Prevalence of atrial tachyarrhythmia in adults after Fontan operation

Long-Term Outcomes and Predictors of Recurrence in Atrial Arrhythmia Ablations Post-Fontan Procedure: A Retrospective Analysis

Background

Supraventricular tachycardia (SVT) is common in patients who have undergone a Fontan procedure and is poorly tolerated. SVT recurrence rates after catheter ablations are high. Recent data on the outcomes of SVT ablation and the predictors of recurrence in this population are limited.

Methods

Electronic medical records of patients who had undergone a Fontan procedure and SVT ablation between January 1, 1995, and October 1, 2023, at a tertiary care center were reviewed. Demographic, clinical, and outcome variables over 5 years were compared between patients with and without SVT recurrence.

Results

Twenty-five patients (56% male, mean age 31.5 ± 7.2 years) with a mean age of 6.1 ± 3.6 years at Fontan surgery were included. Ablation success rate was 92%. Recurrence occurred in 12 (48%) patients, of whom 7 (28%) required repeat ablations. Thirteen (59%) patients had a cardiac hospitalization, and one patient died in the 5-year follow-up period. Atypical (71%) and typical (33%) right atrial flutter were the most common SVTs. Higher brain natriuretic peptide (BNP) levels pre- (1,702 vs. 242, P = 0.028) and post-ablation (862 vs. 112, P = 0.017) were associated with recurrence. Atriopulmonary (AP) Fontan type (91% vs. 17%, P = 0.0006), number of radiofrequency (RF) applications (48 vs. 14, P = 0.045), post-ablation cardiovascular (CV) hospitalizations (82% vs. 36% P = 0.030), and post-ablation antiarrhythmic prescriptions (1.8 vs. 1.2, P = 0.0256) were more prevalent in patients with recurrence.

Conclusion

Catheter ablation of SVT in patients with Fontan physiology is associated with a high success rate and a high long-term recurrence rate. Recurrence of SVT is associated with markers of severe heart disease and type of Fontan.

Atrial Fibrillation in Heart Failure Due to Congenial Heart Disease

Atrial arrhythmia is the most common complication in the adult congenital heart disease population, and with an aging population, atrial fibrillation is rapidly increasing in prevalence-particularly in those with concomitant heart failure. There is much to be determined regarding the pathophysiology of atrial fibrillation in the adult congenital heart disease population, but it is likely linked to the congenital heart defects, shunts, surgical patches, and coexisting hemodynamic lesions associated with the congenital heart disease process and physiology. This review focuses on the management of atrial fibrillation and heart failure in patients with adult congenital heart disease.

Review of rhythm disturbances in patient after fontan completion: epidemiology, management, and surveillance

Purpose

The Fontan operation is commonly associated with alterations in heart rhythms, both tachycardic and bradycardic. Despite modifications to attempt to mitigate these complications, arrythmias still frequently occur. The purpose of this review is to examine the literature regarding the scope of the problem, therapeutic options, and current recommendations regarding screening and surveillance.

Recent findings

Modifications to the original Fontan procedure, antiarrhythmic medications, and improvements in catheter ablation procedures have improved the management of patients with arrhythmias following Fontan palliation. There is growing interest in the role of junctional rhythm in the role of Fontan dysfunction. While chronotropic incompetence has often been blamed for poor exercise testing, there is evidence that decreased performance may be related to ventricular filling and Fontan hemodynamics.

Summary

Tachyarrhythmias are an important cause of mortality and morbidity after the Fontan operation. Prompt and aggressive management of arrhythmias with the goal of maintaining sinus rhythm is vital. Management strategies such as anti-arrhythmic medications, ablation, anti-tachycardia pacing and Fontan conversion should be seen as complementary and used early to prevent hemodynamic deterioration. Bradyarrythmias likely also contribute to Fontan failure. Pacing is the primary management strategy with evidence supporting use of atrial pacing. However, ventricular pacing seems to often lead to deleterious effects. Current guidelines recommend surveillance with Holter monitor every 2-3 years in adolescents and every 1-2 years in adults. Future directions for research include further assessment of junctional rhythm and its management as well as further identifying patients in which pacing would be beneficial.

Long-Term Outcomes of Fontan Patients With an Extracardiac Conduit: A Systematic Review and Meta-Analysis

BACKGROUND

Although Fontan palliation improves survival, it poses a large burden of lifelong morbidity. In extracardiac Fontan (ECF) patients, for example, conduit stenosis developing over time has been associated with Fontan failure and other adverse outcomes. This systematic review, for the first time, synthesized existing data on various long-term outcomes of ECF patients, including change in conduit and associated outcomes.

METHODS

We searched the Medline, Embase, and Cochrane indexes from inception to 2023 and included studies reporting separate results for ECF patients with a follow-up time of at least 3 years. Full-text studies were assessed for risk of bias. We summarised information on the study, patient characteristics, and outcomes narratively and with the use of descriptive tables. Meta-analysis was performed to calculate pooled incidence rates of adverse events.

RESULTS

We included 61 full-text studies, with most studies published after 2009 (77.0%) and using a retrospective cohort design (76.2%). The pooled incidence rates per 100 person-years were for arrhythmia 1.8 (95% confidence interval [CI] 1.3-2.6), thrombotic events 0.2 (95% CI 0.1-0.4), protein-losing enteropathy 0.7 (95% CI 0.5-1.0), conduit obstruction 0.7 (95% CI 0.3-1.5), reoperation 1.9 (95% CI 1.1-3.4), and late death 0.3 (95% CI 0.2-0.5). The ranges of hemodynamic and exercise parameters and findings from studies reporting changes in conduit size and liver disease were reported.

CONCLUSIONS

Although many studies have largely focused on long-term survival, several other adverse outcomes require further research to develop consensus-based definitions and approaches for evaluations, especially as the ECF population ages. (PROSPERO: CRD42024533080).

Mountains and Waves: Fontan Circulation in Different Environmental Conditions

As surgical options and medical care for patients with univentricular heart physiology continue to improve, leading to increased life expectancy and quality of life, a new population of Fontan patients is growing up with the desire to participate in leisure activities, including aquatic activities, high-altitude stays, and air travel. Due to significant data gaps and insufficient experience, current guidelines do not provide clear recommendations, leading to uncertainty and sometimes restrictive patient management. This review summarizes new insights and the current state of research on this subject and provides an overview of the long overdue change in policies toward less restrictive counseling for Fontan patients regarding swimming, diving, high-altitude stays, and air travel. The current review summarizes the physiologic impact of aquatic and high-altitude activities on the cardiovascular system and presents currently available data on this topic in Fontan patients. Patients with Fontan circulation in good clinical shape can tolerate activities in the water and in the mountains as well as air traveling without critical events. In order to be able to make general recommendations, further studies with larger numbers of cases must be carried out.

Late development of intra-atrial reentrant tachycardia in lateral tunnel Fontan patients and the preventive role of prophylactic cryoablation

OBJECTIVE

Intra-atrial reentrant tachycardia is an important late-onset complication in patients undergoing the Fontan procedure. However, the protective effects of prophylactic cryoablation against late-onset intra-atrial reentrant tachycardia are unclear. This study investigated the late development of intra-atrial reentrant tachycardia in patients undergoing the lateral tunnel Fontan procedure and the role of prophylactic cryoablation.

METHODS

This was a single-center retrospective cohort study of patients who underwent the lateral tunnel Fontan procedure between 1988 and 2003. Univariate and multivariable competing risks regression models were used to determine the associations of prophylactic cryoablation and covariates with the outcomes of interest: late-onset intra-atrial reentrant tachycardia, all-cause mortality, and cardiovascular mortality.

RESULTS

In total, 130 patients who underwent the lateral tunnel Fontan procedure, 30 of whom had undergone prophylactic cryoablation, were included in this study and followed up for a median of 23.6 years (interquartile range, 17.7-26.5). Intra-atrial reentrant tachycardia was identified in 14 patients (10.8%), none of whom underwent prophylactic cryoablation. The median Fontan-to-intra-atrial reentrant tachycardia time was 17.2 years (interquartile range, 11.1-23.1). Prophylactic cryoablation was protective against late-onset intra-atrial reentrant tachycardia (P < .0001) and cardiovascular mortality (P < .0001) in the type 3 test.

CONCLUSIONS

None of the patients who underwent prophylactic cryoablation developed late-onset intra-atrial reentrant tachycardia during a median follow-up time of 22.9 years. Our study demonstrated that prophylactic cryoablation was effective in preventing late-onset intra-atrial reentrant tachycardia and cardiovascular mortality in patients undergoing the lateral tunnel Fontan.

Long-term incidence of arrhythmias in extracardiac conduit Fontan and comparison between systemic left and right ventricle

AIMS

The extracardiac conduit-Fontan (ECC) has become the preferred technique for univentricular heart palliation, but there are currently no data on the incidence of long-term arrhythmias. This study investigated the incidence of arrhythmias and relation to single ventricle morphology in the long-term follow-up (FU) in ECC.

METHODS AND RESULTS

All patients with ECC performed in our Centre between 1987 and 2017 were included (minimum FU 5 years). Of 353 consecutive patients, 303 [57.8% males, aging 8-50 (median 20) years at last FU] were considered and divided into two groups depending on left (194 in Group 1) or right (109 in Group 2) ventricular morphology. Eighty-five (28%) experienced ≥1 arrhythmic complications, with early and late arrhythmias in 17 (5.6%) and 73 (24.1%) patients, respectively. Notably, late bradyarrhythmias occurred after 6 years in 21 (11%) patients in Group 1, and in 15 (13.8%) in Group 2 [P = 0.48]. Late tachyarrhythmias occurred in 55 (18.2%) patients after 12 years: 33 (17%) in Group 1 and 22 (20.2%) patients in Group 2 [P  = 0.5]. Ventricular tachycardias (VT) were documented after 12.5 years in 14 (7.2%) patients of Group 1 and 15 (13.8%) of Group 2 [P = 0.06] with a higher incidence in Group 2 during the FU [P = 0.005].

CONCLUSION

Extracardiac conduit is related to a significant arrhythmic risk in the long-term FU, higher than previously reported. Bradyarrhythmias occur earlier but are less frequent than tachyarrhythmias. Interestingly, patients with systemic right ventricle have a significantly higher incidence of VT, especially in a very long FU.

Tachyarrhythmia after the total cavopulmonary connection: incidence, prognosis, and risk factors

OBJECTIVE

The purpose of this study is to evaluate the incidence and outcomes regarding tachyarrhythmia in patients after total cavopulmonary connection.

METHODS

A retrospective analysis of 620 patients who underwent total cavopulmonary connection between 1994 and 2021 at our institution was performed. Incidence of tachyarrhythmia was depicted, and results after onset of tachyarrhythmia were evaluated. Factors associated with the onset of tachyarrhythmia were identified.

RESULTS

A total of 52 (8%) patients presented with tachyarrhythmia that required medical therapy. Onset during hospital stay was observed in 27 patients, and onset after hospital discharge was observed in 32 patients. Freedom from late tachyarrhythmia following total cavopulmonary connection at 5, 10, and 15 years was 97, 95, and 91%, respectively. The most prevalent late tachyarrhythmia was atrial flutter (50%), followed by supraventricular tachycardia (25%) and ventricular tachycardia (25%). Direct current cardioversion was required in 12 patients, and 7 patients underwent electrophysiological study. Freedom from Fontan circulatory failure after onset of tachyarrhythmia at 10 and 15 years was 78% and 49%, respectively. Freedom from occurrence of decreased ventricular systolic function after the onset of tachyarrhythmia at 5 years was 85%. Independent factors associated with late tachyarrhythmia were dominant right ventricle (hazard ratio, 2.52, p = 0.02) and weight at total cavopulmonary connection (hazard ratio, 1.03 per kilogram; p = 0.04). Type of total cavopulmonary connection at total cavopulmonary connection was not identified as risk.

CONCLUSIONS

In our large cohort of 620 patients following total cavopulmonary connection, the incidence of late tachyarrhythmia was low. Patients with dominant right ventricle and late total cavopulmonary connection were at increased risk for late tachyarrhythmia following total cavopulmonary connection.

Atrial Fibrillation Ablation in Congenital Heart Disease: Therapeutic Challenges and Future Perspectives

The increasing prevalence of atrial fibrillation (AF) in adults with congenital heart disease raises significant questions regarding its management. The unique underlying anatomic and physiological background further adds to the difficulty in eliminating the AF burden in these patients. Herein, we provide an overview of the current knowledge on the pathophysiology and risk factors for AF in adult congenital heart disease, with a special focus on the existing challenges in AF ablation. Emerging imaging modalities and ablation techniques might have a role to play. Evidence regarding the safety and efficacy of AF ablation in adult congenital heart disease is summarized, especially for patients with an atrial septal defect, Ebstein anomaly of the tricuspid valve, tetralogy of Fallot, and Fontan circulation. Finally, any remaining gaps in knowledge and potential areas of future research are highlighted.

Atrial and Ventricular Arrhythmia in Adults With Shone Complex: A Single-Center Cohort Study

Background

Multilevel obstruction in left ventricular inflow and outflow predisposes to arrhythmias in Shone's complex (SC).

Objectives

The purpose of this study was to study the prevalence and outcomes (heart failure [HF] hospitalization, cardiac transplant, death) of cardiac arrhythmias in adults with SC.

Methods

Adults with SC (defined as ≥2 lesions out of supramitral ring, parachute mitral valve, subvalvular/valvular aortic stenosis (AS), and aortic coarctation) seen at Mayo Clinic between January 1999 and March 2020 were identified and evaluated for the presence of sustained atrial fibrillation, atrial flutter, and ventricular arrhythmias (VA). Kaplan-Meier survival analysis was used to calculate the occurrence of these arrhythmias.

Results

Seventy-three patients with SC (mean age at first visit 33 ± 13 years) were identified. Most common anomalies were valvular AS (88%), coarctation (85%), parachute mitral valve (44%), subvalvular AS (44%), and supramitral ring (25%). Atrial arrhythmias were diagnosed in 24 patients (33%) at a mean age of 34.6 ± 12.7 years. Patients with atrial fibrillation and atrial flutter had higher number of surgeries, left atrial size, right ventricular systolic pressure, and HF hospitalizations. A rhythm control approach was used in majority of patients (75% on antiarrhythmic drugs and 50% underwent catheter ablation). Sustained VA occurred in 6 of 73 patients of whom 4 had an ejection fraction <40%. Death and cardiac transplantation occurred in 11 and 3 patients, respectively, during a median follow-up of 7.3 ± 6.0 years.

Conclusions

In adults with SC, atrial arrhythmias occurred in one-third of patients, were associated with more HF hospitalizations, and frequently required rhythm control. Prevalence of sustained VA was 8% and implantable cardioverter-defibrillator implantation should be considered in those with reduced ejection fraction.

Combined and intraoperative risk modelling for oesophagectomy: A systematic review

BACKGROUND

Oesophageal cancer is the eighth most common malignancy worldwide and is associated with a poor prognosis. Oesophagectomy remains the best prospect for a cure if diagnosed in the early disease stages. However, the procedure is associated with significant morbidity and mortality and is undertaken only after careful consideration. Appropriate patient selection, counselling and resource allocation is essential. Numerous risk models have been devised to guide surgeons in making these decisions.

AIM

To evaluate which multivariate risk models, using intraoperative information with or without preoperative information, best predict perioperative oesophagectomy outcomes.

METHODS

A systematic review of the MEDLINE, EMBASE and Cochrane databases was undertaken from 2000-2020. The search terms used were [(Oesophagectomy) AND (Model OR Predict OR Risk OR score) AND (Mortality OR morbidity OR complications OR outcomes OR anastomotic leak OR length of stay)]. Articles were included if they assessed multivariate based tools incorporating preoperative and intraoperative variables to forecast patient outcomes after oesophagectomy. Articles were excluded if they only required preoperative or any post-operative data. Studies appraising univariate risk predictors such as preoperative sarcopenia, cardiopulmonary fitness and American Society of Anesthesiologists score were also excluded. The review was conducted following the preferred reporting items for systematic reviews and meta-analyses model. All captured risk models were appraised for clinical credibility, methodological quality, performance, validation and clinical effectiveness.

RESULTS

Twenty published studies were identified which examined eleven multivariate risk models. Eight of these combined preoperative and intraoperative data and the remaining three used only intraoperative values. Only two risk models were identified as promising in predicting mortality, namely the Portsmouth physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM) and POSSUM scores. A further two studies, the intraoperative factors and Esophagectomy surgical Apgar score based nomograms, adequately forecasted major morbidity. The latter two models are yet to have external validation and none have been tested for clinical effectiveness.

CONCLUSION

Despite the presence of some promising models in forecasting perioperative oesophagectomy outcomes, there is more research required to externally validate these models and demonstrate clinical benefit with the adoption of these models guiding postoperative care and allocating resources.

SCUBA Diving in Adult Congenital Heart Disease

Conventionally, scuba diving has been discouraged for adult patients with congenital heart disease (ACHD). This restrictive sports advice is based on expert opinion in the absence of high-quality diving-specific studies. However, as survival and quality of life in congenital heart disease (CHD) patients have dramatically improved in the last decades, a critical appraisal whether such restrictive sports advice is still applicable is warranted. In this review, the cardiovascular effects of diving are described and a framework for the work-up for ACHD patients wishing to engage in scuba diving is provided. In addition, diving recommendations for specific CHD diagnostic groups are proposed.

Atrial Flutters in Adults with Congenital Heart Disease

The macroreentrant atrial tachycardia is very frequent in the adults with congenital heart disease. The impact of the arrhythmias on this type of patients is related to several factors: the anatomy and physiopathology of the specific congenital heart disease (CHD), the sequelae of the corrective surgery or surgical palliation, the presence of residual lesions (shunt, regurgitation), and the age and the clinical status of the patient and the comorbidities. In turn, the mechanism of the MAT depends on the peculiar features of the conduction's system in the CHD and native and acquired (post-surgery) substrates.

Thromboembolic characteristics and role of anticoagulation in long-standing Fontan circulation

Introduction

The risk of thromboembolism increases with duration of Fontan circulation. Preventive drug strategies are still discussed controversially. We aimed to characterize clinical relevant thromboembolism in long-standing Fontan circulation and to analyse the protective effect of Acetylsalicylic acid (ASA) and Vitamin K Antagonists (VKA).

Method

78 patients (age ≥16 years) were included (mean age 20.7 ± 5.7 years; 51 male). Last medication and duration of therapy were documented. Perioperative events were excluded. Mean time of Fontan circulation was 21.1 ± 6.3 years, mean observation time 8.1 ± 5.6 years.

Results

44 patients were on VKA, 15 on ASA, 19 without treatment. Fifteen (19.2%) patients experienced thromboembolism. Nine patients had deep venous thromboses, among these five experienced pulmonary embolism. Four patients presented with supraventricular tachycardia (SVT), two with cerebral embolism and thrombus within the Fontan tunnel respectively. Two patients had an isolated thrombus in the Fontan tunnel. Time of Fontan circulation was significantly longer in thromboembolism (25.6 ± 8.3 years vs. 20.0 ± 5.2 years, p < 0.001). NYHA-class was worse (p = 0.03). Lacking treatment [OR 10.2 (95%CI 1.5-66.3)] and ASA [OR 1.25(95%CI)1.06-1.22] carried significantly higher risk of thromboembolism than VKA [OR 0.17 (95%CI 0.09-0.33)]. Kaplan-Meier analysis did n't differ in lacking treatment versus ASA (p = 0.2). VKA showed the best net-benefit regarding thromboembolism/bleeding complications (VKA: 11.4%, ASA 25%, VKA vs. lacking treatment 63.2%: p < 0.001).

Conclusion

In long-standing Fontan circulation anticoagulation appears to be a safe treatment option to prevent late thromboembolism mainly caused by deep vein thrombosis and intracardiac thrombus formation associated with SVT.

Catheter ablation of atrial arrhythmias in patients post-Fontan

Atrial arrhythmias are highly prevalent in the aging Fontan population and contribute importantly to morbidity and mortality. Although the most common arrhythmia is scar-based intra-atrial re-entrant tachycardia, various other arrhythmias may occur including focal atrial tachycardia, atrioventricular node-dependent tachycardias, and atrial fibrillation. The type and prevalence of atrial arrhythmia is determined, in part, by the underlying congenital defect and variant of Fontan surgery. While the cumulative incidence of atrial tachyarrhythmias has decreased substantially from the atriopulmonary anastomosis to the more recent total cavopulmonary connection Fontan, the burden of atrial arrhythmias remains substantial. Management is often multi-faceted and can include anticoagulation, anti-arrhythmic drug therapy, pacing, and cardioversion. Catheter ablation plays a key role in arrhythmia control. Risks and benefits must be carefully weighed. Among the important considerations are the clinical burden of arrhythmia, ventricular function, hemodynamic stability in tachycardia, suspected arrhythmia mechanisms, risks associated with anaesthesia, venous access, approaches to reaching the pulmonary venous atrium, and accompanying co-morbidities. Careful review of surgical notes, electrocardiographic tracings, and advanced imaging is paramount, with particular attention to anatomic abnormalities such as venous obstructions and displaced conduction systems. Despite numerous challenges, ablation of atrial arrhythmias is effective in improving clinical status. Nevertheless, onset of new arrhythmias is common during long-term follow-up. Advanced technologies such as high-density mapping catheters and remote magnetic guided ablation carry the potential to further improve outcomes. Fontan patients with atrial arrhythmias should be referred to centers with dedicated expertise in congenital heart disease including catheter ablation, anaesthesia support, and advanced imaging.

Current Treatment Options for the Failing Fontan Circulation

The Fontan operation was introduced in 1968. For congenital malformations, where biventricular repair is unsuitable, the Fontan procedure has provided a long-term palliation strategy with improved outcomes compared to the initially developed procedures. Despite these improvements, several complications merely due to a failing Fontan circulation, including myocardial dysfunction, arrhythmias, increased pulmonary vascular resistance, protein-losing enteropathy, hepatic dysfunction, plastic bronchitis, and thrombo-embolism, may occur, thereby limiting the life-expectancy in this patient cohort. This review provides an overview of the most common complications of Fontan circulation and the currently available treatment options.

Long-term management of Fontan patients: The importance of a multidisciplinary approach

The Fontan operation is a palliative procedure that leads to increased survival of patients with a functional single ventricle (SV). Starting from 1967 when the first operation was performed by Francis Fontan, more and more patients have reached adulthood. Furthermore, it is expected that in the next 20 years, the population with Fontan circulation will reach 150,000 subjects. The absence of right ventricular propulsion and the inability to improve cardiac output because of the low cardiac reserve are the main issues with the Fontan circulation; however, potential complications may also involve multiple organ systems, such as the liver, lungs, brain, bones, and the lymphatic system. As these patients were initially managed mainly by pediatric cardiologists, it was important to assure the appropriate transition to adult care with the involvement of a multidisciplinary team, including adult congenital cardiologists and multiple subspecialists, many of whom are neither yet familiar with the pathophysiology nor the end-organ consequences of the Fontan circulation. Therefore, the aim of our work was to collect all the best available evidence on Fontan's complications management to provide "simple and immediate" information sources for practitioners looking for state of the art evidence to guide their decision-making and work practices. Moreover, we suggest a model of follow-up of patients with Fontan based on a patient-centered multidisciplinary approach.

Fontan-Associated Liver Disease: Pathophysiology, Staging, and Management

Fontan-associated liver disease is the term used to encompass the disorders arising from abnormal hemodynamic alterations and systemic venous congestion after the Fontan procedure. The histological changes produced in the liver are similar but not equivalent to those seen in other forms of cardiac liver disease. While the natural history of this form of liver disease is poorly established, many Fontan patients ultimately develop portal hypertension-related complications such as ascites, esophageal varices, malnutrition, and encephalopathy. Fontan survivors also show an elevated risk of hepatocellular carcinoma. Adequate staging of the liver damage is essential to anticipate screening strategies and improve global management.

Utility of Surveillance Ambulatory Rhythm Monitoring in the Pediatric Fontan Population

Our institution established a Fontan surveillance plan, which included ambulatory rhythm monitoring (ARM) at 6, 10, 13, 16 and 19 years old, for early detection of Fontan-associated complications. We conducted a retrospective chart review of Fontan patients followed at our institution 2014-2018 to determine the utility of surveillance ARMs. 139 ARMs from 83 patients were included. ARMs with supraventricular tachycardia, sinus node dysfunction, accelerated junctional rhythm, > 1st degree atrioventricular block, and complex ventricular ectopy were classified as positive for arrhythmia. Arrhythmias were occult if detected on surveillance ARM. The ARM indication was surveillance in 78 (56%) and clinically indicated in 61 (44%). 52 (37%) ARMs in 27 (33%) patients had an arrhythmia. There was no difference in the age of patients with and without arrhythmias [median 10.9 (6.5, 17.1 years) vs. 8.8 (7, 13.6 years), p = 0.5]. Clinically indicated ARMs more frequently demonstrated arrhythmias than surveillance ARMs (52% vs. 26%, p < 0.01). Compared to patients without arrhythmias, those with arrhythmias were more likely to be female (48% vs. 23%, p = 0.02), have a single right ventricle (46% vs. 19%, p < 0.01) and longer QRS duration on ECG [100 (91, 116 ms) vs. 94 (84, 104 ms), p = 0.046]. Patients with occult arrhythmias were less likely to have moderate to severe atrioventricular valvar regurgitation (0% vs. 46%; p = 0.04) or ventricular dysfunction (0% vs. 46%; p = 0.04) than those with clinical arrhythmia(s). Arrhythmia findings resulted in change in management for 16/52 (31%) ARMs. The findings suggest the frequent presence of arrhythmias on periodic ARMs in patients following the Fontan procedure regardless of symptomatic status.

A 45-year experience with the Fontan procedure: tachyarrhythmia, an important sign for adverse outcome

OBJECTIVES

This study aims to evaluate our 45-year experience with the Fontan procedure and to identify risk factors for late mortality and morbidity.

METHODS

Demographic, preoperative, perioperative and postoperative characteristics were retrospectively collected for all patients who underwent a Fontan procedure in a single centre between 1972 and 2016.

RESULTS

The study included 277 Fontan procedures (44 atriopulmonary connections, 28 Fontan-Björk, 42 lateral tunnels and 163 extracardiac conduits). Early failure occurred in 17 patients (6.1%). Median follow-up of the study cohort was 11.9 years (Q1-Q3 7.6-17.5). Longest survival estimates were 31% [95% confidence intervals (CI) 18-44%] at 35 years for atriopulmonary connection/Björk, 87% (95% CI 63-96%) at 20 years for lateral tunnel and 99% (95% CI 96-100%) at 15 years for extracardiac conduit. Estimated freedom from Fontan failure (death, heart transplant, take-down, protein-losing enteropathy, New York Heart Association III-IV) at 15 years was 65% (95% CI 52-76%) for atriopulmonary connection/Björk, 90% (95% CI 73-97%) for lateral tunnel and 90% (95% CI 82-94%) for extracardiac conduit. The development of tachyarrhythmia was an important predictor of Fontan failure [hazard ratio (HR) 2.6, 95% CI 1.2-5.8; P = 0.017], thromboembolic/neurological events (HR 3.6, 95% CI 1.4-9.4; P = 0.008) and pacemaker for sinus node dysfunction (HR 3.7, 95% CI 1.4-9.6; P = 0.008). Prolonged pleural effusion (>21 days) increased the risk of experiencing protein-losing enteropathy (HR 4.7, 95% CI 2.0-11.1; P < 0.001).

CONCLUSIONS

With modern techniques, survival and freedom from Fontan failure are good. However, Fontan patients remain subject to general attrition. Tachyarrhythmia is an important sign for an adverse outcome. Prevention and early treatment of tachyarrhythmia may, therefore, be paramount in improving the long-term outcome.

Predictors of Early Postoperative Supraventricular Tachyarrhythmias in Children After the Fontan Procedure

Postoperative arrhythmias are a frequent and fatal complication after the Fontan operation. However, clinical evidence demonstrating early postoperative arrhythmias in children undergoing the Fontan operation is limited. This study aimed to evaluate the prevalence of arrhythmias and identify the predictors of early postoperative supraventricular tachyarrhythmias (SVTs) after the Fontan procedure.Data were analyzed from 80 pediatric patients who underwent Fontan procedures between April 2000 and December 2017 in a single-center retrospective study. Early postoperative SVTs were defined as arrhythmias within 30 days after the Fontan procedure. We divided the patients into two groups, with or without early postoperative arrhythmias, and the predictors of early postoperative arrhythmias were analyzed. A multivariate logistic regression analysis was performed to determine independent predictors of early postoperative SVTs after the Fontan procedure.Early postoperative SVTs were observed in 21 patients (26.3%). The most common arrhythmia was junctional ectopic tachycardia. After an adjustment, an atrioventricular valve regurgitation (AVVR) grade of ≥2 (odds ratio 10.54, 95% confidence interval 2.52 to 44.17, P = 0.001) and preoperative arrhythmias (odds ratio 26.49, 95% confidence interval 1.64 to 428.62, P = 0.021) were significant predictors of early postoperative SVTs after the Fontan operation.An AVVR grade ≥2 and preoperative arrhythmia were significant predictors associated with early postoperative SVTs. Intervention for AVVR may provide clinical benefit for preventing early postoperative arrhythmias after the Fontan operation.

Fontan with lateral tunnel is associated with improved survival compared with extracardiac conduit

OBJECTIVES

The study aim was to compare Fontan patients undergoing lateral tunnel (LT) versus extracardiac conduit (ECC) technique.

METHODS

Fontan patients (LT vs ECC) from January 2000 to December 2017 were analyzed retrospectively. Baseline characteristics were analyzed as covariates. Primary outcomes (ie, mortality, Fontan failure, thrombosis, and pacemaker implantation) were compared using time-to-event models. Subgroup analysis including only initially fenestrated cases and propensity score matching were performed.

RESULTS

Eight hundred one Fontan patients: LT (n = 638) versus ECC (n = 163) were included. Median follow-up time was 4.8 years (range, 1.1-10.8 years). Baseline characteristics were similar except for age: LT versus ECC: 2.6 years (range, 2.2-3.2 years) versus 3.1 years (range, 2.6-4.7 years) (P < .01) and mean pulmonary artery pressure: LT versus ECC: 12 mm Hg (11-15 mm Hg) versus 11 mm Hg (10-13 mm Hg) (P < .05). Early mortality was significantly higher in ECC versus LT group (3.1%; vs 0.5%; P < .05). Freedom from death, heart transplantation and Fontan failure were significantly longer in LT vs ECC (P < .01). After correcting for age, diagnosis, surgical technique, surgeon, mean pulmonary artery pressure, and fenestration, the ECC group showed worse freedom from death (hazard ratio, 2.8; P < .01) and Fontan failure (hazard ratio, 3.0; P < .01). No difference in pacemaker implantation rate was demonstrated (P = .25). Early fenestration closure was associated with higher risk of early (hazard ratio, 30.5) and late mortality (hazard ratio, 3.5). After matching, log-rank tests showed significant differences between the 2 groups for Fontan failure at 5 and 10 years (P < .01) and mortality at 5 years (P = .02).

CONCLUSIONS

When compared with ECC, LT Fontan is associated with better short and midterm outcomes. Spontaneous fenestration closure is an independent risk factor for early/late mortality.

Autologous Right Auricular Versus PTFE Cavopulmonary Lateral Tunnel: Influence of Surgical Technique on Arrhythmias

BACKGROUND

To compare the incidence of arrhythmias and the overall survival at long-term follow-up of the right auricular baffle technique (RA) versus Gore-Tex^® (GT) baffle as intra-atrial cavopulmonary lateral tunnel, as well as the Nakata index and tunnel dimensions on cardiac magnetic resonance.

METHODS

Data were retrospectively collected. Serial 24-hour Holter recordings and cardiac magnetic resonance findings of the two groups were compared.

RESULTS

There was no significant difference in the estimated freedom from arrhythmias (87% at 10 years and 78% at 15 years vs 80% at 10 years and 70% at 15 years in RA and GT, respectively; P = .44) nor cumulative survival (86% at 10 years and 84% at 15 years vs 97% at 10 years and 81% at 15 years in RA and GT, respectively; P = .8). Also, no difference between the groups was observed in the Nakata index. The tunnel dimensions on cardiac magnetic resonance were significantly wider in the RA group. In reference to other potential risk indicators, using Cox proportional hazard regression analysis, only age (5 years or older at the time of total cavopulmonary connection) was associated with an increased risk for both arrhythmia and mortality.

CONCLUSIONS

This study demonstrated that there was no difference in freedom from arrhythmias, Nakata index, or survival between the two groups. This study confirmed the growth potential of the right auricular tunnel. However, the growth of the tunnel did not influence the incidence of arrhythmias.

CRT Implantation in a Patient with Congenital Heart Malformation

Treatment of patients with functional single-ventricle physiology is achieved using surgical corrections known as the “Fontan Procedure”. Two separate blood circulations are created from the single-ventricle function. These are non-cyanogenic patients, but at high risk of developing HF. CRT implantation is an option to improve the functional class and EF.

Evaluation and Management of the Child and Adult With Fontan Circulation: A Scientific Statement From the American Heart Association

It has been 50 years since Francis Fontan pioneered the operation that today bears his name. Initially designed for patients with tricuspid atresia, this procedure is now offered for a vast array of congenital cardiac lesions when a circulation with 2 ventricles cannot be achieved. As a result of technical advances and improvements in patient selection and perioperative management, survival has steadily increased, and it is estimated that patients operated on today may hope for a 30-year survival of >80%. Up to 70 000 patients may be alive worldwide today with Fontan circulation, and this population is expected to double in the next 20 years. In the absence of a subpulmonary ventricle, Fontan circulation is characterized by chronically elevated systemic venous pressures and decreased cardiac output. The addition of this acquired abnormal circulation to innate abnormalities associated with single-ventricle congenital heart disease exposes these patients to a variety of complications. Circulatory failure, ventricular dysfunction, atrioventricular valve regurgitation, arrhythmia, protein-losing enteropathy, and plastic bronchitis are potential complications of the Fontan circulation. Abnormalities in body composition, bone structure, and growth have been detected. Liver fibrosis and renal dysfunction are common and may progress over time. Cognitive, neuropsychological, and behavioral deficits are highly prevalent. As a testimony to the success of the current strategy of care, the proportion of adults with Fontan circulation is increasing. Healthcare providers are ill-prepared to tackle these challenges, as well as specific needs such as contraception and pregnancy in female patients. The role of therapies such as cardiovascular drugs to prevent and treat complications, heart transplantation, and mechanical circulatory support remains undetermined. There is a clear need for consensus on how best to follow up patients with Fontan circulation and to treat their complications. This American Heart Association statement summarizes the current state of knowledge on the Fontan circulation and its consequences. A proposed surveillance testing toolkit provides recommendations for a range of acceptable approaches to follow-up care for the patient with Fontan circulation. Gaps in knowledge and areas for future focus of investigation are highlighted, with the objective of laying the groundwork for creating a normal quality and duration of life for these unique individuals.

Right Ventricular Dominance Is Associated With Inferior Outcomes After the Extracardiac Fontan

Background:

Investigations of ventricular dominance and outcomes after the Fontan procedure have shown conflicting results. This may be due to the inclusion of multiple modifications of the Fontan or the omission of recently identified complications of the procedure. We examined the association between right ventricular dominance (RVD) and morbidity/mortality in a contemporary cohort following the extracardiac (EC) Fontan.

Methods:

We studied all pediatric patients at our center who underwent a predominantly fenestrated EC Fontan from 2004 to 2016. Outcomes assessed were freedom from (1) Fontan failure (death, takedown, listing for transplantation) and (2) complication (arrhythmia requiring medication, postoperative pacemaker, or implantable cardioverter defibrillator requirement, stroke, thrombosis in the Fontan circuit, protein losing enteropathy, plastic bronchitis, New York Heart Association class >2). We defined the perioperative period as occurring before hospital discharge or within 30 days of the Fontan.

Results:

A total of 137 patients (median age: 34 months, 62% male, 60% RVD) underwent the EC Fontan. Median duration of follow-up was 5.8 years (interquartile range: 2.4-9.0). Freedom from any event was 82.5% (RVD = 77%, LVD = 91%, χ2(1) = 5.03, P = .025) and RVD was associated with reduced event-free survival (hazard ratio: 2.94, P = .02). No confounders were identified. In the perioperative period, RVD was associated with reduced complication-free survival ( P = .004). After this period, RVD was associated with reduced failure-free survival ( P = .003).

Conclusions:

In this contemporary, single-center cohort of EC Fontan patients, RVD was associated with inferior outcomes.

Prediction of heart failure and death in an adult population of Fontan patients

BACKGROUND

Late Fontan survivors are at high risk to experience heart failure and death. Therefore, the current study sought to investigate the role of non-invasive diagnostics as prognostic markers for failure of the systemic ventricle following Fontan procedure.

METHODS

This monocentric, longitudinal observational study included 60 patients with a median age of 24.5 (19-29) years, who were subjected to cardiac magnetic resonance imaging, echocardiography, cardiopulmonary exercise testing, and blood analysis. The primary endpoint of this study was decompensated heart failure with symptoms at rest, peripheral and/or pulmonary edema, and/or death.

RESULTS

During a follow-up of 24 months, 5 patients died and 5 patients suffered from decompensated heart failure. Clinical (NYHA class, initial surgery), functional (VO2 peak, ejection fraction, cardiac index), circulating biomarkers (N-terminal pro brain natriuretic peptide), and imaging parameters (end diastolic volume index, end systolic volume index, mass-index, contractility, afterload) were significantly related to the primary endpoint. Multi-variate regression analysis identified afterload as assessed by cardiac magnetic resonance imaging as an independent predictor of the primary endpoint (hazard ratio 1.98, 95% confidence interval 1.19-3.29, p = 0.009).

CONCLUSION

We identified distinct parameters of cardiopulmonary exercise testing, cardiac magnetic resonance imaging, and blood testing as markers for future decompensated heart failure and death in patients with Fontan circulation. Importantly, our data also identify increased afterload as an independent predictor for increased morbidity and mortality. This parameter is easy to assess by non-invasive cardiac magnetic resonance imaging. Its modulation may represent a potential therapeutic approach target in these high-risk patients.

Fontan-associated Liver Disease

Fontan-associated liver disease refers to the disturbance in the liver secondary to hemodynamic changes and systemic venous congestion following Fontan surgery. Although the natural history of this disease has not yet been established, patients with more advanced liver injury develop the complications of portal hypertension, such as ascites, variceal haemorrhage, or encephalopathy. Moreover, patients with Fontan surgery may have an increased risk of hepatocellular carcinoma. Periodic liver monitoring is essential to prevent this disease and provide early treatment of liver complications.

Ventricular assist device use in single ventricle congenital heart disease

As VAD have become an effective therapy for end-stage heart failure, their application in congenital heart disease has increased. Single ventricle congenital heart disease introduces unique physiologic challenges for VAD use. However, with regard to the mixed clinical results presented within this review, we suggest that patient selection, timing of implant, and center experience are all important contributors to outcome. This review focuses on the published experience of VAD use in single ventricle patients and details physiologic challenges and novel approaches in this growing pediatric and adult population.

Where Is the "Optimal" Fontan Hemodynamics?

Fontan circulation is generally characterized by high central venous pressure, low cardiac output, and slightly low arterial oxygen saturation, and it is quite different from normal biventricular physiology. Therefore, when a patient with congenital heart disease is selected as a candidate for this type of circulation, the ultimate goals of therapy consist of 2 components. One is a smooth adjustment to the new circulation, and the other is long-term circulatory stabilization after adjustment. When either of these goals is not achieved, the patient is categorized as having "failed" Fontan circulation, and the prognosis is dismal. For the first goal of smooth adjustment, a lot of effort has been made to establish criteria for patient selection and intensive management immediately after the Fontan operation. For the second goal of long-term circulatory stabilization, there is limited evidence of successful strategies for long-term hemodynamic stabilization. Furthermore, there have been no data on optimal hemodynamics in Fontan circulation that could be used as a reference for patient management. Although small clinical trials and case reports are available, the results cannot be generalized to the majority of Fontan survivors. We recently reported the clinical and hemodynamic characteristics of early and late failing Fontan survivors and their association with all-cause mortality. This knowledge could provide insight into the complex Fontan pathophysiology and might help establish a management strategy for long-term hemodynamic stabilization.

30-year experience of Fontan surgery: single-centre's data

Background

The Fontan procedure has been modified several times since it was introduced into practice in 1968. As many patients now survive to adulthood, attention is directed towards their clinical status and late morbidity. We report our surgical experience of 30 years in Fontan procedures.

Methods

From January 1985 to January 2015, 80 patients underwent Fontan surgery. Twenty-one patients received an atrio-pulmonary Fontan (Group I), four patients underwent total cavopulmonary connection (TCPC) with an intra-atrial lateral tunnel (Group II), six patients received extra-cardiac TCPC with an aortic homograft (group III) and 49 patients received extra-cardiac TCPC with an expanded polytetrafluoroethylene conduit. They were followed for early and late mortality, long-term survival, postoperative morbidity and reoperations.

Results

The mean follow-up time was 7.4 ± 6.6 years. The Kaplan–Meier estimated 15-year survival rate was 42% in Group I, 50% in Group II, 83% in Group III and 94% in Group IV. The median length of stay in intensive care unit, intubation and chest drain stay time were 90 h (IQR, 46–119), 8 h (IQR, 6–16) and 18 days (IQR, 12–28) respectively. Early complications were bleeding (6), taken down of Fontan circulation (3) and acute heart failure managed by left heart bypass (1). Late-occurring morbidities included arrhythmias (6), protein-losing enteropathy (2), thromboembolism (2) and tracheal stenosis (1). Fourteen patients (18%) had redo Fontan procedures.

Conclusion

Our series showed improving results after Fontan completion with excellent mid-term outcome after extra-cardiac TCPC with expanded polytetrafluoroethylene conduit. The long-term result should be followed.

Arrhythmia Surgery for Adults with Congenital Heart Disease

Patients with repaired or unrepaired congenital heart anomalies are at increased risk for arrhythmia development throughout their lives, often paralleling the need for reoperations for hemodynamic residua. The ability to incorporate arrhythmia surgery into reoperations can result in improvement in functional class and decreased need for antiarrhythmic medications. Every reoperation for congenital heart disease can be viewed as an opportunity to assess the electrical and arrhythmia substrates and to intervene to improve the arrhythmias and the hemodynamic condition of the patient. The authors review and summarize the operative techniques for arrhythmia surgery that are based on the arrhythmia mechanisms.