Contemporary Outcomes of the Fontan Operation: A Large Single-Institution Cohort

Comparison of definitive approaches for conotruncal defects following bidirectional Glenn procedure

BACKGROUND

Staged repair is common for complex conotruncal defects, often involving bidirectional Glenn (BDG) procedure. Following the cavopulmonary shunt, both Fontan completion and biventricular conversion (BiVC) serve as definitive approaches. The optimal strategy remains controversial.

METHODS

The baseline, perioperative and follow-up data were obtained for all paediatric patients with conotruncal defects who underwent BDG procedure as palliation in Fuwai Hospital from 2013 to 2022. Patients with single ventricle were excluded. The primary outcome was mortality. The secondary outcome was reintervention, including any cardiovascular surgeries and non-diagnostic catheterisations.

RESULTS

A total of 232 patients were included in the cohort, with 142 underwent Fontan (61.2%) and 90 underwent BiVC (38.8%). The median interstage period from BDG to the definitive procedure was 3.83 years (IQR: 2.72-5.42) in the overall cohort, 3.62 years (IQR: 2.57-5.15) in the Fontan group and 4.15 years (IQR: 3.05-6.13) in the BiVC group (p=0.03). The in-hospital outcomes favoured the Fontan group, including duration of cardiopulmonary bypass, aortic cross-clamp, mechanical ventilation and intensive care unit stay. Postoperative mortality was generally low and comparable, as was the reintervention rate (HR=1.42, 95% CI: 0.708 to 2.85, p=0.32). The left ventricular size was smaller at baseline and within the normal range at follow-up for both Fontan and BiVC groups; however, it was significantly larger with BiVC at follow-up.

CONCLUSION

In paediatric patients with conotruncal heart defects who underwent BDG procedure, BiVC is a feasible option, especially for patients with certain Fontan risk factors, and are not ideal candidates for successful Fontan completion.

Brady-arrhythmias requiring permanent pacemaker implantation during and after staged Fontan palliation

BACKGROUND

Brady-arrhythmia requiring pacemaker implantation remains one of the Fontan-specific complications before and after total cavopulmonary connection.

METHODS

A retrospective analysis of 620 patients who underwent total cavopulmonary connection between 1994 and 2021 was performed to evaluate the incidence of brady-arrhythmia and the outcomes after pacemaker implantation. Factors associated with the onset of brady-arrhythmia were identified.

RESULTS

A total of 52 patients presented with brady-arrhythmia and required pacemaker implantation. Diagnosis included 16 sinus node dysfunctions, 29 atrioventricular blocks, and 7 junctional escape rhythms. Pacemaker implantation was performed before total cavopulmonary connection (n = 16), concomitant with total cavopulmonary connection (n = 8), or after total cavopulmonary connection (n = 28, median 1.8 years post-operatively). Freedom from pacemaker implantation following total cavopulmonary connection at 10 years was 92%. Twelve patients needed revision of electrodes due to lead dysfunction (n = 9), infections (n = 2), or dislocation (n = 1). Lead energy thresholds were stable, and freedom from pacemaker lead revision at 10 years after total cavopulmonary connection was 78%. Congenitally corrected transposition of the great arteries (odds ratio: 6.6, confidence interval: 2.0-21.5, p = 0.002) was identified as a factor associated with pacemaker implantation before total cavopulmonary connection. Pacemaker rhythms for Fontan circulation were not a risk factor for survival (p = 0.226), protein-losing enteropathy/plastic bronchitis (p = 0.973), or thromboembolic complications (p = 0.424).

CONCLUSIONS

In our cohort of patients following total cavopulmonary connection, freedom from pacemaker implantation at 10 years was 92% and stable atrial and ventricular lead energy thresholds were observed. Congenitally corrected transposition of the great arteries was at increased risk for pacemaker implantation before total cavopulmonary connection. Having a pacemaker in the Fontan circulation had no adverse effect on survival, protein-losing enteropathy/plastic bronchitis, or thromboembolic complications.

Does the External Pericardial Lateral Tunnel Fontan Pathway Enlarge to Accommodate Somatic Growth? A Preliminary Analysis

Objectives: An ideal Fontan pathway should be capable of adapting to changes in circulatory demands. The external pericardial lateral tunnel Fontan (EPLTF) is constructed of viable, autologous tissue and may be capable of changing in size. We investigated the ability of the EPLTF to enlarge with increasing physiologic demands of somatic growth. Methods: Retrospective review of echocardiographic images for patients with a minimum of five years follow-up after EPLTF. Serial echocardiographic measurements of the EPLTF pathway were obtained at three distinct locations: the inferior vena cava junction with the EPLTF, midsection of the EPLTF, and cross-sectional area of the EPLTF visualized in a four-chamber view. Body surface area (BSA) was calculated at the time of each echocardiographic measurement. Changes in echocardiographic measurements over time were analyzed and compared with changes in BSA. Results: A total of 332 echocardiographic studies from 38 patients were reviewed. Significant enlargement of the EPLTF pathway is observed at the inferior vena caval junction (P < .001), midsection (P < .01), and cross-sectional area (P < .001). Repeated measures correlation between pathway measurements and BSA is highly significant (P < .001). Conclusions: The EPLTF pathway enlarges over time in correlation with increasing BSA. Further research is needed to define ideal pathway size, differentiate normal physiologic growth from pathologic enlargement, and correlate changes with clinical outcomes.

Impact of Optimal Fenestration Size on Outcomes of High-Risk Fontan Patients

BACKGROUND

We aimed to analyze mid-term outcomes of the fenestrated Fontan procedure, focusing on the fenestration size.

METHODS

We retrospectively reviewed the outcomes of the fenestrated Fontan procedure. Among 165 patients who underwent the Fontan procedure from 2011 to 2021, fenestration was created in 27 patients with the highest risks, including those with hypoplastic left heart syndrome, hypoplastic pulmonary arteries, heterotaxy syndrome with high pulmonary vascular resistance, and pulmonary arterial pressure >15 mm Hg. The patients underwent the procedure at a median age of three years (body weight, 11.4 kg; body surface area, 0.54 m2). Fenestration sizes were 3.5 to 5 mm.

RESULTS

Spontaneous fenestration closure occurred within one year postoperatively in nine patients. Among them, three experienced Fontan failure, necessitating refenestration. Although fenestration size did not differ, the size corrected by body surface area at the time of surgery was smaller in patients with fenestration closure (6.4 mm/m2 vs 8.3 mm/m2, P < .05). Patients with a fenestration <7 mm/m2 were more likely to have fenestration closure within one year postoperatively, and those with a fenestration >9 mm/m2 were more likely to have severe desaturation and require home oxygen therapy following discharge.

CONCLUSIONS

Spontaneous fenestration closure affected the frequency of Fontan complications. A very small fenestration size corrected by body surface area was a significant risk factor for spontaneous closure. Conversely, a very large fenestration size corrected by body surface area resulted in severe desaturation. The optimal fenestration size to prevent early spontaneous closure and severe desaturation is approximately 8 mm/m2.

Pre-Fontan Assessment Utilizing Combined Cardiac Catheterization and Cardiac MRI: Comparison to the Pre-Fontan Catheterization

Single ventricle patients eligible for Fontan completion undergo pre-Fontan catheterization for hemodynamic and anatomic assessment prior to surgery. Cardiac magnetic resonance imaging may be used to evaluate pre-Fontan anatomy, physiology, and collateral burden. We describe our center's outcomes in patients undergoing pre-Fontan catheterization combined with cardiac magnetic resonance imaging. A retrospective review of patients undergoing pre-Fontan catheterization from 10/2018 to 04/2022 at Texas Children's Hospital was performed. Patients were divided into 2 groups: combined cardiac magnetic resonance imaging and catheterization (combined group) and those who underwent catheterization only (catheterization only group). There were 37 patients in the combined group and 40 in the catheterization only group. Both groups were similar in age and weight. Patients undergoing combined procedures received less contrast, and experienced less in-lab time, fluoroscopy time and catheterization procedure time. Median radiation exposure was lower in the combined procedure group but was not statistically significant. Intubation and total anesthesia times were higher in the combined procedure group. Patients undergoing a combined procedure were less likely to have collateral occlusion performed than in the catheterization only group. Bypass time, intensive care unit length of stay, and chest tube duration were similar in both groups at the time of Fontan completion. Combined pre-Fontan assessment decreases catheterization procedure and fluoroscopy time associated with cardiac catheterization at the expense of longer anesthetic times, and results in similar Fontan outcomes compared to when cardiac catheterization alone is utilized.

Ventricular assist device support for failing Glenn circulation: Impact of concomitant Fontan completion in select patients

BACKGROUND

Ventricular assist device (VAD) support for failing Glenn circulation represents a unique challenge.

METHODS

We conducted a retrospective review of clinical outcomes in patients with VAD support for failing Glenn circulation between 2010 and 2020 at a tertiary pediatric institution.

RESULTS

Ten patients were included: INTERMACS profiles were 1 in 3 patients and 2 in 7 patients. The median age, weight, and body surface area were 3.2 years, 13.0 kg, and 0.5 m², respectively. Seven patients (70%) were implanted with continuous-flow devices and 3 with para-corporeal devices. Nine patients (90%) received heart transplant, with a median support duration of 77 days. Four (67%) out of 6 patients supported with discharge-capable devices were managed as outpatients. Post-transplant survival was 100%, with a median (range) follow up duration of 3.5 (1.8-11.9) years. There were 3 neurologic complications in 3 patients (0.9 events per patient-year); 2 intraoperative events (fatal hypoxia and symptomatic embolic stroke) and 1 postoperative (asymptomatic subarachnoid hemorrhage). Pump thrombosis occurred in one patient (0.3 events per patient-year), requiring pump exchange at day 65. Five patients (50%) received concomitant Fontan completion (fenestrated in 1). The Fontan-upgraded patients (vs Glenn) tended to be larger (median (range): 15.9 (12.6-22.9) vs 9.1 (7.7-22.8) kg), older (4.7 (3.1-6.5) vs 1.1 (0.9-10.1) years) and had a higher PaO₂/FiO₂ ratio (192 (52-336) vs 76 (59-78) mm Hg) on postoperative day 1.

CONCLUSION

Our experience suggests the feasibility of durable VAD support for failing Glenn circulation. Concomitant Fontan completion may be considered in select patients to improve oxygen delivery.

Pleural and mediastinal effusions after the extracardiac total cavopulmonary connection: Risk factors and impact on outcome

Background

This study investigated the volume and duration of pleural and mediastinal effusions following extracardiac total cavopulmonary connection, as well as preoperative risk factors and their impact on outcome.

Materials and methods

A total of 210 patients who underwent extracardiac total cavopulmonary connection at our center between 2012 and 2020 were included in this study. Postoperative daily amount of pleural and mediastinal drainage were collected and factors influencing duration and amount of effusions were analyzed. The impact of effusions on adverse events was analyzed.

Results

Median age at extracardiac total cavopulmonary connection was 2.2 (interquartile range, 1.8–2.7) years with median weight of 11.6 (10.7–13.0) kg. Overall duration of drainage after extracardiac total cavopulmonary connection was 9 (6–17) days. The total volume of mediastinal, right pleural, and left pleural drainage was 18.8 (11.9–36.7), 64.4 (27.4–125.9), and 13.6 (0.0–53.5) mL/kg, respectively. Hypoplastic left heart syndrome (p = 0.004) and end-diastolic pressure (p = 0.044) were associated with high volume of drainages, and hypoplastic left heart syndrome (p = 0.007), presence of aortopulmonary collaterals (p = 0.002), and high end-diastolic pressure (p = 0.023) were associated with long duration of drainages. Dextrocardia was associated with higher volume (p &lt; 0.001) and longer duration (p = 0.006) of left pleural drainage. Duration of drainage was associated with adverse events following extracardiac total cavopulmonary connection (p = 0.015).

Conclusion

Volume and duration of pleural and mediastinal effusions following extracardiac total cavopulmonary connection were related with hypoplastic left heart syndrome, aortopulmonary collaterals, and end-diastolic pressure. The duration of drainage for effusions was a risk factor for adverse events after total cavopulmonary connection.

Fontan circulation has improved life expectancy for infants born with complex heart disease over the last 50 years but has also resulted in significant morbidity

The prognosis for infants born with complex heart disease improved dramatically with the introduction of the Fontan circulation 50 years ago. With today's carefully designed and staged operations to a Fontan circulation, life expectancy has increased and most children will survive into adult life. The Fontan circulation entails an unphysiological circulation with high risk for multiple organ system dysfunction. Neurodevelopmental disabilities with adverse psychosocial effects are prevalent. The Fontan circulation may eventually fail and necessitate heart transplantation. CONCLUSION: Fifty years development of the Fontan circulation to today's staged surgical procedures has improved survival but also revealed the burden of a high morbidity for a growing number of patients.

Surgical outcomes of reoperation after Fontan completion

 

OBJECTIVES

Patients who have achieved Fontan circulation may require reoperation. We reviewed the outcomes of reoperation after Fontan completion and assessed the risk factors for poor outcomes.

METHODS

This was a retrospective study of 106 patients undergoing open-heart reoperations after Fontan completion in 2003 at a single institution.

RESULTS

The mean age at reoperation was 24.6 ± 8.3 years. A history of Fontan failure or end-organ dysfunction was noted in 30 patients. The reoperations included 73 total cavopulmonary connection conversions, 29 atrioventricular or semilunar valve operations (17 with total cavopulmonary connection conversions) and 4 other operations. Eight early deaths occurred. During a median follow-up of 5.5 (0.01–16.2) years, there were 3 late deaths and 9 second cardiac operations. The 10-year survival rate after reoperation was 89.8%, and the 5-year second cardiac operation-free survival was 84.3%. The 10-year survival rates were significantly lower in patients who underwent surgery before 2011 (75.8% vs 100%), had a history of Fontan failure or end-organ dysfunction (71.7% vs 97.3%), had preoperative central venous pressure >15 mmHg (64.9% vs 96.5%) and were operated on with deep hypothermic circulatory arrest (DHCA) (60.0% vs 91.3%). A history of Fontan failure or end-organ dysfunction, preoperative central venous pressure >15 mmHg and requirement of DHCA were identified as risk factors for mortality.

CONCLUSIONS

Reoperation after Fontan completion resulted in excellent mid-term outcomes. A history of failed Fontan circulation and the requirement of DHCA negatively affected survival outcomes.

Surgical Correction of Scoliosis in Children with Severe Congenital Heart Disease and Palliated Single Ventricle Physiology

STUDY DESIGN

Case series.

OBJECTIVE

In this study we focus on this group, and describe the largest cohort to date of single ventricle patients undergoing surgical correction of scoliosis at a single institution.

SUMMARY OF BACKGROUND DATA

Outcomes of spinal surgery for patients with congenital heart disease (CHD) have evolved and most affected patients have uncomplicated procedures. The risk of perioperative complications remains highest in patients with single ventricle ("Fontan") physiology.

METHODS

We reviewed patients with single ventricle CHD and operative scoliosis repair over a 25-year span. Patients who had undergone a Fontan, bidirectional Glenn, and/or Kawashima procedure before operative scoliosis repair were included. Patients were excluded if they lacked preoperative cardiac care and/or sufficient medical history at our institution.

RESULTS

Twenty-three patients were included. The average age at surgery was 13.6 years (range, 5-23). Seventy percent of the cohort was female (16/23). The majority of patients underwent a Fontan before scoliosis surgery (20/23, 87%). Patients without intraoperative tranexamic acid (TXA) had a 67% complication rate (8/12) versus 36% (4/11) in those with intraoperative TXA (P = 0.29). There was a significant difference in estimated blood loss by weight (cc/kg) between non-TXA and TXA patients (P = 0.016). Twelve patients experienced complications (52%), all of which occurred postoperatively. There were no deaths, cerebrovascular events, adverse perioperative cardiac or hemodynamic complications, or wound infections. Using the Clavien-Dindo-Sink classification for postoperative complications, four patients had serious adverse events, including one permanent neurologic deficit.

CONCLUSION

Spinal surgery for scoliosis has been performed in selected patients with single ventricle physiology at a single institution without mortality for 25 years. Operative blood loss may be reduced by routine use of TXA. Complications occur most commonly in the postoperative period, and can include pleural effusion.Level of Evidence: 4.

One and One-Half Ventricle Repair: Role for Restricting Antegrade Pulmonary Blood Flow

BACKGROUND

In patients with hypoplastic subpulmonary ventricles, the one and one-half ventricle (1.5V) repair is an alternative to the Fontan procedure. However, in 1.5V-treated patients with pulsatile pulmonary blood flow, superior vena cava (SVC) hypertension or right atrial hypertension may develop. This study aimed to (1) describe patient outcomes after 1.5V repair and (2) determine whether pulmonary artery septation at 1.5V repair confers a lower risk of SVC or right atrial hypertension.

METHODS

This study retrospectively reviewed patients who underwent a 1.5V repair between 1989 and 2020. The primary outcome was transplant-free survival. Secondary outcomes were postoperative SVC hypertension (defined by mean Glenn pressures greater than 17 mm Hg, SVC flow reversal or pulsatility, venovenous collateral vessels, or SVC syndrome) and right atrial hypertension (defined as mean right atrial pressures greater than 10 mm Hg with inferior vena cava and hepatic vein dilation or flow reversal).

RESULTS

A total of 74 patients underwent 1.5V repair at a median age of 29.6 months (interquartile range, 8.9 to 45.5 months). Median follow-up time was 39.9 months (interquartile range, 11.4 to 178.1 months). Transplant-free survival at 10 years was 92.4%. Among survivors, 12% (8 of 69) had right atrial hypertension and 39% (27 of 69) had SVC hypertension on follow-up. Survivors with unseptated pulmonary arteries had a greater risk of SVC hypertension compared with patients with septated pulmonary arteries (44% vs 10%; P = .04). No difference was found in right atrial hypertension between the 2 groups.

CONCLUSIONS

Patients with 1.5V repair avoid Fontan-associated complications with favorable transplant-free survival. However, SVC hypertension remains a significant long-term complication. Pulmonary artery septation at 1.5V repair may reduce the risk of SVC hypertension.

Relationship of Ventricular Morphology and Atrioventricular Valve Function to Long-Term Outcomes Following Fontan Procedures

BACKGROUND

The influence of ventricular morphology on Fontan outcomes is controversial.

OBJECTIVES

This study hypothesized that dysfunction of the single right ventricle (RV) and right atrioventricular valve regurgitation (AVVR) increases over time and adversely impacts late outcomes following a Fontan operation. A single-center retrospective study was performed.

METHODS

From 1985 through 2018, 1,162 patients underwent the Fontan procedure at our center and were included in this study. Transplant and takedown free survival, ventricular, and atrioventricular valve dysfunction after Fontan were analyzed. Death or heart transplantation information was obtained from the National Death Index and the Scientific Registry of Transplant Recipients.

RESULTS

The follow-up rate was 99%. Morphologic RV was present in 58% of patients. Transplant and takedown free survival were 91%, 75%, and 71% at 10 years, 20 years, and 25 years, respectively. Morphologic RV was an independent risk factor for transplant, takedown free survival (hazard ratio: 2.4; p = 0.008). The AVVR, which preceded ventricular dysfunction in most cases, was associated with the development of ventricular dysfunction after Fontan (odds ratio: 4.3; 95% confidence interval: 2.7 to 6.7; p < 0.001). Furthermore, AVVR and ventricular dysfunction progressed over time after Fontan, especially in the RV (AVVR: p < 0.0001, ventricular dysfunction: p < 0.0001).

CONCLUSIONS

Morphologic RV is negatively associated with the long-term survival following the Fontan, possibly due to a tendency toward progressive AVVR and deterioration of the single ventricle function. Additional volume overload caused by AVVR may be one of the main factors accelerating the dysfunction of the single RV, implying that early valve intervention may be warranted.

Long-term Outcomes of Extracardiac Total Cavopulmonary Connection for Apicocaval Juxtaposition

BACKGROUND

The long-term outcomes of a total cavopulmonary connection (TCPC) with an extracardiac conduit (ECC) for patients with apicocaval juxtaposition (ACJ) remain unclear.

METHODS

A total of 38 patients with ACJ who underwent TCPC with ECC between 1998 and 2014 were enrolled in this study. For 19 patients with a superior vena cava - inferior vena cava contralateral position, a long-curved route rounding the opposite side of the apex was selected (CC group). For 11 patients with a superior vena cava-inferior vena cava ipsilateral position, a long-curved route was principally selected (IC group); however, a short, straight route was selected for 8 patients because there was sufficient space behind the ventricular apex (IS group).

RESULTS

Follow-up was completed in all patients, with a mean follow-up duration of 13.2 ± 4.9 years. The angles of the caudal conduit anastomosis site measured from the frontal view of cineangiography had significantly straightened in the CC group from 1 year to 15 years (P < .05) and in the IC group from 1 year to 10 years (P < .05). There were 2 late mortalities and 6 reoperations during follow-up. Overall survival and freedom from reoperation rates at 15 years were 95% and 82%, respectively. There were no conduit-related or route-related complications such as death, reoperations, pulmonary venous obstructions, conduit obstructions, or pulmonary arteriovenous malformations in any of the groups.

CONCLUSIONS

Even though chronologic geometric changes of curved ECCs were observed, TCPC with ECC for patients with ACJ can be safely applied without conduit- or route-related complications in long-term follow-up.

Biventricular Conversion in Unseptatable Hearts: "Ventricular Switch"

Patients with complex systemic and pulmonary venous anatomy, common atrioventricular canal defects and conotruncal anomalies have traditionally been routed to univentricular palliation and labeled as "unseptatable." This report describes our initial experience in septation/biventricular conversion ("ventricular switch"), utilizing the left ventricle (LV) as the subpulmonary ventricle, essentially recapitulating the physiology of congenitally corrected transposition of the great arteries. Five consecutive patients with challenging anatomic configuration underwent septation. All patients were severely cyanotic and had important functional limitations. All patients required complex atrial septation. Ventricular septation was precluded by fixed pulmonary vascular resistance in 2 patients. Systemic venous return was diverted to the morphologic LV as part of physiological 2V (n = 4) or 1.5 V repair (n = 1). Median conversion age was 9 years (range 11 months-46 years). Four patients had 12 previous cardiac surgical procedures in preparation for univentricular repair elsewhere. Three dimensional-printed heart models evaluated feasibility of septation. All patients are alive at a median follow-up of 0.6 years (range 0.08-2.7 years). Median hospital stay was 13 (range 10-60) days. LV recruitment improved functional status and significantly increased systemic oxygen saturation in all patients (79 ± 7% vs 95 ± 5%, P = 0.003). We report a novel paradigm for successfully utilizing both ventricles with the morphologic LV as the subpulmonary ventricle, in a complex population thought to be unseptatable. This approach is versatile and can likely be extrapolated to other complex anatomic configurations. Although we utilized this strategy in patients of variable age, earlier ventricular switch may yield the best results.

Salvage of an epicardial lead in a pacemaker-dependent patient with Fontan palliation using an IS-1 extender

We present a case report of severed epicardial atrial lead salvage using an IS-1 lead extender. A 37-year-old male with single ventricle physiology, Fontan palliation, sinus node dysfunction, recurrent atrial tachycardias, and atrial fibrillation resulting in failing Fontan physiology presented with failure of the atrial pacing lead. The patient was initially paced with an epicardial system that had to be removed due to pocket infection, and the epicardial leads were cut and abandoned. Given his significant sinus node dysfunction he required atrial pacing to allow for rhythm control. The failing Fontan physiology of the patient precluded him from undergoing surgery for epicardial lead placement or a complex intravascular lead placement procedure (although anatomically feasible). We considered the option of salvaging the existing epicardial atrial leads to provide atrial pacing, allowing for rhythm control and improvement of his failing Fontan physiology as a bridge to a more permanent pacing solution. This case report is important because it demonstrates how a lead extender can be used to salvage a severed pacemaker lead. This may be useful for patients in whom implantation of new leads is not promptly feasible due to patient anatomy and/or clinical status.