Atrioventricular valve replacement in patients with a single ventricle

Atrioventricular valve surgery in patients with univentricular heart and two separate atrioventricular valves

OBJECTIVES

Atrioventricular valve regurgitation in patients with univentricular heart is a well-known risk factor for adverse outcomes and atrioventricular valve repair remains a particular surgical challenge.

METHODS

We reviewed all surgical atrioventricular valve procedures in patients with univentricular heart and two separate atrioventricular valves who underwent surgical palliation. Endpoints of the study were reoperation-free survival and cumulative incidence of reoperation.

RESULTS

Between 1994 and 2021, 202 patients with univentricular heart and two separate atrioventricular valve morphology underwent surgical palliation, with 15.8% (32/202) requiring atrioventricular valve surgery. Primary diagnoses were double inlet left ventricle (n = 14, 43.8%), double outlet right ventricle (n = 7, 21.9%), and congenitally corrected transposition of the great arteries (n = 7, 21.9%). Median weight at valve surgery was 10.6 kg (interquartile range, 7.9-18.9). Isolated left or right atrioventricular valve surgery was required in nine (28.1%) and 22 patients (68.8%), respectively. Concomitant left and right atrioventricular valve surgery was performed in one patient (3.1%). Closure of the left valve was conducted in four patients (12.5%) and closure of the right valve in three (9.4%). Operative and late mortality were 3.1% and 9.7%, respectively. Reoperation-free survival and cumulative incidence of reoperation at 10 years after surgery were 62.3% (standard error of the mean: 6.9) and 30.9% (standard error of the mean: 9.6), respectively.

CONCLUSIONS

In patients with univentricular heart and two separate atrioventricular valves, surgical intervention on these valves is required in a minority of patients and is associated with low mortality but high incidence of reoperation.

Mechanical atrioventricular valve replacement in patients with single ventricle palliation

OBJECTIVES

Atrioventricular valve (AVV) replacements in patients with single-ventricle circulations pose significant surgical risks and are associated with high morbidity and mortality.

METHODS

From 1997 to 2021, 16 consecutive patients with functionally single-ventricle physiology underwent mechanical AVV replacement. Primary outcome was transplant-free survival. Secondary outcomes included major postoperative morbidity.

RESULTS

The median age of AVV replacement was 2 years old (interquartile range 0.6-3.8 years). All AVV replacements were performed with a St. Jude Medical mechanical valve, median 24 mm (range, 19-31mm). Extracorporeal membrane oxygenation (ECMO) was required in 4 patients. Operative mortality was 38% (6/16). There were 2 late deaths and 3 transplants. Transplant-free survival was 50% at 1 year, 37.5% at 5 years, and 22% at 10 years. Transplant-free survival was higher for patients with preserved ventricular function (P = 0.01). Difference in transplant-free survival at 1 year was 75% vs 25%, at 5 years was 62.5% vs 12.5% and at 10 years was 57% vs 0%. Three (19%) patients had complete heart block requiring permanent pacemaker insertion. 6 of 13 patients (46%) patients reached Fontan completion (3 patients operated at/after Fontan). Significant bleeding events occurred in 8 patients (50%) with 3 patients suffering major cerebrovascular accidents. There were 6 events of valve thrombosis in 5 patients, resulting in 2 deaths and 2 heart transplants.

CONCLUSIONS

Mechanical valve replacement carries significant morbidity and mortality risk. While it successfully salvages about half of patients with preserved ventricular function, careful consideration of alternative options should be made before embarking upon mechanical valve replacement.

Mechanical tricuspid valve replacement in hypoplastic left heart syndrome: An institutional experience

Objective

Atrioventricular valvar regurgitation in patients with single ventricles is associated with worse outcomes. Valve repair or replacement has been undertaken in an attempt to reduce mortality and morbidity. Current data on valve replacement in single ventricle patients are limited and derived from heterogenous populations. We describe our experience with repair and replacement of the tricuspid valve in children undergoing single ventricle palliation for hypoplastic left heart syndrome.

Methods

We included 27 patients with hypoplastic left heart syndrome with at least moderate tricuspid regurgitation who underwent valve intervention between 2007 and 2021 at our institution; charts were retrospectively reviewed for data.

Results

Eleven patients (73% male) underwent valve replacement (median age, 3 years). Preoperative ventricular systolic function was normal in 10 patients (91%). Median follow-up postoperatively was 4 years with no early mortality, 1 (9%) late mortality, and 1 heart transplant (9%). Morbidity consisted of complete heart block in 1 patient (9%), with no important hemorrhagic or thrombotic events. Among survivors of replacement (n = 9), ventricular function was preserved in all (n = 8) who had normal function preoperatively and improved in the remaining patient. Sixteen patients underwent valve repair (median age, 4 months) with no early mortality, 8 (50%) midterm mortalities, and 2 heart transplants (12%).

Conclusions

Tricuspid valve replacement is a feasible option in hypoplastic left heart syndrome with significant tricuspid regurgitation, with favorable outcomes in the intermediate follow-up. When undertaken in the setting of normal function, ventricular function may be preserved in up to 80% of patients. Long-term follow-up is needed.

Outcomes of the Surgical Management of Atrial Isomerism and Functional Single Ventricle: A Single-Centered Cohort From China

Objectives: The management of atrial isomerism with complex congenital heart disease remains challenging. Experience has been largely obtained in advanced countries. The clinical diversity is greater in China. We evaluated the early- and medium-term outcomes of surgical treatment of these patients. Methods: We reviewed 86 patients of atrial isomerism with complex congenital heart disease undergoing varied surgeries in our center in 2008-2020. Cox regression models were used to analyze the risk factors for mortality. Results: There were 75 cases of right and 11 of left atrial isomerism. Eighty-three (96.5%) patients underwent single-ventricle staged palliation approach, with 10 early and 7 late deaths. The overall 1-, 5-, and 10-year survival rates were 84.7, 79.3, and 79.3%, respectively. Thirty-six (43.4%) patients completed the Fontan procedure with median age of 48 months and freedom from death or Fontan failure at 1-, 5-, and 8-years were 94.4, 87.4, and 80.7%, respectively. Concomitant total anomalous pulmonary venous connection [hazard ratio (HR): 5.15 (1.95-12.94), p = 0.008], more than moderate atrioventricular valve regurgitation [HR: 4.82 (2.42-6.79), p = 0.003], and the need for first-stage palliative surgery [HR: 4.58 (1.64-10.76), p = 0.015] were independent risk factors for mortality. Conclusions: Despite even greater clinical diversity, the surgical outcomes of atrial isomerism with complex congenital heart disease are improving in China. The early and intermediate outcomes are comparable to many previous reports. Concomitant total anomalous pulmonary venous connection, moderate or severe atrioventricular valve regurgitation, and the need for a first-stage palliative surgery are still independent risk factors for mortality.

Long-Term Outcomes of Atrioventricular Valve Surgery in Patients with Functional Single Ventricle: Should We Avoid Valve Replacement?

Atrioventricular valve regurgitation (AVVR) is associated with increased morbidity and mortality in patients with single ventricle physiology. The purpose of this study was to evaluate the long-term results of the surgical management of AVVR and to analyze the effects of AV valve replacement. The medical records of 38 single ventricle patients who underwent atrioventricular valve surgery more than once between January 2001 and March 2018 were retrospectively reviewed. We analyzed and compared clinical data of patients who underwent valve replacement as an initial treatment (n = 8) for AVVR with patients who initially underwent valve repair (n = 30). The median follow-up duration was 98.1 months (range, 0.9-209.6 months). There was one early mortality and seven late mortalities. Freedom from reoperation between the two groups at 15 years of follow-up was significantly different: 18.3% in the repair group and 100% in the replacement group (p = 0.013). The replacement group showed a better overall survival rate (100%) at 15 years than the repair group (68.5%) without statistical significance (p = 0.097). All mortalities occurred in the repair group. Nine patients in the repair group (30%) and one patient in the replacement group (12.5%) showed preoperative ventricular dysfunction. RV-type single ventricle with atrioventricular (AV) valve annular dilatation was found out as a risk factor of AVV replacement both in univariate (p = 0.04) and multivariate (p = 0.004) analysis. AV valve replacement might be considered as a primary treatment option for patients who have an annular dilation with an RV-type single ventricle rather than repeated valvuloplasty.

Common atrioventricular valve surgery in children with functional single ventricle

OBJECTIVES

A common atrioventricular valve (CAVV) is considered to be a risk factor for early and late deaths in patients with functional single ventricle (FSV). CAVV surgery in patients with FSV is challenging and there is limited knowledge of the outcomes of CAVV repair with univentricular physiology.

METHODS

We reviewed all CAVV surgical procedures in patients with FSV who underwent univentricular palliation. End points of the study were survival after CAVV surgery and cumulative incidence of reoperation.

RESULTS

Between 1984 and 2019, 66 children with CAVV and FSV underwent single-ventricle palliation, of whom 45.5% (30/66) required CAVV surgery. Indication for surgery was moderate CAVV regurgitation in 40% (12/30) and severe CAVV regurgitation in 60% (18/30). CAVV repair was performed in 93.3% (28/30) and CAVV replacement in 6.7% (2/30). The median age and weight at surgery were 0.9 years (interquartile range 0.3-1.8) and 6.5 kg (interquartile range 3.9-8.7), respectively. Operative and late mortality were 23.3% and 8.7%, respectively. Survival and cumulative incidence of reoperation at 4 years after CAVV surgery were 68.9% [standard deviation (SD): 8.7] and 35.8% (SD: 9.1), respectively. Fontan completion was achieved in 60% (18/30). Survival at 4 years after birth was 69.7% (SD: 8.5) in 30 patients with CAVV surgery, whereas it was 83% (SD: 6.3) in 36 patients without CAVV surgery (P = 0.32).

CONCLUSIONS

CAVV surgery in patients with FSV is associated with substantial mortality and a high incidence of reoperation.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

BACKGROUND

The influence of ventricular morphology on Fontan outcomes is controversial.

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Valve Replacement in Children with Single Ventricle Physiology

Severe atrioventricular valve (AVV) or semilunar valve (SLV) regurgitation in the setting of a single ventricle physiology may proceed to valve replacement if repair strategies fail. Outcome data for these children are limited. We present transplant-free survival of a case series of children with single ventricle physiology undergoing either atrioventricular replacement (AVVR) or semilunar valve replacement (SLVR) from a multi-institutional, US-based registry (Pediatric Cardiac Care Consortium-PCCC). Outcomes were derived from PCCC and by linkage with the National Death Index (NDI) and Organ Procurement Transplant Network (OPTN). Fifty children with single ventricle physiology were identified to have received either AVVR (n = 38) or SLVR (n = 12). There were 17 in-hospital deaths including 8 intraoperative deaths (all intraoperative deaths were among children requiring AVVR). The in-hospital mortality was 42% and 8% for AVVR and SLVR, respectively. Among the 33 children surviving to hospital discharge, follow-up was available in 15 (46%). Death or cardiac transplant after hospital discharge occurred in 10-death in 4 (all among those requiring AVVR), cardiac transplant in 6 (2 following AVVR, 4 following SLVR). Valve replacement in children with single ventricle physiology, especially AVVR, is associated with poor outcomes. Alternative palliation strategies should be considered in children with single ventricle physiology with significant AVV or SLV regurgitations.

Postoperative heart failure after stage 1 palliative surgery for single ventricle cardiac disease

Outcomes for patients with single ventricle congenital heart disease (SV-CHD) continue to improve over time. However, the prognosis for patients who develop heart failure immediately after surgery is poorly understood. We conducted a single-center, retrospective cohort study of patients with SV-CHD, who suffered postoperative heart failure. Of 1038 cardiac surgeries performed on 621 SV-CHD patients between 2004 and 2010, 125 patients met inclusion criteria, including non-septatable anatomy, stage 1 surgery, and verified low cardiac output or heart failure state per STS definition. Overall survival was 73.2% at 2 months, 64.9% at 1 year, 60.5% at 2 years, and 54.6% at 4 years. Inotrope dependence beyond 7 days post-op yielded 45% 2-year survival versus 68% for those who weaned from inotropes within 7 days (p = 0.02). Atrioventricular valve regurgitation (AVVR) influenced survival, and patients who developed renal failure or required ECMO fared poorly, even when they survived their hospitalization. Patients with postoperative heart failure and low cardiac output syndrome constitute a high-risk population beyond the term of the initial hospitalization and have an overall mid-term survival of 55% at 4 years. Wean from inotropic therapy is not completely reassuring in this population, as they have ongoing elevated risk of cardiac failure and death in the medium term. Ventricular dysfunction, AVVR, renal failure, and need for ECMO are all important prognostic factors for mid-term mortality. Inotrope dependence for > 7 days has important implications reaching beyond the hospitalization.

Outcomes of Common Atrioventricular Valve Repair in Patients With Single-Ventricle Physiology - Indication, Timing and Repair Techniques

BACKGROUND

Common atrioventricular valve (CAVV) repair in patients with a single ventricle remains a great challenge and a refractory issue for pediatric cardiac surgeons.

METHODS AND RESULTS

From January 2007 to April 2018, 37 consecutive patients with a single ventricle who underwent CAVV repair were included in the study group. Patients were divided into 2 groups based on the repair technique: patients in Group A were treated using the bivalvation technique, and patients in Group B underwent conventional repair techniques; baseline data were similar between groups. The inhospital and follow-up mortality were 5.4% (2/37) and 11.4% (4/35), respectively. After a follow-up of 65.5±29.3 months, the estimated 1-, 5-, and 10-year overall survival rates were 94.6%, 83.4%, and 77.0%, respectively. The rates of freedom from CAVV failure were 94.3%, 72.7%, and 62.9% after 1, 5, and 10 years, respectively. In the multivariate analysis, the independent factors for CAVV repair failure were repair technique (P=0.004) and heterotaxy syndrome (P=0.003). A total of 30 patients (81.1%) completed total cavopulmonary connection (TCPC); 3 patients required re-intervention; 24 of 31 patients (77.4%) were in New York Heart Association classes II and I at the latest follow-up.

CONCLUSIONS

Outcomes of CAVV repair in patients palliated by single-ventricular surgery are acceptable. The bivalvation technique is a simple and effective technique.

Management of Tricuspid Regurgitation in Patients With Hypoplastic Left Heart Syndrome

Tricuspid valve (TV) performance is critical for palliation of hypoplastic left heart syndrome. We will review current TV repair techniques, outcomes, and novel approaches.

Early- and Middle-Term Surgical Outcomes in Patients with Heterotaxy Syndrome

Objectives: Heterotaxy syndrome is a recognized risk factor for surgical cardiac interventions. We evaluated the early- and middle-term results of a surgical intervention for patients with heterotaxy syndrome. Methods: A total of 42 patients with heterotaxy syndrome were enrolled (September 2008 to March 2015). Left and right atrial isomerism were identified in 26% (11 out of 42) and 74% of patients (31 out of 42), respectively. The median age of the patients at the time of surgery was 6.8 months (range: 5 days to 22.3 years). Biventricular repair was completed in 3 patients with left atrial isomerism. Seventeen out of 39 patients who were scheduled for single ventricular repair completed a modified Fontan procedure. Results: The hospital mortality rate was 4.7% (2 out of 42). Another 5 deaths occurred in the remaining survivors following hospital discharge with a follow-up duration of 45.8 ± 23.6 months (range: 13-111 months). The 1-year and 5-year survival rates were 88.1% (37/42) and 83.3% (35/42), respectively. Univariate analysis and multivariate analysis identified pulmonary venous obstruction and atrioventricular valve replacement as additional risk factors for mortality. Conclusions: Right ventricular bypass surgery remains the preferred palliative procedure for patients with heterotaxy syndrome. Based on the current results, the early- and middle-term outcomes are satisfactory.

Atrioventricular valve repair along with Fontan completion

Atrioventricular valve regurgitation is widely known as a risk factor for Fontan completion in patients with univentricular physiology. To date, indications and timing for atrioventricular valve repair remain unclear and different surgical techniques have been advocated. Since 2013, 50 consecutive patients underwent extracardiac Fontan completion in our institution. Atrioventricular valve repair, by avoiding the use of a prosthetic ring, was performed as a concomitant procedure in three of them, with excellent short-term results. Beating-heart repair was performed in one of the patients with hypoplastic left heart syndrome as the underlying disease. Valve repair when moderate or severe regurgitation is present may be performed at a low risk. Both the staged approach of atrioventricular valve repair followed by the Fontan as a separate operation and the combined approach of simultaneous atrioventricular valve repair and Fontan have a role in the management of these complex patients. We highlight the importance of the use of "easy and simple" surgical techniques for repairing the atrioventricular valve in order to provide a better life prognosis in Fontan patients.

Long-term outcomes of common atrioventricular valve plasty in patients with functional single ventricle

OBJECTIVES

Common atrioventricular valve (CAVV) regurgitation is widely known as a risk factor for mortality and Fontan completion in patients with functional single ventricle. Hence, we reviewed our surgical experience with CAVV plasty in Fontan candidates.

METHODS

Staged Fontan strategy and extracardiac total cavopulmonary connection as Fontan modification were our principal approaches in 1995. Since then, 38 consecutive Fontan candidates (21 males, median weight at operation was 7.0 kg and median age was 17 months old) underwent CAVV plasty. Right atrial isomerism was associated with 24 patients. The initial CAVV plasty was performed before inter-stage bidirectional Glenn (BDG) in 3 patients, at BDG in 23, before Fontan in 4 and during Fontan in 8. Since 1995, the modified Alfieri technique with a tailed, expanded, polytetrafluoroethylene tube as a bridging strip was the procedure for repair and 27 patients underwent the procedure. The mean follow-up period was 7.1 years (range 0-17 years).

RESULTS

Actuarial survival and freedom from CAVV replacement rates at 1, 5 and 10 years were 81, 70 and 67% and 89, 85 and 75%, respectively. Seven patients ultimately underwent CAVV replacement with one death. Twenty-three of the 38 patients completed Fontan operation (61%). Association with total anomalous pulmonary venous connection (P= 0.01) and CAVV plasty before BDG (P= 0.05) were risk factors for mortality.

CONCLUSIONS

CAVV plasty for patients with functional single ventricle is still challenging; however, the aggressive and repeated surgical intervention may contribute to provide better life-prognosis. The ventricular volume unloading effect of BDG without additional pulmonary blood flow or Fontan operation did not contribute to maintain CAVV function. Therefore, there would not be any hesitation for CAVV replacement to control CAVVR in the setting of systemic ventricular failure. Although the statistically significant therapeutic superiority of the modified Alfieri technique was not shown so far, further follow-up may reveal the advantage of this easy and simple technique.

Melody valve-in-ring procedure for mitral valve replacement: feasibility in four annuloplasty types

BACKGROUND

The recurrence of regurgitation after surgical mitral valve (MV) repair remains a significant clinical problem. Mitral annuloplasty rings are commonly used in MV repair procedures. The purpose of this study was to demonstrate the feasibility of transvenous valve-in-ring (VIR) implantation using the Melody valve (Medtronic, Minneapolis, MN), which is a valved-stent designed for percutaneous pulmonary valve replacement, and 4 distinct types of annuloplasty ring (AR) in an ovine model.

METHODS

Ten sheep underwent surgical MV annuloplasty ring placement (n=10): CE-Physio, Edwards Lifesciences, Irvine, CA [n=5]; partial ring [n=3]; flexible ring [n=1]; and saddle ring [n=1]). All animals underwent cardiac catheterization, hemodynamic assessment, and Melody VIR implantation through a transfemoral venous, transatrial septal approach 1 week after surgery. Follow-up hemodynamic, angiographic, and echocardiographic data were recorded.

RESULTS

Melody VIR implantation was technically successful in all but 1 animal. In this animal a 26-mm partial AR proved too large for secure anchoring of the Melody valve. In the remaining 9 animals, fluoroscopy showed the Melody devices securely positioned within the annuloplasty rings. Echocardiography revealed no perivalvular leak, and angiography revealed no left ventricular outflow tract obstruction, vigorous left ventricular function, and no aortic valve insufficiency. The median procedure time was 55.5 (range, 45 to 78) minutes.

CONCLUSIONS

This study demonstrates the feasibility of a purely percutaneous approach to MV replacement in patients with preexisting annuloplasty rings, regardless of ring type. This approach may be of particular benefit to patients with failed repair of ischemic mitral regurgitation.

Tricuspid valve repair in single ventricle: timing and techniques

Tricuspid valve performance in the systemic circulation is known to have important implications for survival and functional status after univentricular palliation of hypoplastic left heart syndrome (HLHS). Moderate to severe tricuspid valve regurgitation is not an uncommon finding in patients with HLHS undergoing staged surgical reconstruction. It can result from either abnormal valve morphology or incomplete leaflet coaptation, or both. But first and foremost, any aortic arch re-obstruction must be excluded. Development of significant tricuspid regurgitation (TR) remains an obstacle in improving survival after the Norwood procedure and likely compromised functional health after the Fontan procedure. Thus, surgical intervention for minimizing tricuspid valve deterioration and significant TR seems pivotal to improving long-term outcomes for patients with HLHS. This article provides an overview of the etiology and mechanisms of development of significant TR, natural history, indications for surgical intervention, and focuses on timing, techniques, and clinical outcomes of tricuspid valve repair in the setting of single ventricle.

Atrioventricular valve repair for patient with heterotaxy syndrome and a functional single ventricle

Heterotaxy syndrome is a mortality risk factor for patients with complex heart disease. These patients often have common atrioventricular valve (CAVV) morphology and significant atrioventricular valve regurgitation - yet another mortality risk factor in congenital heart disease. Thus, patients with both heterotaxy syndrome and atrioventricular valve regurgitation are at highest risk of mortality. A large number of patients with heterotaxy syndrome have CAVV and a functional single ventricle. These patients are more difficult to operate than patients with biventricular morphology because in the former, the CAVV is often less adapted to systemic afterload than the mitral valve. Herein, we present the results of atrioventricular valve repair surgeries performed at the Okayama University Hospital on patients with heterotaxy syndrome, atrial isomerism, and a functional single ventricle. In addition, we review the current literature in this typically challenging patient population. In-depth understanding of reasonable management strategies and resolution of technical issues will help guide surgeons during this procedure.

Atrioventricular valve repair in patients with functional single-ventricle physiology: impact of ventricular and valve function and morphology on survival and reintervention

OBJECTIVE

This study was to determine whether atrioventricular valve repair modifies natural history of single-ventricle patients with atrioventricular valve insufficiency and to identify factors predicting survival and reintervention.

METHODS

Fifty-seven (13.5%) of 422 single-ventricle patients underwent atrioventricular valve repair. Valve morphology, regurgitation mechanism, and ventricular morphology and function were analyzed for effect on survival, transplant, and reintervention with multivariate logistic and Cox regression models. Comparative analysis used case-matched controls.

RESULTS

Atrioventricular valve was tricuspid in 67% and common in 28%. Ventricular morphology was right in 83%. Regurgitation mechanisms were prolapse (n = 24, 46%), dysplasia (n = 18, 35%), annular dilatation (n = 8, 15%), and restriction or cleft (n = 2, 4%). Postrepair insufficiency was none or trivial in 14 (26%), mild in 33 (61%), and moderate in 7 (13%). Survival in repair group was lower than in matched controls (78.9% vs 92.7% at 1 year, 68.7% vs 90.6% at 3 years, P = .015). Patients with successful repair and normal ventricular function had equivalent survival to matched controls (P = .36). Independent predictors for death or transplant included increased indexed annular size (P = .05), increased cardiopulmonary bypass time (P = .04), and decreased postrepair ventricular function (P = .01). Ventricular dilation was a time-related factor for all events, including failed repair.

CONCLUSIONS

Survival was lower in single-ventricle patients operated on for atrioventricular valve insufficiency than in case-matched controls. Patients with little postoperative residual regurgitation and preserved ventricular function had equivalent survival to controls. Lower grade ventricular function and ventricular dilation correlated with death and repair failure, suggesting that timing of intervention may affect outcome.

Atrioventricular valve repair in patients with single-ventricle physiology: mechanisms, techniques of repair, and clinical outcomes

Significant atrioventricular (AV) valve insufficiency in patient with single ventricle-physiology is strongly associated with poor survival. Herein we discuss the etiology and mechanism of development of significant AV valve insufficiency in patients with single-ventricle physiology, surgical indication and repair techniques, and clinical outcomes along with our 10-year surgical experience. Our recent clinical series and literature review indicate that it is of prime importance to appreciate the high incidence and clinical effect of the structural abnormalities of AV valve. Valve repair at stage II palliation may minimize the period of volume overload, thereby potentially preserving post-repair ventricular function. Since 85% of the AV valve insufficiency was associated with structural abnormalities, inspection of an AV valve that has more than mild to moderate insufficiency is recommended because they are not likely to be successfully treated with volume unloading surgery alone.

Risk factors for adverse outcomes after surgery on the systemic atrioventricular valve in 109 children

In contrast to older patients, children and young adults rarely have isolated disease of the systemic atrioventricular valve. Stenosis and/or regurgitation of the systemic atrioventricular valve, however, frequently coexist with complex congenital cardiac disease. In addition, most patients undergoing surgery on the systemic atrioventricular valve have had previous intracardiac repairs.

Replacement of the common atrioventricular valve with floating annuloplasty in a patient with univentricular physiology

Significant common atrioventricular valve insufficiency is associated with increased mortality and morbidity in patients with univentricular physiology. Shortly after bidirectional cavopulmonary anastomosis and concomitant valvuloplasty, valve replacement was carried out using a floating annuloplasty technique reinforced by a Dacron strip in a patient with common atrioventricular valve insufficiency. The technique applied is described in detail.

Modified Fontan operation in patients with anomalies of systemic and pulmonary venous connection

The presence of anomalies of the systemic and pulmonary venous connection associated with single ventricle anomalies has been considered a contraindication for the Fontan operation (FO). The aim of this study is to outline the technical considerations associated with the presence of anomalies of systemic and/or pulmonary venous connections and to identify the risk factors for mortality in this group of patients undergoing the modified FO. Between 1989 and 2004, 63 patients (median age, 3.2 years) with anomalous systemic or pulmonary venous connection underwent a Fontan procedure at our institution. Nine patients had a combination of anomalous systemic and pulmonary venous connection, 49 patients had anomalous drainage only from the systemic circulation, and 5 patients had isolated anomalies of pulmonary venous return. Visceral heterotaxy syndrome was diagnosed in 25 patients. Previous palliative operations had been performed in 51 patients (81%). There was 1 early death, and 2 patients required take down of Fontan procedures. Two patients required reoperation for revision of the atrial baffle. At a mean follow-up of 4.6 +/- 3.4 years, there have been 5 late deaths (8%) and 45 patients (71%) have undergone Fontan completion. Actuarial survival was 92% at 1 year and 91% at 5 and 10 years-not significantly different from the overall survival of the Fontan patients. We conclude that the modified FO can be successfully performed in patients with anomalous systemic or pulmonary venous connections, including those with visceral heterotaxy syndrome, with morbidity and mortality rates that do not differ significantly from those achieved in all patients with normal connections.

Atrioventricular Valve Procedures with Repeat Fontan Operations: Influence of Valve Pathology, Ventricular Function, and Arrhythmias on Outcome

BACKGROUND

The purpose of this study is to analyze atrioventricular valve procedures when performed in association with repeat Fontan operations and to determine the influence of atrioventricular valvar pathology, ventricular function, and arrhythmias on outcome.

METHODS

Between December 1994 and August 2004, 80 patients had repeat Fontan operations that included arrhythmia surgery (78 of 80), venous pathway revision (78 of 80), atrioventricular valve repair-replacement (15 of 80), and other associated procedures. Mean ages were the following: at operation, 20.3 +/- 8.4 years; at prior Fontan, 7.1 +/- 5.8 years. Atrioventricular valve procedures were performed on 8 functionally mitral and 7 functionally tricuspid valves. The average cross-clamp and cardiopulmonary bypass times were 61.9 +/- 42.8 minutes and 218 +/- 82 minutes, respectively.

RESULTS

Ventricular dysfunction (8% vs 54%, p < 0.0001), valvar dysfunction (13% vs 25%, p < 0.05), and atrial arrhythmias (18% vs 86%, p < 0.0001) increased during the preceding 12.0 +/- 4.7 years before the most recent Fontan operation. Multivariate analysis for death, orthotopic cardiac transplantation (OCT), or renal dialysis showed severe ventricular dysfunction, age greater than 25 years, right or ambiguous functional ventricle, and ischemic time greater than 100 minutes to be highly significant. Notably, cardiac index, elevated end diastolic pressure, and atrial fibrillation were not predictors of outcome. Mitral valve repairs were inconsistent due to probable technical misjudgments; most tricuspid valves could not be repaired. Operative and late mortality were 1.2% and 5.0%, respectively. Emergent and late OCT were 1.2% and 3.7%, respectively.

CONCLUSIONS

Risk factors for poor outcome are severe ventricular dysfunction, right or ambiguous single ventricle, age greater than 25 years, and ischemic time greater than 100 minutes. Mitral valves are potentially more amenable to repair than are tricuspid valves. Prosthetic valve replacement should be considered when valve repair is questionable.