Table 2.
Characteristics of the Included Studies.
| First Author/Year/Ref | Type of Study | Cohort | Aims | Finding |
|---|---|---|---|---|
| Schwartz et al. (2021) APMIS [88] |
In vitro patch enriched with platelet and Leucocyte-rich fibrin Multicenter (Danemark) |
IE organoid-like model by colonization with IE-associated bacterial isolates S. aureus, S. mitis and Enterococcus faecalis (IE vegetation (IEV) | To establish an in vitro vegetation simulation IE model for fast screening of novel treatment strategies | The surface-associated bacteria displayed increased tolerance to antibiotics compared to planktonic bacteria. IE simulation model with the relevant pathogens S. aureus, S. mitis group, and E. faecalis was established and IE model mirrors the natural IE process |
| Di Domenico et al. (2019) BMC Microbiol. [89] |
Human Multicenter (IT) |
Samples of infected heart tissue. S. aureus 50%, Enterococcus faecalis 25% and Streptococcus gallolyticus 25% | To assess a rapid biofilm identification assay and a targeted antimicrobial susceptibility profile of biofilm-growing bacteria in patients with IE, which were unresponsive to antibiotic therapy | Biofilm-producing bacteria, from surgically treated IE, display a high tolerance to antibiotics, which is undetected by conventional antibiograms |
| Schwartz et al. (2012) APMIS [90] |
Animal model Multicenter (Danemark) |
IE organoid-like model by colonization with IE-associated bacterial isolates S. aureus, S. mitis and Enterococcus faecalis (IEV) | To evaluate the time course of biofilm formation and the impact on antibiotic tolerance development | The antibiotic effect was significantly higher than when treatment was started after the biofilm was allowed to mature |
| Kim et al. (2016) JTCVS [95] |
Human Single Center (USA) |
86 pts Homografts vs. 139 pts Xenograft prostheses vs. 79 pts Mechanical prostheses |
To evaluate resistance to infection | Homografts were more used in PVE (p = 0.002) and methicillin-resistant Staphylococcus (p = 0.002), compared with conventional prostheses. No significant benefit to the use of homografts was demonstrable with regard to resistance to reinfection in the setting of IE |
| Nappi et al. (2018) JTCVS [102] |
Human Single center (France) |
210 pts | To evaluate long-term results of aortic allografts and to identify factors influencing long-term durability | The use of allograft is a valid option in complex infective endocarditis and in women of childbearing age |
| Steffen et al. (2016) JTCVS [113] |
In vitro Single center (Germany) |
10 cryopreserved human allografts | To evaluate the in vitro antimicrobial activity of 3 antibiotic regimens | Allograft antibacterial activity despite long-term storage over 5 years. Antibiotic combinations applied during CHA processing have a significant influence on their infection resistance. Ascending aortic tissue shows a significantly enhanced bacterial resistance against staphylococcal bacteria compared with aortic valves |
Abbreviations: IEV, infective endocarditis vegetation; pts, patients; PVE, prosthetic valve endocarditis; S. aureus, Staphylococcus aureus; S. mitis, Streptococcus mitis.