Aim To evaluate the theme trends and knowledge structure of multifetal pregnancy reduction (MPR)‐related literature by using bibliometric analysis. Methods Published scientific papers regarding MPR were retrieved from the PubMed database. Data extraction and statistics were conducted using Bibliographic Item Co‐Occurrence Matrix Builder (BICOMB). Furthermore, gCLUTO software was used in the study for bi‐clustering analysis and strategic diagram analysis. Results According to the search strategy, 906 total papers were included. Among all the extracted MeSH terms, 41 high frequency ones were identified and hotspots were clustered into four categories. In the strategic diagram, research on intrauterine treatment of MPR was most well developed. In contrast, statistical data on the sequelae of fetal reduction surgery and applications of MPR in assisted reproductive technologies were relatively immature. Conclusion The analysis of common terms among the high‐frequency network terms in multiparous pregnancy reduction can help researchers and clinicians understand the hotspots, key topics, and issues to be discovered on MPR. Research on intrauterine treatment of MPR was most well developed.

Background: Primary percutaneous coronary intervention is the treatment of choice in ST-segment elevation myocardial infarction and no-reflow phenomenon is still an unsolved problem.Methods: We searched PubMed, EmBase, and Cochrane Central Register of Controlled Trials for relevant randomized controlled trials. The primary endpoint was the incidence of major adverse cardiac events and the secondary endpoint was the incidences of no-reflow phenomenon and complete resolution of ST-segment elevation. Results: Eighteen randomized controlled trials were enrolled. Nicorandil significantly reduced the incidence of no-reflow phenomenon (OR, 0.46; 95% CI, 0.36 to 0.59; P＜0.001; I2=0%) and major adverse cardiac events (OR, 0.42; 95% CI, 0.27 to 0.64; P＜0.001; I2=52%). For every single outcome of major adverse cardiac events, only heart failure and ventricular arrhythmia were significantly improved with no heterogeneity (OR, 0.36; 95% CI, 0.23 to 0.57, P＜0.001; OR, 0.43; 95% CI, 0.31 to 0.60, P＜0.001 respectively). A combination of intracoronary and intravenous nicorandil administration significantly reduced the incidence of major adverse cardiac events with no heterogeneity (OR, 0.24; 95% CI, 0.13 to 0.43, p＜0.001), while a single intravenous administration could not (OR, 0.66; 95% CI, 0.40 to 1.06, p=0.09; I2=52%). Conclusions: Nicorandil can significantly improve no-reflow phenomenon and major adverse cardiac events in patients undergoing primary percutaneous coronary intervention. The beneficial effects on major adverse cardiac events might be driven by the improvements of heart failure and ventricular arrhythmia. A combination of intracoronary and intravenous administration might be an optimal usage of nicorandil.