What have we learnt 50 years after the first Fontan procedure?

20 years of experience with the Fontan procedure: characteristics and clinical outcomes of children in a tertiary referral hospital

INTRODUCTION

Without participating in a contractile chamber, the Fontan procedure seeks to create a separation of oxygenated and deoxygenated blood in patients with univentricular heart, reducing the risks of long-term hypoxemia and improving their survival. This study describes the clinical outcomes of children undergoing the Fontan procedure between 2000 and 2020 in a tertiary referral hospital care centre in southwestern Colombia.

MATERIALS AND METHODS

A retrospective observational descriptive study. The 81 patients who underwent the Fontan procedure were included. Categorical variables were presented with percentages and continuous variables with measures of central tendency according to the distribution of the data evaluated through the Shapiro-Wilk test. Sociodemographic, clinical, surgical variables, complications, and mortality were described.

RESULTS

Between 2000 and 2020, 81 patients underwent the Fontan procedure: 43 (53.1%) males and a median age of 5.3 years (interquartile range 4.3-6.6). The most common diagnosis was tricuspid atresia (49.4%). The median mean pulmonary arterial pressure was 12 mmHg (interquartile range 10-15), the Nakata index 272 mm2/m2 (interquartile range 204-327), and the McGoon index (interquartile range 1.86-2.3). Seventy-two (88.9%) patients underwent extracardiac Fontan and 44 (54.3%) patients underwent fenestration. The median hospitalisation days were 19 days. The main complication was coagulopathy (19.8%), mortality in the first month between 2000 and 2010 was 8.6%, and after 2010 was 1.2%.

CONCLUSION

The Fontan procedure is a palliative surgery for children with complex heart disease. According to anatomical and physiological variables, the proper choice of patients determines the short- and long-term results.

Pregnancy in Patients with Moderate and Highly Complex Congenital Heart Disease

Although not completely devoid of risk, pregnancy can be managed in virtually all patients affected by even the most complex forms of congenital heart disease. It is not however advisable in patients with any form of pulmonary arterial hypertension. Pregnancy is even manageable in patients with univentricular heart converted to Fontan circulation. A personalised risk stratification should be performed, and patients affected by advanced NYHA functional class appropriately warned of the potential risks. In this setting, metabolomics might represent a novel tool for use in conducting personalised risk stratification. All pregnancies, particularly those at higher risk, should be managed in a tertiary care centre capable of providing the necessary assistance to both the mother and infant. With a few rare exceptions, vaginal delivery is to be preferred over caesarean section due to the lower degree of maternal and foetal complications. The desire for motherhood, at times extreme in women with congenital heart disease, may often be accomplished, thus providing a ray of hope in the lives of these patients.

Micra pacemaker in adult congenital heart disease patients: a case series

INTRODUCTION

implantation of transvenous endocardial or epicardial pacemakers presents specific challenges in adult congenital heart disease (ACHD) patients. Micra leadless pacemaker (Micra PPM) may overcome some of these difficulties.

METHODS

15 ACHD patients who underwent Micra PPM insertion were retrospectively evaluated.

RESULTS

males 53.3%. Mean age at study: 37.5±10.7 years. Mean age at Micra PPM insertion: 35.5±11.0 years. Mean follow-up so far: 2.0±0.3 years. Concerning the ACHD patients, 6.7% had a simple defect, 66.6% had a moderately complex defect, 26.7% were complex. Four patients (26.7%) had a previous PPM implantation. Three patients (20%) had a systemic right ventricle. Two patients (13.3%) had a single ventricle physiology. Five (33.3%) had Trisomy 21. The most commonly used Micra PPM modality was VVI (73.3%). Mean threshold post implantation was 0.48 V [range: 0.25-1.13 V], while mean threshold at 6 months control was 0.60 V [range: 0.38-1.13 V] (p=ns). Mean R wave post implantation was 10.3 V [range: 3.25-19.4 V], whilst mean R wave at 6 months follow-up was 10.1 V [range:3.5-19.0 V] (p=ns). No major peri and post-procedural complications were encountered.

CONCLUSIONS

since ACHD patients are living longer and surviving into adulthood, the incidence of conduction disorders continues to increase, as part of the natural history of some lesions or as early or late complication of surgery. The Micra leadless PPM can be successfully implanted in ACHD patients and have significant theoretical advantages. They should be considered when transvenous and epicardial pacing are either contraindicated or represent an otherwise suboptimal approach. This article is protected by copyright. All rights reserved.

Adequate exercise response at artificial altitude in Fontan patients

PURPOSE

For Fontan-palliated patients, altitude exposure is still a part of discussion since the extent of hypoxic pulmonary vasoconstriction potentially resulting in decreasing cardiac output (Qc), especially during physical exercise, is still unclear. We investigated the effects of normobaric hypoxia (15.2% O₂) simulating 2,500 m above sea level on cardiopulmonary and metabolic parameters and the benefit of daily physical activity (PA) on hypoxic exercise capacity.

METHODS

A total of 21 Fontan patients (14-31 years) and 20 healthy controls performed cardiopulmonary exercise tests on a bicycle ergometer in normoxia and hypoxia until subjective exhaustion, measuring capillary lactate (cLa) every 2 min. In between, participants underwent an activity tracking over 5 days with a triaxial accelerometer.

RESULTS

Hypoxic exercise was well tolerated by Fontan patients, and no adverse clinical events were observed. Fontan patients showed reduced physical capacity under both conditions compared to controls (63% normoxia, 62% hypoxia), but the relative impairment due to hypoxia was similar for both (≈10%). Up to workloads of 2 W/kg oxygen uptake ( V . O₂) and heart rate (HR) developed similarly in patients and controls. cLa increased faster in relation to workload in Fontan patients, but remained significantly lower at peak workload (normoxia 3.88 ± 1.19 mmol/l vs. 7.05 ± 2.1 mmol/l; hypoxia 4.01 ± 1.12 mmol/l vs. 7.56 ± 1.82 mmol/l). Qc was diminished but could be increased similar to controls. Fontan patients with higher PA levels showed a higher V . O_2peak in hypoxia.

CONCLUSION

Exercise during short-time artificial altitude exposure seems to be safe for young Fontan patients. Further studies are needed to validate longer exposure under real conditions. V . O₂, HR, and Qc might not be a limiting factor for exercise until workloads of 2 W/kg. Higher daily PA levels might improve physical capacity under altitude conditions.

Educational attainment in patients with congenital heart disease: a comprehensive systematic review and meta-analysis

BACKGROUND

Our aim was to comprehensively review published evidence on the association between having a congenital heart disease (CHD) compared with not, on educational attainment (i.e. not obtaining a university degree, completing secondary education, or completing any vocational training vs. obtaining/completing) in adults.

METHOD

Studies were eligible if they reported the rate, odds, or proportion of level of educational attainment in adults by whether or not they had a CHD.

RESULT

Out of 1537 articles screened, we identified 11 (N = 104,585 participants, 10,487 with CHD), 10 (N = 167,470 participants, 11,820 with CHD), and 8 (N = 150,813 participants, 9817 with CHD) studies reporting information on university education, secondary education, and vocational training, respectively in both CHD and non-CHD participants. Compared to their non-CHD peers, CHD patients were more likely not to obtain a university degree (OR = 1.38, 95% CI [1.16, 1.65]), complete secondary education (OR = 1.33, 95% CI [1.09, 1.61]) or vocational training (OR = 1.11, 95% CI [0.98, 1.26]). For all three outcomes there was evidence of between study heterogeneity, with geographical area contributing to this heterogeneity.

CONCLUSION

This systematic review identified all available published data on educational attainment in CHD patients. Despite broad inclusion criteria we identified relatively few studies that included a comparison group from the same population, and amongst those that did, few adjusted for key confounders. Pooled analyses suggest evidence of lower levels of educational attainment in patients with CHD when compared to non-CHD peers. The extent to which this may be explained by confounding factors, such as parental education, or mediated by treatments is not possible to discern from the current research literature.