Journal of Heart and Lung Transplantation最新文献

Xenotransplant covers a broad ethical territory and there are several ethical questions that have arisen in parallel with the technological advances that have allowed the first porcine transplants to occur. This brief communication highlights ethical considerations regarding heart and lung xenotransplantation, with an emphasis on unresolved value-based concerns in the field. The aim of this text is therefore to encourage the readers to consider the vast potential of this emerging technique to do good, but also the risk of doing harm, and to participate in a discussion. The list of questions presented here is not exhaustive but hopefully represents some of the questions that appear to be most pressing as the field advances. The focus is on the value-based, or ethical questions, not the questions related to the practical medical procedures.

Background

The quality-adjusted life year (QALY) measures disease burden and treatment, combining overall survival and health-related quality of life (HRQOL). We estimated QALYs in 3 groups of older patients (60-80 years) with heart failure (HF) who underwent heart transplantation (HT, with pre-transplant mechanical circulatory support [HT MCS] or HT without pre-transplant MCS [HT Non-MCS]) or long-term MCS (destination therapy). We also identified factors associated with gains in QALYs through 24 months follow-up.

Methods

Of 393 eligible patients enrolled (10/1/15-12/31/18) at 13 U.S. sites, 161 underwent HT (n = 68 HT MCS, n = 93 HT Non-MCS) and 144 underwent long-term MCS. Survival and HRQOL data were collected through 24 months. QALY health utilities were based on patient self-report of EQ-5D-3L dimensions. Mean-restricted QALYs were compared among groups using generalized linear models.

Results

For the entire cohort, mean age in years closest to surgery was 67 (standard deviation, SD: 4.7), 78% were male, and 83% were White. By 18 months post-surgery, sustained significant differences in adjusted average ± SD QALYs emerged across groups, with the HT Non-MCS group having the highest average QALYs (24-month window: HT Non-MCS = 22.58 ± 1.1, HT MCS = 19.53 ± 1.33, Long-term MCS = 19.49 ± 1.3, p = 0.003). At 24 months post-operatively, a lower gain in QALYs was associated with HT MCS, long-term MCS, a lower pre-operative LVEF, NYHA class III or IV before surgery, and an ischemic or other etiology of HF.

Conclusions

Determination of QALYs may provide important information for policy makers and clinicians to consider regarding benefits of HT and long-term MCS as treatment options for older patients with HF.

Background

Few studies highlighting the critical care management of patients after heart HTx (HTx) have been published to date. This analysis provides a contemporary representation of pre- and post-HTx critical care in various patient cohorts and outlines the impact of intensive care unit (ICU) therapies on outcomes.

Methods

Data from PC4 Collaborative Registry were analyzed for pediatric patients undergoing HTx between August 2014 and April 2022.

Results

A total of 1877 HTx in 1857 patients were reported from 42 centers; 56.5% had congenital heart disease (CHD). Patients with CHD were younger, smaller, more likely male, White race, and publicly insured. CHD patients had higher need for catheterization, increased likelihood of inotropic support and mechanical ventilation and lower VAD rates. Their operative courses were significant for longer bypass and cross-clamp times. Postoperatively, CHD patients required more CPR , utilized more ICU therapies and had higher hospital mortality (7.8% vs. 1.8% for non-CHD patients, p<0.0001). Longer cardiopulmonary bypass, longer deep hypothermic circulatory arrest times and delayed sternal closure were independent risk factors for hospital mortality. Lastly, center transplant volume but not surgical volume was associated with transplant outcomes.

Conclusions

A diagnosis of CHD before HTx is associated with a greater use of ICU-specific therapies compared non-CHD cohort. Operative factors, particularly in patients with CHD, are independently associated with higher hospital mortality as was low transplant volume at the center. The study provides basis for further investigating ICU and operative factors that can be modified to improve transplant outcomes.

It is unknown whether racial disparities in access to heart transplantation (HT) are amplified when coupled with substance use. We examined patients evaluated for HT over 8 years at an urban transplant center. We evaluated substance use and race/ethnicity as independent and interactive predictors of HT and left ventricular assist device (LVAD) implantation. Of 1,148 patients evaluated for HT, substance use was cited as an ineligibility factor in 151 (13%) patients, 16 (11%) of whom ultimately received HT. Significantly more non-Hispanic Black (NHB) patients were deemed ineligible due to substance use (n = 59, 19%) compared to other races/ethnicities (non-Hispanic white: n = 68, 12%; other race/ethnicity: n = 24, p = 0.002). No racial differences were observed in the likelihood of HT among patients initially excluded for substances, but more NHB patients ultimately received LVAD than the other racial groups. This study encourages greater awareness of the role of substance use and race in the HT evaluation.

Background

Some patients with chronic thromboembolic pulmonary hypertension (CTEPH) exhibit exercise intolerance due to reduced cardiac output (CO) even after successful balloon pulmonary angioplasty (BPA). Medical therapy is a potential option for such cases; however, it is unclear which patients necessitate it even after BPA.

Methods

This study included 286 patients with CTEPH who underwent BPA and right heart catheterization 1 year after the final BPA and classified them into no-medication and withdrawal groups. The no-medication group comprised patients without pulmonary hypertension (PH) medications before and after BPA, while the withdrawal group included patients who received PH medications before BPA and discontinued them after BPA. We assessed differences in the changes in CO after BPA from baseline (ΔCO) between the 2 groups. Additionally, we evaluated the ΔCO among different age categories within each group: younger (<60 years), middle-aged (60-70 years), and older adults (≥70 years).

Results

After adjusting baseline covariates, overall CO did not differ significantly. However, ΔCO was significantly positive in the no-medication group but negative in the withdrawal group (0.32 and −0.33, difference in ΔCO: −0.65, 95% confidence intervals: −0.90 to −0.40). A significantly positive effect on ΔCO was observed in younger and middle-aged individuals, with a significant interaction between age and ΔCO in no-medication groups.

Conclusions

Increasing CO with BPA alone may be challenging with age in patients with CTEPH. Given that discontinuation of PH medication after BPA decreased CO more than the effect of BPA, medical therapy might be necessary even after successful BPA.

Background

Molecular testing with gene-expression profiling (GEP) and donor-derived cell-free DNA (dd-cfDNA) is increasingly used in the surveillance for acute cellular rejection (ACR) after heart transplant. However, the performance of dual testing over each test individually has not been established. Further, the impact of dual noninvasive surveillance on clinical decision-making has not been widely investigated.

Methods

We evaluated 2,077 subjects from the Surveillance HeartCare Outcomes Registry registry who were enrolled between 2018 and 2021 and had verified biopsy data and were categorized as dual negative, GEP positive/dd-cfDNA negative, GEP negative/dd-cfDNA positive, or dual positive. The incidence of ACR and follow-up testing rates for each group were evaluated. Positive likelihood ratios (LRs+) were calculated, and biopsy rates over time were analyzed.

Results

The incidence of ACR was 1.5% for dual negative, 1.9% for GEP positive/dd-cfDNA negative, 4.3% for GEP negative/dd-cfDNA positive, and 9.2% for dual-positive groups. Follow-up biopsies were performed after 8.8% for dual negative, 14.2% for GEP positive/dd-cfDNA negative, 22.8% for GEP negative/dd-cfDNA positive, and 35.4% for dual-positive results. The LR+ for ACR was 1.37, 2.91, and 3.90 for GEP positive, dd-cfDNA positive, and dual-positive testing, respectively. From 2018 to 2021, biopsies performed between 2 and 12-months post-transplant declined from 5.9 to 5.3 biopsies/patient, and second-year biopsy rates declined from 1.5 to 0.9 biopsies/patient. At 2 years, survival was 94.9%, and only 2.7% had graft dysfunction.

Conclusions

Dual molecular testing demonstrated improved performance for ACR surveillance compared to single molecular testing. The use of dual noninvasive testing was associated with lower biopsy rates over time, excellent survival, and low incidence of graft dysfunction.

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.

Background

Sarcopenia, characterized by loss of muscle mass and function, is prevalent in heart failure (HF) and predicts poor outcomes. We investigated alterations in sarcopenia index (SI), a surrogate for skeletal muscle mass, in HF, left ventricular assist device (LVAD), and heart transplant (HT), and assessed its relationship with inflammation and digestive tract (gut and oral) microbiota.

Methods

We enrolled 460 HF, LVAD, and HT patients. Repeated measures pre/post-procedures were obtained prospectively in a subset of LVAD and HT patients. SI (serum creatinine/cystatin C) and inflammatory biomarkers (C-reactive protein, interleukin-6, tumor necrosis factor-alpha) were measured in 271 and 622 blood samples, respectively. Gut and saliva microbiota were assessed via 16S ribosomal ribonucleic acid sequencing among 335 stool and 341 saliva samples. Multivariable regression assessed the relationship between SI and (1) New York Heart Association class; (2) pre- versus post-LVAD or HT; and (3) biomarkers of inflammation and microbial diversity.

Results

Median (interquartile range) natural logarithm (ln)-SI was −0.13 (−0.32, 0.05). Ln-SI decreased across worsening HF class, further declined at 1 month after LVAD and HT, and rebounded over time. Ln-SI was correlated with inflammation (r = −0.28, p < 0.01), gut (r = 0.28, p < 0.01), and oral microbial diversity (r = 0.24, p < 0.01). These associations remained significant after multivariable adjustment in the combined cohort but not for all individual cohorts. The presence of the gut taxa Roseburia inulinivorans was associated with increased SI.

Conclusions

SI levels decreased in symptomatic HF and remained decreased long-term after LVAD and HT. In the combined cohort, SI levels covaried with inflammation in a similar fashion and were significantly related to overall microbial (gut and oral) diversity, including specific taxa compositional changes.

Left ventricular assist devices (LVADs) are excellent therapies for advanced heart failure patients either bridged to transplant or for lifetime use. LVADs also allow for reverse remodeling of the failing heart that is often associated with functional improvement. Indeed, growing enthusiasm exists to better understand this population of patients, whereby the LVAD is used as an adjunct to mediate myocardial recovery. When patients achieve benchmarks suggesting that they no longer need LVAD support, questions related to the discontinuation of LVAD therapy become front and center. The purpose of this review is to provide a surgical perspective on the practical and technical issues surrounding LVAD deactivation.