Natural and Modified History of Atrioventricular Valve Regurgitation in Patients With Fontan Circulation

Discordances in Kinetic Energy Between the Superior Cavopulmonary Connection and Single Ventricle Are Associated With Suboptimal Fontan Outcomes: A Pre-Fontan 4-Dimensional Flow Study

BACKGROUND

Patients with functional single ventricle (SV) are at risk for adverse outcomes after staged palliation from the superior cavopulmonary connection (SCPC) to the Fontan. Current pre-Fontan assessment by cardiac magnetic resonance and cardiac catheterization includes measuring atrioventricular valve regurgitation, aortopulmonary collateral burden, and pressures. Four-dimensional flow can quantify complex flows representing hemodynamic inefficiency. This study determined the clinical significance of kinetic energy (KE) and viscous energy loss in patients before the Fontan procedure using 4-dimensional flow.

METHODS AND RESULTS

This was a retrospective analysis of patients before the Fontan procedure who underwent ferumoxytol-enhanced cardiac magnetic resonance and same-day catheterization. Four-dimensional flow data sets were analyzed using ITFlow (CardioFlowDesign) to measure KE/viscous energy loss in the atrium, SV, and SCPC. A composite outcome was defined by rejected Fontan candidacy, prolonged hospitalization, lymphatic dysfunction, or heart failure. The relationship between these outcomes and KE/viscous energy loss was assessed by bivariable and multivariable logistic regression analyses as appropriate. Sixty-five patients (3.9±1.5 years, 0.64±0.1 m2) were included. Fifty (77%) proceeded to Fontan operation with median hospitalization time of 8.5 (interquartile range, 7-12.7) days. Twenty-six (40%) experienced a composite outcome, including 9 with rejected candidacy. Lower SCPC flow was associated with an outcome (P=0.042). Meanwhile, higher SV KE and lower SCPC KE were independently associated with composite outcome (odds ratio, 3.63 [95% CI, 1.32-13.2]; P=0.0263; odds ratio, 0.906 [95% CI, 0.814-0.980]; P=0.0377). Higher SV KE and lower SCPC KE corresponded to significant atrioventricular valve regurgitation, higher aortopulmonary collateral burden, and higher cathetherization pressures.

CONCLUSIONS

Four-dimensional flow analysis provides insight into SV hemodynamics and is associated with short-term outcomes. Future work will analyze the longitudinal implications for patients undergoing the Fontan procedure.

Systolic Function in the Fontan Circulation Is Exercise, but Not Preload, Recruitable

BACKGROUND

Fontan circulatory failure with impaired systolic function is well documented; however, its mechanisms are not fully understood. The aim of this study was to explore myocardial functional reserve in adolescent patients with Fontan circulation in response to exercise or acute preload increase.

METHODS

The study included 32 patients (median age, 16.7 years; range, 15.4-17.9 years; 12 female patients) with Fontan circulation. Echocardiographic imaging was performed during exercise using a recumbent cycle ergometer and during heart catheterization with a rapid infusion of 0.9% saline infusion at 5 mL/kg body weight. Myocardial peak longitudinal strain (LS) was measured in a four-chamber view during specific time intervals before, during, and after exercise (LSstress) and volume load (LScath). During catheterization, central venous pressure and ventricular end-diastolic pressure were simultaneously recorded. A control group of 16 healthy individuals participated in the exercise test.

RESULTS

Mean LSstress was less negative for patients than for control subjects (P ≤ .001 at all stages); however, it significantly improved from -18.4 ± 5.5% at baseline to -22.0 ± 6.5% (P = .004) at maximal loading. LSstress at maximal loading did not correlate with changes in heart rate. During catheterization, mean LScath was -19.6 ± 6.0% at baseline and did not improve significantly at 1.00 to 2.00 minutes and at 4.00 to 6.00 minutes after saline infusion. In more than half of the patients, LScath worsened or improved by less than -2% after saline infusion. Worsening of LScath correlated with central venous pressure and ventricular end-diastolic pressure in all conditions (P ≤ .017). There was no difference in LSstress or LScath between the morphologic right ventricle and the morphologic left ventricle.

CONCLUSIONS

Patients with Fontan circulation demonstrate systolic myocardial functional reserve that can be recruited with exercise stress but not with an acute increase in preload.

Outcomes of Fontan operation in patients with conotruncal anomalies from Australia and New Zealand Fontan Registry: a review of 1835 patients†

OBJECTIVES

The impact of conotruncal anomalies (CTAs), including tetralogy of Fallot, truncus arteriosus, ventriculo-arterial discordance, double-outlet right ventricle and interrupted aortic arch type B, on long-term outcomes remains poorly described in the Fontan cohort. We sought to review the outcomes of Fontan patients with CTAs in Australia and New Zealand.

METHODS

We reviewed the data from 1835 patients who underwent a Fontan operation between 1975 and 2023 from the Australia and New Zealand Fontan Registry.

RESULTS

CTAs occurred in 895 patients (49%), including D-TGA (Transposition of Great Arteries) (n = 476), double-outlet right ventricle (n = 360) and L-TGA (n = 170). Patients with CTAs had more heterotaxy syndrome (11.3% vs 6.8%, P < 0.001) and less left-ventricular dominance (53% vs 60%, P = 0.011). Median follow-up was 11.7 years (IQR: 5.3-20.3 years). Overall transplant-free survival and freedom from Fontan failure was 84% (95% confidence interval: 81-87%) and 72% (95% confidence interval: 68-75%) at 20 years, respectively. No difference was demonstrated in survival or freedom from Fontan failure between patients with or without CTAs (P = 0.50 and P = 0.83). Pacemaker implantation was more common in patients with CTAs (11.2% vs 8.3%, P = 0.038). Overall, 45 patients underwent outflow tract reinterventions, including semilunar valves, 'after' Fontan operation. Freedom from these reinterventions was 95% (95% confidence interval: 93-96%) at 30 years and was higher in patients with CTAs (P < 0.001).

CONCLUSIONS

Patients with CTAs did not have a demonstrable difference in long-term survival and freedom from Fontan failure to other patients undergoing Fontan operation. Patients with CTAs have higher incidence of outflow tract reinterventions, including semilunar valves, and higher rate of pacemaker implantation.

Single ventricle palliation in congenitally corrected transposition of the great arteries: An international multicenter study

BACKGROUND

Single ventricle palliation may be performed in patients with congenitally corrected transposition of the great arteries due to hypoplasia of 1 ventricle or anatomic complexity rendering biventricular repair unfeasible. There have been only a few small studies of the outcomes of single ventricle palliation in the setting of congenitally corrected transposition of the great arteries.

METHODS

A multicenter, international, retrospective cohort study of patients with congenitally corrected transposition of the great arteries undergoing single ventricle palliation was conducted in 29 tertiary hospitals in 6 countries from 1990 to 2018.

RESULTS

A total of 194 patients with congenitally corrected transposition of the great arteries underwent single ventricle palliation. A functionally univentricular heart was present in 62.4% (121/194). Patients with 2 good-sized ventricles had more laterality defects (50.7% vs 28.1%, P = .002). Fontan completion was achieved in 80.3% (155/194). A tricuspid valve surgery was performed in 9.3% (18/194). Survival was 97.4% (95% CI, 92.1-99.2) at 15 years in the univentricular cohort and 89.8% (95% CI, 78.0-95.5) at 15 years in those with 2 adequate ventricles (P = .05). At last follow-up, 11.5% of patients had heart failure, whereas 6.0% had moderate or greater systemic right ventricle dysfunction and 8.4% exhibited moderate or greater tricuspid regurgitation. In multivariable analysis, aortic coarctation or hypoplasia (hazard ratio, 7.7; P = .005) was associated with mortality.

CONCLUSIONS

Single ventricle palliation in patients with congenitally corrected transposition of the great arteries is associated with excellent long-term survival and low rates of heart failure and atrioventricular valve failure. In patients who would require complex surgery to achieve a biventricular repair, single ventricle palliation appears to be a good alternative.

Outcomes of extracardiac Fontan operation: A single institution experience with 398 patients

OBJECTIVE

The study objective was to evaluate the outcomes of the extracardiac Fontan operation at a single institution.

METHODS

We conducted a retrospective study of 398 patients from a single institution who underwent their initial extracardiac Fontan operation between 1997 and 2020. We determined the incidence of and risk factors for failure of the Fontan circulation, which includes death, Fontan takedown, heart transplantation, protein-losing enteropathy, plastic bronchitis, and functional status at the last follow-up.

RESULTS

The median follow-up time was 10.3 years (interquartile range, 6.4-14.6). The overall survival was 96% and 86% at 10 and 20 years after extracardiac Fontan operation, respectively. There were 6 early deaths (6/398, 1.5%) and 15 late deaths (15/398, 3.8%). Forty-nine patients (12.5%) developed failure of the Fontan circulation. Freedom from the failure of Fontan circulation was 88% at 10 years and 76% at 20 years. Risk factors for failure of the Fontan circulation were right ventricular dominance (hazard ratio, 4.7; P < .001; 95% CI, 2.1-10.5), aortic atresia (hazard ratio, 5.5; P < .001; 95% CI, 2.3-12.8), and elevated mean pulmonary artery pressure (hazard ratio, 2.3; P = .002; 95% CI, 1.2-6.7).

CONCLUSIONS

Rates of failure of the Fontan circulation are low after the contemporary extracardiac Fontan operation. Risk factors for failure of the extracardiac Fontan circulation include right ventricular dominance, aortic atresia, and elevated pulmonary artery pressures.

Occluded fenestration is associated with improved long-term outcomes in patients undergoing the fenestrated Fontan operation

OBJECTIVE

The modified Fontan operation, a palliative approach for patients with single ventricular circulation, often incorporates a fenestration to facilitate postoperative management. Postoperative fenestration closure sometimes is performed to mitigate potential risks such as low oxygen saturation. However, the benefits and potential risks of this procedure remain under investigation.

METHODS

A retrospective, propensity score-matching study was conducted at the National Taiwan University Children's Hospital. It included all patients who underwent their first fenestrated modified Fontan procedure between February 1998 and July 2020. The primary objective was to assess the incidence of death, Fontan takedown, and heart transplantation. Major adverse cardiovascular events were considered as a secondary outcome.

RESULTS

The study comprised 173 patients (male/female 100/73), with a median operation age of 4.6 years and a median follow-up of 10.4 years (interquartile range, 6.2-14.0 years) after operation. At the latest follow-up, fenestration was occluded in 74 patients (42.8%), with 29 undergoing transcatheter closure and 45 experiencing spontaneous occlusion. After propensity score matching, patients with occluded fenestration demonstrated significantly better event-free survival (15-year survival 95.3% vs 78.6%, P = .047), although the intention-to-treat fenestration closure group showed similar outcomes compared with the natural course group. High recent N-terminal pro-B-type natriuretic peptide and Fontan pressure emerged as critical risk factors for worse event-free survival and major adverse cardiovascular events. The cutoff points of N-terminal pro-B-type natriuretic peptide and Fontan pressure were 467.7 pg/mL and 18 mm Hg, respectively.

CONCLUSIONS

Patients with occluded fenestration exhibited superior event-free survival. Fenestration closure is a feasible strategy to enhance oxygen saturation without elevating Fontan pressure.

Tricuspid Valve Repair Can Restore the Prognosis of Patients with Hypoplastic Left Heart Syndrome and Tricuspid Valve Regurgitation: A Meta-analysis

To date, evidence supporting the efficacy of tricuspid valve (TV) repair in interrupting the progression of systemic right ventricular (RV) adverse remodeling in hypoplastic left heart syndrome (HLHS) is conflicting. We conducted a systematic review and meta-analysis of scientific literature to assess the impact of TV repair in effectively modifying the prognosis of patients with HLHS. We conducted a systematic review of PubMed, Web of Science, and Scopus databases. A random-effect meta-analysis was performed and transplant-free survival, freedom from TV regurgitation, and TV reoperation data were reconstructed using the published Kaplan-Meier curves. Nine studies were included, comprising 203 HLHS patients undergoing TV repair and 323 HLHS controls. The estimated transplant-free survival at 1, 5, and 10 years of follow-up was 75.5% [95% confidence interval (CI) = 67.6-84.3%], 63.6% [95% CI = 54.6-73.9%], and 61.9% [95% CI = 52.7-72.6%], respectively. Transplant-free survival was comparable to HLHS peers without TV regurgitation (p = 0.59). Five-year freedom from recurrence of TV regurgitation and freedom from TV reoperation was 57% [95% CI = 46.7-69.7%] and 63.6% [95% CI = 54.5-74.3%], respectively. Younger age and TV repair at the time of Norwood operation increased the risk of TV regurgitation recurrence and the need for TV reoperation. Our meta-analysis supports the efficacy of TV repair in favorably modifying the prognosis of patients with HLHS and TV regurgitation, reestablishing a medium-term transplant-free survival which is comparable to HLHS peers. However, durability of surgery and long-term fate of TV and RV performance are still unclear.

Effects of systemic ventricular assist in failing Fontan patients: a theoretical analysis using a computational model

Mechanical circulatory support is a potential treatment for failing Fontan patients. In this study, we performed a theoretical analysis using a computational model to clarify the effects of systemic ventricular assist device (VAD) in failing Fontan patients. Cardiac chambers and vascular systems were described using the time-varying elastance model and modified Windkessel model, respectively. A VAD was simulated as a nonlinear function. In systolic and diastolic ventricular dysfunction and atrioventricular valve regurgitation models, systemic VAD increased the cardiac index and decreased the central venous pressure (CVP). However, in the high pulmonary vascular resistance model, CVP became extremely high above 15 mmHg to maintain the cardiac index when the pulmonary vascular resistance index (PVRI) was above 5 Wood units m2. In Fontan patients with ventricular dysfunction or atrioventricular valve regurgitation, systemic VAD efficiently improves the hemodynamics. In Fontan patients with PVRI of > 5 Wood units m2, systemic VAD seems ineffective.

Impact of Atrioventricular Valve Intervention at Each Stage of Single Ventricle Palliation

Background: Significant atrioventricular valve dysfunction can be associated with mortality or need for transplant in functionally univentricular heart patients undergoing staged palliation. The purposes of this study are to characterize the impact of concomitant atrioventricular valve intervention on outcomes at each stage of single ventricle palliation and to identify risk factors associated with poor outcomes in these patients. Methods: The Society of Thoracic Surgeons Congenital Heart Surgery Database was queried for functionally univentricular heart patients undergoing single ventricle palliation from 2013 through 2022. Separate analyses were performed on cohorts corresponding to each stage of palliation (1: initial palliation; 2: superior cavopulmonary anastomosis; 3: Fontan procedure). Bivariate analysis of demographics, diagnoses, comorbidities, preoperative risk factors, operative characteristics, and outcomes with and without concomitant atrioventricular valve intervention was performed. Multiple logistic regression was used to identify predictors associated with operative mortality or major morbidity. Results: Concomitant atrioventricular valve intervention was associated with an increased risk of operative mortality or major morbidity for each cohort (cohort 1: 62% vs 46%, P < .001; cohort 2: 37% vs 19%, P < .001; cohort 3: 22% vs 14%, P < .001). Black race in cohort 1 (odds ratio [OR] 3.151, 95% CI 1.181-9.649, P = .03) and preterm birth in cohort 2 (OR 1.776, 95% CI 1.049-3.005, P = .032) were notable predictors of worse morbidity or mortality. Conclusions: Concomitant atrioventricular valve intervention is a risk factor for operative mortality or major morbidity at each stage of single ventricle palliation. Several risk factors are associated with these outcomes and may be useful in guiding decision-making.

High-Performing Fontan Patients: A Fontan Outcome Registry by Cardiac Magnetic Resonance Imaging Study

Background

Fontan patients exhibit decreased exercise capacity. However, there is a subset of high-performing Fontan (HPF) patients with excellent exercise capacity.

Objectives

This study aims to: 1) create a Fontan-specific percent predicted peak VO2 tool using exercise data; 2) examine clinical factors associated with HPF patients; and 3) examine late outcomes in HPF patients.

Methods

Patients in the multi-institutional Fontan Outcomes Registry Using CMR Examination above the age of 8 years who had a maximal exercise test were included. An HPF patient was defined as a patient in the upper Fontan-specific percent predicted peak VO2 quartile. Multivariable logistic regression was employed to investigate factors associated with the HPF and Cox regression was used to examine the association between HPF patients and late outcomes (composite of death or listing for cardiac transplant).

Results

The study included 813 patients (mean age: 20.2 ± 8.7 years). An HPF patient was associated with left ventricular morphology (OR: 1.50, P = 0.04), mixed morphology (OR: 2.23, P < 0.001), and a higher ejection fraction (OR: 1.31 for 10% increase, P = 0.01). Patients with at least moderate atrioventricular valve regurgitation, protein-losing enteropathy, or who were using psychiatric medications, were less likely to be an HPF patient. After a mean follow-up of 3.7 years, 46 (5.7%) patients developed a composite endpoint. HPF had a lower risk of death or listing for cardiac transplant (HR: 0.06 [95% CI: 0.01-0.25]).

Conclusions

Patients with HPF have more favorable outcomes when compared to patients with lower exercise capacity. This large registry data highlights the role of exercise testing in providing personalized care and surveillance post-Fontan.

Early dehiscence of a tricuspid valve annuloplasty ring in an adolescent with hypoplastic left heart syndrome presenting with unconjugated hyperbilirubinemia

We report a unique case of an adolescent patient with Fontan physiology presenting with unconjugated hyperbilirubinemia due to dehiscence of a tricuspid valve annuloplasty ring.

Heart Transplantation after Univentricular Palliation: Improved Outcomes and Increased Complexity

AIM

Heart transplantation (HT) in patients with failing univentricular circulation is often challenging. This is compounded by the ever-increasing number of patients with prior Norwood-type reconstruction of the aorta, large aortic root, and often dense adhesions from multiple prior operations. We aimed to elucidate differences in outcomes of HT in patients with prior univentricular palliations, with and without prior Norwood-type aortic arch reconstruction (ArchRec).

METHODS

All patients who underwent HT for failed univentricular palliation during the 1990-2022 period were included in the study.

RESULTS

Of 45 patients, 18 had undergone ArchRec. Hospital mortality improved in the recent era (17.4% before 2006 vs 0% after 2006; p=0.11), despite a higher proportion of patients with ArchRec (17.4% before 2006 vs 60.8% after 2006, p=0.002). Patients with ArchRec had a higher number of prior cardiac surgeries (4.1±1.5 vs 3.2±1.3, p=0.04), longer cardiopulmonary bypass time (320±23 vs 242±21 min, p=0.02), more concomitant arch reconstruction (33.3% vs 0%, p=0.02), greater need for post-HT extracorporeal membrane oxygenation (33.3% vs 3.7%; p=0.01) and longer hospital stay (37.1±30.5 days vs 23.6±11.8 days, p=0.04). Freedom from death or retransplantation for all patients was 91%, 73%, 67%, and 53% at 1, 5, 10, and 15-years, respectively. Prior ArchRec, Fontan procedure, and earlier eras were not risk factors for death.

CONCLUSIONS

The outcomes of HT after univentricular palliation have improved in recent times and low operative mortality can be achieved. Despite increased complexity, good similar outcomes can be achieved in patients with and without prior arch reconstruction regardless of the palliation stage.

Long-term impact of anatomic subtype in hypoplastic left heart syndrome after Fontan completion

BACKGROUND

Aortic atresia (AA)/mitral stenosis (MS) is a well-known risk factor for survival after Norwood; however, the effect of anatomical subtypes in those who survive surgical palliation is unknown.

METHODS

We performed a retrospective single-center study of patients with classic hypoplastic left heart syndrome (HLHS) who underwent Fontan at our center between August 1989 and July 2017. Clinical outcomes, as well as ventricular and atrioventricular-valve (AVV) function, were determined for each patient, and the effects of HLHS subtype were estimated using multivariable statistical analyses.

RESULTS

We included 418 patients with HLHS (AA/mitral atresia [MA] 153, AA/MS 100, aortic stenosis [AS]/MS 154, and AS/MA 11). The median follow-up period was 8.6 (interquartile range, 2.9-15.8) years. Overall transplant-free survival, cumulative incidence of AVV failure, and ventricular failure, which were defined by moderate dysfunction or greater or the necessity of surgical interventions, were 70.1%, 35.9%, and 17.9% at 20 years, respectively. Of the 3 major subtypes, AA/MS was associated with lower survival rate (AA/MA 74.6% vs AS/MS 79.1% vs AA/MS 56.1% at 17 years, P = .04). The subanalysis between AA/MA and AA/MS revealed AA/MS tended to have a greater rate of ventricular failure without a significant difference of AVV failure (AA/MA 11.2% vs AA/MS 26.2% at 17 years, P = .053).

CONCLUSIONS

The survival risk of the anatomic subtype AA/MS persisted long term after Fontan completion and was likely due to a greater rate of single ventricle rather than AVV failure. These findings suggest that the abnormal pressure overload condition of the hypoplastic left ventricle created by AA/MS has a detrimental effect on single right ventricle function.

Validating the Concept of Mechanical Circulatory Support with a Rotary Blood Pump in the Inferior Vena Cava in an Ovine Fontan Model

Right-sided mechanical support of the Fontan circulation by existing devices has been compounded by the cross-sectional design of vena cava anastomosis to both pulmonary arteries. Our purpose was to investigate whether increasing inferior vena cava (IVC) flow with a rotary blood pump in the IVC only in an ovine animal model of Fontan would lead to acceptable superior vena cava (SVC) pressure. To achieve this, a Fontan circulation was established in four female sheep by anastomosing the SVC to the main pulmonary artery (MPA) and by interposing a Dacron graft between the IVC and the MPA. A rotary blood pump was then introduced in the graft, and the effect of incremental flows was observed at increasing flow regimen. Additionally, to stimulate increased pulmonary resistance, the experience was repeated in each animal with the placement of a restrictive band on the MPA distally to the SVC and Dacron graft anastomosis. Circulatory support of IVC flow alone increased the systemic cardiac output significantly, both with and without banding, indicating the feasibility of mechanical support of the Fontan circulation by increasing the flow only in the inferior vena cava. The increase in SVC pressure remained within acceptable limits, indicating the potential effectiveness of this mode of support. The findings suggest that increasing the flow only in the inferior vena cava is a feasible method for mechanical support of the Fontan circulation, potentially leading to an increase in cardiac output with acceptable increases in superior vena cava pressure.

Early and long-term outcomes following cardiac surgery for patients with heterotaxy syndrome

Objective

Heterotaxy syndrome is a complex multisystem abnormality historically associated with high morbidity and mortality. We sought to evaluate the early and long-term outcomes after cardiac surgery in heterotaxy syndrome.

Methods

This is a single-center retrospective review of patients with heterotaxy syndrome undergoing single-ventricle palliation or primary or staged biventricular repair from 1998 to 2018. Patients were stratified by single ventricle versus biventricular physiology, and the severity of atrioventricular valve regurgitation. Demographics, anatomic characteristics, and early and late outcomes, including the length of stay, mortality, and surgical or catheter reinterventions, were analyzed.

Results

Among 250 patients, 150 (60%) underwent biventricular repair. In-hospital mortality was 7.6% (n = 19). Median follow-up was 5.2 (range, 0-16) years. Among survivors to discharge, mortality was 19% (n = 44) and reintervention was 52% (n = 120). Patients with moderate/severe atrioventricular valve regurgitation were older (32 vs 16 months, P = .02), were more likely to experience adverse events during their index surgical admission (72% vs 46%, P < .001), and had longer in-hospital length of stay (20 vs 12 days, P = .009). Among patients with moderate to severe atrioventricular valve regurgitation, single-ventricle palliation is associated with a greater risk of unplanned reintervention compared with patients undergoing biventricular repair (hazard ratio, 2.13; CI, 1.10-4.12; P = .025).

Conclusions

There was no significant difference in early or late outcomes in single-ventricle versus biventricular repair strategies in heterotaxy. In the subgroup of patients with moderate/severe atrioventricular valve regurgitation, patients who underwent single-ventricle palliation were 2.5 times more likely to need a late reintervention compared with those undergoing biventricular repair.

Introduction of transcatheter edge-to-edge repair in patients with congenital heart disease at a children's hospital

BACKGROUND

Atrioventricular valve regurgitation (AVVR) is a devastating complication in children and young adults with congenital heart disease (CHD), particularly in patients with single ventricle physiology. Transcatheter edge-to-edge repair (TEER) is a rapidly expanding, minimally invasive option for the treatment of AVVR in adults that avoids the morbidity and mortality associated with open heart surgery. However, application of TEER in in CHD and in children is quite novel. We describe the development of a peri-procedural protocol including image-derived pre-intervention simulation, with successful application to four patients.

AIMS

To describe the initial experience using the MitraClip system for TEER of dysfunctional systemic atrioventricular valves in patients with congential heart disease within a pediatric hospital.

METHODS

A standardized screening and planning process was developed using cardiac magnetic resonance imaging, three dimensional echocardiography and both virtual and physical simulation. Procedures were performed using the MitraClip G4 system and patients were clinically followed post-intervention.

RESULTS

A series of four CHD patients with at least severe AVVR were screened for suitability for TEER with the MitraClip system: three patients had single ventricle physiology and Fontan palliation, and one had repair of a common atrioventricular canal defect. Each patient had at least severe systemic AVVR and was considered at prohibitively high risk for surgical repair. Each patient underwent a standardized preprocedural screening protocol and image-derived modeling followed by the TEER procedure with successful clip placement at the intended location in all cases.

CONCLUSIONS

The early results of our protocolized efforts to introduce TEER repair of severe AV valve regurgitation with MitraClip into the CHD population within our institution are encouraging. Further investigations of the use of TEER in this challenging population are warranted.

Clair N, Azcue N, Toro-Salazar OH, Rathod RH. How Good Are Cardiologists at Predicting Major Adverse Events in Fontan Patients?

Background

It is unknown how well cardiologists predict which Fontan patients are at risk for major adverse events (MAEs).

Objectives

The purpose of this study was to examine the accuracy of cardiologists' ability to identify the "good Fontan" patient, free from MAE within the following year, and compare that predicted risk cohort to patients who experienced MAE.

Methods

This prospective, multicenter study included patients ≥10 years with lateral tunnel or extracardiac Fontan. The cardiologist was asked the yes/no "surprise" question: would you be surprised if your patient has a MAE in the next year? After 12 months, the cardiologist was surveyed to assess MAE. Agreement between cardiologist predictions of MAE and observed MAE was determined using the simple kappa coefficient. Multivariable generalized linear mixed effects models were performed to identify factors associated with MAE.

Results

Overall, 146 patients were enrolled, and 99/146 (68%) patients w`ere predicted to be a "good Fontan." After 12 months, 17 (12%) experienced a MAE. The simple kappa coefficient of cardiologists' prediction was 0.17 (95% CI: 0.02-0.32), suggesting prediction of MAE was 17% better than random chance. In the multivariable cardiologist-predicted MAE (N = 47) model, diuretic/beta-blocker use (P ≤ 0.001) and systolic dysfunction (P = 0.005) were associated with MAE. In the observed multivariable MAE (N = 17) model, prior unplanned cardiac admission (P = 0.006), diuretic/beta-blocker use (P = 0.028), and ≥moderate atrioventricular valve regurgitation (P = 0.049) were associated with MAE.

Conclusions

Cardiologists are marginally able to predict which Fontan patients are at risk for MAE over a year. There was overlap between factors associated with a cardiologist's prediction of risk and observed MAE, namely the use of diuretic/beta-blocker.

Long-term follow-up of atrioventricular valve function in Fontan patients: effect of atrioventricular valve surgery

OBJECTIVES

The aim of this study was to evaluate the relationship between atrioventricular valve and ventricular function in Fontan survivors, including the effect of atrioventricular valve surgery.

METHODS

Analysis focused on transplant-free survival and the need for atrioventricular valve surgery in single ventricle patients after Fontan completion. Longitudinal echocardiographic examination of long-term valve and ventricular function was performed.

RESULTS

Fontan completion was performed in 113 patients, having a right univentricular morphology in 33.6%, a left ventricle morphology in 62.8% and ambiguous in 3.6%. Perioperative mortality was 2.7% (n = 3). Within a median follow-up of 16.3 years (interquartile range 10.6-23.6), transplant-free survival was 96.1 ± 1.9% and 90.4 ± 5.8% at 10-25 years. Twenty AV valve procedures were performed in 14 (12.4%) children, respectively, pre-Fontan (n = 10), per-Fontan (n = 8) and post-Fontan (n = 2), resulting in a cumulative incidence of AV valve surgery is 5.7 ± 2.2% and 12.3 ± 3.2% at 1-5 years. Atrio-ventricular valve function deteriorated over time [hazard ratio (HR) 1.112, 95% confidence interval (CI) 1.089-1.138, P < 0.001], without difference for valve morphology (P = 0.736) or ventricular dominance (P = 0.484). AV valve dysfunction was greater in patients requiring AV valve surgery (HR 20.383, 95% CI 6.223-36.762, P < 0.001) but showed a comparable evolution since repair to those without valve surgery (HR 1.070, 95% CI 0.987-1.160, P = 0.099). Progressive time-related ventricular dysfunction was observed (HR 1.141, 95% CI 1.097-1.182, P < 0.001), significantly less in left ventricle-dominance (HR 0.927, 95% CI 0.860-0.999, P = 0.047) but more after AV valve surgery (HR 1.103, 95% CI 1.014-1.167, P = 0.022).

CONCLUSIONS

In a homogeneously treated Fontan population, 25-year transplant-free survival is encouraging. Atrio-ventricular valve surgery was necessary in 12.4%, resulting mostly in a durable valve function. However, a slow time-related decline of atrioventricular valve function as of ventricular function is worrisome, evoking a role for additional heart failure therapy.

Long-term outcomes of tricuspid valve intervention during stage 2 palliation in patients with a single right ventricle

OBJECTIVES

In patients with single ventricle physiology and a systemic right ventricle, tricuspid valve regurgitation increases the risk of adverse outcomes, and tricuspid valve intervention at the time of staged palliation further increases that risk in the postoperative period. However, long-term outcomes of valve intervention in patients with significant regurgitation during stage 2 palliation have not been established. The purpose of this study is to evaluate the long-term outcomes after tricuspid valve intervention during stage 2 palliation in patients with right ventricular dominant circulation in a multicenter study.

METHODS

The study was performed using the Single Ventricle Reconstruction Trial and Single Ventricle Reconstruction Follow-up 2 Trial datasets. Survival analysis was performed to describe the association among valve regurgitation, intervention, and long-term survival. Cox proportional hazards modeling was used to estimate the longitudinal association of tricuspid intervention and transplant-free survival.

RESULTS

Patients with tricuspid regurgitation at stage 1 or 2 had worse transplant-free survival (hazard ratio, 1.61; 95% confidence interval, 1.12-2.32; hazard ratio, 2.3; 95% confidence interval 1.39-3.82). Those with regurgitation who underwent concomitant valve intervention at stage 2 were significantly more likely to die or undergo heart transplantation compared with those with regurgitation who did not (hazard ratio, 2.93; confidence interval, 2.16-3.99). Patients with tricuspid regurgitation at the time of the Fontan had favorable outcomes regardless of valve intervention.

CONCLUSIONS

The risks associated with tricuspid regurgitation in patients with single ventricle physiology do not appear to be mitigated by valve intervention at the time of stage 2 palliation. Patients who underwent valve intervention for tricuspid regurgitation at stage 2 had significantly worse survival compared with patients with tricuspid regurgitation who did not.

Risk of in-hospital Deterioration for Children with Single Ventricle Physiology

Children with single ventricle physiology (SV) are at high risk of in-hospital morbidity and mortality. Identifying children at risk for deterioration may allow for earlier escalation of care and subsequently decreased mortality.We conducted a retrospective chart review of all admissions to the pediatric cardiology non-ICU service from 2014 to 2018 for children < 18 years old. We defined clinical deterioration as unplanned transfer to the ICU or inpatient mortality. We selected children with SV by diagnosis codes and defined infants as children < 1 year old. We compared demographic, vital sign, and lab values between infants with and without a deterioration event. We evaluated vital sign and medical therapy changes before deterioration events.Among infants with SV (129 deterioration events over 225 admissions, overall 25% with hypoplastic left heart syndrome), those who deteriorated were younger (p = 0.001), had lower baseline oxygen saturation (p = 0.022), and higher baseline respiratory rate (p = 0.022), heart rate (p = 0.023), and hematocrit (p = 0.008). Median Duke Pediatric Early Warning Score increased prior to deterioration (p < 0.001). Deterioration was associated with administration of additional oxygen support (p = 0.012), a fluid bolus (p < 0.001), antibiotics (p < 0.001), vasopressor support (p = 0.009), and red blood cell transfusion (p < 0.001).Infants with SV are at high risk for deterioration. Integrating baseline and dynamic patient data from the electronic health record to identify the highest risk patients may allow for earlier detection and intervention to prevent clinical deterioration.

Valvular Regurgitation in Adults with Congenital Heart Disease and Heart Failure: Current Status and Potential Interventions

The great majority of patients born with congenital heart disease (CHD) are living well into adulthood, yet they often have residual hemodynamic lesions, including valvar regurgitation. As these complex patients grow older, they are at risk of developing heart failure, which can be exacerbated by the underlying valvular regurgitation. In this review, we describe the etiologies of heart failure related to valvular regurgitation in the CHD population and discuss potential interventions.

Liver Cirrhosis After the Fontan Procedure: Impact of Atrioventricular Valve Failure

BACKGROUND

Liver cirrhosis is now well recognized as a potential complication after the Fontan procedure, although associated risk factors and optimal timing of liver screening remain unclear.

METHODS

All patients who underwent an extracardiac conduit Fontan procedure at The Royal Children's Hospital, Melbourne, were identified using the Australia and New Zealand Fontan Registry. Cirrhosis was diagnosed based on liver biopsy, or a combination of imaging findings and clinical evaluation by a hepatologist.

RESULTS

Between 1997 and 2020, 398 patients underwent an extracardiac conduit Fontan procedure at our center, and 276 had ongoing follow-up in Victoria. Ninety-five patients (34%) underwent liver assessment at a mean age of 18.2 ± 6.7 years (11.8 ± 5.5 years post-Fontan). Fifteen patients (16%) were diagnosed with cirrhosis at a mean age of 22.7 ± 5.9 years (14.0 ± 5.2 years post-Fontan). The need for prior or concomitant atrioventricular valve repair or replacement was associated with an increased risk of cirrhosis (univariable hazard ratio [HR] 7.09, 95% confidence interval [CI] 2.13-23.61, P = .001). By multivariable analysis, factors associated with development of cirrhosis were atrioventricular valve failure prior to Fontan (HR 3.27, 95% CI 1.15-9.31, P = .026) and older age at Fontan operation (HR 1.13 per year increase, 95% CI 1.01-1.26, P = .034). The proportion of patients alive, nontransplanted, and without cirrhosis at 10, 15, and 20 years was 93.4% (95% CI 88.4%-98.7%), 79.6% (95% CI 69.7%-90.8%), and 64.6% (95% CI 51.0%-81.9%), respectively.

CONCLUSIONS

Early commencement of liver screening should be considered for patients with a history of atrioventricular failure during Fontan palliation.