ABSTRACT
BACKGROUND: Previous studies have demonstrated an association between transplantation rate per center and postoperative mortality after heart transplantation. In 2011, Sweden centralized heart transplants and waiting lists, reducing the number of centers from 3 to 2. We aimed to assess the active waiting time and pre- and post-transplant mortality before and after centralization. METHODS: Heart transplantations performed in Sweden between January 1, 2001 and December 31, 2020 were included. Background and donor organ supply data were collected from Scandiatransplant, the Swedish Thoracic Transplant Registry, and the Swedish Cardiac Surgery Registry. The Fine and Gray methods were applied to visualize cumulative incidence curves and conduct competing risk regressions. A Cox model was used to adjust for factors influencing time to post-transplant death. RESULTS: When comparing the two eras, the median active waiting time increased from 54 to 71 days (p = 0.015). The risk of mortality on the waiting list decreased in the later era (subhazard ratio 0.43; [95% confidence interval {CI} 0.25-0.74]; p = 0.002). The number of heart transplantation procedures (including pediatric patients) increased by 53%. There was a significant difference in organ utilization between eras (p = 0.033; chi-square test). 30-day and 1-year survival post-transplant rates for adults increased from 90.8% to 97.8% (p < 0.001) and from 87.9% to 94.6% (p < 0.001), respectively. 1-year mortality was reduced by 63% (hazard ratio 0.37; 95% CI 0.22-0.61). CONCLUSIONS: This nationwide study examined patients listed for and undergoing heart transplantation before and after the centralization of waiting lists and surgeries in Sweden. Waiting list mortality decreased, and 1-year post-transplantation survival was improved.
ABSTRACT
OBJECTIVES: Our aim was to derive, based on the SWEDEHEART registry, and validate, using the Western Denmark Heart registry, a patient-oriented risk score, the SweDen score, which could calculate the risk of 1-year mortality following a myocardial infarction (MI). METHODS: The factors included in the SweDen score were age, sex, smoking, diabetes, heart failure and statin use. These were chosen a priori by the SWEDEHEART steering group based on the premise that the factors were information known by the patients themselves. The score was evaluated using various statistical methods such as time-dependent receiver operating characteristics curves of the linear predictor, area under the curve metrics, Kaplan-Meier survivor curves and the calibration slope. RESULTS: The area under the curve values were 0.81 in the derivation data and 0.76 in the validation data. The Kaplan-Meier curves showed similar patient profiles across datasets. The calibration slope was 1.03 (95% CI 0.99 to 1.08) in the validation data using the linear predictor from the derivation data. CONCLUSIONS: The SweDen risk score is a novel tool created for patient use. The risk score calculator will be available online and presents mortality risk on a colour scale to simplify interpretation and to avoid exact life span expectancies. It provides a validated patient-oriented risk score predicting the risk of death within 1 year after suffering an MI, which visualises the benefit of statin use and smoking cessation in a simple way.
