Mortality and morbidity after combined heart and liver transplantation in the failing Fontan: An updated dual center retrospective study

INTRODUCTION

As the adult Fontan population with Fontan associated liver disease continues to increase, more patients are being referred for transplantation, including combined heart and liver transplantation.

METHODS

We report updated mortality and morbidity outcomes after combined heart and liver transplant in a retrospective cohort series of 40 patients (age 14 to 49 years) with Fontan circulation across two centers from 2006-2022.

RESULTS

The 30-day, 1-year, 5-year and 10-year survival rate was 90%, 80%, 73% and 73% respectively. Sixty percent of patients met a composite comorbidity of needing either post-transplant mechanical circulatory support, renal replacement therapy or tracheostomy. Cardiopulmonary bypass time > 283 min (4.7 h) and meeting the composite comorbidity were associated with mortality by Kaplan Meier analysis.

CONCLUSION

Further study to mitigate early mortality and the above comorbidities as well as the high risk of bleeding and vasoplegia in this patient population is warranted.

Symptomatic Myocardial Bridging in D-Transposition of the Great Arteries Post-Arterial Switch

We present Stanford's experience with patients post-arterial switch operation presenting with chest pain found to have hemodynamically significant myocardial bridging. The evaluation of symptomatic patients post-arterial switch should not only include assessment for coronary ostial patency but also for nonobstructive coronary conditions such as myocardial bridging. (Level of Difficulty: Advanced.).

Durable Mechanical Circulatory Support in Adult Congenital Heart Disease: Reviewing Clinical Considerations and Experience

Adults with congenital heart disease (ACHD) patients are one of the fastest growing populations in cardiology, and heart failure (HF) is the most common cause of morbidity and mortality amongst them. The need for advanced HF therapies in ACHD patients stands to grow substantially. The anatomic considerations for placing durable mechanical circulatory support (MCS) devices in ACHD patients often require specialized approaches. Despite this, increasing evidence suggests that durable MCS can be implanted safely with favorable outcomes in ACHD patients. Expansion of MCS use in ACHD patients is imperative to improve their clinical outcomes. Knowledge of ACHD-specific anatomic and physiologic considerations is crucial to HF programs’ success as they work to provide care to this growing population.

Tetralogy of Fallot and Aortic Dissection: Implications in Management

We present the case of a 61-year-old man with tetralogy of Fallot postrepair and mechanical aortic valve replacement with an aortic root/ascending/arch aneurysm with chronic type A aortic dissection. He underwent uncomplicated aortic root and total arch replacement. Continued surveillance for aortic aneurysm is necessary in the tetralogy of Fallot population. (Level of Difficulty: Intermediate.).

Deficits in the Functional Muscle-Bone Unit in Youths with Fontan Physiology

OBJECTIVE

To determine whether dual energy X-ray absorptiometry (DXA), a clinically available tool, mirrors the magnitude of deficits in trabecular and cortical bone mineral density (BMD) demonstrated on peripheral quantitative computed tomography in youth with Fontan physiology.

STUDY DESIGN

We aimed to describe DXA-derived BMD at multiple sites and to investigate the relationship between BMD and leg lean mass, a surrogate for skeletal muscle loading. Subjects with Fontan (n = 46; aged 5-20 years) underwent DXA in a cross-sectional study of growth and bone and muscle health as described previously. Data from the Bone Mineral Density in Childhood Study were used to calculate age-, sex-, and race-specific BMD z-scores of the whole body, lumbar spine, hip, femoral neck, distal one-third radius, ultradistal radius, and leg lean mass z-score (LLMZ).

RESULTS

Fontan BMD z-scores were significantly lower than reference at all sites-whole body, -0.34 ± 0.85 (P = .01); spine, -0.41 ± 0.96 (P = .008); hip, -0.75 ± 1.1 (P < .001); femoral neck, -0.73 ± 1.0 (P < .001); distal one-third radius, -0.87 ± 1.1 (P < .001); and ultradistal radius. -0.92 ± 1.03 (P < .001)-as was LLMZ (-0.93 ± 1.1; P < .001). Lower LLMZ was associated with lower BMD of the whole body (R² = 0.40; P < .001), lumbar spine (R² = 0.16; P = .005), total hip (R² = 0.32; P < .001), femoral neck (R² = 0.47; P < .001), and ultradistal radius (R² = 0.35; P < .001).

CONCLUSIONS

Patients with Fontan have marked deficits in both cortical (hip, distal one-third radius) and trabecular (lumbar spine, femoral neck, ultradistal radius) BMD. Lower LLMZ is associated with lower BMD and may reflect inadequate skeletal muscle loading. Interventions to increase muscle mass may improve bone accrual.

Heart failure with reduced and preserved ejection fraction in adult congenital heart disease

Heart failure with reduced ejection fraction (HFrEF) is common in patients with adult congenital heart disease. Many of the most common congenital defects have a high prevalence of HFrEF, including left-sided obstructive lesions (aortic stenosis, coarctation of the aorta, Shone complex), tetralogy of Fallot, Ebstein anomaly, lesions in which there is a systemic right ventricle, and lesions palliated with a Fontan circulation. However, heart failure with preserved ejection fraction (HFpEF) is also prevalent in all these lesions. Comprehensive evaluation includes physical exam, biomarkers, echocardiography and advanced imaging, exercise stress testing, and, in some cases, invasive hemodynamics. Guideline-directed medical therapy for HFrEF can be applied to left-sided lesions and may be considered on an individual basis for systemic right ventricle and single-ventricle patients. Medical therapy is limited for HFpEF. However, in both HFrEF and HFpEF, ventricular dyssynchrony and arrhythmias play an important role, and medications for rhythm control, ablation, and cardiac resynchronization therapy should be considered. Finally, aggressive management of cardiovascular risk factors and comorbidities, including, but not limited to, hypertension, obesity, diabetes, dyslipidemia, and obstructive sleep apnea, cannot be overemphasized.

A 40-Year-Old Man With Tricuspid Atresia, Status Post-Fontan, With Severe COVID-19 Pneumonia and Pneumothorax

We report a case of COVID-19 in an adult single-ventricle patient post-Fontan—to our knowledge, the first report in this population documenting the use of the latest management recommendations for this novel disease. Additionally, this patient had significant pre-existing ventricular dysfunction, valvular disease, and comorbidities including HIV. (Level of Difficulty: Advanced.)

Does liver biopsy accurately measure fibrosis in Fontan-associated liver disease? A comparison of liver biopsy pre-combined heart and liver transplant and liver explant post-transplant

The accuracy of liver biopsy to stage fibrosis due to Fontan-associated liver disease (FALD) remains unclear. We compared the results of biopsy pre-combined heart and liver transplantation (CHLT) to the results of whole liver explant. Liver biopsy and explants from 15 Fontan patients (ages 16-49, median 28 years) were retrospectively reviewed. Staging was as follows: stage 0: no fibrosis, stage 1: pericellular fibrosis, stage 2: bridging fibrosis, and stage 3: regenerative nodules. There is no stage 4. Clinical characteristics including Model of End-stage Liver Disease eXcluding INR and Varices, Ascites, Splenomegaly, and Thrombocytopenia (VAST) scores were collected, and descriptive statistics and Mann-Whitney U tests were used to analyze the data. All patients had biopsies with at least bridging fibrosis, and all had nodularity on explant; transjugular biopsy never overestimated fibrosis. Explant showed higher-grade fibrosis (stage 3) than pre-CHLT biopsy (stage 2) in 6 of 15 patients and equal grade of fibrosis (stage 3) in 9 of 15 patients. Though clinical characteristics varied significantly, VAST score was ≥2 in all but two patients. Transjugular liver biopsy does not overestimate and can underestimate fibrosis in Fontan patients undergoing CHLT, likely due to the patchy nature of fibrosis in FALD.

Short-term outcomes of en bloc combined heart and liver transplantation in the failing Fontan

Patients with failing Fontan physiology and liver cirrhosis are being considered for combined heart and liver transplantation. We performed a retrospective review of our experience with en bloc combined heart and liver transplantation in Fontan patients > 10 years old from 2006 to 18 per Institutional Review Board approval. Six females and 3 males (median age 20.7, range 14.2-41.3 years) underwent en bloc combined heart and liver transplantation. Indications for heart transplant included ventricular dysfunction, atrioventricular valve regurgitation, arrhythmia, and/or lymphatic abnormalities. Indication for liver transplant included portal hypertension and cirrhosis. Median Fontan/single ventricular end-diastolic pressure was 18/12 mm Hg, respectively. Median Model for End-Stage Liver Disease excluding International Normalized Ratio score was 10 (7-26), eight patients had a varices, ascites, splenomegaly, thrombocytopenia score of ≥ 2, and all patients had cirrhosis. Median cardiopulmonary bypass and donor ischemic times were 262 (178-307) and 287 (227-396) minutes, respectively. Median intensive care and hospital stay were 19 (5-96) and 29 (13-197) days, respectively. Survival was 100%, and rejection was 0% at 30 days and 1 year post-transplant. En bloc combined heart and liver transplantation is an acceptable treatment in the failing Fontan patient with liver cirrhosis.

Repair of Untreated Older Patients With Tetralogy of Fallot With Major Aortopulmonary Collaterals

BACKGROUND

Our programmatic approach to tetralogy of Fallot with major aortopulmonary collaterals emphasizes single-stage unifocalization with complete intracardiac repair during infancy. Little is known about suitability for complete repair in patients beyond infancy. We sought to analyze outcomes of our approach in older patients with previously untreated tetralogy of Fallot with major aortopulmonary collaterals.

METHODS

Any patient with this lesion not treated before 2 years of age referred to our center from 2002 to 2017 met inclusion criteria.

RESULTS

Of 33 patients, 32 were out-of-state (64% international) referrals, and 33% (n = 11) were older than 9 years, had polycythemia, or at least 1 high pressure collateral (>25 mm Hg). Complete repair was achieved in 94% (n = 31) of patients, 82% (n = 27) in one stage and 12% (n = 4) after unifocalization to a central shunt. The median right ventricular-to-aortic pressure ratio was 0.31 after the operation and 0.37 at follow-up. At a median of 4.8 years after repair, 9 patients (19%) underwent reintervention, including 5 conduit and 7 branch pulmonary artery interventions. Three patients also underwent aortic valve replacement.

CONCLUSIONS

In this selected cohort of older patients with previously unoperated tetralogy of Fallot with major aortopulmonary collaterals, outcomes were comparable with infants undergoing treatment according to our approach. These findings support the notion that patients who are either born in low-resource settings or present to health care providers beyond infancy should be considered candidates and evaluated for complete repair.

Short-term outcomes following implementation of a dedicated young adult congenital heart disease transition program

OBJECTIVE

Transition from pediatric to adult care is a critical time for patients with congenital heart disease. Lapses in care can lead to poor outcomes, including increased mortality. Formal transition clinics have been implemented to improve success of transferring care from pediatric to adult providers; however, data regarding outcomes remain limited. We sought to evaluate outcomes of transfer within a dedicated transition clinic for young adult patients with congenital heart disease.

DESIGN, SETTING, AND PATIENTS

We performed a retrospective analysis of all 73 patients seen in a dedicated young adult congenital heart disease transition clinic from January 2012 to December 2015 within a single academic institution that delivered pediatric and adult care at separate children's and adult hospitals, respectively.

INTERVENTION AND OUTCOME MEASURES

Demographic characteristics including congenital heart disease severity, gender, age, presence of comorbidities, presence of cardiac implantable electronic devices, and type of insurance were correlated to success of transfer. Rate of successful transfer was evaluated, and multivariate analysis was performed to determine which demographic variables were favorably associated with transfer.

RESULTS

Thirty-nine percent of patients successfully transferred from pediatric to adult services during the study period. Severe congenital heart disease (OR 4.44, 95% CI 1.25-15.79, P = .02) and presence of a cardiac implantable electronic device (OR 4.93, 95% CI 1.18-20.58, P = .03) correlated with transfer. Trends favoring successful transfer with presence of comorbidities and private insurance were also noted.

CONCLUSIONS

Despite a dedicated transition clinic, successful transfer rates remained relatively low though comparable to previously published rates. Severity of disease and presence of implantable devices correlated with successful transfer. Other obstacles to transfer remain and require combined efforts from pediatric and adult care systems, insurance carriers, and policy makers to improve transfer outcomes.

Academic achievement and primary care specialty selection of volunteers at a student-run free clinic

BACKGROUND

Previous studies have reached conflicting conclusions about the associations between service and academic achievement and service and primary care specialty choice.

PURPOSES

This study examines the associations between service at a student-run clinic and academic achievement and primary care specialty choice.

METHODS

Retrospective review of medical student service and statistical analysis of grade point average (GPA), Step 1 and Step 2 Clinical Knowledge (CK) scores, and specialty choice were conducted, as approved by our Institutional Review Board.

RESULTS

Volunteers, compared to nonvolunteers, had higher GPA (3.59 ± 0.33 vs. 3.40 ± 0.39, p < .001), Step 1 (229 ± 19 vs. 220 ± 21, p < .001), and Step 2 CK (240 ± 18 vs. 230 ± 21, p < .001) scores, but did not pursue primary care specialties at a significantly higher percentage (52% vs. 51%, χ² = .051, p = .82).

CONCLUSIONS

Further exploration of the associations between service and academic achievement and primary care specialty choice is warranted.

Abstract 305: Nebivolol Confers Mitochondria-Targeted Cardioprotection in Isoproterenol-Induced Acute Stressor State

Introduction: Isoproterenol-induced acute stressor state simulates injury from burns or trauma, and results in Ca 2+ overloading and oxidative stress in diverse tissues, including cardiac myocytes and their subsarcolemmal mitochondria (SSM), overwhelming endogenous Zn 2+ -based antioxidant defenses. We hypothesized that pretreatment with nebivolol (Nebi), having dual beta-1 antagonistic and novel beta-3 receptor agonistic properties, would prevent Ca 2+ overloading and oxidative stress and upregulate Zn 2+ -based antioxidant defenses, thus enhancing its overall cardioprotective potential in acute stressor state.

Methods: Eight-week-old male Sprague-Dawley rats received a single subcutaneous dose of isoproterenol (1 mg/kg) and compared to those treated with Nebi (10 mg/kg by gavage) for 10 days prior to isoproterenol. SSM were harvested from cardiac tissue at sacrifice. Total Ca 2+ , Zn 2+ and 8-isoprostane levels in tissue, and mitochondrial permeability transition pore (mPTP) opening, free [Ca 2+ ] m and H 2 O 2 production in SSM were monitored. Untreated, age-/sex-matched rats served as controls; each group had six rats and data shown as mean±SEM.

Results: Compared to controls, isoproterenol rats revealed: (1) Significantly (*p<0.05) increased cardiac tissue Ca 2+ (8.2±0.8 vs. 13.7±1.0*, nEq/mg fat-free dry tissue (FFDT)), which was abrogated ( # p<0.05) by Nebi (8.9±0.4 # ); (2) Reduced cardiac Zn 2+ (82.8±2.4 vs. 78.5±1.0*, ng/mg FFDT), but restored by Nebi (82.4±0.6 # ); (3) Two-fold rise in cardiac 8-isoprostane (111.4±13.7 vs. 232.1±17.2*, pmoles/mg protein), and negated by Nebi (122.3+14.5 # ); (4) Greater opening propensity for mPTP that diminished by Nebi; (5) Elevated [Ca 2+ ] m (88.8±2.5 vs. 161.5±1.0*, nM), but normalized by Nebi (93.3±2.7 # ); and (6) Increased H 2 O 2 production by SSM (97.4±5.3 vs. 142.8±7.0*, pmoles/mg protein/min), and nullified by Nebi (106.8±9.0 # ).

Conclusions : Cardioprotection conferred by Nebi, a unique beta-blocker, prevented Ca 2+ overloading and oxidative stress in cardiac tissue and SSM, while simultaneously augmenting antioxidant capacity and promoting mPTP stability. Therapeutic potential of Nebi in patients with acute stressor states remains a provocative possibility that deserves to be explored.

Know Your Audience

Purpose: To identify the chief complaints and demographics at Clinica Esperanza, a student-run free clinic for an underserved Hispanic population. Methods: A retrospective chart review of patient files from 2005 through 2010 was undertaken, as approved by the University of Tennessee Health Science Center’s Institutional Review Board. Results: From 2005 through 2010, Clinica Esperanza fielded 2551 patient visits, consisting of 951 unique patients, 609 females and 342 males. Mean age was 34 years, and 60% of patients presented once, while 13% followed up for 1 year, 9% for 2 years, 6% for 3, 6% for 4, and 4% for 5. “Pap smear,” “abdominal pain,” and “follow-up lab results” ranked, in order, as the 3 top chief complaints. Discussion: Resulting data have led to several improvements. The clinic has remained open weekly to improve patient continuity. With the top 10 chief complaints identified, they are better addressed. More funding is allocated for speculums and proper training of Pap smear technique. Systematic reporting of lab results is being implemented. Physical therapists and pharmacists now participate to address musculoskeletal and medication-based needs, respectively. A volunteer gastroenterologist has been recruited to provide specialized care for abdominal pain. An electrocardiogram machine is now used to evaluate chest pain. To improve student-patient communication, online language learning modules have been created. Conclusions: Based on these data, improvements in health care services have been made, including better continuity, emphasis on top chief complaints, and provider education in medical Spanish. Future plans include on-site pharmacy, smoother referrals, and similar clinics on the University of Tennessee Health Science Center’s other campuses.