Objective: Biological valves exhibit characteristic curves (CC) regarding transvalvular gradient, resistance, and effective orifice area when correlated with a physiological cardiac output range (CO). The slope of the curve of transvalvular resistance over atypical CO range characterizes the clinical performance of the valve. These information may support an individualized decision towards the most adequate valvetype. Methods: In an extracorporeal mock circuit two types of stented biological aortic valves (constructed pericardial valves, Edwards Perimount: EP;porcine cusp valves, Medtronic Mosaic: MM) of 21, 23, and 25 mm were investigated. Mean transvalvular gradient was measured over a range of 1.9 to 7.2l/min CO at asimulated heart rate of 70 beats/min. Transvalvular resistance was calculated and presented as characteristic curves in a log–log-plot against cardiac output.Results: EP valves of all sizes demonstrated low slopes (resistance range; slope: 21mm: 53–79 dynesscm^-5; 0.29; 23mm:44–56dynesscm^-5; 0.12; 25 mm: 38–45 dynesscm^-5; 0.12) while MM valves exhibited steep slopes (resistance range; slope:21mm: 46–169dynesscm^-5; 0.97; 23mm: 36– -146 dynesscm^-5; 0.95; 25mm: 27–64dynesscm^-5;0.68) Conclusions: While constructed pericardial valves demonstrate sufficient hemodynamic performance especially in the higher CO range porcine cusp valves exhibited minor resistance in the lower CO range. Patients who exercise regularly may therefore profit from a pericardial valve while patients with a small body surface area and little exercise who therefore remain in the lower CO range may be adequately treated with a porcine cusp valve.

Background and Objectives: Developing a prosthetic heart valve that combines the advantageous hemodynamic properties of its biological counterpart with the longevity of mechanical prostheses has been a major challenge for heart valve development. Anatomically inspired artificial polymeric heart valves have the potential to combine these beneficial properties, and innovations in 3D printing have given us the opportunity to rapidly test silicone prototypes of new designs to further the understanding of biophysical properties of artificial heart valves. TRISKELION is a promising prototype that we have developed, tested, and further improved in our institution. Materials and Methods: STL files of our prototypes were designed with FreeCad 0.19.2 and 3D printed with an Agilista 3200W (Keyence, Osaka, Japan) using silicones of Shore hardness 35 or 65. Depending on the valve type, the support structures were printed in AR-M2 plastics. The prototypes were then tested using a hemodynamic pulse duplicator (HKP 2.0) simulating an aortic valve cycle at 70 bpm with 70 mL stroke volume (cardiac output 4.9 L/min). Valve opening cycles were visualized with a high-speed camera (Phantom Miro C320). The resulting values led to further improvements of the prototype (TRISKELION) and were compared to a standard bioprosthesis (Edwards Perimount 23 mm) and a mechanical valve (Bileaflet valve, St. Jude Medical). Results: We improved the silicone prototype with currently used biological and mechanical valves measured in our setup as benchmarks. The regurgitation fractions were 22.26% ± 4.34% (TRISKELION) compared to 8.55% ± 0.22% (biological) and 13.23% ± 0.79% (mechanical). The mean systolic pressure gradient was 9.93 ± 3.22 mmHg (TRISKELION), 8.18 ± 0.65 mmHg (biological), and 10.15 ± 0.16 mmHg (mechanical). The cardiac output per minute was at 3.80 ± 0.21 L/min (TRISKELION), 4.46 ± 0.01 L/min (biological), and 4.21 ± 0.05 L/min (mechanical). Conclusions: The development of a heart valve with a central structure proves to be a promising concept. It offers another principle to address the problem of longevity in currently used heart valves. Using 3D printing to develop new prototypes provides a fast, effective, and accurate way to deepen understanding of its physical properties and requirements. This opens the door for translating and combining results into modern prototypes using highly biocompatible polymers, internal structures, and advanced valve layouts.

Background Endocarditis is continuously increasing. Evidence exist that the prognosis is adversely affected by the extent of the disease. We looked at risk factors influencing in-hospital mortality (HM). Patients and Methods Between 2010 and 2019, 484 patients, 338 males (69.8%) with mean age of 66.1 years were operated on because of proven endocarditis. In a retrospective study, a risk factor analysis was performed. Results Overall HM was 30.17%. Significant influencing factors (odds ratios [ORs] or p-value) for HM were: age (p = 0.004), logistic EuroSCORE (p< 0.001), gender (OR = 1.64), dialysis (OR = 2.64), hepatic insufficiency (OR = 2.17), reoperation (OR = 1.77), previously implanted valve (OR = 1.97), periannular abscess (OR = 9.26), sepsis on admission (OR = 12.88), and number of involved valves (OR = 1.96). Development of a sepsis and HM was significantly lower if Streptococcus mitis was the main pathogen in contrast to other bacteria (p< 0.001). Staphylococcus aureus was significantly more often found in patients with a previously implanted prosthesis (p = 0.03) and in recurrent endocarditis (p = 0.02), while it significantly more often showed peripheral septic emboli than the other pathogens (p< 0.001). Conclusion Endocarditis remains life-threatening. Severe comorbidities adversely affected early outcome, particularly, in presence of periannular abscesses. Patients with suspected endocarditis should be admitted to a specialized heart center as early as possible. Streptococcus mitis appears to be less virulent than S. aureus. Further studies are required to verify these findings.

Background Endocarditis remains one of the most threatening diagnoses in cardiac surgery and is still increasing. Particularly, device-related as well as prosthetic endocarditis appears to be on the rise. Early mortality and periprocedural complications are high jeopardizing the success of surgical efforts. We looked at the development of the numbers and the distribution of endocarditis in an all-comer analysis. Methods From 2003 to 2017, 752 patients with endocarditis were transferred to our cardiosurgical institution (mean age 65 ± 13 years; mean logistic EuroSCORE 28.01%; males 74.33%). A total of 89.49% of them were surgically treated; 30.01% redo cases thereof; and 9.17% had been operated previously for acute endocarditis. Results While the total number of cardiosurgical procedures remained relatively stable throughout the years, 20 patients were admitted in 2003 and 79 in 2017 yielding more than fourfold increase (p < 0.001). Early mortality of all patients was 25.1%. Septic emboli occurred in 23.7% and 43.8% cerebral emboli thereof. A significant increase of aortic, mitral, and tricuspid valves involvement was observed (p < 0.001). An increase of device-related endocarditis was also noted (p < 0.001). Conclusion Endocarditis remains a serious problem with high early mortality and morbidity. The vast increase of electrophysiological device implantations has resulted in an increase of tricuspid valve involvement. Liberalization of endocarditis prophylaxis, that is, more restrictive use of antibiotics in 2007 may have at least partially contributed to an increase of the individual risk to suffer from acute endocarditis. A renaissance of a stricter endocarditis–prophylaxis may thus be considered.