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Objectives We evaluated the safety and usefulness of preparatory anatomical reshaping with a geometric hourglass-shaped balloon to optimize transcatheter aortic valve replacement (TAVR) outcomes in bicuspid aortic valve (BAV) stenosis. Background TAVR has been increasingly performed for BAV stenosis; however, technical challenges remain. Procedural results are suboptimal given unfavorable valvular anatomies. Methods Eligible patients with BAV stenosis were enrolled to undergo aortic valve predilatation with the hourglass-shaped TAV8 balloon before TAVR using the self-expandable Venus A-Valve. Procedural details and outcomes were compared to a sequential group of patients with BAV who underwent TAVR with the same device following preparatory dilatation using a cylindrical balloon. Results A total of 22 patients were enrolled in the TAV8 group and 53 were included in the control group. Valve downsizing was less common in the TAV8 group (36.4 vs. 67.9%; p = .012). Stable valve release and optimal implant depth were consistently achieved in the TAV8 group with no requirement for a second valve (0 vs. 17.0%; p = .039) and with higher device success rates (100.0 vs 77.4%; p = .014). Residual aortic regurgitation graded as ≥mild was less common in the TAV8 group (13.6 vs 45.3%; p = .009). Mortality was similar (0 vs. 3.8%; p = 1); no major/disabling stroke or conversion to open-heart surgery was seen in either group within 30 days. Conclusions Compared with standard cylindrical balloon valvuloplasty, preparatory reshaping with the hourglass-shaped balloon before self-expandable TAVR in BAV was associated with significantly better procedural results and may encourage more promising outcomes.

Background Studies of permanent pacemaker implantation (PPI) after transcatheter aortic valve replacement (TAVR) specifically for bicuspid aortic valve (BAV) patients are lacking. We aim to delineate possible aspects that might affect the incidence of PPI in a retrospective cohort of BAV patients treated with early-generation self-expanding devices. Methods A total of 80 patients with bicuspid morphology who successfully underwent TAVR by self-expanding devices without prior PPI were included. Baseline clinical, echocardiographic, and angiographic characteristics, procedural and post-procedural details were collected. Results The incidence of PPI after early-generation self-expanding valves in this BAV cohort was 26.3%. Baseline characteristics were comparable between patients requiring PPI post-TAVR or not. Perimeter oversizing greater than 20% significantly increased the risk of PPI compared with an oversizing of 10-20% (OR 5.08 [1.22, 21.07], P = 0.03). The proportion of patients with a depth of implantation greater than 6 mm was significantly higher in those who required PPI (82.4% vs 54.3%, P = 0.04). When testing the impact of depth of implantation >6 mm and oversizing in different morphologies, only in type 1 bicuspid patients and by oversizing>20% increased the risk of PPI (OR 12.00 [1.25, 115.36], P = 0.03) compared with an oversizing of 10-20%. Conclusions Excessive perimeter oversizing in relation to aortic annulus and depth of implantation greater than 6 mm should be avoided to improve PPI post-TAVR for BAV patients receiving self-expanding devices, especially for type 1 BAV.

Background Transcatheter aortic valve implantation (TAVI) has been demonstrated to be an effective alternative to surgical aortic valve replacement (SAVR) in patients with aortic stenosis who are deemed high risk or inoperable. Currently, TAVI procedures in China mostly make use of the domestic Venus A-Valve and the CoreValve; however, there is no data on their comparative performance. Methods Consecutive patients undergoing TAVI with the aforementioned devices were included. The outcomes were reported according to the Valve Academic Research Consortium-2 (VARC) definitions. Results A total of 54 TAVI procedures were performed, 27 with the CoreValve and the other 27 with the Venus A-Valve. An additional valve was required in 4 (14.8%) and 3 (11.1%) patients, and the VARC-2 device success rates were 81.5 and 85.2%, respectively. The incidences of common complications were similar, except for the significantly less frequent pacemaker insertion in the Venus A-Valve group (7.4 vs. 37.0%, P = 0.03). Within 30 days, 2 (3.7%) patients died, 1 in each group, and both had a bicuspid aortic valve (BAV). No other serious complications, such as annular rupture, coronary obstruction and aortic dissection, occurred in the 32 BAV patients treated with the Venus A-Valve (14) or the CoreValve (18). After 2-years of follow-up, there was no significant difference between CoreValve group and Venus-A group (11.1 vs. 7.4%, P = 0.64). Conclusion TAVI with the domestic Venus A-Valve is feasible, safe, and can produce favorable short-term outcomes comparable to those with the CoreValve in inoperable or high-risk patients with tricuspid and bicuspid aortic valve stenosis. © 2017 Wiley Periodicals, Inc.

Background The Global Registry of Acute Coronary Events (GRACE) risk score has been extensively validated to predict risk during hospitalization in patients with acute coronary syndrome (ACS). Recently, serum calcium has been suggested as an independent predictor for in-hospital mortality in patients with ST-segment elevation myocardial infarction; however, the relationship between the 2 has not been evaluated. Hypothesis The combination of GRACE risk score and serum calcium could provide better performance in risk prediction. Methods The study enrolled 2229 consecutive patients with ACS. Independent predictors were identified by a multivariate logistic regression model. The incremental prognostic value added by serum calcium to the GRACE score was evaluated by receiver operating characteristic, net reclassification improvement (NRI), and integrated discrimination improvement (IDI). Results Patients in the upper quartiles of serum calcium presented with lower in-hospital mortality (odds ratios for 3 upper quartiles vs lowest quartile, respectively: 0.443, 95% confidence interval [CI]: 0.206-0.953; 0.243, 95% CI: 0.090-0.654; and 0.210, 95% CI: 0.082-0.538). Area under the curve increased significantly after adding serum calcium to the GRACE score (0.685 vs 0.746; Z = 2.617, P = 0.009). Furthermore, inclusion of serum calcium in the GRACE score enhanced NRI (0.524; P = 0.009) and IDI (0.011; P = 0.003). Conclusions Lower serum calcium level on admission is a possible indicator of increased risk of in-hospital mortality in ACS patients. Inclusion of serum calcium in the GRACE score may lead to a more accurate prediction of this risk. Large prospective studies are needed to confirm this finding.

Background Changes in the ECG indicator PtfV1 reflect left atrial pressure and left ventricular diastolic function in NSTE-ACS patients during hospitalization. The value of PtfV1 in the evaluation of long-term prognosis in NSTE-ACS is still not clear. The purpose of this study was to investigate the relationship between the dynamic changes in P-wave terminal force in lead V1(PtfV1) in the ECG of non–ST-segment elevation acute coronary syndrome (NSTE-ACS) patients during hospitalization and the long-term major adverse cardiovascular events (MACEs) of patients. Methods A total of 595 patients who received coronary angiography and were confirmed as NSTE-ACS in the coronary heart disease database of Department of Cardiology of West China Hospital were continuously included. The PtfV1 and other clinical data at admission and discharge were collected and dynamically observed. The end events of follow-up observation were MACEs. Results Follow-up was performed on 595 patients for 24.71 ± 1.95 months. There were 127 PtfV1(+) and 468 PtfV1(–) at admission, and the incidences of MACEs were 14.2% and 11.1%, respectively (P = 0.731). Compared with patients with persistent PtfV1(–) ECG at admission and discharge, 53 patients with persistent PtfV1(+) ECG at admission and discharge had increased risk for MACEs (HR: 2.221, 95% CI: 1.072–4.601, P = 0.032); 94 patients with new PtfV1(+) ECG at discharge also had significantly increased risk for MACEs (HR: 2.993, 95% CI: 1.660–5.397, P = 0.000). Conclusions NSTE-ACS patients with persistent PtfV1(+) ECG indicators at admission and discharge and new PtfV1(+) at discharge had significantly increased risk of MACEs.

Ischemia and subsequent reperfusion (I/R) damage kidney tubular cells and consequently impair renal function. Rabbit bone marrow mesenchymal stem cells (BM-MSCs) expressing human bone morphogenic protein-7 (hBMP-7) regenerated tubular cells and improved renal function in a kidney I/R model. Rabbits were injected immediately after I/R with one of the following: (i) hBMP-7-transduced BM-MSCs (BM-MSCshBMP-7); (ii) enhanced green fluorescent protein–transduced BM-MSCs (BM-MSCsEGFP); or (iii) PBS. The activity of superoxide dismutase (SOD) was higher, and the amount of malondialdehyde (MDA) was lower in the BM-MSCshBMP-7 group than in the BM-MSCsEGFP group. Both the BM-MSCshBMP-7 group and the BM-MSCsEGFP group had higher SOD activity and lower amounts of MDA than the PBS group. Bcl-2- and Bcl-2-associated X protein levels, and other variables, indicated the regeneration of the kidney in both experimental groups. However, the BM-MSCs hBMP-7 group showed higher activity than the BM-MSCsEGFP group, indicating that the combined strategy of BM-MSC transplantation with hBMP-7 gene therapy could be a useful approach for the treatment of renal IRI.

We investigate the nucleation on heating/loading paths and its effects on the olivine phase transformation and the determinations of nucleation rate in in-situ experiments by the numerical simulation based on the kinetic parameters from low temperature experiments in of Ni2SiO4 olivine phase transformation[1]. Results show that the high temperature experiments, of which samples are first loaded and then heated to the experimental conditions after annealing, are greatly affected by the nucleation during heating. The predicted nucleation rates based on these experiments are obviously overrated. Especially in the case that most of experiments have high target temperatures, the predicted nucleation rates will significantly deviate from their true values, which will have influences on the evaluations of olivine grain size and the rheological structures of subduction zones. Although there are many growth data of Mg2SiO4 olivine and a rough evaluation on the nucleation rate of (Mg0.89Fe0.11)2SiO4 olivine based on the feature of grain impingement, only Ref.[2] showed some nucleation rates of Mg2SiO4 olivine from in-situ high temperature experiments, in which the sample is finally heated to the target experimental condition. The results in present study suggest that the experiments with low target temperature or those reached their experimental condition finally by loading are needed to derive the correct nucleation parameters of mantle olivine.

To examine the biodegradability and bone healing effect of a novel biodegradable coralline hydroxyapatite after implanting into the proximal tibia of rabbit. Seventy New Zealand white rabbits were enrolled, bone defects about 10 × 5 × 3 mm3 of bilateral proximal tibias were prepared by drilling, then coralline hydroxyapatite and iliac crest bone were grafted into bilateral bone defects, respectively. Each time five rabbits were sacrificed at 1, 2, 3, 4, 6, 8, 10, 12, 20, 24, 32, 36, 40, and 60 weeks after surgery. Then a series of examination were carried out, including eye view, roentgenographically, and nondecalcification histological examination. Eye view and roentgenographical examination indicate that all the defects grafted with coralline hydroxyapatite exhibited bone fusion, similar to the iliac crest autograft. The bone density of the graft site decreases with time on the X-ray film. Nondecalcification histological examination results are as followed: In the early time on the sections, the coralline hydroxyapatite looks like interlinked trabecula. Few lymphocytes infiltrate around the trabecula. With time extending, coralline hydroxyapatite looks like thin line or thin circle remnant. The degradation sites are filled with renascence bone. Medulla cavity can be seen in the degradation sites. After grafted in body, coralline hydroxyapatite exhibits little local and general abnormal reaction. It conducts good bone fusion of fracture. Coralline hydroxyapatite can be degraded after grafted into body, which is good for remodeling of bone healing. Hence coralline hydroxyapatite is an ideal bone graft substitute of autograft. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009

The present boundaries between the Philippine Sea (PH) plate and its surrounding plates are determined based on the evolution history of the Philippine Sea and the earthquake distribution around the Philippine Sea. The deformation inside the Philippine Sea plate and along the boundary of PH-Eurasia (EU) plate is studied by comparing the observisional data of geophysics, geology, and GPS with the theoretically calculated results for the Euler parameters of the Philippine Sea plate. The interaction between the Philippine Sea plate and the Eurasian plate is analyzed using the geophysical , geological and GPS data. It is suggested that the interaction is different in different sections of the PH-EU boundary. The PH plate produces strong compression to the Eurasian plate along the Nankai trough. There is no compression along the Ryukyu trench and probably there is an extension caused by the secondary mantle flow. The collision of two plates at the Taiwan area causes strong compression to southeast part of Chinese continent. There is a deformation belt in the Philippine islands between the Philippine Sea plate and the Eurasian plate, which makes interaction between the two plates be weakened and there is no influence on the southern China Sea from the Philippine Sea plate.

We calculated the negative buoyancy of subducting lithospheres based on numerical simulations of the temperature fields by means of 2-D FEM. The values of the negative buoyancy increase with depth in depths of h 740 km. On the other hand, there is a decrease of negative buoyancy in depths of 660 to 740 km, because there is phase transformation from ringwoodite to perovskite, which prevents slab penetrating into the lower mantle. Metastable olivine changes the distribution of negative buoyancy between depths of 400 to 660 km. Especially, it drastically altered the increasing trend of negative buoyancy with depth, leading to a net decrease of negative buoyancy below the 400 km depth. The existence of metastable olivine reduces the increased value of negative buoyancy with depth, which would make the penetration through 660 km discontinuity more difficult. Moreover, it would greatly change the pattern of stress distribution in and around the area of metastable olivine.

Results of numerical simulation show that positive velocity anomalies exist in most parts of subduction zones. These values reach their maxima at approximately 400 and 550 km depths, which are consistent with the wave velocity structures determined by seismic tomography. Though resolution is low, seismic tomography shows the basic features of P-wave velocity variations in subduction zones. Data from regional stations indicate that P-wave velocity anomalies can be positive or negative in the range from -10% to 9%. Low velocity anomalies exist at the depth of about 700 km, and metastable olivine leads to formation of low velocity regions that decline along the dip directions of subduction zones. Low resolution of seismic tomography is an obstacle to show detailed P-wave velocity structure of subduction zones. To investigate fine structures of subduction zones, we should use high-resolution data obtained from regional networks.