Impact of Durable Ventricular Assist Device Support on Outcomes of Patients with Congenital Heart Disease Waiting for Heart Transplant

Mechanical circulatory support devices in adults with congenital heart disease

PURPOSE OF REVIEW

Mechanical circulatory support is used frequently as a method of stabilizing patients with end stage heart failure who are unable to safely await allograft availability. While this technology has been fundamentally important in supporting patients with normal cardiac anatomy, it is still used infrequently in adult patients with congenital heart disease and end-stage heart failure. Here, we review the data on mechanical circulatory support technology in this small but growing population of patients with chronic heart disease prone to the development of circulatory failure.

RECENT FINDINGS

Mechanical circulatory support (MCS) has been increasingly employed in adults with congenital heart disease (ACHD) as a bridge to transplant. The new United Network for Organ Sharing listing system favoring temporary MCS use with a higher listing status offers another tool to stabilize ACHD patients and potentially shorten wait times. Both temporary and Durable MCS could help improve transplant candidacy and posttransplant outcomes in select groups of ACHD patients.

SUMMARY

Durable and temporary MCS have the potential to significantly improve access to transplant and overall transplant outcomes in ACHD patients.

An Analysis of 186 Transplants for Pediatric or Congenital Heart Disease: Impact of Pretransplant VAD

BACKGROUND

We reviewed our management strategy and outcome data for all 181 patients with pediatric or congenital heart disease who received 186 heart transplants from January 1, 2011, to March 1, 2022, and evaluated the impact of pretransplant ventricular assist device (VAD).

METHODS

Continuous variables are presented as mean (SD); median [interquartile range] (range). Categorical variables are presented as number (percentage). Univariable associations with long-term mortality were assessed with Cox proportional hazards models. Impact of pretransplant VAD on survival was estimated with multivariable models.

RESULTS

Pretransplant VAD was present in 53 of 186 transplants (28.5%). Patients with VAD were younger (years): 4.8 (5.6); 1 [0.5-8] (0.1-18) vs 12.1 (12.7); 10 [0.7-17] (0.1-58); P = .0001. Patients with VAD had a higher number of prior cardiac operations: 3.0 (2.3); 2 [1-4] (1-12) vs 1.8 (1.9); 2 [0-3] (0-8); P = .0003. Patients with VAD were also more likely to receive an ABO-incompatible transplant: 10 of 53 (18.9%) vs 9 of 133 (6.8%); P = .028. Univariable associations with long-term mortality included: In multivariable analysis, pretransplant VAD did not impact survival while controlling for each one of the factors shown in univariable analysis to be associated with long-term mortality. Kaplan-Meier 5-year survival (95% CI) was 85.8% (80.0%-92.1%) for all patients, 84.3% (77.2%-92.0%) without pretransplant VAD, and 91.1% (83.1%-99.9%) with pretransplant VAD.

CONCLUSIONS

Our single-institution analysis of 181 patients receiving 186 heart transplants for pediatric or congenital heart disease over 11.25 years reveals similar survival in patients with (n = 51) and without (n = 130) pretransplant VAD. The presence of a pretransplant VAD is not a risk factor for mortality after transplantation for pediatric or congenital heart disease.

A single-institutional experience with 36 children less than 5 kilograms supported with the Berlin Heart: Comparison of congenital versus acquired heart disease

OBJECTIVES

We reviewed outcomes in all 36 consecutive children <5 kg supported with the Berlin Heart pulsatile ventricular assist device at the University of Florida, comparing those with acquired heart disease (n = 8) to those with congenital heart disease (CHD) (n = 28).

METHODS

The primary outcome was mortality. The Kaplan-Meier method and log-rank tests were used to assess group differences in long-term survival after ventricular assist device insertion. T-tests using estimated survival proportions were used to compare groups at specific time points.

RESULTS

Of 82 patients supported with the Berlin Heart at our institution, 49 (49/82 = 59.76%) weighed <10 kg and 36 (36/82 = 43.90%) weighed <5 kg. Of 36 patients <5 kg, 26 (26/36 = 72.22%) were successfully bridged to transplantation. (The duration of support with ventricular assist device for these 36 patients <5 kg was [days]: median = 109, range = 4-305.) Eight out of 36 patients <5 kg had acquired heart disease, and all eight [8/8 = 100%] were successfully bridged to transplantation. (The duration of support with ventricular assist device for these 8 patients <5 kg with acquired heart disease was [days]: median = 50, range = 9-130.) Twenty-eight of 36 patients <5 kg had congenital heart disease. Eighteen of these 28 [64.3%] were successfully bridged to transplantation. (The duration of support with ventricular assist device for these 28 patients <5 kg with congenital heart disease was [days]: median = 136, range = 4-305.) For all 36 patients who weighed <5 kg: 1-year survival estimate after ventricular assist device insertion = 62.7% (95% confidence interval = 48.5-81.2%) and 5-year survival estimate after ventricular assist device insertion = 58.5% (95% confidence interval = 43.8-78.3%). One-year survival after ventricular assist device insertion = 87.5% (95% confidence interval = 67.3-99.9%) in acquired heart disease and 55.6% (95% confidence interval = 39.5-78.2%) in CHD, P = 0.036. Five-year survival after ventricular assist device insertion = 87.5% (95% confidence interval = 67.3-99.9%) in acquired heart disease and 48.6% (95% confidence interval = 31.6-74.8%) in CHD, P = 0.014.

CONCLUSION

Pulsatile ventricular assist device facilitates bridge to transplantation in neonates and infants weighing <5 kg; however, survival after ventricular assist device insertion in these small patients is less in those with CHD in comparison to those with acquired heart disease.

Heart transplantation surgery in children and young adults with congenital heart disease

BACKGROUND

Pediatric cardiac transplantation remains a surgical challenge as a variety of cardiac and vessel malformation are present in patients with congenital heart disease (CHD). Despite limited availability and acceptability of donor hearts, the number of heart transplantations remains on a stable level with improved survival and quality of life.

OBSERVATION

As treatment options for CHD continue to improve and the chances of survival increase, more adult CHD patients are listed for transplantation. This review focuses on the clinical challenges and modified techniques of pediatric heart transplantations.

CONCLUSION

Not only knowledge of the exact anatomy, but above all careful planning, interdisciplinary cooperation and surgical experience are prerequisites for surgical success.

Heart Transplantation in Patients Less Than 18 Years of Age: Comparison of 2 Eras Over 36 Years and 323 Transplants at a Single Institution

BACKGROUND

We reviewed our management strategy and outcome data for all 311 patients less than 18 years of age who underwent 323 heart transplants at our institution (1986 to 2022) in order to assess changes in patterns of practice and outcomes over time and to compare two consecutive eras: era 1 (154 heart transplants [1986 to 2010]) and era 2 (169 heart transplants [2011 to 2022]).

STUDY DESIGN

Descriptive comparisons between the two eras were performed at the level of the heart transplant for all 323 transplants. Kaplan-Meier survival analyses were performed at the level of the patient for all 311 patients, and log-rank tests were used to compare groups.

RESULTS

Transplants in era 2 were younger (6.6 ± 6.5 years vs 8.7 ± 6.1 years, p = 0.003). More transplants in era 2 were in infants (37.9% vs 17.5%, p < 0.0001), had congenital heart disease (53.8% vs 39.0%, p < 0.010), had high panel reactive antibody (32.1% vs 11.9%, p < 0.0001), were ABO-incompatible (11.2% vs 0.6%, p < 0.0001), had prior sternotomy (69.2% vs 39.0%, p < 0.0001), had prior Norwood (17.8% vs 0%, p < 0.0001), had prior Fontan (13.6% vs 0%, p < 0.0001), and were in patients supported with a ventricular assist device at the time of heart transplant (33.7% vs 9.1%, p < 0.0001). Survival at 1, 3, 5, and 10 years after transplant was as follows: era 1 = 82.4% (76.5 to 88.8), 76.9% (70.4 to 84.0), 70.7% (63.7 to 78.5), and 58.8% (51.3 to 67.4), respectively; era 2 = 90.3% (85.7 to 95.1), 85.4% (79.7 to 91.5), 83.0% (76.7 to 89.8), and 66.0% (49.0 to 88.8), respectively. Overall Kaplan-Meier survival in era 2 was better (log-rank p = 0.03).

CONCLUSIONS

Patients undergoing cardiac transplantation in the most recent era are higher risk but have better survival.

Incidence and Outcomes of Advanced Heart Failure in Adults With Congenital Heart Disease

BACKGROUND

There are limited data about the stage D heart failure (advanced HF) in adults with congenital heart disease. Our study objectives were (1) to determine the incidence of new-onset advanced HF in patients and the relationship between advanced HF and all-cause mortality and (2) to determine the relationship between therapies for advanced HF and all-cause mortality.

METHODS

Retrospective cohort study of adults with congenital heart disease at Mayo Clinic (2003-2019). We defined advanced HF using the European Society of Cardiology diagnostic criteria for advanced HF. Therapies received by the patients with advanced HF were classified into 3 mutually exclusive groups (treatment pathways): (1) conventional cardiac intervention, (2) transplant listing, and (3) palliative care.

RESULTS

Of 5309 patients without advanced HF at baseline assessment, 432 (8%) developed advanced HF during follow-up (1.1%/y), and the incidence of advanced HF was higher in patients with severe or complex congenital heart disease. Onset of advanced HF was associated with 6-fold increase in the risk of mortality. Conventional cardiac intervention was associated with significantly higher risk of mortality as compared to transplant listing. The longer the interval from the initial onset of advanced HF to transplant evaluation, the lower the odds of being listed for transplant.

CONCLUSIONS

Based on these data, we postulate that early identification of patients with advanced HF, and a timely referral for transplant evaluation (instead of conventional cardiac intervention) may offer the best chance of survival for these critically ill patients. Further studies are required to validate this postulation.

Treatment of advanced heart failure in adults with congenital heart disease: a narrative review and clinical cases

BACKGROUND AND OBJECTIVE

The number of adults with congenital heart disease (ACHD) is increasing worldwide. Almost all congenital cardiac lesions can be successfully treated due to the progress in neonatal surgery and pediatric cardiology with a high likelihood of surviving until adulthood. However, ACHD frequently develop sequelae related to the initial cardiac anomaly. Heart failure (HF) is one of the most common complications associated with a high morbidity and mortality.

METHODS

The authors did search the PubMed database regarding relevant content covering publications up to March 2022. Relevant manuscripts were classified according to the impact factor of the journal, being a guideline manuscript, a position paper by a society or a comprehensive review of the current literature.

KEY CONTENT AND FINDINGS

Optimal HF treatment remains an unmet need in ACHD. In particular, advanced HF therapy with cardiac resynchronization therapy, ventricular assist devices or organ transplantation is still very different and more specific in ACHD compared to non-ACHD. This review aims to compile international views and evidence from the literatures on the treatment of advanced HF in ACHD. Current challenges, but also the success of different treatment strategies in ACHD are illustrated by clinical cases.

CONCLUSIONS

The main finding of the review is that data is still scarce regarding ACHD with advanced HF and international efforts to collect data regarding these patients needed to improve the current standard of care.

Study design and rationale of the pAtients pResenTing with cOngenital heaRt dIseAse Register (ARTORIA-R)

Aim

Due to improved therapy in childhood, many patients with congenital heart disease reach adulthood and are termed adults with congenital heart disease (ACHD). ACHD often develop heart failure (HF) as a consequence of initial palliative surgery or complex anatomy and subsequently require advanced HF therapy. ACHD are usually excluded from trials evaluating heart failure therapies, and in this context, more data about heart failure trajectories in ACHD are needed to guide the management of ACHD suffering from HF.

Methods and results

The pAtients pResenTing with cOngenital heaRt dIseAse Register (ARTORIA‐R) will collect data from ACHD evaluated or listed for heart or heart‐combined organ transplantation from 16 countries in Europe and the Asia/Pacific region. We plan retrospective collection of data from 1989–2020 and will include patients prospectively. Additional organizations and hospitals in charge of transplantation of ACHD will be asked in the future to contribute data to the register. The primary outcome is the combined endpoint of delisting due to clinical worsening or death on the waiting list. The secondary outcome is delisting due to clinical improvement while on the waiting list. All‐cause mortality following transplantation will also be assessed. The data will be entered into an electronic database with access to the investigators participating in the register. All variables of the register reflect key components important for listing of the patients or assessing current HF treatment.

Conclusion

The ARTORIA‐R will provide robust information on current management and outcomes of adults with congenital heart disease suffering from advanced heart failure.

Heart failure in adult congenital heart disease: tetralogy of Fallot

The number of rTOF patients who survive into adulthood is steadily rising, with currently more than 90% reaching the third decade of life. However, rTOF patients are not cured, but rather have a lifelong increased risk for cardiac and non-cardiac complications. Heart failure is recognized as a significant complication. Its occurrence is strongly associated with adverse outcome. Unfortunately, conventional concepts of heart failure may not be directly applicable in this patient group. This article presents a review of the current knowledge on HF in rTOF patients, including incidence and prevalence, the most common mechanisms of heart failure, i.e., valvular pathologies, shunt lesions, left atrial hypertension, primary left heart and right heart failure, arrhythmias, and coronary artery disease. In addition, we will review information regarding extracardiac complications, risk factors for the development of heart failure, clinical impact and prognosis, and assessment possibilities, particularly of the right ventricle, as well as management strategies. We explore potential future concepts that may stimulate further research into this field.

Transplant and mechanical circulatory support in patients with adult congenital heart disease

Advances in surgery and pediatric care over the past decades have achieved improved survival for children born with congenital heart disease (CHD) and have produced a large, growing population of patients with adult congenital heart disease (ACHD). Heart failure has emerged as the leading cause of death and a major cause of morbidity among the ACHD population, while as little evidence supports the efficacy of guideline-directed medical therapies in this population. It is increasingly important that clinicians caring for these patients understand how to utilize mechanical circulatory support (MCS) in ACHD. In this review, we summarize the data on transplantation and MCS in the ACHD-heart failure population and provide a framework for how ACHD patients may benefit from advanced heart failure therapies like transplantation and MCS.

HeartMate 3 in a ccTGA patient

A 49-year-old female with congenitally corrected (or levo-) transposition of the great arteries complicated by nonischemic cardiomyopathy presented for worsening heart failure despite guideline-directed medical therapy and was found to be in cardiogenic shock. She successfully underwent ventricular assist device placement with a HeartMate III to her systemic right ventricle as a bridge to transplantation.

Surgical outcomes in complex adult congenital heart disease: a brief review

Life expectancy of patients with congenital heart disease (CHD) continues to increase dramatically over the last few decades, primarily due to significant medical and surgical advancements in the field. Adult congenital heart disease (ACHD) patients are now living longer but continue to face morbidity and reduced long-term survival when compared to the general population. We briefly describe the growth of ACHD with a focus on surgical procedures and outcomes in the more complex lesions including Tetralogy of Fallot, Ebsteins Anomaly of the tricuspid valve, Coarctation of the Aorta, Transposition of the Great Arteries and single ventricle lesions. The advancing role of mechanical circulatory support and cardiac transplantation in ACHD patients is also highlighted. Cardiac surgery in these patients continues to improve with low surgical mortality rate and outstanding long-term outcomes and efficacy.

Expanding the donor pool for congenital heart disease transplant candidates by implementing 3D imaging-derived total cardiac volumes

BACKGROUND

Heart transplant waitlist mortality remains high in infants <1 year of age and among those with CHD. Currently, the median accepted donor-to-recipient weight percentage is approximately 130% of the recipient's weight. We hypothesized that patients with CHD may accept a larger organ using novel 3D-derived imaging data to estimate donor and recipient TCV.

METHODS

A single-center, retrospective study was performed using CT data for 13 patients with CHD and 94 control patients. 3D visualization software was used to create digital 3D heart models that provide an estimate of TCV. In addition, echocardiograms obtained prior to cross-sectional imaging were reviewed for presence of ventricular chamber dilation.

RESULTS

Sixty-two percent (8/13) of patients with CHD had 3D-derived TCV resulting in a weight that was >130% larger than their actual weight. This was seen in single-ventricle patients following Blalock-Taussig shunt and Fontan palliation, and patients with biventricular repair. Of those, 75% (6/8) had reported moderate-to-severe ventricular chamber dilation by echocardiogram or cardiac magnetic resonance imaging.

CONCLUSIONS

In a large portion of patients with CHD, 3D-derived TCV place the recipient at a higher listing weight than their actual weight. We propose obtaining cross-sectional imaging to better assess TCV in a recipient, which may increase the donor range for CHD recipients and improve organ utilization in pediatrics.