled retrospectively and prospectively patients diagnosed with severe AR who eventually underwent TAVR procedure from January 2019 to September 2022 at Fuwai cardiovascular Hospital, Beijing. Baseline information, MDCT measurements, anatomical classification, perioperative, and 1-year follow-up outcomes were collected and analyzed. Based on a novel anatomical categorization and dual anchoring theory, patients were divided into four categories according to the level of anchoring area. Type 1, 2, and 3 patients (with at least two anchoring regions) will receive TAVR with a transcatheter heart valve (THV), but Type 4 patients (with zero or one anchoring location) will be deemed unsuitable for TAVR and will instead receive medical care (retrospectively enrolled patients who already underwent TAVR are an exception). Results: The mean age of the 37 patients with severe chronic AR was 73.1 ± 8.7 years, and 23 patients (62.2%) were male. The American Association of Thoracic Surgeons' score was 8.6 ± 2.1%. The MDCT anatomical classification included 17 cases of type 1 (45.9%), 3 cases of type 2 (8.1%), 13 cases of type 3 (35.1%), and 4 cases of Type 4 (10.8%). The VitaFlow valve (MicroPort, Shanghai, China) was implanted in 19 patients (51.3%), while the Venus A valve (Venus MedTech, Hangzhou, China) was implanted in 18 patients (48.6%). Immediate TAVR procedural and device success rates were 86.5% and 67.6%, respectively, while eight cases (21.6%) required THV-in-THV implantation, and nine cases (24.3%) required permanent pacemaker implantation. Univariate regression analysis revealed that the major factors affecting TAVR device failure were sinotubular junction diameter, THV type, and MDCT anatomical classification (p < 0.05). Compared with the baseline, the left ventricular ejection fraction gradually increased, while the left ventricular end-diastolic diameter remained small, and the N-terminal-pro hormone B-type natriuretic peptide level significantly decreased within one year. Conclusion: According to the results of our study, TAVR with a self-expanding THV is safe and feasible for patients with chronic severe AR, particularly for those who meet the criteria for the appropriate MDCT anatomical classification with intact dual aortic anchors, and it has a significant clinical effect for at least a year. [ABSTRACT FROM AUTHOR]

Summary: This paper presents the work on the structural health monitoring design and operational modal analysis of a 250‐m super‐tall building situated in Shanghai, China. The building is a steel–concrete composite structure with a steel composite frame‐concrete core tube system. At the 21st and 36th–38th floors, outrigger trusses and ring‐shaped trusses are set to strengthen this structure. Because the height of this structure is overlimited and its lateral stiffness in the vertical direction is nonuniform, a SHM system was designed to monitor the structural condition and evaluate its safety. The SHM system is presented in this paper, and the instrumented equipment includes accelerometers and tilt sensors. The locations of sensors were well arranged so that SHM could be conducted using the least amount of sensors. On the basis of the system, an ambient vibration test was carried out to perform the analysis with four setups designed to investigate the modal parameters in the X and Y directions. The Fast Bayesian FFT method was employed to perform the operational modal analysis. The first 10 modes were identified. The modal parameters obtained by the Bayesian method are studied and discussed, and they are compared with the results obtained by other methods. Long‐term monitoring of this super‐tall building was also carried out to investigate the change of modal parameters in different stages. The results of this study are expected to provide a reference for model updating, damage detection, and SHM of this high‐rise building. [ABSTRACT FROM AUTHOR]

• Modal properties of the Shanghai Tower are identified by performing vibration test. • A simplified FE model for quick assessment of super tall buildings is developed. • Model updating is successfully conducted on the developed FE model for the tower. • Seismic response of the tower is evaluated by dynamic analysis of the updated model. The Shanghai Tower is presently the tallest structure in China and one of the super tall buildings in the world. To get a quick and direct insight into the overall dynamic behavior of this complex structure, a lumped-mass finite element model based on macro beam theory was developed. Next, an in-depth sensitivity analysis was performed on this baseline model and model updating was conducted by using modal properties obtained from a full-scale field test of this building in its final stage of construction. The difference of the first nine frequencies was reduced from 27% to 4% after updating, and modal assurance criterion value was improved from 73% to 87%. Time history analyses under two severe seismic events were conducted on both the baseline and updated models. The maximum story drift from the updated model were 40% higher than that from the baseline model, demonstrating the significant influence of model updating on its seismic performance. The framework of model updating by simplified updated model for super tall buildings described in this study provides an efficient way to predict their seismic responses, and the outputs are reliable for wide range of applications in the area of long-term heath monitoring and seismic retrofit. [ABSTRACT FROM AUTHOR]