Background Catheter ablation (CA) is an effective treatment for patients with atrial fibrillation (AF). The potential of CA to benefit AF patients with heart failure and preserved ejection fraction (HFpEF) is uncertain. Hypothesis CA may be safe and effective for patients with HFpEF. Methods The Medline, PubMed, Embase, and Cochrane Library databases were searched for studies evaluating CA for AF patients with HFpEF. Results A total of seven trials with 1696 patients were included. Pooled analyses demonstrated similar procedure and fluoroscopy time regarding the use of CA for patients with HFpEF and without HF (weighted mean difference [WMD]: 0.40; 95% confidence interval (CI): −0.01–0.81, p = .05 and [WMD: 0.05; 95% CI: −0.18–0.28, p = .68]). Moreover, CA was effective in maintaining sinus rhythm (SR) in patients with HFpEF and noninferior for patients without HF [risk ratio (RR): 0.92; 95% CI: 0.76–1.10, p = .34). Additionally, CA tended to significantly maintain SR (RR: 4.73; 95% CI: 1.86–12.03, p = .001) and reduce rehospitalization for HF compared with medical therapy (RR: 0.36; 95% CI: 0.19–0.71, p = .003). However, no significant differences were found between two groups regarding the mortality rate ( p = .59). Conclusion CA is a potential treatment strategy for patients with HFpEF and demonstrates equivalent efficacy to that of patients without HF. Moreover, the benefits of CA in maintaining SR and reducing rehospitalization of HF patients were significantly better than those of medical therapy. Additional randomized controlled trials are warranted to confirm our results.

Plasma electrolytic oxidation treatment of 6061 aluminum alloy in a sodium silicate and sodium hydroxide alkaline electrolyte containing different concentrations of cerium nitrate by constant current method. In order to further improve the microstructure compactness and corrosion resistance of the plasma electrolytic oxidation layer on the surface of 6061 aluminum alloy. The effects of Ce (NO3)3 concentration on the roughness, cross section and surface morphology, composition and phase composition, adhesion force and corrosion resistance of ceramic layer were studied by means of true color microscope, scanning electron microscope, X-ray energy spectrometer, X-ray diffractometer, micrometer scratcher and electrochemical workstation. The results show that with the increase of Ce(NO3)3 concentration in the electrolyte, the thickness of the plasma electrolytic oxidation layer increases gradually, and the micropores and cracks increase, and the roughness increases first and then decreases. The plasma electrolytic oxidation layers under different concentrations of Ce (NO3)3 are mainly composed of α-Al2O3, γ-Al2O3 and a small amount of Al2SiO5, The Ce element in the ceramic layer is mainly present in the form of a mixture of Ce(OH)4, CeO2 and Ce2O3.The increase of Ce (NO3)3 concentration reduces the binding force between the plasma electrolytic oxidation layer and the matrix, increases the self-corrosion potential, decreases the self-corrosion current, and weakens the corrosion resistance. The Ce (NO3)3 ceramic layer with a concentration of 0.25 g/L has less micropores and cracks, and has the best compactness. The ceramic layer and the matrix have better bonding strength and exhibit better corrosion resistance.

Microarc oxidation (MAO) layers were prepared using 8g/L Na2SiO3 + 6g/L (NaPO3)6 + 4g/L Na2WO4 electrolyte with the addition of 2g/L Ti3SiC2/Ti3AlC2 particles under constant-current mode. The roughness, porosity, composition, surface/cross-sectional morphology, and frictional behavior of the prepared MAO layers were characterized by 3D real-color electron microscopy, scanning electron microscopy, X-ray energy spectrometry, X-ray diffractometry, and with a tribo-tester. The results showed that the addition of Ti3SiC2 and Ti3AlC2 to the electrolyte reduced the porosity of the prepared layers by 9% compared with that of the MAO layer without added particles. The addition of Ti3SiC2/Ti3AlC2 also reduced the friction coefficient and wear rate of the prepared layers by 35% compared with that of the MAO layer without added particles. It was found that the addition of Ti3AlC2 particles to the electrolyte resulted in the lowest porosity and the lowest wear volume.

WS2/TiO2 composite layer was successfully in situ prepared by plasma electrolytic oxidation method adding Na2S and Na2WO4 into electrolyte. The structure, morphology and frictional properties of the composite layer were investigated by X-ray diffraction, scanning electron microscopy, and 3D confocal microscopy. It was found that the WS2/TiO2 composite layer is denser and has a lower friction coefficient when the adding concentration is 10–20 g/L. The WS2/TiO2 composite layer in situ prepared by plasma electrolytic oxidation is a new method to improve the trilogical hehavior of TC4 alloy.