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As bioprosthetic aortic valve replacement (AVR) extends to younger cohorts, tissue durability is of paramount importance. We report 7-year outcomes from an AVR bioprosthesis utilizing novel tissue. This was an international investigational device exemption trial for novel AVR with annual follow-up and a subset re-consented at 5 years for extended 10-year follow-up. Safety end points and echocardiographic measurements were adjudicated by an independent clinical events committee and by a dedicated core laboratory, respectively. Between January 2013 and March 2016, 689 patients underwent AVR with the study valve. Mean age was 66.9 ± 11.6 years, Society of Thoracic Surgeons risk score was 2.0% ± 1.8%, and 74.3% of patients were New York Heart Association functional class II and III. Five-year follow-up was completed by 512 patients, and 225 re-consented for extended follow-up. Follow-up duration was 5.3 ± 2.2 years (3665.6 patient-years), and 194 and 195 patients completed 6- and 7-year follow-ups, respectively. One-, 5-, and 7-year freedom from all-cause mortality was 97.7%, 89.4%, and 85.4%, respectively. Freedom from structural valve deterioration at 7 years was 99.3%. At 7 years, effective orifice area and mean gradients were 1.82 ± 0.57 cm2 (n = 153), and 9.4 ± 4.5 mm Hg (n = 157), respectively. At 7 years, predominantly none (96.8% [152 out of 157]) or trivial/trace (2.5% [4 out of 157]) paravalvular regurgitation and none (84.7% [133 out of 157]) or trivial/trace (11.5% [18 out of 157]) transvalvular regurgitation were observed. We report the longest surgical AVR follow-up with novel tissue in an investigational device exemption trial utilizing an independent clinical events committee and an echocardiography core laboratory. This tissue demonstrates excellent outcomes through 7 years and is the benchmark for future surgical and transcatheter prostheses. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: High mechanical shear stress (HMSS) generated by blood pumps during mechanical circulatory support induces blood damage (or function alteration) not only of blood cell components but also of plasma proteins. Methods: In the present study, fresh, healthy human blood was used to prime a blood circuit assisted by a CentriMag centrifugal pump at a flow rate of 4.5 L/min under three pump pressure heads (75, 150, and 350 mm Hg) for 4 h. Blood samples were collected for analyses of plasma‐free hemoglobin (PFH), von Willebrand factor (VWF) degradation and platelet glycoprotein (GP) IIb/IIIa receptor shedding. Results: The extent of all investigated aspects of blood damage increased with increasing cross‐pump pressure and duration. Loss of high‐molecular‐weight multimers (HMWM)‐VWF in Loop 2 and Loop 3 significantly increased after 2 h. PFH, loss of HMWM‐VWF, and platelet GPIIb/IIIa receptor shedding showed a good linear correlation with mean shear stress corresponding to the three pump pressure heads. Conclusions: HMSS could damage red blood cells, cause pathological VWF degradation, and induce platelet activation and platelet receptor shedding. Different blood components can be damaged to different degrees by HMSS; VWF and VWF‐enhanced platelet activation may be more susceptible to HMSS. [ABSTRACT FROM AUTHOR]

This study investigated the safety and effectiveness of surgical aortic valve replacement with RESILIA tissue (Edwards Lifesciences) through 5 years in patients with native bicuspid aortic valves. Outcomes were compared with those for patients with tricuspid aortic valves. Of 689 patients from the COMMENCE (ProspeCtive, nOn-randoMized, MulticENter) trial who received the study valve, 645 had documented native valve morphology and core laboratory-evaluable echocardiograms from any postoperative visit, which were used to model hemodynamic outcomes over 5 years. Linear mixed-effects models were used to estimate longitudinal changes in mean gradient and effective orifice area. Patients with native bicuspid aortic valves (n = 214) were more than a decade younger than those with tricuspid aortic valves (n = 458; 59.8 ± 12.4 years vs 70.2 ± 9.5 years; P <.001). The bicuspid aortic valve cohort exhibited no structural valve deterioration over 5 years, and rates of paravalvular leak and transvalvular regurgitation were low (0.7% and 2.9%, respectively [all mild] at 5 years). These outcomes mirrored those in patients with native tricuspid aortic valves. The model-estimated postoperative mean gradient and effective orifice area, as well as the rate of change of these outcomes, adjusted for age, body surface area, and bioprosthesis size, did not differ between the 2 cohorts. Among patients with bicuspid aortic valves, RESILIA tissue valves demonstrated excellent outcomes to 5 years, including no structural valve deterioration and very low rates of paravalvular and transvalvular regurgitation. These results are encouraging for RESILIA tissue durability in young patients. [ABSTRACT FROM AUTHOR]

The collective efforts of scientists over multiple decades have led to advancements in molecular and cellular biology-based technologies including genetic engineering and animal cloning that are now being harnessed to enhance the suitability of pig organs for xenotransplantation into humans. Using organs sourced from pigs with multiple gene deletions and human transgene insertions, investigators have overcome formidable immunological and physiological barriers in pig-to-nonhuman primate (NHP) xenotransplantation and achieved prolonged pig xenograft survival. These studies informed the design of Revivicor's (Revivicor Inc, Blacksburg, VA) genetically engineered pigs with 10 genetic modifications (10 GE) (including the inactivation of 4 endogenous porcine genes and insertion of 6 human transgenes), whose hearts and kidneys have now been studied in preclinical human xenotransplantation models with brain-dead recipients. Additionally, the first two clinical cases of pig-to-human heart xenotransplantation were recently performed with hearts from this 10 GE pig at the University of Maryland. Although this review focuses on xenotransplantation of hearts and kidneys, multiple organs, tissues, and cell types from genetically engineered pigs will provide much-needed therapeutic interventions in the future. [ABSTRACT FROM AUTHOR]

Background: Neutrophils take part in the innate immune response, phagocytosis, and pro‐inflammatory cytokine release. The phagocytic capacity of circulating neutrophils in patients on continuous flow (CF) ventricular assist device (VAD) has not been well studied. Methods: Blood samples from 14 patients undergoing CF‐VAD implantation were collected and analyzed preoperatively (at baseline) and on postoperative days (POD) 3, 7, 14, and 28. Flow cytometry was used to assess the surface expression levels of CD62L, CD162, and macrophage antigen‐1 (MAC‐1) and neutrophil phagocytic capacity. Interleukin 1 (IL1), IL6, IL8, TNF‐α, neutrophil elastase, and myeloperoxidase in plasma were measured using enzyme‐linked immunosorbent assays. Results: Among the 14 patients, seven patients had preoperative bridge device support. Relative to baseline, patients with no bridge device had elevated leukocyte count and neutrophil elastase by POD3 which normalized by POD7. Neutrophil activation level, IL6, IL8, and TNF‐α increased by POD3 and sustained elevated levels for 7–14 days postoperatively. Elevated neutrophil phagocytic capacity persisted even until POD28. Similar patterns were observed in patients on a preoperative bridge device. Conclusions: Neutrophil activation and phagocytic capacity increased in response to VAD support, while inflammatory cytokines remain elevated for up to 2 weeks postoperatively. These findings may indicate that VAD implantation elicits circulating neutrophils to an abnormal preemptive phagocytotic phenotype. [ABSTRACT FROM AUTHOR]