A Multimodal Score Accurately Classifies Fontan Failure and Late Mortality in Adult Fontan Patients

Pacemaker-Related Factors and Outcomes of Fontan Patients - Impact of Paced QRS Duration

BACKGROUND

Permanent pacemaker (PPM) implantation has been identified as a risk factor for morbidity and mortality after Fontan operation. This study investigated the factors associated with outcomes in patients with Fontan physiology who underwent PPM implantation.Methods and Results: We retrospectively reviewed 508 patients who underwent Fontan surgery at Asan Medical Center between September 1992 and August 2022. Of these patients, 37 (7.3%) received PPM implantation. Five patients were excluded, leaving 32 patients, of whom 11 were categorized into the poor outcome group. Poor outcomes comprised death, heart transplantation, and "Fontan failure". Clinical, Fontan procedure-related, and PPM-related factors were compared between the poor and good outcome groups. Ventricular morphology, Fontan procedure-associated factors, pacing mode, high ventricular pacing rate, and time from first arrhythmia to PPM implantation did not differ significantly between the 2 groups. However, the poor outcome group exhibited a significantly longer mean paced QRS duration (P=0.044). Receiver operating characteristic curve analysis revealed a paced QRS duration cut-off value of 153 ms with an area under the curve of 0.73 (P=0.035).

CONCLUSIONS

A longer paced QRS duration was associated with poor outcomes, indicating its potential to predict adverse outcomes among Fontan patients.

EASL-ERN position paper on liver involvement in patients with Fontan-type circulation

Fontan-type surgery is the final step in the sequential palliative surgical treatment of infants born with a univentricular heart. The resulting long-term haemodynamic changes promote liver damage, leading to Fontan-associated liver disease (FALD), in virtually all patients with Fontan circulation. Owing to the lack of a uniform definition of FALD and the competitive risk of other complications developed by Fontan patients, the impact of FALD on the prognosis of these patients is currently debatable. However, based on the increasing number of adult Fontan patients and recent research interest, the European Association for The Study of the Liver and the European Reference Network on Rare Liver Diseases thought a position paper timely. The aims of the current paper are: (1) to provide a clear definition and description of FALD, including clinical, analytical, radiological, haemodynamic, and histological features; (2) to facilitate guidance for staging the liver disease; and (3) to provide evidence- and experience-based recommendations for the management of different clinical scenarios.

Anatomical Compliance of Cavopulmonary Assist Device Designs: A Virtual Fitting Study in Fontan Patients

Several device designs for cavopulmonary mechanical circulatory support (MCS) are under investigation, however, challenged by the Fontan population's heterogeneity in size, cardiovascular and thoracic anatomy. This study aimed to preclinically assess the anatomical compliance of proposed device designs in silico. Representative double- and single-outlet cavopulmonary assist device (CPAD) designs were virtually implanted into CT imaging data of 10 patients previously palliated with total cavopulmonary connection (TCPC) for functionally univentricular hearts. Anatomical device compatibility was characterized concerning pump proximity to cardiovascular, respiratory and thoracic structures, as well as pump in- and outflow graft configuration. In 10 Fontan patients with a median age of 10.4 years (interquartile range [IQR] 5.0-15.3 years) and a median body surface area of 1.09 m2 (IQR 0.76-1.28 m2), implantation of a double-outlet CPAD was feasible in 1 patient (10%). In all other, adverse device intersection with the trachea and (neo-)aorta, or posterior pulmonary artery outflow graft kinking were observed. A single-outlet design permitted enhanced device mobilization adapting to individual anatomical conditions, resulting in device fit in nine of 10 patients (90%). Despite vast anatomical variations among single ventricle patients, a single-outlet device design may provide intracorporeal cavopulmonary MCS to a broad spectrum of failing Fontan patients.

Impact of Ventricular Dominance on Long-Term Fontan Outcomes: A 25-year Single-institution Study

BACKGROUND

The long-term impact of ventricular dominance on Fontan outcomes is controversial. This study examined this issue in a 25-year cohort.

METHODS

Patients undergoing the Fontan operation at a single institution (Duke University Medical Center, Durham, NC) from October 1998 to February 2022 were reviewed. Primary outcomes were transplant-free survival and Fontan failure (death, heart transplantation, takedown, protein-losing enteropathy, or plastic bronchitis). Secondary outcomes included hospital and intensive care lengths of stay. Kaplan-Meier methodology compared outcomes by ventricular dominance. Multiphase parametric risk hazard analysis identified risk factors for primary outcomes.

RESULTS

There were 195 patients (104 right ventricular dominant) included in the study. Baseline characteristics were comparable. Perioperative survival was similar (right ventricular dominant, 98%; non-right ventricular dominant, 100%; P = .51). The proportion of patients experiencing death or heart transplantation was 8.7%, and the rate of Fontan failure was 11.8% during a median follow-up of 4.5 years (interquartile range, 0.3-9.8 years). Right ventricular-dominant patients had reduced transplant-free survival (10-year estimates: 80% [95% CI, 70%-91%] vs 92% [95% CI, 83%-100%]; P = .04) and freedom from Fontan failure (73% [95% CI, 62%-86%] vs 92% [95% CI, 83%-100%]; P = .04). Multiphase hazard modeling resolved 2 risk phases. The early phase spanned from surgery to approximately 6 months afterward. The late phase spanned from approximately 6 months after surgery onward. In multivariable analysis, right ventricular dominance was an independent risk factor for death or heart transplantation (parameter estimate, 1.3 ± 0.6; P = .04) and Fontan failure (1.1 ± 0.5; P = .04) during the second phase, with no significant first-phase risk factors.

CONCLUSIONS

Right ventricular dominance was associated with long-term complications after Fontan procedures, including mortality, heart transplantation, and Fontan failure. This cohort may benefit from heightened surveillance in a multidisciplinary Fontan clinic after the perioperative period.

Pregnancy Outcomes in Women after the Fontan Procedure

Women with single ventricle physiology after the Fontan procedure, despite numerous possible complications, can reach adulthood and give birth. Pregnancy poses a hemodynamic burden for distorted physiology of Fontan circulation, but according to the literature, it is usually well tolerated unless the patient is a "failing" Fontan. Our study aimed to assess maternal and fetal outcomes in patients after the Fontan procedure followed up in two tertiary Polish medical centers. We retrospectively evaluated all pregnancies in women after the Fontan procedure who were followed up between 1995-2022. During the study period, 15 women after the Fontan procedure had 26 pregnancies. Among 26 pregnancies, eleven ended with miscarriages, and 15 pregnancies resulted in 16 live births. Fetal complications were observed in 9 (56.3%) live births, with prematurity being the most common complication (n = 7, 43.8%). We recorded 3 (18.8%) neonatal deaths. Obstetrical complications were present in 6 (40%) out of 15 completed pregnancies-two (13.3%) cases of abruptio placentae, two (13.3%) pregnancies with premature rupture of membranes, and two (13.3%) patients with antepartum hemorrhage. There was neither maternal death nor heart failure decompensation during pregnancy. In two (13.3%) women, atrial arrhythmia developed. One (6.7%) patient in the second trimester developed ventricular arrhythmia. None of the patients suffered from systemic thromboembolism during pregnancy. Pregnancy in women after the Fontan procedure is well tolerated. However, it is burdened by a high risk of miscarriage and multiple obstetrical complications. These women require specialized care provided by both experienced cardiologists and obstetricians.

Functional hepatic deterioration determined by 13C-methacetin breath test is associated with impaired hemodynamics and late Fontan failure in adults

Background

Despite improved survival a substantial number of Fontan patients eventually develop late failure. Fontan-associated liver disease (FALD) is the most frequent end-organ dysfunction. Although impaired hemodynamics and Fontan failure correlate with FALD severity, no association between hepatic functional metabolic impairment and Fontan hemodynamics has been established.

Hypothesis

Metabolic liver function measured by liver maximum function capacity test (LiMAx®) correlates with Fontan hemodynamics and Fontan failure.

Methods

From 2020 to 2022, 58 adult Fontan patients [median age: 29.3 years, IQR (12.7), median follow-up time after Fontan operation: 23.2 years, IQR (8.7)] were analyzed in a cross-sectional study. Hemodynamic assessment included echocardiography, cardiopulmonary exercise testing and invasive hemodynamic evaluation. Fontan failure was defined based on commonly applied clinical criteria and our recently composed multimodal Fontan failure score.

Results

LiMAx® test revealed normal maximum liver function capacity in 40 patients (>315 μg/h^*kg). In 18 patients a mild to moderate impairment was detected (140–314 μg/h^*kg), no patient suffered from severe hepatic deterioration (≤ 139 μg/kg^*h). Fontan failure was present in 15 patients. Metabolic liver function was significantly reduced in patients with increased pulmonary artery pressure (p = 0.041. r = −0.269) and ventricular end-diastolic pressure (p = 0.033, r = −0.325), respectively. In addition, maximum liver function capacity was significantly impaired in patients with late Fontan failure (289.0 ± 99.6 μg/kg^*h vs. 384.5 ± 128.6 μg/kg^*h, p = 0.007).

Conclusion

Maximum liver function capacity as determined by LiMAx® was significantly reduced in patients with late Fontan failure. In addition, elevated pulmonary artery pressure and end-diastolic ventricular pressure were associated with hepatic functional metabolic impairment.