Perioperative mortality is the Achilles heel for cardiac transplantation in adults with congenital heart disease: Evidence from analysis of the UNOS registry

Caring for the Critically Ill Adult Congenital Heart Disease Patient

PURPOSE OF REVIEW

This review aims to discuss the unique challenges that adult congenital heart disease (ACHD) patients present in the intensive care unit.

RECENT FINDINGS

Recent studies suggest that ACHD patients make up an increasing number of ICU admissions, and that their care greatly improves in centers with specialized ACHD care. Common reasons for admission include arrhythmia, hemorrhage, heart failure, and pulmonary disease. It is critical that the modern intensivist understand not only the congenital anatomy and subsequent repairs an ACHD patient has undergone, but also how that anatomy can predispose the patient to critical illness. Additionally, intensivists should rely on a multidisciplinary team, which includes an ACHD specialist, in the care of these patients.

Survival After Cardiac Transplantation in Adults With Single-Ventricle Congenital Heart Disease

BACKGROUND

Without large-scale analyses of adults with single-ventricle congenital heart disease (CHD) undergoing heart transplantation, little evidence exists to guide listing practices and patient counseling.

OBJECTIVES

This study aims to evaluate survival after heart transplantation in adults with single and biventricular CHD and compare it to that of non-CHD transplant recipients.

METHODS

In this 15-year (2005-2020) retrospective analysis, outcome-blinded investigators used probability-linkage to merge the National (Nationwide) Inpatient Sample and Organ Procurement and Transplantation Network data sets.

RESULTS

Of 382 adult (≥18 years of age) heart transplant recipients with CHD, 185 (48%) had single-ventricle physiology. Compared to biventricular CHD, single-ventricle patients showed significantly reduced survival at 1 (80% vs 91%; HR: 2.50; 95% CI: 1.40-4.49; P = 0.002) and 10 years (54% vs 71%; HR: 2.10; 95% CI: 1.38-3.18; P < 0.001). Among patients who survived the first post-transplantation year, biventricular CHD patients exhibited similar 10-year survival as single-ventricle patients, except for those with hypoplastic left heart syndrome (79% vs 71%; HR: 1.58; 95% CI: 0.85-2.92; P = 0.15). Additionally, biventricular CHD transplant recipients showed significantly better 10-year conditional survival compared to their non-CHD counterparts (79% vs 68%; HR: 0.73; 95% CI: 0.59-0.90; P = 0.003).

CONCLUSIONS

Among adult CHD transplant recipients, single-ventricle physiology correlated with higher short-term mortality. However, 10-year conditional survival was similar for biventricular and most single-ventricle CHD patients, and notably better for biventricular CHD patients compared to non-CHD heart transplant recipients. These findings have significant implications towards patient selection and listing strategies, easing concerns related to heart transplantation in adults with CHD and destigmatizing most subtypes of single-ventricle CHD.

Overview of Long-Term Outcome in Adults with Systemic Right Ventricle and Transposition of the Great Arteries: A Review

The population of patients with a systemic right ventricle (sRV) in biventricular circulation includes those who have undergone an atrial switch operation for destro-transposition of the great arteries (d-TGA) and those with congenitally corrected transposition of the great arteries (ccTGA). Despite the life expectancy of these patients is significantly increased, the long-term prognosis remains suboptimal due to late complications such as heart failure, arrhythmias, and premature death. These patients, therefore, need a close follow-up to early identify predictive factors of adverse outcomes and to implement all preventive therapeutic strategies. This review analyzes the late complications of adult patients with an sRV and TGA and clarifies which are risk factors for adverse prognosis and which are the therapeutic strategies that improve the long-term outcomes. For prognostic purposes, it is necessary to monitor sRV size and function, the tricuspid valve regurgitation, the functional class, the occurrence of syncope, the QRS duration, N-terminal pro B-type natriuretic peptide levels, and the development of arrhythmias. Furthermore, pregnancy should be discouraged in women with risk factors. Tricuspid valve replacement/repair, biventricular pacing, and implantable cardioverter defibrillator are the most important therapeutic strategies that have been shown, when used correctly, to improve long-term outcomes.

Continuous-Flow Ventricular Assist Device Support in Adult Congenital Heart Disease: A 15-Year, Multicenter Experience of Temporary and Durable Support

Heart failure (HF) is common in adult congenital heart disease (ACHD) patients; however, use of continuous-flow ventricular assist devices (CF-VADs) remains rare. We reviewed outcomes of patients with congenital heart disease greater than or equal to 18 years of age at the time of CF-VAD implant at the affiliated pediatric and adult institutions between 2006 and 2020. In total, 18 ACHD patients (15 with great anatomical complexity) received 21 CF-VADs. Six patients (median age 34 years) received seven percutaneous CF-VADs with a median duration of support of 20 days (3-44 days) with all patients survived to hospital discharge and two patients were bridged to durable CF-VADs. Fourteen patients (median age 38 years) received durable CF-VADs. Thirteen patients (93%) survived to hospital discharge and the median duration of support was 25.8 months (6.4-52.1 months). Estimated survival on durable CF-VAD at 1, 3, and 5 years was 84%, 72%, and 36%, respectively. Three patients were successfully bridged to transplantation. Device-related complications include cerebrovascular accident (n = 5), driveline infection (n = 3), device infection requiring chronic antibiotic therapy (n = 4), gastrointestinal bleeding (n = 6), and presumed pump thrombosis (n = 5). These results show percutaneous and durable CF-VADs can support ACHD patients with advanced HF.

The Cost-effectiveness of Transplanting Hearts From Hepatitis C-infected Donors Into Uninfected Recipients

BACKGROUND

The DONATE HCV trial demonstrated the safety and efficacy of transplanting hearts from hepatitis C viremic (HCV+) donors. In this report, we examine the cost-effectiveness and impact of universal HCV+ heart donor eligibility in the United States on transplant waitlist time and life expectancy.

METHODS

We developed a microsimulation model to compare 2 waitlist strategies for heart transplant candidates in 2018: (1) status quo (SQ) and (2) SQ plus HCV+ donors (SQ + HCV). From the DONATE HCV trial and published national datasets, we modeled mean age (53 years), male sex (75%), probabilities of waitlist mortality (0.01-0.10/month) and transplant (0.03-0.21/month) stratified by medical urgency, and posttransplant mortality (0.003-0.052/month). We assumed a 23% increase in transplant volume with SQ + HCV compared with SQ. Costs (2018 United States dollar) included waitlist care ($2200-190 000/month), transplant ($213 400), 4-wk HCV treatment ($26 000), and posttransplant care ($2500-11 300/month). We projected waitlist time, quality-adjusted life-years (QALYs), lifetime costs, and incremental cost-effectiveness ratios (ICERs [$/QALY, discounted 3%/year]; threshold ≤$100 000/QALY).

RESULTS

Compared with SQ, SQ + HCV decreased waitlist time from 8.7 to 6.7 months, increased undiscounted life expectancy from 8.9 to 9.2 QALYs, and increased discounted lifetime costs from $671 400/person to $690 000/person. Four-week HCV treatment comprised 0.5% of lifetime costs. The ICER of SQ + HCV compared with SQ was $74 100/QALY and remained ≤$100 000/QALY with up to 30% increases in transplant and posttransplant costs.

CONCLUSIONS

Transplanting hearts from HCV-infected donors could decrease waitlist times, increase life expectancy, and be cost-effective. These findings were robust within the context of current high HCV treatment costs.

Heart Failure in Complex Congenital Heart Disease of the Adult

PURPOSE OF REVIEW

Adult congenital heart disease (ACHD) patients have demonstrated improved survival, especially those with severely complex disease, mainly single-ventricle/Fontan physiology and those with a systemic right ventricle. We describe the heart failure phenotypes of complex CHD, reversible causes for heart failure, and considerations for advanced therapy.

RECENT FINDINGS

While initially marketed for application to patients with acquired causes for heart failure, newer devices and technologies have started to be used in the ACHD population. After reversible causes for heart failure in CHD are addressed, it is reasonable to consider use of new device-based technologies and orthotopic heart transplant (OHT) for end-stage disease. New heart failure technology and organ transplant should carefully be considered and applied in complex ACHD, where there may be significant improvement in morbidity and mortality.

Impact of the new UNOS donor heart allocation system on waitlist outcomes and early posttransplant mortality among adults with congenital heart disease

Adults with congenital heart disease (ACHD) experience worse waitlist outcomes and higher early posttransplant mortality compared to non-ACHD patients. On October 18, 2018; the UNOS donor heart allocation system was redesigned giving unique listing status to ACHD patients. The impact of this change on outcomes in transplant-listed patients is unstudied. Using the Scientific Registry of Transplant Recipients (SRTR) we compared ACHD patients listed for the first-time for heart transplantation from two eras of equal duration. We analyzed waitlist outcomes, posttransplant mortality and length of stay among ACHD patients in both eras and between ACHD and non-ACHD patients in the new era. Of 12 723 listed patients, 535 had ACHD (293 in the new era) and 12 188 did not (6258 in the new era). A total of 163 (56%) ACHD patients in the new era versus 150 (62%) in the prior era were transplanted; 11 (3.8%) versus 15 (6.2%) died on the waitlist; 32 (11%) versus 35 (14%) were delisted and 15 (9.2%) versus 19 (12.7%) died within 30 days of transplant, respectively. The new UNOS donor heart allocation system improved waitlist time and decreased the proportion not transplanted during the first 300 days after listing among ACHD patients without altering early posttransplant outcomes or significantly changing the gap in outcomes compared to non-ACHD patients.

Current opinion in pediatric heart transplantation

PURPOSE OF REVIEW

Cardiac transplant remains the most effective therapy for children with end-stage heart disease. Outcomes remain better than any alternative therapy for this condition, but its use is limited by donor organ availability. As a result, waitlist times and mortality on the waiting list remain unacceptably high. Novel approaches are necessary to address this problem.

RECENT FINDINGS

Organ Procurement and Transplant Network/United Network for Organ Sharing readjusted the pediatric heart allocation system in 2016 to prioritize children at highest risk of mortality, encourage judicious listing, and improve appropriate donor organ utilization. Subsequent studies have aligned with these priorities to help risk-stratify patients at the time of listing and identify the importance that should be assigned to donor-specific factors. In addition, many authors are advocating for increased utilization of hearts donated after cardiac death. Pediatric Ventricular Assist Device (VAD) application has also been increasing to help decrease waitlist mortality. Although results have significantly improved, there remain important limitations to widespread use of VADs in the pediatric population. This has prompted novel techniques such as pulmonary artery banding to improve cardiac function and, in some cases, promote recovery. The demand for cardiac replacement continues to increase with an ageing population of patients with congenital heart disease, presenting new challenges and stressors to the system.

SUMMARY

Pediatric cardiac transplant outcomes are excellent but remain plagued by the limited supply of donor organs. Recent strategies to combat this problem have focused on judicious listing, maximal utilization of available donor organs, and safely extending the lives of patients on the waitlist. New demands on the organ supply chain will continue to stress the system, making these efforts of the highest importance.Clinical Trial Registry Number not applicable.

Cardiac transplantation in adult congenital heart disease with prior sternotomy

BACKGROUND

Adult congenital heart disease (ACHD) patients who require orthotopic heart transplantation are surgically complex due to anatomical abnormalities and multiple prior surgeries. In this study, we investigated these patients' outcomes using our institutional database.

METHODS

ACHD patients who had prior intracardiac repair and subsequent heart transplant were included (2008-2018). Adult patients without ACHD were extracted as a control. A comparison of patients with functional single ventricular (SV) and biventricular (BV) hearts was performed.

RESULTS

There were 9 SV and 24 BV patients. The SV group had higher central venous pressure/pulmonary capillary wedge pressure (P = .028), hemoglobin concentration (P = .010), alkaline phosphatase (P = .022), and were more likely to have liver congestion (P = .006). Major complications included infection in 16 (48.5%), temporary dialysis in 12 (36.4%), and graft dysfunction requiring perioperative mechanical support in 7 (21.2%). Overall in-hospital mortality was 15.2%. Kaplan-Meier analysis showed a higher, but not statistically significant, survival after 10 years between the ACHD and control groups (ACHD 84.9% vs. control 67.5%, P = .429). There was no significant difference in 10-year survival between SV and BV groups (78% vs. 88%, P = .467).

CONCLUSIONS

Complex ACHD cardiac transplant recipients have a high incidence of early morbidities after transplantation. However, long-term outcomes were acceptable.

Increased frequency of heart transplantation, shortened waitlist time and preserved post-transplant survival in adults with congenital heart disease, on the new heart transplant allocation system

Historically, adult congenital patients have longer waitlist time and worse outcomes on the heart transplant waitlist as well as poorer early post-transplant survival. A new heart transplantation allocation system was implemented in the United States on October 18, 2018. The effect of the new allocation system on adult congenital patients is unknown. Adult congenital patients listed for transplantation between November 1, 2015 and September 30, 2019 registered in the United Network for Organ Sharing were included in the study. October 18, 2018 was used as the limit to distribute listed and transplanted patients into old and new groups. A total of 399 patients were listed for heart transplant only, 284 in the old system and 115 in the new system. Clinical characteristics were similar between both groups. The cumulative incidence of poor outcome on the transplant list was similar in both groups (P = .23), but the cumulative incidence of transplant was higher in the new system group (P < .009) and was associated with a shorter waitlist time. The one-year post-transplant outcome was similar between old and new groups (P = .37). The new allocation system has benefited adult congenital patients with increased cumulative frequency of transplantation without worsening short-term survival after transplantation.

Canadian Cardiovascular Society/Canadian Cardiac Transplant Network Position Statement on Heart Transplantation: Patient Eligibility, Selection, and Post-Transplantation Care

Significant practice-changing developments have occurred in the care of heart transplantation candidates and recipients over the past decade. This Canadian Cardiovascular Society/Canadian Cardiac Transplant Network Position Statement provides evidence-based, expert panel recommendations with values and preferences, and practical tips on: (1) patient selection criteria; (2) selected patient populations; and (3) post transplantation surveillance. The recommendations were developed through systematic review of the literature and using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. The evolving areas of importance addressed include transplant recipient age, frailty assessment, pulmonary hypertension evaluation, cannabis use, combined heart and other solid organ transplantation, adult congenital heart disease, cardiac amyloidosis, high sensitization, and post-transplantation management of antibodies to human leukocyte antigen, rejection, cardiac allograft vasculopathy, and long-term noncardiac care. Attention is also given to Canadian-specific management strategies including the prioritization of highly sensitized transplant candidates (status 4S) and heart organ allocation algorithms. The focus topics in this position statement highlight the increased complexity of patients who undergo evaluation for heart transplantation as well as improved patient selection, and advances in post-transplantation management and surveillance that have led to better long-term outcomes for heart transplant recipients.

Heart transplantation at a single tertiary adult congenital heart disease centre: Too little, too late?

BACKGROUND

Heart failure (HF) is the leading cause of death in adults with congenital heart disease (ACHD). Heart transplantation can be an effective therapy for them, albeit unfavourable anatomy, end-organ damage, pulmonary vascular disease, HLA sensitization and lack of robust selection criteria currently limit its application.

METHODS

Consecutive CHD patients considered for heart or combined heart and lung transplantation at our tertiary ACHD centre between 2000 and 2018 constitute our study population. Baseline characteristics and outcome, including transplantation and death, were obtained for all patients from designated databases, medical records and the UK Office for National Statistics.

RESULTS

From a total of more than 9000 active ACHD patients under follow-up, 166 (median age 40.4 years) fulfilled inclusion criteria, with a broad spectrum of underlying diagnosis: univentricular heart 22.3%, systemic right ventricle 22.3%, systemic-to-pulmonary shunts and Eisenmenger syndrome 16.3%, left sided valvular lesions 14.5%, tetralogy of Fallot 12.7%, CHD associated with cardiomyopathy 4.8% and other 7.2%. There was a high overall mortality with 39.2% of patients dying over a median follow-up of 2.7 years. A minority of patients (22.9%) were eventually listed and only 13.3% from the 166 patients were actually transplanted. Survival at 1 year after transplantation was 81.8% and remained high long-term (65.5% at 15 years). We describe herewith in detail characteristics and outcome of our cohort and present the transplantation pathway followed.

CONCLUSION

Of the small number of patients with ACHD considered for heart transplantation at a large tertiary centre, there was high overall mortality, with only a fraction of patients being actually transplanted. Patients who received transplantation, however, had a good outcome. Better patient selection and timing are clearly warranted so that more ACHD patients are considered and potentially benefit from this effective form of therapy.

Post-transplant survival in adult congenital heart disease patients as compared to dilated and ischemic cardiomyopathy patients; an analysis of the thoracic ISHLT registry

Previous studies have shown that adult congenital heart disease (ACHD) is associated with high early post-transplant mortality but improved long-term survival in comparison to the overall heart transplant population. We aimed to evaluate survival outcomes of ACHD in adult transplant recipient patients as specifically compared to ischemic (ICM) and dilated cardiomyopathy (DCM) groups. Adult heart transplant recipients between 2004 and 2014 were identified from the ISHLT registry. We used Kaplan-Meier analysis to evaluate overall survival, 1-year survival, and 1-year conditional survival among etiology groups and multivariable Cox proportional hazard (PH) models to assess the association between etiology of cardiomyopathy and 1-year and long-term all-cause mortality and cause-specific mortality. We included 30 130 heart transplant recipients. One-year survival was 78.3% in ACHD, 84.3% in ICM, and 86.2% in DCM patients (P < .001). By multivariable analysis, during first post-transplant year, ACHD and ICM patients were at significantly higher mortality risk than DCM. Adjusted post-transplant mortality risk, conditional on 1-year survival, was not statistically different in ACHD and DCM while ICM patients had 17% higher long-term mortality risk than DCM patients leading to overall worse outcomes in ICM patients. Therefore, ICM patients have poorer outcomes in comparison to both DCM and ACHD patients.

Adult Congenital Heart Disease: Current Early Expectations After Cardiac Transplantation

BACKGROUND

Early mortality has plagued the otherwise good outcomes of heart transplantation in patients with adult congenital heart disease (ACHD), but perioperative care is improving. This study sought to identify risk factors for 1-year mortality currently and examine the results of patients without those risk factors compared with patients who did not have ACHD (nACHD).

METHODS

The United Network of Organ Sharing database was searched for all adult (>17 years of age) heart transplant recipients from 2000 to 2018. They were divided into an early era and a late era. A multivariate analysis identified risk factors for 1-year mortality in the late era. Patients without these risk factors were compared with the nACHD group by Kaplan-Meier analysis.

RESULTS

A total of 495 patients with ACHD were identified from 2000 to 2008, and 666 were identified from 2009 to 2018. The recent era had better 1-year survival (P <.001) and overall survival (P = .003) than did the era from 2000 to 2008. Patients with ACHD were different from the nACHD population in age (37 years vs 57 years), body mass index greater than 25 kg/m² (45% vs 66%), incidence of renal dysfunction (23% vs 28%) and liver dysfunction (29% vs 23%), sensitization (38% vs 29%), and ischemic times (3.5 hours vs 3.1 hours). Multivariate analysis identified body mass index greater than 25 kg/m² (hazard ratio [HR], 1.79), renal dysfunction (HR, 1.85), liver dysfunction (HR, 1.69), and longer ischemic time (HR, 1.46) as risk factors for early mortality. Patients with only 1 of the first 3 categorical risk factors had 1-year survival comparable to that reported in patients with nACHD.

CONCLUSIONS

Patients with ACHD had better early and long-term outcomes in the recent era. When only 1 of 3 pretransplant risk factors for early mortality was present, patients had survival equal to that of nACHD patients and perhaps better long-term survival.

Cardiopulmonary Exercise Testing-A Valuable Tool, Not Gatekeeper When Referring Patients With Adult Congenital Heart Disease for Transplant Evaluation

INTRODUCTION

Treatment of patients with adult congenital heart disease (ACHD) with advanced therapies including heart transplant (HT) is often delayed due to paucity of objective prognostic markers for the severity of heart failure (HF). While the utility of Cardiopulmonary Exercise Testing (CPET) in non-ACHD patients has been well-defined as it relates to prognosis, CPET for this purpose in ACHD is still under investigation.

METHODS

We performed a retrospective cohort study of 20 consecutive patients with ACHD who underwent HT between March 2010 and February 2016. Only 12 of 20 patients underwent CPET prior to transplantation. Demographics, standard measures of CPET interpretation, and 30-day and 1-year post transplantation outcomes were collected.

RESULTS

Patient Characteristics. Twenty patients with ACHD were transplanted at a median of 40 years of age (range: 23-57 years). Of the 12 patients who underwent CPET, 4 had undergone Fontan procedures, 4 had tetralogy of Fallot, 3 had d-transposition of the great arteries, and 1 had Ebstein anomaly. Thirty-day and one-year survival was 100%. All tests included in the analysis had a peak respiratory quotient _1.0. The median peak oxygen consumption per unit time (_VO2) for all diagnoses was 18.2 mL/kg/min (46% predicted), ranging from 12.2 to 22.6.

CONCLUSION

There is a paucity of data to support best practices for patients with ACHD requiring transplantation. While it cannot be proven based on available data, it could be inferred that outcomes would have been worse or perhaps life sustaining options unavailable if providers delayed referral because of the lack of attainment of CPET-specific thresholds.

Noteworthy Literature Published in 2016 for Thoracic Organ Transplantation Anesthesiologists

This article is first in the series to review the published literature on perioperative issues in patients undergoing thoracic solid organ transplantations. We present recent literature from 2016 on preoperative considerations, organ preservation, intraoperative anesthesia management, surgical techniques, postoperative complications, and the impact of perioperative management on short- and long-term outcomes that are pertinent to thoracic transplantation anesthesiologists.