Long-term outcome after atrioventricular valve surgery following modified Fontan operation

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.

Atrioventricular septal defect in Fontan circulation: Right ventricular dominance, not valve surgery, adversely affects survival

OBJECTIVE

The effect of ventricular dominance and previous atrioventricular valve (AVV) surgery on patient outcomes after Fontan operation remains unclear. We sought to determine the effect of ventricular dominance and previous AVV surgery on transplantation-free survival and long-term AVV competency in patients with atrioventricular septal defect (AVSD) and Fontan circulation.

METHODS

We conducted a retrospective study of 1703 patients in the Australia and New Zealand Fontan Registry, who survived Fontan operation between 1987 and 2021.

RESULTS

Of 174 patients with AVSD, 60% (105/174) had right ventricular (RV) dominance and 40% (69/174) had left ventricular (LV) dominance. The cumulative incidence of moderate or greater AVV regurgitation at 25 years after Fontan operation in patients with LV dominance was 56% (95% CI, 35%-72%), compared with 54% (95% CI, 40%-67%) in patients with RV dominance (P = .6). Nonetheless, transplantation-free survival at 25 years in patients with LV dominance was 94% (95% CI, 86%-100%), compared with 67% (95% CI, 52%-87%) in patients with RV dominance (hazard ratio, 5.9; 95% CI, 1.4-25.4; P < .01). Of note, transplantation-free survival was not different in patients who underwent AVV surgery before or at Fontan completion compared with those who did not (15 years: 81% [95% CI, 62%-100%] vs 88% [95% CI, 81%-95%]; P = .3).

CONCLUSIONS

In patients with AVSD and Fontan circulation the rate of moderate or greater common AVV regurgitation is similar in those with LV and RV dominance. RV dominance, rather than previous AVV surgery, is a risk factor for death or transplantation.

First described mitral clip in an adult extracardiac Fontan patient: a case report

Background

The use of transcatheter edge-to-edge repair (TEER) in patients with advanced heart failure has been shown to reduce hospitalizations and increase survival. As patients with Fontan circulations grow older, a significant proportion of them will develop severe atrioventricular (AV) valve regurgitation in the systemic ventricle. Conventional surgical repair and transplant carry high mortality risk for the adult Fontan patient with progressive heart failure.

Case summary

A 51-year-old female extracardiac Fontan patient developed severe AV valve regurgitation and progressive functional decline. Based on her operative risk for conventional surgical intervention or transplant, TEER using the Abbott MitraClip device was performed. The degree of mitral regurgitation was decreased from severe to moderate regurgitation.

Discussion

This is the first known case describing the use of a successful TEER in an adult patient with an extracardiac Fontan. Given the increasing numbers of patients surviving into adulthood with a Fontan circulation, transcatheter interventions may provide an alternative treatment option to conventional surgeries and medical therapies.

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.

Long-term results of concomitant atrioventricular valve intervention and the Fontan operation

OBJECTIVES

The optimal timing for atrioventricular valve (AVV) repair in patients with a Fontan circulation remains controversial. Few studies have reported the long-term outcomes of AVV repair concomitant with a Fontan operation.

METHODS

From January 2006 to December 2018, a total of 89 patients who developed moderate or severe AVV regurgitation before a Fontan operation were divided into 2 groups: group 1, including 37 patients who did not undergo concomitant AVV repair; and group 2, including 52 patients who received AVV repair concomitant with a Fontan operation.

RESULTS

The mean age at the time of the Fontan operation was 6.74 years for group 1 and 8.96 years for group 2, respectively. Early death occurred in 3 patients [2 patients (5.4%) in group 2, patient 1 (1.9%) in group 1]. Freedom from long-term death, cardiac function reduction and protein-losing enteropathy were similar among the 2 groups. Common AVV function was apparently poorer than mitral valve function after repair [hazard ratio (HR) 3.83, 95% confidence interval (CI) 1.31-11.17; P = 0.014]. The occurrence of AVV valve failure in group 1 was lower than that in group 2 (HR 0.44, 95% CI 0.22-0.91; P = 0.026). AVV function became worse during the follow-up period than that at discharge in both groups (P = 0.03 in group 1 and P = 0.001 in group 2).

CONCLUSIONS

The long-term results of AVV repair concomitant with a Fontan operation are favourable.

Effect of Earlier Atrioventricular Valve Intervention on Survival After the Fontan Operation

Whereas the prevalence and impact of atrioventricular valve (AVV) regurgitation in patients with single ventricle physiology has become increasingly apparent, the optimal timing for valve intervention is unclear. To investigate this, we performed a retrospective review of all 1,167 patients from the Mayo Clinic Fontan database. Thirteen percent (153 patients) had AVV repair or replacement during their staged single ventricle palliation. We found that patients with right ventricular morphology and common AVV were at increased risk for AVV intervention. Patients who underwent AVV intervention had increased risk of death/transplant compared with those who did not (hazards ratio [HR] = 1.75, 95% CI 1.37 to 2.23, p <0.001). With respect to valve intervention timing, whereas AVV intervention before Fontan presented similar risk for death/transplant compared with no AVV intervention (HR = 0.85, 95% CI 0.32 to 2.27, p = 0.74), intervention at time of Fontan had a significantly higher risk (HR = 1.46, 95% CI 1.09 to 1.97, p = 0.01), and intervention after Fontan had a much more substantial risk (HR = 3.83, 95% CI 2.54 to 5.79, p <0.001). AVV repair failure occurred in 11% of patients. In terms of relative risk of valve repair versus replacement, in post-Fontan AVV intervention patients, AVV replacement carried a 2.9 fold risk of death/transplant compared with AVV repair. In conclusion, AVV disease remains a considerable challenge for durable Fontan physiology. This data demonstrates that earlier intervention on valve pathology improves survival with the Fontan circulation. Continued surveillance of single ventricle patients and prompt referral of those with valve pathology can improve outcomes in this challenging population.

Atrioventricular Valve Regurgitation in Single Ventricle Heart Disease: A Common Problem Associated With Progressive Deterioration and Mortality

The Fontan procedure has provided patients with single ventricle physiology extended survival into adulthood and in many cases has improved their quality of life. Atrioventricular valve regurgitation (AVVR) is common in single ventricle patients and is associated with increased risk of mortality. AVVR is more common in patients with a systemic tricuspid or common atrioventricular valve but is generally progressive irrespective of underlying valve morphology. AVVR can be attributable to diverse structural and functional abnormalities at multiple levels of the valvar apparatus, as well as ventricular dysfunction and dilation. Multiple imaging modalities including recent advances in 3‐dimensional echocardiography and cross‐sectional imaging have been used to further understand AVVR. Surgery to address AVVR must be tailored to the underlying mechanism and the timing of surgical repair should be chosen carefully. In this review, we discuss the etiologies, treatment options, surgical timing, and outcomes of valve repair or replacement for AVVR in patients with single ventricle congenital heart disease, with a focus on those with a Fontan circulation as AVVR is associated with increased risk for Fontan failure and mortality. In‐depth understanding of the current literature will help guide clinicians in their approach and management of AVVR in this population.

Atrioventricular Valve Failure in Fontan Palliation

BACKGROUND

Atrioventricular valve failure (moderate or greater regurgitation, or valve operation) is a risk factor for adverse outcomes in patients undergoing Fontan palliation.

OBJECTIVES

This study determined the incidence of atrioventricular valve failure and its clinical impact on patients undergoing Fontan palliation.

METHODS

A retrospective cohort longitudinal study was conducted using patient data extracted from an existing bi-national, population-based registry.

RESULTS

A total of 1,468 patients who underwent Fontan palliation were identified; complete follow-up data were available for 1,199 patients. Six hundred eighty-six patients had 2 atrioventricular valves, 286 had a single mitral valve, 130 had a common atrioventricular valve, and 97 had a single tricuspid valve. A total of 132 repairs were performed in 110 patients, and 15 replacements were performed in 13 patients. The cumulative incidence of atrioventricular valve failure at 25 years of age for patients with a common atrioventricular, single tricuspid, single mitral, and 2 atrioventricular valves was 56% (95% confidence interval [CI]: 46% to 67%), 46% (95% CI: 31% to 61%), 8% (95% CI: 4% to 12%), and 26% (95% CI: 21% to 30%), respectively. In patients without valve failure, freedom from Fontan failure at 10 and 20 years post-Fontan palliation was 91% (95% CI: 89% to 93%) and 77% (95% CI: 73% to 81%), respectively, compared with 77% (95% CI: 69% to 85%) and 54% (95% CI: 42% to 68%), respectively, in patients with valve failure (hazard ratio: 2.43; 95% CI: 1.74 to 3.39; p < 0.001).

CONCLUSIONS

Atrioventricular valve failure occurs frequently in patients undergoing Fontan palliation. Patients with valve failure are twice as likely to have their Fontan circulation fail than those without valve failure.

Feasibility of Computational Fluid Dynamics for Evaluating the Intraventricular Hemodynamics in Single Right Ventricle Based on Echocardiographic Images

This study introduced a combined computational fluid dynamics (CFD) and echocardiography methodology to simulate blood flow in the single right ventricle (SRV) and normal ventricles to study the intraventricular flow. Derived from echocardiographic image loops, CFD-based three-dimensional (3D) flow models of normal subject's left ventricle (LV) and right ventricle (RV) and SRV with and without heart failure at three characteristic diastolic statuses were reconstructed. The CFD derived morphological and functional measurements in normal ventricles and the SRV were validated with echocardiography. The vortex in the normal ventricles and the SRV were studied. The morphological and functional measurements derived from CFD modeling and echocardiography were comparable, and both methods demonstrated the larger volume and higher spherical index in the SRV, in particular the SRV with heart failure. All the vortices in the SRV were smaller than those in the normal control subject's LV and RV, notably with heart failure. Unlike normal LV and RV, no vortex ring was observed in the SRV. Echocardiography-based CFD demonstrated the feasibility of quantifying ventricular morphology and function; in addition, CFD can detect the abnormal flow pattern (smaller or obliterated vortices) in the SRV when compared with normal ventricles.

Assessment of Diastolic Function in Single-Ventricle Patients After the Fontan Procedure

BACKGROUND

Patients with functional single ventricles after the Fontan procedure have abnormal cardiac mechanics. The aims of this study were to determine factors that influence diastolic function and to describe associations of diastolic function with current clinical status.

METHODS

Echocardiograms were obtained as part of the Pediatric Heart Network Fontan Cross-Sectional Study. Diastolic function grade (DFG) was assessed as normal (grade 0), impaired relaxation (grade 1), pseudonymization (grade 2), or restrictive (grade 3). Studies were also classified dichotomously (restrictive pattern present or absent). Relationships between DFG and pre-Fontan variables (e.g., ventricular morphology, age at Fontan, history of volume-unloading surgery) and current status (e.g., systolic function, valvar regurgitation, exercise performance) were explored.

RESULTS

DFG was calculable in 326 of 546 subjects (60%) (mean age, 11.7 ± 3.3 years). Overall, 32% of patients had grade 0, 9% grade 1, 37% grade 2, and 22% grade 3 diastolic function. Although there was no association between ventricular morphology and DFG, there was an association between ventricular morphology and E', which was lowest in those with right ventricular morphology (P < .001); this association remained significant when using Z scores adjusted for age (P < .001). DFG was associated with achieving maximal effort on exercise testing (P = .004); the majority (64%) of those not achieving maximal effort had DFG 2 or 3. No additional significant associations of DFG with laboratory or clinical measures were identified.

CONCLUSIONS

Assessment of diastolic function by current algorithms results in a high percentage of patients with abnormal DFG, but few clinically or statistically significant associations were found. This may imply a lack of impact of abnormal diastolic function on clinical outcomes in this cohort, or it may indicate that the methodology may not be applicable to pediatric patients with functional single ventricles.

Recanalisation of the left superior caval vein after Fontan procedure: not so rare complication: possibilities of percutaneous closure using various devices

AIM

Evaluation of possibilities of percutaneous closure of recanalised left superior caval vein after total cavopulmonary connection.

METHODS AND RESULTS

We analysed 19 patients after total cavopulmonary connection catheterised because of a sudden increase of desaturation. In four of them, the recanalisation of the left superior caval vein was identified. For this reason, the balloon occlusion tests of the veins were made temporarily. In all cases, the haemodynamic status of patients did not change, and arterial oxygen saturation increased significantly. Thus, using different types of implants, these veins were closed effectively in all patients. During the short-term follow-up, the effectiveness of treatments and constantly maintaining a high level of saturation were confirmed.

CONCLUSIONS

Meticulous investigation of unclear causes of desaturation in cyanotic patients after Fontan completion is necessary. Almost all causes of desaturation, including recanalised additional left superior caval vein, can be effectively treated percutaneously.

Clinical outcomes and improved survival in patients with protein-losing enteropathy after the Fontan operation

BACKGROUND

Patients with protein-losing enteropathy (PLE) following the Fontan operation have a reported 50% mortality at 5 years after diagnosis.

OBJECTIVES

The aim of this study was to review outcomes in patients with PLE following the Fontan operation.

METHODS

From 1992 to 2010, 42 patients (55% male) with PLE following the Fontan operation were identified from clinical databases at the Mayo Clinic. Data were collected retrospectively.

RESULTS

Mean age at PLE diagnosis was 18.9 ± 11.0 years. Initial Fontan operation was performed at 10.1 ± 10.8 years of age. Mean time from Fontan operation to PLE diagnosis was 8.4 ± 14.2 years. Survival was 88% at 5 years. Decreased survival was seen in patients with high Fontan pressure (mean >15 mm Hg; p = 0.04), decreased ventricular function (ejection fraction <55%; p = 0.03), and New York Heart Association functional class >2 at diagnosis (p = 0.04). Patients who died had higher pulmonary vascular resistance (3.8 ± 1.6 Wood units [WU] vs. 2.1 ± 1.1 WU; p = 0.017), lower cardiac index (1.6 ± 0.4 l/min/m(2) vs. 2.7 ± 0.7 l/min/m(2); p < 0.0001), and lower mixed venous saturation (53% vs. 66%; p = 0.01), compared with survivors. Factors were assessed at the time of PLE diagnosis. Treatments used more frequently in survivors with PLE included spironolactone (21 [68%]), octreotide (7 [21%]), sildenafil (6 [19%]), fenestration creation (15 [48%]), and relief of Fontan obstruction (7 [23%]).

CONCLUSIONS

PLE remains difficult to treat; however, in the current era, survival has improved with advances in treatment. Further study is needed to better understand the mechanism of disease and ideal treatment strategy.

Protein losing enteropathy secondary to a pulmonary artery stent

A 2-year-old patient with hypoplastic left heart syndrome presented 6 months following Fontan completion with protein-losing enteropathy (PLE). He had undergone stent implantation in the left pulmonary artery after the Norwood procedure, followed by redilation of the stent prior to Fontan completion. Combined bronchoscopic and catheterization studies during spontaneous breathing confirmed left bronchial stenosis behind the stent, and diastolic systemic ventricular pressure during expiration of 25 mm Hg. We postulate that the stent acts as a valve, against which the patient generates high expiratory pressures, which are reflected in the ventricular diastolic pressure. This may be the cause of PLE.

Changing lesion demographics of the adult with congenital heart disease: an emerging population with complex needs

The demography of congenital heart disease is changing. Largely as a consequence of successful cardiac surgery in childhood, there are an increasing number of adults with congenital heart disease with a prevalence of more than four per 100 adults. The type of disease in adults is also changing with an increasing number of survivors with complex disease. These patients have a significantly increased healthcare requirement in comparison to healthy adults and this includes noncardiac, multisystem morbidity. The adult congenital heart disease population are now developing problems associated with aging and there is a new population of geriatrics with congenital heart disease. As survival continues to improve, increased healthcare resources need to be directed towards the management of the adult with congenital heart disease.