Trends in mortality (1975-2011) after one- and two-stage Fontan surgery, including bidirectional Glenn through Fontan completion

Iron deficiency in patients with a Fontan circulation and its impact on exercise capacity

BACKGROUND

Iron deficiency (ID) has been reported in patients with congenital heart disease. There is, however, a scarcity of data on its prevalence in patients with a Fontan circulation. The aim of this study is to investigate the prevalence of ID in Fontan patients and to investigate the association between ID and exercise capacity in this population.

METHODS AND RESULTS

Blood count and haematological parameters were determined in plasma of 61 Fontan patients (51% female, mean age 29±9 years). ID was defined as transferrin saturation (TSAT) ≤19.8%. The prevalence of ID was 36% (22/61 patients). Especially among women, the diagnosis of ID was highly prevalent (52%) despite normal haemoglobin levels (153.7±18.4 g/L). Mean ferritin levels were 98±80 µg/L and mean TSAT levels were 22%±12%. Cardiopulmonary exercise testing was performed in 46 patients (75%). Patients with ID had a lower peak oxygen uptake (V̇O2peak) (1397±477 vs 1692±530 mL/min; p=0.039), although this relationship was confounded by sex. The presence of ID increased the likelihood of not achieving a respiratory exchange ratio (RER) ≥1.1 by 5-fold (p=0.035).

CONCLUSION

ID is highly prevalent among patients with a Fontan circulation. V̇O2peak is lower in patients with ID. Fontan patients with ID are less likely to achieve an RER≥1.1 during cardiopulmonary exercise testing.

Late outcome of Extracardiac Fontan Patients: 32 years of follow-up

OBJECTIVES

We sought to evaluate the long-term survival and risk factors for morbidity and mortality in our cohort of patients after Extracardiac (EC) Fontan.

METHODS

We collected and analyzed follow-up data until September 2020 for all patients who underwent EC Fontan operation at our institution from November 1988 to November 2015.

RESULTS

Out of 406 patients treated with EC Fontan at a mean age of 5.4 ± 4.5 years, 372 (91.6%) were discharged home; 15% were lost to follow-up. The Median follow-up was 14.6 years (IQR 8.7-20.3). Two hundred patients (54%) had a good long-term outcome, with an event-free long-term survival, but late adverse events of any kind needing interventional or surgical reoperations were reported in 128 patients (34%). Forty-four patients (12%) developed late Fontan failure. Thirty-seven survivors (10%) had late arrhythmias, with the need for pacemaker implantation. Obstruction of the cavopulmonary pathway occurred in forty-nine patients (13%), but just 8 pts needed conduit surgical replacement. At 32 years, the survival probability was 84%. The risk of orthotopic heart transplant (HT), considering death as a competing event, (showed as cumulative incidence) was 12.5%. A preoperative diagnosis of hypoplastic left heart syndrome (HLHS) was an independent risk factor for the need for HT.

CONCLUSIONS

The EC Fontan shows satisfactory long-term survival and low incidence of adverse events and late failure. Conduit replacement is rare, and its longevity may not represent a substantial issue in these patients. However, as with other technical variants, the need for reoperations during long-term follow-up is a significant challenge.

Impact of hypoxemia and re-interventions on clinical outcomes after bidirectional cavopulmonary shunt

OBJECTIVES

We sought to investigate the impact of early postoperative low arterial oxygen saturation on mortality and morbidity after bidirectional cavopulmonary shunt.

METHODS

The medical records of all patients who underwent bidirectional cavopulmonary shunt between 2013 and 2018 were reviewed.

RESULTS

A total of 164 patients were included in this study. Forty-seven patients underwent reintervention during hospital stay at median 7 days after bidirectional cavopulmonary shunt. Before reintervention, 30 patients were intubated or had SpO2 of less than 75%. All re-interventions for Glenn pathway obstruction and 4 out of 5 venovenous coil embolization resulted in hospital discharge, while high mortality was observed after other re-interventions (atrioventricular valve surgery, thrombolysis, systemic ventricular outflow obstruction relief, extracorporeal membrane oxygenation implantation, and diaphragmatic plication). Additional aortopulmonary shunt with pulmonary artery discontinuation was performed in 8 patients who showed severe cyanosis with median SpO2 of 59% under maximal ventilation support. In univariable Cox regression analysis, the associated factors for mortality before total cavopulmonary connection were reduced ventricular function (HR 6.89, 95% CI 1.76-26.9, P value 0.006), greater than moderate atrioventricular valve regurgitation (HR 5.89, 95% CI 1.70-20.4, P value 0.005), SpO2 1 hour after extubation (HR 0.87, 95% CI 0.80-0.96, P value 0.004), and mean pulmonary artery pressure 1 hour after extubation (HR 1.14, 95% CI 1.02-1.26, P value 0.016).

CONCLUSIONS

After bidirectional cavopulmonary shunt, unacceptable cyanosis persisted with various etiologies. Low arterial oxygen saturation within 1 hour after extubation is significantly associated with high mortality after bidirectional cavopulmonary shunt.

Long-term outcomes of atrioventricular septal defect and single ventricle: A multicenter study

OBJECTIVE

The study objective was to analyze survival and incidence of Fontan completion of patients with single-ventricle and concomitant unbalanced atrioventricular septal defect.

METHODS

Data from 4 Dutch and 3 Belgian institutional databases were retrospectively collected. A total of 151 patients with single-ventricle atrioventricular septal defect were selected; 36 patients underwent an atrioventricular valve procedure (valve surgery group). End points were survival, incidence of Fontan completion, and freedom from atrioventricular valve reoperation.

RESULTS

Median follow-up was 13.4 years. Cumulative survival was 71.2%, 70%, and 68.5% at 10, 15, and 20 years, respectively. An atrioventricular valve procedure was not a risk factor for mortality. Patients with moderate-severe or severe atrioventricular valve regurgitation at echocardiographic follow-up had a significantly worse 15-year survival (58.3%) compared with patients with no or mild regurgitation (89.2%) and patients with moderate regurgitation (88.6%) (P = .033). Cumulative incidence of Fontan completion was 56.5%, 71%, and 77.6% at 5, 10, and 15 years, respectively. An atrioventricular valve procedure was not associated with the incidence of Fontan completion. In the valve surgery group, freedom from atrioventricular valve reoperation was 85.7% at 1 year and 52.6% at 5 years.

CONCLUSIONS

The long-term survival and incidence of Fontan completion in our study were better than previously described for patients with single-ventricle atrioventricular septal defect. A concomitant atrioventricular valve procedure did not increase the mortality rate or decrease the incidence of Fontan completion, whereas patients with moderate-severe or severe valve regurgitation at follow-up had a worse survival. Therefore, in patients with single-ventricle atrioventricular septal defect when atrioventricular valve regurgitation exceeds a moderate degree, the atrioventricular valve should be repaired.

The multisystem nature of isomerism: left isomerism complicated by Abernethy malformation and portopulmonary hypertension

Isomerism, also referred to as "heterotaxy" is a complex set of anatomic and functional perturbations. One of the most obvious manifestations of isomerism is the disturbance of organ arrangement, such that the thoracic organs are no longer asymmetric on the left and right. We report the case of a 14-year-old female in whom exercise-induced dyspnea led to a late diagnosis of left isomerism complicated by Abernethy malformation and portopulmonary hypertension. A comprehensive evaluation revealed two anatomic left lungs and hyparterial bronchi, bilateral left atria, an interrupted inferior caval vein with azygos continuation, multiple spleens, sinus node dysfunction, hepatic hypertrophy with focal nodular hyperplasia, and absence of the portal vein. Pulmonary vasodilator therapy was initiated resulting in clinical improvement. This case exhibits unique features including a late diagnosis of isomerism with Abernethy malformation and portopulmonary hypertension. The patient's presentation, medical workup, and future treatment emphasise the importance of multidisciplinary care in children with complex multisystem disease. We review the multiple cardiac and extracardiac manifestations of isomerism.

Outcomes of single ventricle palliation in infants with heterotaxy syndrome

 

OBJECTIVES

Heterotaxy is a known risk factor for morbidity and mortality in single ventricle palliation. In this study, we examined our experience with this challenging group of patients.

METHODS

Records of patients born between 2001 and 2019 with heterotaxy, who needed staged single ventricle palliation were retrospectively analysed.

RESULTS

A total of 53 patients were included in this study. Thirty-five (66%) patients had a right ventricular dominance, common atrioventricular septal defect was present in 37 (70%) patients. Anomalous pulmonary venous drainage was present in 29 (55%) patients. Forty-six (86%) patients underwent first-stage palliation. Forty-one (77.3%) patients received a bidirectional cavopulmonary connection. Thirty-one (58%) patients received total cavopulmonary connection (TCPC). Overall survival rate was 92% at 1 month, 74% at 1 year and 68% at 10 years. Twelve (22.6%) patients died before second palliation stage. Four (10%) patients died before TCPC. No patient died after TCPC. Independent risk factors for mortality in the multivariate COX regression were a presence of restrictive pulmonary blood flow (HR 3.23; 95% CI 1.02-10.2; P = 0.05) and greater than mild atrioventricular valve regurgitation (HR 3.57; 95% CI 1.27-10.0; P = 0.02).

CONCLUSIONS

Mortality and morbidity in patients with single ventricle and heterotaxy are high. Restrictive pulmonary blood flow needing early modulation and greater than mild atrioventricular valve regurgitation at presentation are independent risk factors for mortality. Total anomalous pulmonary venous connection was not identified as a risk factor in the current era.

N-terminal pro-brain natriuretic peptide serum levels reflect attrition of the Fontan circulation

OBJECTIVE

N-terminal pro-brain natriuretic peptide has an established role in the diagnosis and prognosis of heart failure. In Fontan patients, this peptide is often increased, but its diagnostic value in this particular non-physiologic, univentricular circulation is unclear. We investigated whether N-terminal pro-brain natriuretic peptide represents ventricular function or other key variables in Fontan patients.

METHODS AND RESULTS

Ninety-five consecutive Fontan patients ≥10 years old who attended the outpatient clinic of the Center for Congenital Heart Diseases in 2012-2013 were included. Time since Fontan completion was 16 ± 9 years. Median N-terminal pro-brain natriuretic peptide was 114 (61-264) ng/l and was higher than gender-and age-dependent normal values in 54% of the patients. Peptide Z-scores were higher in patients in NYHA class III/IV compared to those in class I/II, but did not correlate with ventricular function assessed by MRI and echocardiography, nor with peak exercise capacity. Instead, peptide Z-scores significantly correlated with follow-up duration after Fontan completion (p < 0.001), right ventricular morphology (p = 0.004), indexed ventricular mass (p = 0.001), and inferior caval vein diameter (p < 0.001) (adjusted R2 = 0.615).

CONCLUSIONS

N-terminal pro-brain natriuretic peptide levels in Fontan patients correlate with functional class, but do not necessarily indicate ventricular dysfunction. Increased peptide levels were associated with a longer existence of the Fontan circulation, morphologic ventricular characteristics, and signs of increased systemic venous congestion. Since the latter are known to be key determinants of the performance of the Fontan circulation, these findings suggest increase in N-terminal pro-brain natriuretic peptide levels to indicate attrition of the Fontan circulation, independent of ventricular function.

Liver Strain Using Feature Tracking of Cine Cardiac Magnetic Resonance Imaging: Assessment of Liver Dysfunction in Patients with Fontan Circulation and Tetralogy of Fallot

We propose a novel method to quantify pulsatile liver deformation using the feature tracking method of cardiac cine magnetic resonance imaging (MRI) and investigate its association with liver dysfunction in long-term postoperative patients after Fontan and intracardiac repair for the tetralogy of Fallot (TOF). Standard cine MRI which was previously performed for cardiac evaluation of 85 patients who underwent Fontan operation (mean age, 22.9 years), 43 patients with TOF (mean age, 34.6 years), and 32 healthy controls (mean age, 42.3 years) were retrospectively analyzed. Pulsatile liver deformation in the craniocaudal direction was calculated using the feature tracking method of cardiac cine imaging derived from cine-balanced turbo field-echo sequences performed on a 1.5 Tesla MR scanner, and was defined as liver strain. The liver strain was compared across the three patient groups using one-way analysis of variance. Liver dysfunction by a liver strain were compared using the Mann-Whitney U test. Liver strain for patients who underwent Fontan operation and TOF patients was significantly lower than controls (Fontan, 13.3 ± 6.5%; TOF, 15.0 ± 11.2%; controls, 23.1 ± 10.2%, p < 0.0001). In Fontan and TOF patients, MELD score was significantly greater for patients with a liver strain < 15% than those with values > 15% (5.9 ± 5.8 vs. 2.9 ± 2.9, p < 0.001). Lower liver strain values were found in adolescent and adult patients after Fontan operation and TOF, and correlates with the severity of liver injury, expressed as MELD score. Our method can evaluate hepatic function in adult congenital heart disease, together with the assessment of cardiac function.

Percutaneous liver biopsy in Fontan patients

BACKGROUND

Patients who have undergone the Fontan operation for palliation of congenital heart disease with single-ventricle pathophysiology are at high risk for developing progressive liver fibrosis. Pathological assessment from percutaneous liver biopsy is central to the management of Fontan-associated liver disease, but liver biopsy in this vulnerable population poses unique challenges and potential risks.

OBJECTIVE

This retrospective study describes our experience with percutaneous liver biopsy performed to assess changes of Fontan-associated liver disease, with particular regard to procedural outcomes.

MATERIALS AND METHODS

Data from liver biopsy procedure reports, pathology reports, cardiac angiography pressure measurements and laboratory values of patients with single ventricle heart disease after the Fontan operation who underwent ultrasound-guided percutaneous liver biopsy performed in interventional radiology at a pediatric tertiary care center during a 3-year period were retrospectively analyzed.

RESULTS

Sixty-eight liver biopsies were performed in 67 patients (mean age: 20.2 years, range: 7.2-39 years). The technical success rate was 100%, and tissue was adequate for assessing liver disease in 100% of the procedures, including biopsies performed with a single pass. Anticoagulation was routinely suspended before biopsy, and no cardiac complications were encountered due to this suspension. A coaxial biopsy system using an 18-gauge (G) full-core instrument through a 17-G introducer trocar was most commonly used, in 41/68 cases (60%). The most common trough length was 2.3 cm, used in 37 cases (54%). One pass was made in 27 procedures (40%) and two passes in 30 (44%); tract embolization with gelatin sponge was performed in 52 (76%). The only complication was hemorrhage, which occurred in 5/68 (7.4%) of the biopsies, minor in four (5.9%) and major in one (1.5%) -- similar to rates reported for liver biopsy in non-Fontan patients. Hemorrhage had a delayed presentation in three of these five cases. Immediate post-biopsy hemoglobin decrease of ≥2 mg/dL showed a low sensitivity for hemorrhage. The mean Fontan pressure measured during cardiac angiography was 13.8 mmHg, and shunt pressures were not associated with an increased risk of hemorrhage.

CONCLUSION

Percutaneous liver biopsy in Fontan patients can be performed safely with high technical success rates and without increased complication rates. Meticulous technique and close observation are recommended to reduce post-biopsy complications. The degree of right heart pressure elevation was not associated with hemorrhage.

Quality of life and sexual well-being in patients with a Fontan circulation: An explorative pilot study with a mixed method design

OBJECTIVE

To get an impression of the quality of life (QOL) and sexual well-being in the Fontan population, and to generate hypotheses for future research.

METHODS

For this cross-sectional pilot study, questionnaires regarding health-related QOL, sexual function and fertility/pregnancy were completed by 21 patients with a Fontan circulation >16 years old, followed at the University Medical Center Groningen, the Netherlands. Semi-structured qualitative interviews were conducted in 8 patients.

RESULTS

Fontan patients scored significantly lower on general health than their healthy peers (t(19)=-3.0, P = .008), whereas their scores on other QOL domains and sexual well-being were comparable to normal values. During childhood, most patients experienced physical limitations and the feeling of being an outsider, and frequently faced bullying. Regarding sexual well-being, large interindividual differences were noted. Four interviewed patients (25-30 years) reported a good sexual well-being, whereas the other interviewed patients (33-47 years) reported erectile dysfunction, low self-esteem and avoidance of sexual intercourse. Both the QOL domains mental health and role restrictions due to emotional problems were associated with female avoidance (P = .083, respectively, P = .089) and dyspareunia (P = ns respectively P = .094). In males, role restrictions due to physical problems and health change were related to sexual dissatisfaction (P = .056) respectively nonsensuality (P = .025).

CONCLUSIONS

Overall, Fontan patients have a relatively preserved quality of life and sexual wellbeing but face more social isolation and bullying during childhood/adolescence than their healthy peers. Sexual problems were mainly associated with physical limitations in males and with psychosocial limitations in females. Finally, sexual dysfunction was more common in older Fontan patients, and future research has to clarify whether progressive attrition of the Fontan circulation affects the patients' QOL and sexual well-being.

Intracardiac anatomical relationships and potential for streaming in double inlet left ventricles

The aim of this study was to gain better understanding of the variable anatomical features of double inlet left ventricle hearts without cavopulmonary connection that would potentially facilitate favorable streaming. Thirty-nine post-mortem specimens of double inlet left ventricle without cavopulmonary connection were investigated. The focus was on anatomical characteristics that could influence the flow and separation of deoxygenated and oxygenated blood in the ventricles. Elements of interest were the ventriculoarterial connection, the spatial relationship of the ventricles, the position and size of the great arteries, the ventricular septal defect, the presence of relative outflow tract stenosis and the relationship of the inflow and outflow tracts. The most common anatomy was a discordant ventriculoarterial connection with an anatomically left-sided morphologically right ventricle (n = 12, 31%). When looking at the pulmonary trunk/aorta ratio, 21 (72%) hearts showed no pulmonary stenosis relative to the aorta. The ventricular septal defect created a relative subpulmonary or subaortic stenosis in 13 (41%) cases. Sixteen (41%) hearts had a parallel relationship of the inflow and outflow tracts, facilitating separation of deoxygenated and oxygenated blood streams. On the other end of the spectrum were 10 (25%) hearts with a perpendicular relationship, which might lead to maximum mixing of the blood streams. The relationship of the inflow and outflow tracts as well as the presence of (sub-) pulmonary stenosis might play a crucial role in the distribution of blood in double inlet left ventricle hearts. Additional in vivo studies will be necessary to confirm this postulation.

Risk Factors For Unfavorable Outcomes After Bidirectional Cavopulmonary Anastomosis

Background:

Bidirectional cavopulmonary anastomosis (BCPA) is an important preliminary step toward the Fontan procedure; thus, understanding of risk factors for morbidity and mortality after BCPA may ultimately promote improved rates of success with Fontan completion and general survival. This study evaluated survival and predictors of unfavorable outcomes in patients after BCPA.

Methods:

Clinical data of 157 patients who underwent BCPA from 2003 to 2015 at a single center were retrospectively analyzed.

Results:

Three-year and nine-year survival after BCPA were 87.1% ± 2.8% and 85.8% ± 2.9%, respectively. Freedom from unfavorable outcomes (mortality, BCPA takedown, nonsuitability for Fontan procedure) was 83.8% ± 3.1% at three years and 73.5% ± 4.8% at nine years. Multivariate proportional hazards regression analysis revealed that total anomalous pulmonary venous connection (TAPVC; hazard ratio [HR]: 3.74, 95% confidence interval [CI]: 1.35-10.36; P = .01) and increased mean pressure in BCPA circuit (HR: 1.17, 95% CI: 1.02-1.34; P = .03) were independent risk factors for unfavorable outcomes. Postoperative mean pressure in BCPA circuit in patients with poor outcomes was median 16 mm Hg (interquartile range [IQR]: 14-18 mm Hg) versus median 14 mm Hg (IQR: 12-15.5 mm Hg) in patients with favorable outcomes ( P < .01). Preoperative (HR: 1.87, 95% CI: 1.20-2.91; P < .01) and postoperative atrioventricular valve regurgitation (AVVR; HR: 2.22, 95% CI: 1.24-3.94; P < .01) were also associated with unfavorable outcome in univariate Cox regression.

Conclusions:

Elevated mean pressure in the BCPA circuit is the main predictor of unfavorable outcome; therefore, thorough preoperative examination and careful patient selection are critical points for successful intermediate-stage and later Fontan completion. Total anomalous pulmonary venous connection and insufficient correction of AVVR worsen the prognosis in this patient group.

Fontan Circulation over Time

The unique, unphysiological Fontan circulation is associated with an impaired functional status of the patients that is suggested to deteriorate over time. Unfortunately, previous studies did not integrate both pulmonary and cardiac determinants of functional status. In addition, a comparison with the natural decrease in exercise capacity in healthy subjects (in both children and adults) is lacking. This single-center study aims to investigate the functional status in a cohort of Fontan patients in relation to time since Fontan completion and to identify its determinants, including cardiac characteristics and pulmonary characteristics. Eighty-five consecutive Fontan patients ≥10 years who performed adequate cardiopulmonary exercise testing (respiratory exchange ratio >1.01) were included. Mean time since Fontan completion was 15 ± 9 years (range 2 to 37 years). New York Heart Association functional class was I in 36 patients (42%), II in 41 patients (48%), and III in 8 patients (9%). Peak oxygen uptake during exercise (VO₂ index) was 25.7 ± 7.9 ml/min/m² (58 ± 14% of predicted). New York Heart Association functional class and peak VO₂ index both correlated with time since the Fontan operation; however, peak VO₂ as percentage of predicted (VO₂(pred)) did not. In multivariate analyses, peak VO₂(pred) was independently associated with maximum heart rate, oxygen pulse at peak exercise, and forced expiratory volume in 1 second (R² = 0.579) but not with cardiac output in rest. In conclusion, the present data suggest that functional status in Fontan patients is impaired already shortly after Fontan completion, whereas its subsequent deterioration seems to follow the natural decline of aging. Furthermore, functional status in Fontan patients correlates with pulmonary function and cardiac functional parameters during exercise but not with conventional cardiac measurements at rest.

Lessons Learned From a Critical Analysis of the Fontan Operation Over Three Decades in a Single Institution

Background:

The Fontan operation (FO) has evolved and many centers have demonstrated improved results relative to those from earlier eras. We report a single-institution experience over three decades, describing the outcomes and evaluating risk factors.

Methods:

Successive patients undergoing primary FO were divided into era I (1984-1994), era II (1995-2004), and era III (2005-2014). Clinical and operative notes were reviewed for demographic, anatomic, and procedure details. End points included early and late mortality and a composite of death, heart transplantation (HTX), or Fontan takedown.

Results:

A total of 420 patients underwent 18 atriopulmonary connections, 82 lateral tunnels (LT), and 320 extracardiac conduit (EC) Fontan procedures. Forty-six (11%) patients died; early and late mortality were 7.9% and 3.1%, respectively. Eight (1.9%) patients underwent HTX, 11 (2.6%) underwent Fontan conversion to EC, and 1 (0.2%) takedown of EC to bidirectional Glenn shunt. Prevalence of concomitant valve surgery ( P < .001) and pulmonary artery reconstruction ( P < .001) differed over the eras. Preoperative valve regurgitation was associated with likelihood of early mortality (odds ratio [OR] = 3.5, P = .002). Embolic events (OR = 1.9, P = .047), preoperative valve regurgitation (OR = 2.3, P = .029), diagnosis of unbalanced atrioventricular canal defect (OR = 1.14, P = .03), and concomitant valve replacement (OR = 6.9, P = .001) during the FO were associated with increased risk of the composite end point (death, HTX, or takedown).

Conclusion:

Technical modifications did not result in improved results across eras, due in part to more liberal indications for surgery in the recent years. Valve regurgitation, unbalanced atrioventricular canal, embolic events, or concomitant valve replacement were associated with FO failure.

Bidirectional cavopulmonary anastomosis with additional pulmonary blood flow: good or bad pre-Fontan strategy

Objectives

This study aimed to evaluate the influence of preserved additional pulmonary blood flow (APBF) on survival after bidirectional cavopulmonary shunt (BCPS) and completion of Fontan circulation.

Methods

From March 2003 and April 2015, 156 patients with a single ventricle underwent BCPS. After performing propensity score analysis (1:1) for the entire sample, 50 patients with APBF (APBF group) were matched with 50 patients without APBF (no-APBF group).

Results

Age ( P  = 0.90), sex ( P  = 0.57), weight ( P  = 0.75), single ventricle morphology ( P =  0.87), type of neonatal palliative procedure ( P =  0.52), saturation ( P =  0.35), ejection fraction ( P =  0.90), Nakata index ( P  = 0.70) and mean pulmonary artery pressure ( P  = 0.72) were not significantly different between the groups. No significant survival difference was demonstrated ( P  = 0.54). One and 4-year survival rates were both 89.1% ± 4.6% in the APBF group and 87.2% ± 4.9% and 83.4% ± 5.9%, respectively, in the no-APBF group. There was no significant difference in rates of Fontan completion ( P  = 0.24), which was achieved in 22 patients from the APBF group (55.0%) and 26 patients from the no-APBF group (65.0%). However, Fontan completion occurred significantly earlier in the no-APBF group ( P  < 0.01). In this group, Fontan procedure was performed before 36 months of inter-stage period in 45.9% ± 8.5% of cases (95% CI 31.0-63.7%) compared to only 13.3 ± 5.6% (95% CI 5.8-29.1%) in the APBF group.

Conclusions

Our study demonstrates that APBF does not affect survival after BCPS or Fontan completion rate. APBF allows postponing the Fontan procedure without a negative effect on clinical status.

Diminished liver microperfusion in Fontan patients: A biexponential DWI study

It has been demonstrated that hepatic apparent diffusion coefficients (ADC) are decreasing in patients with a Fontan circulation. It remains however unclear whether this is a true decrease of molecular diffusion, or rather reflects decreased microperfusion due to decreased portal blood flow. The purpose of this study was therefore to differentiate diffusion and microperfusion using intravoxel incoherent motion (IVIM) modeled diffusion-weighted imaging (DWI) for different liver segments in patients with a Fontan circulation, compare to a control group, and relate with liver function, chronic hepatic congestion and hepatic disease. For that purpose, livers of 59 consecutively included patients with Fontan circulation (29 men; mean-age, 19.1 years) were examined (Oct 2012─Dec 2013) with 1.5T MRI and DWI (b = 0,50,100,250,500,750,1500,1750 s/mm²). IVIM (D_slow, D_fast, f_fast) and ADC were calculated for eight liver segments, compared to a control group (19 volunteers; 10 men; mean-age, 32.9 years), and correlated to follow-up duration, clinical variables, and laboratory measurements associated with liver function. The results demonstrated that microperfusion was reduced (p<0.001) in Fontan livers compared to controls with ─38.1% for D_fast and ─32.6% for f_fast. Molecular diffusion (D_slow) was similar between patients and controls, while ADC was significantly lower (─14.3%) in patients (p<0.001). ADC decreased significantly with follow-up duration after Fontan operation (r = ─0.657). D_slow showed significant inverse correlations (r = ─0.591) with follow-up duration whereas D_fast and f_fast did not. From these results it was concluded that the decreasing ADC values in Fontan livers compared with controls reflect decreases in hepatic microperfusion rather than any change in molecular diffusion. However, with the time elapsed since the Fontan operation molecular diffusion and ADC decreased while microperfusion remained stable. This indicates that after Fontan operation initial blood flow effects on the liver are followed by intracellular changes preceding the formation of fibrosis and cirrhosis.

Characteristics of Hospitalizations for the Glenn Procedure in Those With Isomerism Compared to Those Without

Isomerism, also known as heterotaxy, is a unique clinical entity in which there are mirror imaged findings in the thoracic. In the abdomen, the arrangement of organs can be random. The anatomic findings also have functional consequences. Isomerism has been known to increase morbidity and mortality in those with functionally univentricular hearts. The aim of this study was to determine the impact of isomerism on the Glenn hospitalization. Data from the 1997 to 2012 Kids' Inpatient Database were utilized for this cross-sectional study. Admissions during which a Glenn procedure was done were identified. Next, these admissions were separated into those with and without isomerism. Admission characteristics were then compared in a univariate fashion as well as by regression analysis. Length of hospitalization, cost of hospitalization, extracorporeal membrane oxygenation, and inpatient mortality were the outcomes of interest. A total of 4959 admissions with a Glenn procedure were identified. Of these, 450 were associated with isomerism. The median age at which the Glenn procedure was done was 10 and 13 months in those without and with isomerism, respectively. Neither univariate nor regression analysis demonstrated any significant difference in length of hospitalization, cost of hospitalization, need for extracorporeal membrane oxygenation, and inpatient mortality between those with and without isomerism. Isomerism does not impact the characteristics of the Glenn hospitalization. Those with isomerism did tend to be older when they underwent the Glenn procedure.

Risk Factors for Longer Hospital Stay Following the Fontan Operation

OBJECTIVES

Children with functional single ventricle undergoing the Fontan operation consume considerable resources. The purpose of this study is to evaluate pre- and intraoperative risk factors for longer hospital stay and to describe the perioperative course at a single institution over a 15-year period.

DESIGN

Retrospective cohort study.

SETTING

A single pediatric cardiac ICU.

PATIENTS

All consecutive patients undergoing a first-time Fontan operation from 2000 to 2014.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Prolonged length of stay was defined as hospital stay greater than 75 percentile at our institution after surgery. Of 218 patients who met inclusion criteria, median length of stay was 10 days (interquartile range, 8-14 d); prolonged length of stay was defined greater than or equal to 15 days. Independent pre- and intraoperative risk factors for prolonged length of stay included higher hemoglobin (odds ratio, 1.29; p = 0.003), higher mean pulmonary artery pressure (odds ratio, 1.14; p = 0.037), and lower aortic saturation (odds ratio, 0.92; p = 0.008) in the entire group. When patients with hepatic vein inclusion (following previous Kawashima) were excluded, higher hemoglobin (odds ratio, 1.24; p = 0.027), lower aortic saturation (odds ratio, 0.92; p = 0.017), and placement of a fenestration (odds ratio, 2.438; p = 0.021) were associated with prolonged length of stay. Fifty-eight patients (26.6%) had major complications defined by Pediatric Cardiac Critical Care Consortium. Placement of a fenestration (odds ratio, 2.297; p = 0.014) and longer aortic cross-clamp time (odds ratio, 1.015; p = 0.003) were independently associated with Pediatric Cardiac Critical Care Consortium major complications.

CONCLUSIONS

In this series, 75% of patients had a postoperative length of stay less than or equal to 2 weeks. Preoperative factors suggesting worse hypoxemia/decreased pulmonary blood flow (higher hemoglobin and lower oxygen saturation) and increased pulmonary artery pressure were associated with prolonged length of stay. These findings may help risk stratify this complex patient population, provide more accurate family counseling, and provide preliminary data for changes in preoperative timing of the Fontan and/or changes to postoperative management strategies for those at high risk for increased ICU morbidity.

Outcomes of total cavopulmonary connection for single ventricle palliation

BACKGROUND

The aim of this study was to review the early and mid-term outcomes of the total cavopulmonary connection (TCPC) procedure and evaluate risk factors for prolonged pleural effusions.

METHODS

The clinical records of 82 consecutive patients, who underwent a TCPC operation between January 2008 and December 2013, were reviewed for incidence of prolonged pleural effusions, duration of ventilation time and pleural drainage, length of intensive care unit (ICU) stay, and early and mid-term morbidity and mortality.

RESULTS

The median age at surgery was 3.0 years. The main single ventricle diagnoses included 18 cases of a double-inlet single ventricle, 17 cases of heterotaxy, 16 cases of tricuspid atresia, 4 cases of mitral atresia, 12 cases of unbalanced complete atrioventricular canal (CAVC), 5 cases of double-outlet right ventricle (DORV) combined with ventricular septal defect (VSD) and pulmonary stenosis (PS), 4 cases of transposition of the great arteries (TGA) combined with VSD and PS, 4 cases of corrected transposition of great arteries (cTGA) combined VSD and PS, and 2 cases of criss-cross heart. Preoperative mean pulmonary artery pressure (mPAP) was 13.66±2.21 mmHg with 23.2% (n=19) higher than 15 mmHg. A total of 61 (74.4%) patients underwent a fenestration. The perioperative mortality was 4.9%. The median duration of pleural effusion was 10 days (range, 3-80 days), and prolonged pleural effusions occurred in 16 (19.5%) patients. Multivariable analysis revealed that mPAP >15 mmHg was independently associated with prolonged pleural effusions (OR, 8.33; 95% CI, 2.33-29.74; P=0.001), and creation of a fenestration was associated with decreased odds of effusion (OR, 0.21; 95% CI, 0.06-0.74; P=0.015). Five-year estimated Kaplan-Meier survival of two-stage TCPC was significantly higher than that of one-stage group(96.7% vs. 79.7%, P=0.023). Patients with heterotaxy or obstructed totally anomalous pulmonary venous connection (TAPVC) had significantly worse mid-term survival.

CONCLUSIONS

Staged TCPC improved the early and mid-term survival of patients with a single ventricle. mPAP >15 mmHg was independently associated with prolonged pleural effusions and a fenestration significantly associated with a lower odds of effusion.

High Overweight and Obesity in Fontan Patients: A 20-Year History

The prevalence of obesity in long-term survivors with complex congenital heart disease may be increasing, and little is known about the timing and onset of weight gain and growth patterns in these high-risk patients. Prevalence rates of overweight/obesity and longitudinal changes in body mass index (BMI) with age were determined in 606 patients with Fontan circulation seen at a tertiary care cardiology center from 1992 to 2012. The number of clinic encounters (n) was stratified by age group (n = 401, 2-5 years; n = 333, 6-11 years; n = 217, 12-19 years; and n = 129, >20 years). Among adults, 39% were overweight/obese at last clinic visit; 22% overweight, and 17% obese. Childhood anthropometric data were available for 82 adults, of which 15% (n = 12/82) were overweight/obese in childhood. The likelihood of being overweight/obese as an adult was three times higher if there was a BMI ≥ 85th percentile in childhood (CI 2.1-4.5, P < 0.01). Overweight/obesity in adulthood was associated with lower heart failure rates (4 vs. 19%, P = 0.03). Pediatric rates of overweight/obesity were comparable to national data (NHANES 2011-2012) in every age group: at 2-5 years, (25 vs. 23%), 6-11 years (26 vs. 34%), and 12-19 years (15 vs. 35%). Systolic blood pressure was higher in overweight/obese children as young as 2-5 years of age. Childhood and adult survivors with Fontan circulation have high rates of overweight/obesity. Childhood obesity is a strong predictor of future adiposity and is linked to changes in systolic blood pressure at a very young age.

The Fontan circulation and the liver: A magnetic resonance diffusion-weighted imaging study

BACKGROUND

Patients with a Fontan circulation tend to develop liver fibrosis, liver cirrhosis and even hepatocellular carcinoma. The aim of this study is to use the magnetic resonance technique diffusing-weighted imaging (DWI) for detecting liver fibrosis/cirrhosis in Fontan patients and to establish whether DWI results are associated with functional aspects of the Fontan circulation.

METHODS

In a cross-sectional study, 59 Fontan patients were evaluated by liver DWI. The association between apparent diffusion coefficients (ADC) and patient characteristics, laboratory measurements and functional aspects of the Fontan circulation (NYHA class, maximum oxygen uptake during exercise and cardiac index) was assessed.

RESULTS

Liver ADC values were low (0.82×10(-3)±0.11×10(-3) mm2/s) compared with literature values for healthy volunteers and correlated negatively with calculated liver fibrosis/cirrhosis scores (Fib-4 score, p=0.019; AST/ALT ratio, p=0.009) and gamma-glutamyl transferase (p=0.001). Furthermore, ADC values correlated negatively with follow-up duration (p<0.001) and positively with cardiac index (p=0.019). No correlation between ADC values and exercise tests was found. In multivariable analysis, the ADC values were independently correlated with follow-up duration after Fontan completion.

CONCLUSIONS

The results of the current study suggest that progressive liver damage due to chronic congestion and potential hypoperfusion is reflected in the liver ADC values in Fontan patients. This study highlights that liver damage in the context of the Fontan circulation might be far more common than previously thought, and that the implementation of liver assessment in the routine follow-up of Fontan patients is recommendable.

Children after fontan have strength and body composition similar to healthy peers and can successfully participate in daily moderate-to-vigorous physical activity

The objective of this study was to evaluate the active lifestyle capacity (daily physical activity, strength, flexibility, body composition) of children after the Fontan procedure; hypothesized to be lower than healthy peers. Participants (n = 64, 25 females) were 9.0 ± 1.7 years of age (range 6.0-11.7 years). Fontan completion occurred at 3.3 ± 1.4 years of age (5.7 ± 2.0 years prior). Canadian Health Measures Survey protocols assessed aerobic endurance (paced walking up/down steps), strength (handgrip), flexibility (sit and reach), body composition (body mass index), and daily moderate-to-vigorous physical activity (7-day accelerometry). Difference scores compared participant data to published norms (t tests). Linear regression evaluated age/gender/demographic factor associations. Children after Fontan had strength scores similar (mean difference 1.1 kg) to their peers were less likely to be obese (mean difference of body mass index = 1.1 ± 2.5, p = 0.001) and performed 50 min of moderate-to-vigorous activity (MVPA) per day (12 ± 17 min/day below healthy peers, p < 0.001). Estimated peak endurance (61 % of expected) and flexibility (64 % of expected) were lower than peers (p < 0.001). Almost all (60/63) participants demonstrated the capacity to perform at least 20 min of MVPA per day. Difference from norms was smaller among children younger at Fontan completion (4 ± 2 min/year) and taking antithrombotic medication (7 ± 18 and 22 ± 17 min/day for taking/not taking, respectively). Children after Fontan demonstrate the capacity for the daily physical activity associated with optimal health. They have similar strength and good body composition. We recommend that children after Fontan be counselled that they can successfully participate in healthy, active lifestyles and physically active peer play.

Favourable mid-term outcome after heart transplantation for late Fontan failure

OBJECTIVES

Fontan failure (FF) represents a growing and challenging indication for paediatric orthotopic heart transplantation (OHT). The aim of this study was to identify predictors of the best mid-term outcome in OHT after FF.

METHODS

Twenty-year multi-institutional retrospective analysis on OHT for FF.

RESULTS

Between 1991 and 2011, 61 patients, mean age 15.0 ± 9.7 years, underwent OHT for failing atriopulmonary connection (17 patients = 27.8%) or total cavopulmonary connection (44 patients = 72.2%). Modality of FF included arrhythmia (14.8%), complex obstructions in the Fontan circuit (16.4%), protein-losing enteropathy (PLE) (22.9%), impaired ventricular function (31.1%) or a combination of the above (14.8%). The mean time interval between Fontan completion and OHT was 10.7 ± 6.6 years. Early FF occurred in 18%, requiring OHT 0.8 ± 0.5 years after Fontan. The hospital mortality rate was 18.3%, mainly secondary to infection (36.4%) and graft failure (27.3%). The mean follow-up was 66.8 ± 54.2 months. The overall Kaplan-Meier survival estimate was 81.9 ± 1.8% at 1 year, 73 ± 2.7% at 5 years and 56.8 ± 4.3% at 10 years. The Kaplan-Meier 5-year survival estimate was 82.3 ± 5.9% in late FF and 32.7 ± 15.0% in early FF (P = 0.0007). Late FF with poor ventricular function exhibited a 91.5 ± 5.8% 5-year OHT survival. PLE was cured in 77.7% of hospital survivors, but the 5-year Kaplan-Meier survival estimate in PLE was 46.3 ± 14.4 vs 84.3 ± 5.5% in non-PLE (P = 0.0147). Cox proportional hazards identified early FF (P = 0.0005), complex Fontan pathway obstruction (P = 0.0043) and PLE (P = 0.0033) as independent predictors of 5-year mortality.

CONCLUSIONS

OHT is an excellent surgical option for late FF with impaired ventricular function. Protein dispersion improves with OHT, but PLE negatively affects the mid-term OHT outcome, mainly for early infective complications.