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Background: Porous polyethylene (PPE) implants are used for the reconstruction of tissue defects but have a risk of rejection in case of insufficient ingrowth into the host tissue. Various growth factors can promote implant ingrowth, yet a long-term gradient is a prerequisite for the mediation of these effects. As modification of the implant surface with nanocarriers may facilitate a long-term gradient by sustained factor release, implants modified with crosslinked albumin nanocarriers were evaluated in vivo., Methods: Nanocarriers from murine serum albumin (MSA) were prepared by an inverse miniemulsion technique encapsulating either a low- or high-molar mass fluorescent cargo. PPE implants were subsequently coated with these nanocarriers. In control cohorts, the implant was coated with the homologue non-encapsulated cargo substance by dip coating. Implants were consequently analyzed in vivo using repetitive fluorescence microscopy utilizing the dorsal skinfold chamber in mice for ten days post implantation., Results: Implant-modification with MSA nanocarriers significantly prolonged the presence of the encapsulated small molecules while macromolecules were detectable during the investigated timeframe regardless of the form of application., Conclusions: Surface modification of PPE implants with MSA nanocarriers results in the alternation of release kinetics especially when small molecular substances are used and therefore allows a prolonged factor release for the promotion of implant integration.

Objectives: Transcatheter aortic valve implantation (TAVI) in patients with low coronary heights is generally denied but is not impossible. Information about these high-risk procedures is sparse., Methods: Since May 2008, data of more than 3000 patients who had TAVI were prospectively collected in the institutional TAVI Karlsruhe registry. Characteristics, peri- and postoperative outcome of patients with low coronary heights of ≤7 mm were analysed according to the Valve Academic Research Consortium-2., Results: Eighty-six patients with an average coronary height of 6.4 ± 1.1 mm (mean age 81.0 ± 5.3 years, logistic EuroSCORE I 19.6 ± 13.3%) were treated. TAVI was performed in 72 transfemoral (83.7%) and 14 transapical (16.3%) cases using 44 CoreValve/Evolut R (51.2%), 21 Sapien XT/S3 (24.4%), 14 ACURATE (16.3%), 5 Lotus (5.8%) and 2 Portico (2.3%) prostheses. Ten procedures were valve-in-valve (VinV) TAVI (VinV, 11.6%). The 72-h, 30-day, 1-year and follow-up (3.0 ± 1.6 years) mortality rates were 2.3%, 8.0%, 10.5% and 26.7%, respectively. Within 30 days, 4 cardiac deaths and 3 non-cardiac deaths occurred (4.7% and 3.5%). Three coronary obstructions (3.5%) occurred-2 during VinV TAVI. One patient was connected to extracorporeal circulation that could not be weaned later due to an unsuccessful percutaneous coronary intervention. Another patient, the only conversion (1.2%), required delayed surgical valve replacement. The third patient died of right heart failure after aortic dissection. The procedural success rate was 95.3%. VinV procedures were associated with increased follow-up deaths (P < 0.001; hazard ratio 7.96)., Conclusions: Coronary-related complications in TAVI procedures in patients with coronary heights ≤7 mm occurred less frequently, but once they occurred, they were serious. These TAVI procedures are feasible, with a high procedural success rate, but meticulous preoperative planning should be mandatory. In VinV procedures, the follow-up mortality rate is increased; therefore, we do not recommend these procedures.