Influence of Transplant Center Procedural Volume on Survival Outcomes of Heart Transplantation for Children Bridged with Mechanical Circulatory Support

Health Disparities in Extracorporeal Membrane Oxygenation Utilization and Outcomes: A Scoping Review and Methodologic Critique of the Literature

OBJECTIVES

To map the scope, methodological rigor, quality, and direction of associations between social determinants of health (SDoH) and extracorporeal membrane oxygenation (ECMO) utilization or outcomes.

DATA SOURCES

PubMed, Web of Science, Embase, and Cochrane Library databases were systematically searched for citations from January 2000 to January 2023, examining socioeconomic status (SES), race, ethnicity, hospital and ECMO program characteristics, transport, and geographic location (context) with utilization and outcomes (concept) in ECMO patients (population).

STUDY SELECTION

Methodology followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses scoping review extension. Two reviewers independently evaluated abstracts and full text of identified publications. Exclusion criteria included non-English, unavailable, less than 40 patients, and periprocedural or mixed mechanical support.

DATA EXTRACTION

Content analysis used a standardized data extraction tool and inductive thematic analysis for author-proposed mediators of disparities. Risk of bias was assessed using the Quality in Prognosis Studies tool.

DATA SYNTHESIS

Of 8,214 citations screened, 219 studies were identified. Primary analysis focuses on 148 (68%) including race/ethnicity/SES/payer variables including investigation of ECMO outcomes 114 (77%) and utilization 43 (29%). SDoH were the primary predictor in 15 (10%). Overall quality and methodologic rigor was poor with advanced statistics in 7%. Direction of associations between ECMO outcomes or utilization according to race, ethnicity, SES, or payer varied. In 38% adverse outcomes or lower use was reported in underrepresented, under-resourced or diverse populations, while improved outcomes or greater use were observed in these populations in 7%, and 55% had no statistically significant result. Only 26 studies (18%) discussed mechanistic drivers of disparities, primarily focusing on individual- and hospital-level rather than systemic/structural factors.

CONCLUSIONS

Associations between ECMO utilization and outcomes with SDoH are inconsistent, complicated by population heterogeneity and analytic shortcomings with limited consideration of systemic contributors. Findings and research gaps have implications for measuring, analyzing, and interpreting SDoH in ECMO research and healthcare.

Impact of interhospital transfer on clinical outcomes and costs of extracorporeal life support

BACKGROUND

The impact of interhospital transfers for extracorporeal life support have not been studied in large datasets. The present study sought to determine the impact of such patient transfers on survival, complications, and hospitalization costs.

METHODS

The 2010 to 2016 database of the National Inpatient Sample was used to identify all adults who underwent extracorporeal life support. Patients were categorized based on whether or not they were transferred to another facility. Trend analysis and multivariable models were used to characterize the impact of inter hospital transfer on in-hospital mortality, complications, duration of stay, and costs.

RESULTS

Of an estimated 29,298 extracorporeal life support hospitalizations during the study period, 36.8% were transferred from an outside facility. Extracorporeal life support hospitalizations experienced a 7-fold increase with no difference in mortality between transferred and not transferred cohorts in 2016 (4.79% vs 4.79%, P = .97). Mortality rates were less for patients transferred to high volume centers compared to low volume hospitals (48.7% vs 51.6%, P < .001). Transfer to a low volume hospital for cardiogenic shock was associated with greater odds of mortality (adjusted odds Rratio: 2.25, confidence interval 1.01-5.03).

CONCLUSION

Utilization of extracorporeal life support in both transferred and not transferred patients has statistically significantly increased with a decrement in mortality for those transferred. Survival in the transferred cohort is strongly associated with extracorporeal life support procedure volume of the center and this must be taken into account when considering extracorporeal life support transfer.

Impact of mechanical circulatory support on survival in pediatric heart transplantation

Evidence on the impact of MCS on pediatric heart transplant survival is still scarce related to congenital heart disease patients including univentricular physiology as well as the risk factors for complications. We performed a retrospective review of all urgent pediatric (aged ≤16 years) HT from 2004 to 2014 in the Spanish Pediatric Heart Transplant Registry Group. Patients were stratified into two groups: urgent 0 (MCS at HT) and urgent 1 (non-MCS at HT). The primary outcome measure was post-transplant survival; secondary outcome measures were complications and absence of infections and rejection during the first post-transplant year. One hundred twenty-one pediatric patients underwent urgent HT, 58 (47.9%) urgent 0 and 63 (52%) urgent 1. There were 30 (24.8%) deaths: 12 in the urgent 0 group and 18 in the urgent 1 group, P = n.s. Regarding the type of MCS, patients on ECMO had the highest rate of complications (80%) and mortality (40%). Patients in the urgent 1 group showed a higher risk of hospital re-admission for infection during the first year after transplantation (OR 2.31 [1.1-4.82]), P = .025. We did not identify a risk factor for mortality. MCS does not impact negatively on survival after HT. However, there is a significant increase in 30-day and 1-year mortality and complications in ECMO patients compared with VAD patients. Infants, congenital heart disease, and PediMACS were not found to be risk factors for mortality.

Motor outcome, executive functioning, and health-related quality of life of children, adolescents, and young adults after ventricular assist device and heart transplantation

OBJECTIVE

The aim of the current study is to measure long-term executive function, motor outcome, and QoL in children, adolescents, and young adults after VAD and Htx.

METHODS

Patients were examined during routine follow-up. Investigation tools were used as follows: Examination for MND of motor outcomes, Epitrack^® for attention and executive functioning, and Kidscreen-52 and EQ-5D-5L questionnaires for QoL. Additional data were retrospectively obtained by an analysis of patient medical records.

RESULTS

Out of 145 heart transplant recipients at the department of pediatric cardiology of the University Hospital Munich, 39 were implanted with a VAD between 1992 and 2016. Seventeen (43.6%) patients died before or after Htx; 22 (56.4%) patients were included in our study. Mean age at transplant was 9.52 years (range: 0.58-24.39 years, median 9), and the mean follow-up time after Htx was 6.18 years (range: 0.05-14.60 years, median 5.82). MND examination could be performed in 13 patients (normal MND: n = 11, simple MND: n = 1, complex MND: n = 1). Executive functioning was tested in 15 patients. Two (13.3%) patients had good results, six (40%) average results, three (20%) borderline results, and four (26.7%) impaired results. QoL (Kidscreen n = 7, EQ-5D-5L n = 8) was similar to a healthy German population.

CONCLUSION

Motor outcome, executive functioning and QoL in survivors of VAD bridging therapy and Htx can be good, though underlying diseases and therapies are associated with a high risk of cerebral ischemic or hemorrhagic complications.

Age-Dependent Impact of Pre-Transplant Intensive Care Unit Stay on Mortality in Heart Transplant Recipients

Background

Heart transplantation (HTx) is a treatment option for refractory end-stage heart failure. Severe illness requiring pre-transplant intensive care unit (ICU) stay may be a risk factor for diminished post-transplant survival, but this association is surprisingly inconsistent in recent studies. To clarify the significance of ICU stay as a risk factor for heart transplant outcomes, we aimed to define if patient age was a factor in which ICU stay was predictive of survival after HTx.

Methods

De-identified data were obtained on isolated first-time HTx performed during the years 2006 - 2015 from the UNOS Registry. Nine age groups were defined. The primary outcome was 1-year post-transplant mortality. Cox proportional hazard regression estimated unadjusted and adjusted hazard ratio (HR) associated with pre-transplant ICU stay in each age group.

Results

The analysis included 19,508 patients (9% deceased within 1 year). In the overall cohort, pre-transplant ICU stay was associated with increased hazard of 1-year mortality (HR = 1.3; 95% confidence interval (CI): 1.2 - 1.4; P < 0.001); but further univariate analysis showed a greater hazard of 1-year mortality associated with ICU stay in infants (HR = 2.2; 95% CI: 1.5 - 3.2; P < 0.001). However, the adjusted analysis found that adults ages 40 - 49 had the highest statistically significant hazard of 1-year mortality (HR = 1.5; 95% CI: 1.1 - 2.1; P = 0.011).

Conclusions

Our study established age variation in the association between ICU stay and survival after HTx, with this association being strongest among adults, 40 to 49 years of age, undergoing HTx. Previous data suggesting decreased survival in infants may be related to the increased use of extracorporeal membrane oxygenation as a mechanical cardiac assist rather than ventricular assist devices.