Accuracy of risk models used for public reporting of heart transplant center performance.

BACKGROUND: Heart transplant programs and regulatory entities require highly accurate performance metrics to support internal quality improvement activities and national oversight of transplant programs, respectively. We assessed the accuracy of publicly reported performance measures. METHODS: We used the United Network for Organ Sharing registry to study patients who underwent heart transplantation between January 1, 2016 and June 30, 2018. We used tests of calibration to compare the observed rate of 1-year graft failure to the expected risk of 1-year graft failure, which was calculated for each recipient using the July 2019 method published by the Scientific Registry of Transplant Recipients (SRTR). The primary study outcome was the joint test of calibration, which accounts for both the total number of events predicted (calibration-in-the-large) and dispersion of risk predictions (calibration slope). RESULTS: 6,528 heart transplants were analyzed. The primary test of calibration failed (p CONCLUSIONS: Risk models employed for publicly-reported graft survival at U.S. heart transplant centers lack accuracy in general and in all subgroups tested. The use of disease-specific models may improve the accuracy of program performance metrics

Changes of land use on peatlands in Poznań region

Celem badań było ustalenie zmian w sposobie użytkowania torfowisk Wielkopolski. Badania, wykonane w 2002 r., prowadzono na 124 torfowiskach o łącznej powierzchni ok. 4000 ha. Prace realizowano za pomocą badań terenowych oraz interpretacji zdjęć lotniczych i satelitarnych, stosując programy komputerowe do prac graficznych w celu określenia obszaru zajmowanego przez poszczególne użytki. Wydzielano łąki jedno- i dwukośne, łąki niekoszone, łąki zakrzewione, ekstensywne pastwiska, szuwary trzcinowe, wody stojące, grunty orne oraz lasy i zadrzewienia. Potwierdzono znaczne zmiany w sposobie użytkowania obiektów w stosunku do stanu z lat: 1957-1969, określonego na podstawie dokumentacji geologicznej torfowisk, 1993-1998 na podstawie zdjęć lotniczych oraz 1989-1991 na podstawie zdjęć satelitarnych. Przy opracowaniu wniosków, obok omawianych badań, wykorzystano wcześniej publikowane wyniki badań własnych [Restoration ..., 2002]. Ustalono, iż na torfowiskach dużych (śr. 2 524 ha) łąki niekoszone i częściowo zakrzewione zajmują 23,3% ich powierzchni na obiektach średnich (śr. 34 ha) - 10,2% i małych (śr. 8,4 ha) - 10,7%. Udział powierzchni gruntów ornych w tych grupach torfowisk odpowiednio: 2,4, 6,7 i 18%. W dolinach rzek Cybina i Główna zmiany sposobu użytkowania są największe. Wynikają one z wyłączenia z użytkowania dużej powierzchni podmokłych łąk, pokrytych obecnie szuwarami trzcinowymi i rzadkimi zadrzewieniami, oraz z budowy dużego zbiornika retencyjnego. Wykazano małą przydatność archiwalnych zdjęć lotniczych i satelitarnych do określenia aktualnego sposobu użytkowania torfowisk.The objective of studies carried out in 2002 was to determine changes in the peatland use in Poznań region. The studies included 124 peatlands covering a total area of 4000 ha. The work was accomplished by field studies and by interpretation of aerial and satellite images using graphical computer programmes to determine particular areas. The following land use types were distinguished: meadows mown once, meadows mown twice, not mown meadows, meadows with shrubs, extensive pastures, reed rushes, stagnant waters, arable lands, forests and thickets. Significant changes in the land use were found when geological documentation of peatlands made in the years 1957-1969, aerial photographs (1993-1998) and satellite images (1989-1991) were compared. Apart from the mentioned studies, earlier publications were used (Ilnicki, 2002) when formulating conclusions . It was found that on large peatlands (mean area 2524 ha), not mown meadows and meadows partially covered by shrubs occupied 23.3 % of the total area; in medium size objects (34 ha) and in small peatlands (8.4 ha) they covered 10.2 and 10.7 %, respectively. The share of arable land increased from 2.4 to 6.7 and 18 %, respectively. In the valleys of the Cybina and Główna rivers, the changes in land use were the greatest. They resulted from abandoned land use on large areas of wet meadows, currently covered by reed rushes and thickets and from the construction of a large retention reservoir. The archival aerial and satellite photographs proved to be of little value for the determination of peatland use

Patterns of Hospital Bypass and Interhospital Transfer Among Patients With Heart Failure.

BACKGROUND: We describe how patient characteristics influence hospital bypass, interhospital transfer, and in-hospital mortality in patients with heart failure in Washington. Rural patients with heart failure may bypass their nearest hospital or be transferred for appropriate therapies. The frequency, determinants, and outcomes of these practices remain uncharacterized. METHODS AND RESULTS: Mean excess travel times based on hospital and patient residence ZIP codes were calculated using published methods. Hospitals and servicing areas were coded based on bed size and ZIP code, respectively. Transfer patterns were analyzed using bootstrap inference for clusters. Analysis of mortality and transfer-associated factors was performed using logistic regression with generalized estimating equations. There were 48,163 patients, representing 1106 instances of transfer, studied. The mean excess travel time increased 7.14 minutes per decrease in population density (metropolitan, micropolitan, small town, rural; P \u3c .0001). The rural mean excess travel time was greatest at 28.56 minutes. Transfer likelihood increased with younger age, male gender, admitting hospital rurality, higher Charlson Comorbidity Index, and stroke. Transfer was less likely among women (odds ratio [OR], 0.82; 95% confidence interval [CI], 0.72-0.94) and patients over 70 years old (OR, 0.15-0.46; 95% CI, 0.10-0.65). Adjusting for comorbidities and transfer propensity, transfer exhibited a stronger association with mortality than any other measured patient risk factor (OR, 2.15; 95% CI, 1.69-2.73), excluding stroke (OR, 7.09; 95% CI, 4.99-10.06). CONCLUSIONS: Rural hospital bypass is prevalent among patients with heart failure, although its clinical significance is unclear. Female and older patients were found to have a lesser likelihood of transfer adjusted for other factors. Interhospital transfer is associated with increased mortality when adjusted for comorbidities

Feasibility Study of a Temporary Percutaneous Left Ventricular Assist Device in Cardiac Surgery

Background: The aim of this study is to evaluate a percutaneous left ventricular assist device (Tandem Heart pVAD; Cardiac Assist, Pittsburgh, Pennsylvania) in the postcardiotomy setting. Methods: Between August 2001 and August 2004, 11 high-risk male patients who had undergone heart failure surgery or surgical revascularization were supported by the TandemHeart postcardiotomy. The major indication for pVAD insertion was failure to wean from cardiopulmonary bypass. Three different techniques were employed for cannulation: the closed percutaneous technique, the "open transeptal" technique with percutaneous cannulas insertion, and direct central cannulation. Results: The mean duration of support was 88 hours. The mean pump flow was 3.09 L/min. The weaning rate was 72.72%. Survival to discharge and at 1 and 4 years was 54.54%, 45.45%, and 36.36%, respectively. The main complication was pericardial bleeding, noted mainly in patients receiving antiplatelet treatment preoperatively. Conclusions: The TandemHeart appears to be safe for temporary support after cardiotomy. It is a versatile device allowing different techniques of insertion. Device application yielded high weaning rate and satisfactory early and long-term survival. © 2007 The Society of Thoracic Surgeons

Long-term adult congenital heart disease survival after heart transplantation: A restricted mean survival time analysis.

BACKGROUND: Adult Congenital Heart Disease (ACHD) heart transplant recipients may have lower post-transplant survival resulting from higher peri-operative mortality than non-ACHD patients. However, the late risk of mortality appears lower in ACHD recipients. This study seeks to establish whether long-term heart transplant survival is reduced among ACHD recipients relative to non-ACHD recipients. METHODS: Adult patients who received a heart transplant between January, 2000 and December, 2019 in the United Network for Organ Sharing database were stratified by the presence of ACHD. Propensity-matched cohorts (1:4) were created to adjust for differences between groups. Graft survival at time points from 1 to 18 years was compared between groups using restricted mean survival time (RMST) analysis. RESULTS: The matched cohort included 1,139 ACHD and 4,293 non-ACHD patients. Median age was 35 years and 61% were male. Average survival time at 1 year was 0.85 years for ACHD patients and 0.93 years for non-ACHD patients (average difference: -0.08 years, 95% Confidence Interval [CI] -0.10 to -0.06, p \u3c 0.001), reflecting higher immediate post-transplant mortality. Average survival time at 18 years was not clinically or statistically different: 11.14 years for ACHD patients and 11.40 years for non-ACHD patients (average difference: -0.26 years, 95% CI: -0.85 to + 0.32 years, p = 0.38). CONCLUSIONS: Despite increased medium-term mortality among ACHD patients after heart transplant, differences in long-term survival are minimal. Allocation of hearts to ACHD patients results in acceptable utility of donor hearts