Myocarditis can be divided into two categories, fulminant myocarditis (FM) and non-fulminant myocarditis (NFM), which is based on the medical history, clinical manifestation, physical examination, examination result, and test result (1). FM is the most serious and special type of myocarditis, which is characterized by its acute and explosive nature (1, 2). FM is a sudden-onset and life-threatening disease and has a high fatality rate. The study indicated that the mortality rate of FM was more than 50%, though FM only occupied approximately 10–38% of all cases of acute myocarditis (2–4).

Fulminant myocarditis can be caused by viruses, bacteria, and non-infectious origins, and the virus is the main etiology (2). Several specific conditions may result in FM, such as lymphocytic myocarditis, giant cell myocarditis, eosinophilic myocarditis, and immune checkpoint inhibitors (ICI)-associated myocarditis (3, 5, 6). Coronavirus has been also reported to be associated with FM. For example, studies showed that OC43 subtype coronavirus and coronavirus disease (COVID-19) are related to FM (7, 8). Besides, studies indicated that the influenza A (HINI) pandemic was related to a high prevalence of FM (9, 10).

Fulminant myocarditis is difficult to diagnose, because the manifestations are often atypical, such as chest pain, arrhythmia, and dyspnea (11). In addition, most patients with FM are often younger and healthier and are easy to be ignored (3). FM can lead to cardiovascular damage and ventricular dysfunction (1, 12), presenting with cardiogenic shock, progressive hemodynamic, and fatal arrhythmia (13, 14). The above manifestations may occur about 2 weeks after virus infection, which may be life-threatening for patients (3, 15). The patients can be rescued if they receive therapy in time. For example, mechanical circulatory support is an effective therapy for FM (2, 16). Early recognition, diagnosis, and treatment are very important, which is the basis of favorable outcomes (17). It is important to note that although the early mortality of FM is high, the long-term prognosis of FM is still controversial. Some studies reported that the long-term prognosis is better than patients with acute myocarditis once patients pass the acute crisis. For example, an 11-year study found that patients with FM had a 93% survival rate if they did not receive heart transplantation, while the survival rate of the patients with acute myocarditis was only 45% (12). But some studies show that the outcome of the FM is worse than the NFM (18). For example, a 7-year study found that patients diagnosed with FM with left ventricular systolic dysfunction have higher rates of cardiac death and heart transplantation when compared with patients with NFM. In the future, the researchers need to carry out more parallel studies to explore the outcome difference between FM and NFM, maybe the subtype of FM.

There were reviews of FM, and they were mainly concentrated on the etiology, diagnosis, therapy, or outcome of FM (19, 20). In addition, they often paid attention to a specific topic of FM and did not present an overall result of FM research for readers. As researchers pay more attention to FM, the number of documents published has been increasing, and the research topics have been enriched. Therefore, to understand the research trend of FM deeply, a comprehensive literature analysis needs to be carried out from a bibliometric perspective. Bibliometric analysis is an effective way to explore and analyze large volumes of scientific data (21), and it has been used in various areas (22–24). In this study, the bibliometric method will be used to gain a better understanding of the research on FM based on the Web of Science (WoS) core collection database, which can provide a reference for researchers in the future.

To analyze and visualize the data collected, Microsoft Excel software, HistCite Pro, GunnMap 2, BibExcel, and the Java program VOSviewer software were used. The workflow of the methodology is shown in Figure 1.

The most prolific countries, journals, institutions, authors, and main research category concerning FM and the influential articles in this area were displayed in this part.

Fulminant myocarditis is a sudden-onset and life-threatening disease (3). Researchers have paid much attention to FM, including the diagnosis (11), therapy (53), and the relationship with other diseases (8). In the past three decades, the number of articles related to FM has been increasing. To better learn the research trends of FM, the bibliometric analysis was carried out, which could contribute to capturing the hot topic and research gap so that the researchers can gain the information quickly.

The first article about FM was published in 1985. Overall, the publications have been with fluctuating growth. In addition, the number of articles has grown rapidly since 2019, which might attribute to the international meeting related to FM held in 2019 (54). In the research about FM, 71 countries have concentrated, and they cooperate. The United States has played an important role in this area, publishing the most articles. In addition, 50% of the productive journals were from the United States. Japan played a second role in the number of articles, followed by China, Germany, and France.

The co-occurrence of keywords was analyzed to understand the research content better. The results indicate that there were four main topics in the area of FM: (I) Concentrate on the application of mechanical circulatory support to patients diagnosed with FM, especially for those with cardiogenic shock (55, 56). In addition, children with FM have been paid much attention to (57, 58). (II) Analyze diagnosis methods of FM, such as the endomyocardial biopsy (59), cardiac magnetic resonance (60), and the clinical manifestations (61). (III) Explore the etiology and pathogenesis of myocarditis, and the virus infection was the most popular mechanism, such as COVID-19 (62), parvovirus b19 (63), and influenza virus (64, 65). (IV) Monitor the ICI-associated with myocarditis (6, 66).

To further understand the topic, the research content of the top three prolific authors, the first three highly cited authors, and the core authors of co-citation network analysis were analyzed.

Klingel K, Ammirati E, Frigerio M, and Izumi T were identified as the top four prolific authors. Klingel K was the most productive author in this area, whose research area could be classified into two categories. On the one hand, the pathogenesis of FM has been paid much attention to since 2001. For example, Klingel K explored the mechanism of the parvovirus B19 (67), human herpesvirus 6 (67), and coxsackievirus B3 (68) causing FM. On the other hand, the therapy of FM has been kept an eye on since 2008, such as the role of Artesunate in the treatment of human herpesvirus 6B myocarditis (69), the protective role of effective chemokine secretion by dendritic cells and expansion of cross-presenting CD4(−)/CD8(+) in the coxsackievirus myocarditis (70), and mechanical circulatory support (71). Ammirati E and Frigerio M were the second productive authors, and their research hotspots were similar. They both paid attention to the prognosis and outcome of FM. For example, they were concerned about the outcomes of patients presenting with life-threatening ventricular arrhythmias (72) and explored the survival difference between FM and NFM (73). In addition, they both paid attention to some special cases, such as the OC43 subtype coronavirus-associated FM (7) and FM masked by acalculous cholecystitis (74). Compared with Ammirati E, Frigerio M also paid attention to mechanical circulatory support (75). Izumi T was the third productive author, who mainly kept an eye on the etiology, therapy, and outcome of FM, such as the mechanism of giant-cells associated myocarditis (76), the therapeutic effect of the cardiopulmonary support system for FM (77), and long-term prognosis of patients diagnosed with FM surviving from cardiopulmonary support (78). In addition, Izumi T also paid attention to the relationship between the influenza pandemic and FM (9). Puzanov I, Moslehi JJ, and Ernstoff MS were the top three highly cited authors. Their research area was extremely similar, and they all paid much attention to ICI-associated with myocarditis (6, 35). In addition, the publishing time of their article ranges from 2016 to 2021, which means that researchers have paid much attention to this area in the recent 5 years. Cooper LT, Mccarthy RE, Maisch B, Chen YS, Acker MA, and Johnson B were identified as the important contributors in this area by co-citation network analysis. Cooper LT mainly concentrated on the diagnosis, therapy, and outcome of giant cell myocarditis (59, 79). Mccarthy RE is concerned about the outcome of FM as compared with NFM (36). Maisch B kept an eye on etiology-directed immune therapies for myocarditis (80). The interest of Chen YS and Acker MA was similar; they both paid attention to the application of mechanical circulatory support in the treatment of FM (44, 81). Johnson B had an interest in the early recognition, clinical manifestations, and interventions of ICI-associated with FM (6, 37).

To a large extent, the research areas of key authors were similar to the results of keyword co-occurrence, the theme of the top 10 cited articles. With the understanding of FM, the research content has gradually been deepened. In addition, the recognition ability has been also improved. For example, the researchers have identified a new etiology of FM in recent years, that is, ICI (53). Although ICI is an important therapy for cancer patients, it can have serious side effects on patients, which can lead to FM (3). From the above analysis, we found that researchers have paid close attention to this area, which may have a significant influence on cancer patients. In addition, researchers have been continuing in exploring the diagnosis, therapy, and outcome of FM. In addition, they have paid attention to etiology-directed management (80). Researchers will have a better understanding of FM with the deepening of research.

This study has managerial implications for academia and researchers, and it has analyzed the research area of FM from the bibliometric perspective, which could help researchers have a holistic understanding of this area under the challenge of more articles being published. The research results help us learn the paper publishing trends, the countries and institutions participating in this area, the main journals, influential authors, the research trends, and hotspots of this area. According to the results, researchers can quickly identify the content they are interested in. For example, it can help authors choose a journal that is suitable for them when submitting their manuscript according to the journal analysis, and they also can find the potential cooperator according to the author’s analysis. In addition, researchers can quickly catch the research hotspots, which can guide their research. In general, this study can provide a reference for researchers to some extent.

This study provides a systematic analysis for us. But, notably, there are some limitations needed to be illustrated. First, the only information source for this study was from the WoS database, and the documents not covered by WoS were not involved. Second, the data were confined to articles published in English only. Finally, there may be a gap between the actual research conditions and the results of bibliometric analysis because of certain time factors. For example, the database updates the study continuously.

Fulminant myocarditis can bring a serious threat to an individual’s life. Researchers are concerned about the disease, whether the etiology or the therapy. In addition, the diagnosis and recognizing ability have been also paid attention to. To have a comprehensive understanding of FM, this study carried out a bibliometric analysis of the study data. The results depicted the contributor authors, the hot topic, the participating countries, etc., which could provide a guideline for researchers. The results will deepen researchers’ understanding and lay the foundation for them to carry out research in the future.

This study showed that the following points should be paid high attention to in the future. First, productive countries should develop more international cooperation. Second, authors should make more contributions to FM in the future, because only 54 of 4,411 authors published 5 more documents. Third, researchers can pay more attention to ICI-associated myocarditis, research progress on etiology, diagnosis, therapy, and outcomes of FM, such as the new virus infection, the mechanical support option, and etiology-directed management.

The original contributions presented in this study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.

WMY, XFH, ZZW, and XYH wrote the main manuscript text. WMY, XYH, LJL, and JC prepared the Figures 1–8. WMY, XYH, and GZ collected, processed, and analyzed the data. All authors reviewed the manuscript.