BACKGROUND: Postoperative pericardial adhesions have been associated with increased morbidity, mortality, and surgical difficulty. Barriers exist to limit adhesion formation, yet little is known about their use in cardiac surgery. The study presented here provides the first major systematic review of adhesion barriers in cardiac surgery. METHODS: Scopus and PubMed were assessed on November 20, 2020. Inclusion criteria were clinical studies on human subjects, and exclusion criteria were studies not published in English and case reports. Risk of bias was evaluated with the Cochrane Risk of Bias Tool. Barrier safety and efficacy data were assessed with Excel and GraphPad Prism 5. RESULTS: 25 studies were identified with a total of 13 barriers and 2,928 patients. Polytetrafluoroethylene (PTFE) was the most frequently evaluated barrier (13 studies, 67% of patients) with an infection rate of 1.14%, bleeding event rate of 0.75%, mortality rate of 1.22%, adhesion formation rate of 37.31%, and standardized tenacity score of 26.50. Several barriers had improved safety and efficacy. In particular, Cova CARD had an infection rate of 0.00%, a bleeding event rate of 0.00%, and a tenacity score of 15.00. CONCLUSIONS: Overall, the data varied considerably in terms of study design and reporting bias. The amount of data was also limited for the non-PTFE studies. PTFE has historically been effective in preventing adhesions. More recent barriers may be superior, yet the current data is non-confirmatory. No ideal adhesion barrier currently exists, and future barriers must focus on the requirements unique to operating in and around the heart.