Ventricular septal defect is the most common congenital heart disease in children. Transcathe-ter closure is now becoming an alternative treatment to surgical repair for perimembranous ventricular septal de-fect. As more and more patients are treated with interventional therapy,the immediate and long-term complica-tions are increasingly the cause of concern. This review summarizes the occurrence of complications after tran-scatheter closure of ventricular septal defect,mechanism and treatment of the complications,highlighting the oc-currence of cardiac block as a key point.

Objective To analyze the hot research spots of MOOC research of higher medical edu-cation in China. Methods We searched the database of China National Knowledge Infrastrucure (CNKI), VIP database of Chinese journal (VIP), Wanfang Database for published studies on MOOC research of higher medical education from 2005 to April 2015. The high frequency words were counted by an analysis program-Bibliographic Item Co-occurrence Matrix Builder (BICOMB). According to the ranking word frequency threshold formula by Donohue, we collected the high-frequency keywords. The corresponding co-word ma-trixes were constructed by Bibexcel, then the data was input into SPSS 19.0 software for hierarchical clus-tering analysis. Results Finally 2 459 articles were included. 11 177 keywords and 13 high frequency words (the number of the real selected was 24) were taken into account. The keywords “stanford” clus-tered with “education module”, “online education”, “online courses”, “distance education”, “learning pro-cess”, “self-regulated learning”, “information technology”, “classroom teaching”. The keywords “network course” clustered with “teaching design”. The keywords “online learning” clustered with itself. The key-words “challenge” clustered with “colleges and universities”. The keywords “flipped classroom” clustered with“micro-lecture”,“MOOC”,“higher education”, “library”, “teaching module”, “teaching reform”, “big data”,“open education”. The keywords“SPOC”clustered with itself. Conclusion The research of MOOC research of higher medical education in our country has formed the basic characteristics with six hot spots involving teaching design, the model of online learning, dispassion thinking, teaching reform, and develop-ment. And there are many potential areas.

Objective To explore the impact of temperature and environmental factors on the risk of deaths from cardiovascular and cerebrovascular diseases (CVD) in Wuhan during the course of high temperature. Methods The daily CVD death data and meteorological and atmospheric pollutant concentration data during the high temperature process in Wuhan from 2014 to 2019 were collected. The generalized additive models (GAM) were used to obtain the characteristics of meteorological factors, atmospheric pollutant concentrations, high impact factors and thresholds affecting the relative risk of CVD death. Results The analysis results showed that: (1) When the maximum temperature reached 36.7°C and the lowest temperature reached 25.3°C, the relative risk of CVD death increased significantly; (2) The risk of CVD death during the first high temperature process was the largest, and the average CVD excess mortality rate during the first high temperature process from 2014 to 2019 reached 21.7%; and (3) The average temperature, maximum temperature and PM₁₀ during the course of high temperature were important environmental factors that increased the risk of CVD deaths, and the relative risks were 1.14 (95% confidence interval (95% CI): 1.11-1.17), 1.11 (95% confidence interval (95% CI): 1.08-1.15, and 1.06 (95% confidence interval (95% CI): 1.02-1.09), respectively. Conclusion Temperature and PM₁₀ are important environmental factors that increase the risk of death from CVD during the high temperature process in Wuhan from 2014 to 2019, with the first annual high temperature process having the greatest impact on the risk of CVD death.