Trends and Outcomes of Cardiac Transplantation in the Lowest Urgency Candidates

Background Because of discrepancies between donor supply and recipient demand, the cardiac transplantation process aims to prioritize the most medically urgent patients. It remains unknown how recipients with the lowest medical urgency compare to others in the allocation process. We aimed to examine differences in clinical characteristics, organ allocation patterns, and outcomes between cardiac transplantation candidates with the lowest and highest medical urgency. Methods and Results We performed a retrospective analysis of the United Network for Organ Sharing database. Patients listed for cardiac transplantation between January 2011 and May 2020 were stratified according to status at time of transplantation. Baseline recipient and donor characteristics, waitlist survival, and posttransplantation outcomes were compared in the years before and after the 2018 allocation system change. Lower urgency patients in the old system were older (58.5 versus 56 years) and more likely female (54.4% versus 23.8%) compared with the highest urgency patients, and these trends persisted in the new system (P<0.001, all). Donors for the lowest urgency patients were more likely older, female, or have a history of cytomegalovirus, hepatitis C, or diabetes (P<0.01, all). The lowest urgency patients had longer waitlist times and under the new allocation system received organs from shorter distances with decreased ischemic times (178 miles versus 269 miles, 3.1 versus 3.5 hours; P<0.001, all). There was no difference in posttransplantation survival (P<0.01, all). Conclusions Patients transplanted as lower urgency receive hearts from donors with additional comorbidities compared with higher urgency patients, but outcomes are similar at 1 year

Intrinsic metabolic depression in cells isolated from the hepatopancreas of estivating snails

Many animals across the phylogenetic scale are routinely capable of depressing their metabolic rate to 5–15% of that at rest, remaining in this state sometimes for years. However, despite its widespread occurrence, the biochemical processes associated with metabolic depression remain obscure. We demonstrate here the development of an isolated cell model for the study of metabolic depression. The isolated cells from the hepatopancreas (digestive gland) of the land snail (Helix aspersa) are oxygen conformers; i.e., their rate of respiration depends on pO2. Cells isolated from estivating snails show a stable metabolic depression to 30% of control (despite the long and invasive process of cell isolation) when metabolic rate at the physiological pH and pO2 of the hemolymph of estivating snails is compared with metabolic rate at the physiological pH and pO2 of the hemolymph of control snails. When the extrinsic effects of pH and pO2 are excluded, the intrinsic metabolic depression of the cells from estivating snails is still to below 50% of control snails. The in vitro effect of pO2 on metabolic rate is independent of pH and state (awake or estivating), but the effects of pH and state significantly interact. This suggests that pH and state change affect metabolic depression by similar mechanisms but that the metabolic depression by hypoxia involves a separate mechanism.</p

Impact of the new heart allocation policy on patients with restrictive, hypertrophic, or congenital cardiomyopathies.

BackgroundPatients with restrictive or hypertrophic cardiomyopathy (RCM/HCM) and congenital heart disease (CHD) do not derive clinical benefit from inotropes and mechanical circulatory support. Concerns were expressed that the new heart allocation system implemented in October 2018 would disadvantage these patients. This paper aimed to examine the impact of the new adult heart allocation system on transplantation and outcomes among patients with RCM/HCM/CHD.MethodsWe identified adult patients with RCM/HCM/CHD in the United Network for Organ Sharing (UNOS) database who were listed for or received a cardiac transplant from April 2017-June 2020. The cohort was separated into those listed before and after allocation system changes. Demographics and recipient characteristics, donor characteristics, waitlist survival, and post-transplantation outcomes were analyzed.ResultsThe number of patients listed for RCM/HCM/CHD increased after the allocation system change from 429 to 517. Prior to the change, the majority RCM/HCM/CHD patients were Status 1A at time of transplantation; afterwards, most were Status 2. Wait times decreased significantly for all: RCM (41 days vs 27 days; PConclusionsThe new allocation system has had a positive impact on time to transplantation of patients with RCM, HCM, and CHD without negatively influencing survival

Pneumococcal responses are similar in Papua New Guinean children aged 3-5 years vaccinated in infancy with pneumococcal polysaccharide vaccine with or without prior pneumococcal conjugate vaccine, or without pneumococcal vaccination

Trial design: In an earlier trial, Papua New Guinean (PNG) children at high risk of pneumococcal disease were randomized to receive 0 or 3 doses of 7-valent pneumococcal conjugate vaccine (PCV7), followed by a single dose of 23-valent pneumococcal polysaccharide vaccine (PPV23) at 9 months of age. We here studied in a non-randomized follow-up trial the persistence of pneumococcal immunity in these children at 3–5 years of age (n = 132), and in 121 community controls of a similar age with no prior pneumococcal vaccination. Methods: Circulating IgG antibody titers to all PCV7 and PPV23-only serotypes 2, 5 and 7F were measured before and after challenge with 1/5 th of a normal PPV23 dose. Serotype-specific memory B-cells were enumerated at 10 months and 3–5 years of age for a subgroup of study children. Results: Serotype-specific IgG antibody titers before and after challenge were similar for children who received PCV7/PPV23, PPV23 only, or no pneumococcal vaccines. Before challenge, at least 89% and 59% of children in all groups had serotype-specific titers 0.35µg/ml and 1.0 µg/ml, respectively. Post-challenge antibody titers were higher or similar to pre-challenge titers for most children independent of pneumococcal vaccination history. The rise in antibody titers was significantly lower when pre-challenge titers were higher. Overall the relative number of serotype-specific memory B-cells remained the same or increased between 10 months and 3–5 years of age, and there were no differences in serotype-specific memory B-cell numbers at 3–5 years of age between the three groups. Conclusions: Immunity induced by PCV7 and/or PPV23 immunization in infancy does not exceed that of naturally acquired immunity in 3-5-year-old children living in a highly endemic area. Also, there was no evidence that PPV23 immunization in the first year of life following PCV7 priming induces longer-term hypo-responsiveness. © 2017 van den Biggelaar et al