Search

Background: Ventricular septal defect (VSD) is one of the most common congenital heart defects. Currently, surgery remains the treatment of choice. However, transcatheter techniques for closing of various types of VSDs have become an alternative. Aims: The objective of our study was to present the outcomes of transcatheter closure of various types of VSD based on a systematic review of recent publications. Methods: A systematic review of studies published in English between January 2014 and March 2020 was performed using the PubMed database (MEDLINE) independently by 2 reviewers. Data on success and complication rates were extracted. Studies including fewer than 5 patients and those with acquired VSD were excluded from the analysis. Results: Finally, 44 studies were included for analysis, with a total number of 4050 patients. The pooled estimate of the overall success rate based on the random effects model was 97.96% (95% CI, 97.37–98.56; Q test P 0.99; I 2 = 0%) for permanent VSD. Conclusions: Transcatheter closure of selected VSDs appears to be an effective and safe method of treatment. Recent studies have shown high rates of successful interventions with a low incidence of complications.

Recently, catalysts with hydrotalcites and hydrotalcite-derived compounds have attracted particular interest due to their specific properties, mostly well-developed texture, high thermal stability, and favorable acid–base properties. In this work, we report the investigation of ammonia synthesis on barium-promoted cobalt catalysts supported on hydrotalcite-derived Mg-Al mixed oxides with different Mg/Al molar ratios. The obtained catalysts were characterized using TGA-MS, nitrogen physisorption, XRPD, TEM, STEM-EDX, H2-TPD, CO2-TPD, and tested in ammonia synthesis (470 °C, 6.3 MPa, H2/N2 = 3). The studies revealed that the prepared Mg-Al mixed oxides are good candidates as support materials for Co-based catalysts. However, interestingly, the support composition does not influence the activity of Ba/Co/Mg-Al catalysts. The change in Mg/Al molar ratio in the range of 2–5 did not significantly change the catalyst properties. All the catalysts are characterized by similar textural, structural, and chemisorption properties. The similar density of basic sites on the surface of the studied catalysts was reflected in their comparable performance in ammonia synthesis.