Reconstructive surgery in congenital mitral valve insufficiency (Carpentier's techniques): long-term results

The Fate of Mitral Valve Surgery in the Pediatric Age: A 25-Year Single-Center Experience

Background: The aim of this study was to evaluate the natural history of patients after mitral valve intervention in the pediatric age. Methods: This is a retrospective study including all patients who underwent mitral valve surgery from 1998 to 2022. The patients' surgical reports, postoperative records, and ambulatory visits were reviewed. The endpoints of the study were survival and freedom from mitral valve reoperation. Results: Of the 70 patients included in the cohort, 61 patients (86.7%) had congenital mitral valve disease, of whom 46 patients (75.4%) had a predominantly mitral regurgitation lesion, and 15 patients (24.6%) had a predominantly mitral stenosis. In the mitral regurgitation group, all of the patients underwent valve repair with an operative mortality of one patient (2.1%), and with median follow-up of 4 years (range, 0.5-13 years), there was 4.3% mortality (n = 2) and 71.2% freedom from reoperation. In the mitral stenosis group, 11 patients underwent mitral valve repair, and 4 patients underwent valve replacement. There was an operative mortality of two patients (13.3%). With a 2-year median follow-up (range: 0.1-23 years), there were no additional mortality cases in the mitral stenosis group. All three patients who survived primary mitral valve replacement (100%) and four patients who survived a primary repair (40.0%) underwent reoperation. Conclusions: This study demonstrates encouraging outcomes for mitral valve repair. The mortality of patients with congenital mitral valve disease may also be related to a difficult postoperative course, rather than the MV lesion itself.

Using DaSilva Cone Operation to Establish 1.5 or 2 Ventricle Circulation After Initial Single Ventricle Palliation with Starnes Procedure

Ebstein anomaly (EA) is a congenital dysplasia of the tricuspid valve resulting in reduced right ventricular (RV) volume and tricuspid regurgitation. Severe EA in the neonatal period is associated with high mortality. The Starnes procedure (fenestrated RV exclusion) is reserved for EA patients with cardiogenic shock and has previously committed patients to single ventricle (SV) palliation. In this report, we present the results of a strategy to redirect patients utilizing the Da Silva Cone operation to achieve a 2 or 1.5 ventricle circulation. Single-center retrospective study including all consecutive cases of Da Silva Cone operation after Starnes procedure. Between 2019 and 2023, six conversions from Starnes procedure to Cone reconstruction were performed. All were critically ill before their Starnes procedure; four on extracorporeal membrane oxygenation. Two patients were successfully rerouted to a two-ventricle repair; the remainder to 1.5 ventricle circulation. RV pressure estimates showed no correlation with success. Post-Cone intensive care and hospital stays were brief, median 5 and 6 days, respectively. All are between 2.5 and 6 years old, without indications for SV palliation. There were no deaths, with follow up ranging 1 month-4 years. No repeat interventions were performed on the tricuspid valves. One subject had a surgical pulmonary valve replacement. Tricuspid regurgitation was mild in all. The Da Silva Cone operation offers successful redirection of EA patients from a SV pathway to a 1.5 or 2 ventricle pathway after Starnes procedure. The approach is feasible and durable in midterm follow-up. The decision to initially proceed with Starnes need not be an irrevocable decision to continue down a SV palliation pathway.

Congenital Mitral Regurgitation Repair Based on Carpentier's Classification: Long-Term Outcomes

BACKGROUND

There are few reports of the outcomes of standardized surgical management addressing the etiologic and morphologic aspects of mitral valve malformation according to Carpentier's classification. This study aimed to evaluate the long-term outcomes of mitral valve repair in children according to Carpentier's classification.

METHODS

Patients who underwent mitral valve repair at our institution between 2000 and 2021 were retrospectively reviewed. Preoperative data, surgical techniques, and outcomes were analyzed according to Carpentier's classification. The proportion of patients free of mitral valve replacement and reoperation was estimated using Kaplan-Meier analysis.

RESULTS

Twenty-three patients (median operative age, four months) were followed up for 10 (range, 2-21) years. Preoperative mitral regurgitation was severe in 12 patients and moderate in 11 patients. Eight, five, seven, and three patients had Carpentier's type 1, 2, 3, and 4 lesions, respectively. Ventricular septal defect (N = 9) and double outlet of the great arteries from the right ventricle (N = 3) were the most commonly associated cardiac malformations. There were no cases of operative mortality or deaths during the follow-up. The overall five-year rate of freedom from mitral valve replacement was 91%, whereas the five-year rates of freedom from reoperation were 74%, 80%, 71%, and 67% in type 1, 2, 3, and 4 lesions, respectively. Postoperative mitral regurgitation at the last follow-up was moderate in three patients and less than mild in 20 patients.

CONCLUSIONS

Current surgical management of congenital mitral regurgitation is generally considered adequate; however, more complicated cases required a combination of various surgical techniques.

Valvular heart disease in congenital heart disease: a narrative review

Patients with congenital heart disease (CHD) are one of the fastest growing populations in cardiology, and valvular pathology is at the center of many congenital lesions. Derangements in valvular embryology lead to several anomalies prone to dysfunction, each with hemodynamic effects that require appropriate surveillance and management. Surgical innovation has provided new treatments that have improved survival in this population, though has also contributed to esotericism in patients who already have unique anatomic and physiologic considerations. Conduit and prosthesis durability are often monitored collaboratively with general and specialized congenital-focused cardiologists. As such, general cardiologists must become familiar with valvular disease with CHD for appropriate care and referral practices. In this review, we summarize the embryology of the semilunar and atrioventricular (AV) valves as a foundation for understanding the origins of valvular CHD and describe the mechanisms that account for heterogeneity in disease. We then highlight the categories of pathology from the simple (e.g., bicuspid aortic valve, isolated pulmonic stenosis) to the more complex (e.g., Ebstein's anomaly, AV valvular disease in single ventricle circulations) with details on natural history, diagnosis, and contemporary therapeutic approaches. Care for CHD patients requires collaborative effort between providers, both CHD-specialized and not, to achieve optimal patient outcomes.

Mitral valve repair with artificial chordae replacement in children: a single-center experience

OBJECTIVES

To summarize the experience of mitral valve (MV) repair with artificial chordae replacement in children, and analyze early and intermediate outcomes.

METHODS

From January 2011 to May 2019, all patients (< 18 years) who received MV repair with artificial chordae replacement were retrospectively reviewed. Freedom from MV reoperation, MV dysfunction, moderate or severe MR were estimated by the Kaplan-Meier curve and log-rank test.

RESULTS

A total of 30 patients were included in this study. According to our definition, 15 patients had simple lesions and 15 patients had complex lesions. During 36 months' follow-up (range 3-97 months), two patients received MV reoperation and seven patients developed MV dysfunction, including six patients with moderate or severe MR and one patient with mitral stenosis. Freedom from MV reoperation at 1, 5 and 8 years were 100%, 91.3% and 91.3%, respectively. And freedom from MV dysfunction at 1, 3 and 5 year were 96.0%, 77.1% and 61.8%, respectively. Five-year freedom from MV dysfunction showed significant differences between patients with simple lesions and patients with complex lesions (100% vs 32.7%, log-rank P = 0.008), and between patients aged less than 12 years and patients aged more than 12 year (33.5% vs 90.0%, log-rank P = 0.025).

CONCLUSION

The early and intermediate outcomes of mitral valve repair with artificial chordae replacement were acceptable in children, and the outcomes were optimal in patients with simple lesions, and patients aged more than 12 years.

Surgical repair of mitral valve bileaflet prolapse in pediatric patients

BACKGROUND

Pediatric mitral regurgitation (MR), especially with bileaflet prolapse, is relatively rare, of high complexity, and frequently associated with other congenital cardiac abnormalities. It remains a major therapeutic challenge for surgeons. This study reports our experience of surgical treatment of this mitral disease and midterm follow-up results.

METHODS

Between January 2016 and April 2020, nine pediatric patients, six females and three males, age ranged from 3 to 12 years (median age was 6 years) with a weight range of 12-36 kg (median weight was 25 kg), who all had over moderate regurgitation caused by bileaflet prolapse with mean distance of leaflet coaptation beyond annular plane 5.89 ± 1.66 mm (4-9 mm), received mitral valve (MV) repair. Various surgical techniques were used to repair MV.

RESULTS

The median follow-up period was 23(6-51) months, only one patient had moderately severe recurrent of MR, no patient developed systolic anterior motion (SAM) or mitral stenosis. Freedom from reoperation was 100% during the follow-up period. Compared to preoperation, the left atrial (LA) diameter and left ventricular end-diastolic diameter (LVEDD) decreased significantly from 2.94 ± 0.49 cm to 2.37 ± 0.38 cm (LA, p < .01) and from 4.13 ± 0.73 cm to 3.62 ± 0.49 cm (LVEDD, p < .01) respectively, ejection fraction (EF) decreased significantly (p < .05) from 68.56 ± 3.98% to 62.89 ± 4.48% before discharged.

CONCLUSION

We share our experience of surgical repair of mitral valve bileaflet prolapse in pediatric patients. Several surgical methods are considered to be used to repair the MV due to the high complexity of lesions. Anatomic correction or functional correction in our reports almost reaches the same result, while functional correction means simpler operation.

Isolated Congenital Mitral Regurgitation Repair in Children: Long-term Outcomes of Artificial Rings

BACKGROUND

Because isolated congenital mitral regurgitation (ICMR) is rare, the role of artificial rings in annuloplasty for ICMR is still debated. In this study we compared long-term results of annuloplasty with and without rings for ICMR.

METHODS

We performed a retrospective review of all patients ≤ 18 years old undergoing repair for ICMR from 1993 to 2019 at our hospital. Techniques of annuloplasty depended on individual lesions of the mitral valve (MV). One hundred twelve cases were divided into 3 groups: group A (43 cases) with ≥26-mm ring, group B (35 cases) with <26-mm ring, and group C (34 cases) with a band. Study endpoints were overall survival and MV reoperation.

RESULTS

Patients in group A were older than the others (median age 11 compared with 5 and 4 years, respectively). The MV lesions were complicated, but annular dilatation existed in 91% of cases. Three patients died, and there were 25 reoperations during a median follow-up period of 11 years. Groups B and C had higher rates of reoperation than group A (hazard ratios, 5.35 [95% confidence interval, 1.71-17.75] and 3.61 [95% confidence interval, 1.03-12.60], respectively). Most reoperations in group B (13/14 cases) were due to stenosis, whereas 6 of 7 reoperations in group C were due to recurrent regurgitation.

CONCLUSION

MV reconstruction for ICMR in children had good long-term survival. Annuloplasty with ≥26-mm ring had the lowest risk of reoperation. In cases of young children bands are more favored than <26-mm rings, but they carry a risk of recurrent regurgitation.

Mid-Term Results Comparing the Use of Artificial Chords Versus Native Chords for Mitral Valve Repair in Children

BACKGROUND

Our study is aimed at evaluating the mid-term surgical outcomes of mitral valve repair in children using various chordal reconstructive procedures (autologous in situ chords or artificial chords).

METHODS

A retrospective analysis of 154 patients who underwent mitral valve repair using various chordal reconstructive procedures from 1992 to 2012. Patients were divided into group A and group B based on use of artificial chords and autologous in situ chords, respectively, for the repair. There were 102 (66.2%) patients in group A and 52 (33.8%) patients in group B. The mean age at repair was 11.1 ± 4.5 years. Associated cardiac anomalies were found in 94 (61%) patients.

RESULTS

The median follow-up period was 4.2 years (Interquartile range: 2.0-9.9). There were two (1.3%) early deaths and five (3.2%) late deaths. There was no significant difference in survival at 15 years between the two groups (group A: 91.8% vs group B: 95.1%; P = .66). There was no significant difference in the freedom from reoperation at 15 years between group A (79.4%) and group B (97.2%; P = .06). However, there was significant difference in freedom from valve failure between group A (56.5%) and group B (74.1%; P = .03). Carpentier functional class III and postoperative residual mitral regurgitation (2+ MR, ie, mild-moderate MR) were the risk factors for valve failure.

CONCLUSIONS

Severity of the disease and its progression has profound effect on the valve repair than the technique itself. Both chordal reconstructive procedures can be used to produce satisfactory results in children.

Familial Mitral Arcade, Tricuspid Dysplasia, Left Ventricular Noncompaction and Short-Chain Acyl-CoA Reductase Deficiency

Mitral arcade is a rare entity that is mostly reported in pediatric patients. We present the first 2 adult cases of mitral arcade in combination with tricuspid dysplasia, left ventricular noncompaction, and short-chain acyl-CoA deficiency in 2 brothers. We examined clinical and echocardiographic data on 2 brothers with a combination of short-chain acyl-CoA deficiency, mitral arcade, tricuspid dysplasia, and left ventricular noncompaction (LVNC), highlighting their clinical course and outcomes. Two-dimensional and 3-dimensional transthoracic echocardiography revealed direct attachment of the papillary muscles to the mitral leaflets, namely mitral arcade, as well as mild mitral regurgitation along with LVNC and tricuspid dysplasia. Over the past 7 years, both brothers have remained asymptomatic with excellent exercise capacity (13 and 10 metabolic equivalents (METS), respectively). Mitral and tricuspid regurgitation remain mild with unchanged left ventricular function (ejection fraction: 65% and 59%). In conclusion, we highlight 2 cases with a constellation of pathology including short-chain acyl-CoA deficiency, mitral arcade, tricuspid dysplasia, and LVNC, which has never been described before.

Mitral Valve Surgery in the First Year of Life

Data are limited on outcomes associated with mitral valve surgery in infants. Prior studies report high mortality and increased risk for late cardiac failure particularly for those with mitral stenosis. We sought to evaluate outcomes in patients with mitral stenosis (MS) or regurgitation (MR) who had mitral valvuloplasty or replacement in the first year of life. A retrospective analysis of all patients in a single institution who underwent mitral valvuloplasty or replacement in their first year of life from 2004 to 2016 (n = 25), excluding patients with single ventricle pathology or those undergoing surgery for atrioventricular canal defect, was carried out. Median age and weight at surgery were 76.5 days (range 2-329) and 4.5 kg (range 3.0-10.1), respectively. The primary mitral pathology was MR in 16 and MS in 9 patients. Median follow-up among living patients was 4 years (range 106 days-12.3 years). Overall survival was 96% at 30 days and 87.8% at 1, 5, and 10 years. There were three early deaths (12%), all within 6 weeks of surgery. There were no late deaths. Three patients required valve replacement, 1 of which had a primary mitral valve replacement and died within 30 days of surgery. Re-intervention-free survival (surgical and catheter based) was 83.8%, 73.3%, and 48.9% at 1, 5, and 10 years per Kaplan-Meier estimates. There was no difference in re-intervention-free survival between patients with MR versus MS. No risk factors for death or re-intervention were identified. Mitral valvuloplasty and replacement can be performed in infants under 1 year of age with acceptable survival and need for re-intervention.

Posterior mitral leaflet extension using autologous pericardium to repair a hammock mitral valve associated with severe mitral valve regurgitation in a 4-month-old boy

We successfully repaired a hammock mitral valve associated with severe mitral valve regurgitation in a 4-month-old boy using posterior leaflet extension along with glutaraldehyde-treated autologous pericardium and the splitting of bilateral papillary muscles. Surgical reinterventions were performed for the bilateral papillary muscles at 14 and 24 months postoperatively. The extended autologous pericardium was still pliable with mild mitral valve regurgitation at 26 months postoperatively.

Outcome for Conservative Surgery for the Correction of Severe Mitral Valve Regurgitation in Children: A Single-Center Experience

Evolving reconstructive techniques have progressively become the preferred approach for treatment of pediatric mitral valve regurgitation. We present our experience in a cohort of patients undergoing surgical correction for severe mitral regurgitation. Fifty-five patients (age 1 month-18 years; median 5 years) were included in the present analysis. Different surgical techniques were used (posterior leaflet augmentation in 25, isolated cleft closure in 12, Alfieri-type procedure in 10, annuloplasty in 5, with artificial chordae in 2, and quadrangular resection with chordal transposition in 1). Follow-up time ranged from 1 to 192 months (median 38[IQR 12-54] months). Operative and follow-up mortality was 0%. Reintervention in the whole population occurred in 31% of patients. However, when first surgery was performed under 2 years of age (no = 17), reintervention reached nearly 50%. The degree of residual mitral regurgitation at follow-up remained stable after surgery, while a significant increase in mean transmitral gradient was observed over time (paired t test = 0.03). In multivariable Cox-regression analysis, post-surgical transmitral gradient was the only independent predictor for reintervention (p = 0.017; HR 2.4; 95%CI 1.2-5.1), after correcting for differences in age at surgery, type of reintervention, mitral annulus dimension, and BSA at the first surgery. ROC curve demonstrated that a post-surgical transmitral mean gradient value > 5 mmHg, was predictive for reintervention (AUC = 0.89; Youden index = 0.44). Our study suggests that the use of conservative technique strategy achieves satisfactory functional results in infants and children with severe MR, although the rate of reoperation in younger patients remains substantial. Post-operative moderate mitral stenosis was the strongest predictor for reoperation.

Outcomes of mitral valve replacement with bileaflet mechanical prosthetic valve in children

OBJECTIVES

We examined the outcomes following mitral valve replacement with bileaflet mechanical prosthetic valve in children and identified the predictors for mortality and reoperation.

METHODS

Medical records from 49 children who underwent mitral valve replacement between 1982 and 2015 were reviewed retrospectively. Median age and body weight at initial mitral valve replacement were 2.4 years and 9.7 kg, respectively. The median follow-up was 13 years. Surgical results and predictors for mortality and reoperation were investigated.

RESULTS

There was no operative mortality; eight late deaths occurred. The actuarial survival rates were 89.5%, 84.2%, and 80.7% at 5, 10, and 15 years, respectively, after initial mitral valve replacement. The actuarial freedom rates from related complications were 89.5%, 78.3%, and 70.7% at 5, 10, and 15 years, respectively. Nineteen patients required 1st re-mitral valve replacement at a median of 5.9 years; six of these 19 required 2nd re-mitral valve replacement at a median of 8.9 years after 1st re-MVR. The actuarial freedom rates from re-mitral valve replacement were 86.0%, 56.8%, and 44.2% at 5, 10, and 15 years, respectively. No predictor for death was determined; however, the predictor for re-mitral valve replacement was initial valve diameter less than 19 mm.

CONCLUSIONS

Survival outcomes among children after mitral valve replacement with bileaflet mechanical prosthetic valve in biventricular heart were satisfactory. However, complications, including re-mitral valve replacement, were frequent and the predictor was of a small prosthesis size.

Pre-intervention morphologic and functional echocardiographic characteristics of neonates with critical left heart obstruction: a Congenital Heart Surgeons Society (CHSS) inception cohort study

AIMS

The aims of this study were to provide a detailed descriptive analysis of pre-intervention morphologic and functional echocardiographic parameters in a large, unselected, multicentre cohort of neonates diagnosed with critical left heart obstruction and to compare echocardiographic features between the different subtypes of left-sided lesions.

METHODS AND RESULTS

Pre-intervention echocardiograms for 651 patients from 19 Congenital Heart Surgeons' Society (CHSS) institutions were reviewed in a core lab according to a standardized protocol including >150 morphologic and functional variables. The four most common subtypes of lesions were: aortic atresia (AA)/mitral atresia (MA) (29% of patients), AA/mitral stenosis (MS) (20%), aortic stenosis (AS)/MS (26%), and isolated AS (iAS) (18%). Only 17% of patients with AS/MS had an apex-forming left ventricle, compared with 0% of those with AA/MA and AA/MS (P < 0.0001). Aortic arch hypoplasia and coarctation were common across all four groups, while those with AA/MA and AA/MS had the smallest ascending aorta diameters. Flow in the ascending aorta was retrograde in 43% and 10% of the patients with AS/MS and iAS, respectively. The right ventricle was apex forming in 100% of patients with AA/MA and AA/MS, 96% with AS/MS and 70% with iAS (P < 0.0001). Moderate to severe tricuspid regurgitation was present in 13% of all patients.

CONCLUSION

This large multi-institutional study generates insight into the distribution of the functional and morphologic spectrum in patients with critical left-sided heart disease and identifies differences in these functional and morphologic characteristics between the main anatomic subtypes of critical left heart obstruction.

Valvular Regurgitation in a Biventricular Mock Circulatory Loop

Aortic regurgitation (AR), mitral regurgitation (MR), and tricuspid regurgitation (TR) after continuous-flow left ventricular assist device (LVAD) are common and may increase with prolonged LVAD support. The aim of this study was to simulate severe valvular regurgitation (AR, MR, and TR) within a 4-elemental pulsatile mock circulatory loop (MCL) and observe their impact on isolated LVAD and biventricular assist device (BiVAD) with HeartWare HVAD. Aortic regurgitation, MR, and TR were achieved via the removal of one leaflet from bileaflet mechanical valve from the appropriate valves of the left or right ventricles. The impact of alteration of LVAD pump speed (LVAD 2200-4000 RPM, right ventricular assist device [RVAD] 2400 RPM) and altered LVAD preload (10-25 mm Hg) was assessed. With each of the regurgitant valve lesions, there was a decrease in isolated LVAD pump flow pulsatility. Isolated LVAD provided sufficient support in the setting of severe MR or TR compared with control, and flows were enhanced with BiVAD support. In severe AR, there was no benefit of BiVAD support over isolated LVAD, and actual loop flows remained low. High LVAD flows combined with low RVAD flows and dampened aortic pressures are good indicators of AR. The 4-elemental MCL successfully simulated several control and abnormal valvular conditions using various pump speeds. Current findings are consistent with conservative management of MR and TR in the setting of mechanical support, but emphasize the importance of the correction of AR.

Technical performance scores are predictors of midterm mortality and reinterventions following congenital mitral valve repair

OBJECTIVES

The Technical Performance Score (TPS) has been shown to be predictive of postoperative mortality, morbidities and reinterventions following various cardiac procedures in children. We hypothesized that TPS is also a predictor of mitral valve repair outcomes.

METHODS

A review of patients who underwent mitral valve repair from January 2000 to December 2013 was performed. Primary repair of complete atrioventricular defect was excluded. The scores were determined according to previously published criteria based on the need for reintervention and predischarge echocardiograms: Class 1 (no residua), Class 2 (minor residua) or Class 3 (pacemaker implantation, major residua or reintervention for major residua prior to discharge). Cox proportional hazard models and Kaplan-Meier estimator were used.

RESULTS

A total of 587 patients underwent mitral repair (median age 2.6 years). Median follow-up duration was 3 years. There were 125 (21.3%) post-discharge mitral reinterventions and freedom from reintervention was 85.2%, 78.2% and 69.4% at 1, 2 and 5 years, respectively. Both TPS Class 2 [hazard ratio (HR) 3.6, 95% confidence interval (CI) 1.4-10.0; P  = 0.02] and Class 3 (HR 8.7, 95% CI 3.0-25.1; P  < 0.001) were associated with post-discharge reinterventions. There were 31 late deaths/transplantations, and transplant-free survival at 1, 2 and 5 years was 97.8%, 95.3% and 93.2%. TPS 3 was associated with decreased post-discharge transplant-free survival (HR 5.5, 95% CI 1.2-25.0; P  = 0.03). Post-discharge mitral reintervention was not associated with increased mortality.

CONCLUSIONS

The TPS is a strong predictor of midterm mortality and post-discharge mitral reintervention in congenital patients who underwent mitral repair.

Repair Techniques for Mitral Valve Insufficiency in Children

Congenital mitral valve (MV) dysplasia is a relatively rare and highly complex cardiac disease. We sought to provide a comprehensive analysis of the current surgical techniques for treating mitral valve insufficiency and the results of mitral valve repair at our institution. Between 1972 and 2017, 104 consecutive patients underwent surgical repair of congenital MV dysplasia-insufficiency at our institution. Among these, 59 patients presented with MV insufficiency (or prevalent MV insufficiency) and were part of the study. There was 1 early (1.7%) and 1 late death (1.7%). Survival at 5, 10 and 20 years was 98%, 98% and 94%, respectively. Eight patients (14%) required MV replacement for residual significant MV insufficiency. Freedom from re-intervention for MV dysfunction at 5, 10 and 20 years were 89%, 84% and 79%, respectively. Surgical techniques for treating mitral valve insufficiency must be tailored for each patient with the main goal of achieving a proper valve function, rather than a "normal" anatomy. The mechanism underlying valve dysfunction in congenital mitral valve insufficiency is multifactorial and requires the application of a variety of surgical techniques in each case.

The Mid-term Results of Mitral Valve Repair for Isolated Mitral Regurgitation in Infancy and Childhood

The objective of this study was to assess the mid-term results of mitral valve (MV) repair in infancy and childhood with isolated mitral regurgitation (MR). From January 2005 to January 2016, 40 consecutive patients with isolated MR underwent MV repair in Fuwai Hospital, Beijing, China. Patients' clinical data were analyzed retrospectively. Mean age at operation was 13 ± 5 (6-24) months and 22 patients (55%) were younger than 1 year. Mean weight at operation was 8.5 ± 1.9 (4.2-13) kg and 34 patients (85%) were lighter than 10 kg. All patients presented moderate or greater MR. After MV repair, all patients had mild MR or none, while two patients underwent re-repair immediately when TEE showed moderate MR. Mean left atrial diameter decreased from 28.0 ± 6.5 to 20.7 ± 4.8 mm and mean left ventricular end-diastolic diameter decreased from 38.6 ± 7.0 to 30.2 ± 4.9 mm (p < 0.001 for both). There was no early death. Clinical follow-up was conducted in 37 patients over an average period of 49 ± 31 (20-134) months. Follow-up echocardiography showed that one patient had severe MR who underwent redo repair 14 months after operation, one patient had moderate to severe MR, and three patients had moderate MR. Overall freedom from moderate or greater MR was 96.3 ± 3.6%, 91.9 ± 5.5%, and 83.6 ± 9.4% at 2, 5, and 10 years, respectively. The early and mid-term results of MV repair in pediatric patients with isolated MR were satisfactory. In majority of patients, less complex surgical repair techniques were utilized, namely annuloplasty or commissuroplasty. The combination of various repair methods in complex patients could achieve excellent outcome.

A Growth-Accommodating Implant for Paediatric Applications

Medical implants of fixed size cannot accommodate normal tissue growth in children, and often require eventual replacement or in some cases removal, leading to repeated interventions, increased complication rates and worse outcomes. Implants that can correct anatomic deformities and accommodate tissue growth remain an unmet need. Here, we report the design and use of a growth-accommodating device for paediatric applications that consists of a biodegradable core and a tubular braided sleeve, with inversely related sleeve length and diameter. The biodegradable core constrains the diameter of the sleeve, and gradual core degradation following implantation enables sleeve and overall device elongation in order to accommodate tissue growth. By using mathematical modeling and ex vivo experiments using harvested swine hearts, we demonstrate the predictability and tunability of the behavior of the device for disease- and patient-specific needs. We also used the rat tibia and the piglet heart valve as two models of tissue growth to demonstrate that polymer degradation enables device expansion and growth accommodation in vivo.

Current Interventional and Surgical Management of Congenital Heart Disease: Specific Focus on Valvular Disease and Cardiac Arrhythmias

Successful outcome in the care of patients with congenital heart disease depends on a comprehensive multidisciplinary team. Surgery is offered for almost every heart defect, despite complexity. Early mortality for cardiac surgery in the neonatal period is ≈10% and beyond infancy is <5%, with 90% to 95% of patients surviving with a good quality of life into the adult years. Advances in imaging have facilitated accurate diagnosis and planning of interventions and surgical procedures. Similarly, advances in the perioperative medical management of patients, particularly with intensive care, has also contributed to improving outcomes. Arrhythmias and heart failure are the most common late complications for the majority of defects, and reoperation for valvar problems is common. Lifelong surveillance for monitoring of recurrent or residual structural heart defects, as well as periodic assessment of cardiac function and arrhythmia monitoring, is essential for all patients. The field of congenital heart surgery is poised to incorporate new innovations such as bioengineered cells and scaffolds that will iteratively move toward bioengineered patches, conduits, valves, and even whole organs.

Outcomes of Totally Endoscopic Atrial Septal Defect Closure Using a Glutaraldehyde-Treated Autologous Pericardial Patch

BACKGROUND

We evaluated the outcomes of totally endoscopic minimally invasive surgery for atrial septal defect (ASD) using a glutaraldehyde-treated autologous pericardial patch in the transcatheter interventional era.Methods and Results:We retrospectively reviewed 37 consecutive patients who underwent totally endoscopic ASD closure with a glutaraldehyde-treated autologous pericardial patch between June 2011 and April 2015. All patients had been deferred from catheter-based intervention for clinical or anatomical reasons. We analyzed operative outcomes and postoperative echocardiographic data. The mean age was 45.7±16.5 years, and 25 patients (67.6%) were women. The mean ratio of pulmonary to systemic flow was 2.4±0.7. Six patients (16.2%) underwent concomitant tricuspid valve repair, and 3 patients (8.1%) underwent concomitant atrial fibrillation surgery. There were no operative deaths, and the median length of hospital stay was 5 days. Postoperative echocardiography revealed trivial residual shunt in 1 patient. During the follow-up period, there were no re-interventions for ASD or readmission for heart failure. Follow-up echocardiography revealed no recurrent shunt or calcification of the autologous pericardial patch.

CONCLUSIONS

Totally endoscopic ASD closure with a glutaraldehyde-treated autologous pericardial patch demonstrated excellent outcomes. It is a useful option for patients with unfavorable anatomy or other reasons excluding transcatheter intervention.

Palliative Mitral Valve Repair During Infancy for Neonatal Marfan Syndrome

An infant with neonatal Marfan syndrome (nMFS), a condition that is nearly always lethal during infancy, was referred to our hospital with symptoms of congestive heart failure resulting from severe mitral valve insufficiency. During mitral valve repair, the use of an annuloplasty ring was waived until annular dilatation was achieved after 2 palliative mitral valvuloplasty procedures. After the definitive operation, the patient's mitral valve function remained within normal limits until the last follow-up when the patient was 11 years old. To the best of our knowledge, this patient has the longest recorded survival after mitral valve repair.

The early and mid-term results of mitral valve repair for mitral regurgitation in children

PURPOSE

To review the surgical techniques and mid-term results of mitral valve repair in children with moderate or severe mitral regurgitation (MR).

METHODS

One hundred and seven children with moderate or severe MR, aged 19.6 ± 8.5 months, were enrolled in this study. The surgical techniques used for mitral valve repair varied according to the mitral valve morphology, and included annuloplasty, annuloplasty ring, cleft closure, reconstruction of the posterior leaflet, etc. The concomitant cardiac anomalies were treated simultaneously. The results of repair were evaluated by transesophageal echocardiography performed during the operation and by serial transthoracic echocardiography performed during the follow-up.

RESULTS

One hundred and six cases had no more than mild regurgitation intraoperatively, whereas only one case had moderate regurgitation. This patient underwent redo repair immediately, and the subsequent regurgitation was trivial. The in-hospital mortality rate was 0.9 % (1/107). The average follow-up was 46.5 ± 8.2 months. One patient died of heart failure 10 months postoperatively. The freedom from moderate or severe regurgitation after mitral valve repair was 92.3 ± 3.3 %.

CONCLUSION

Pediatric patients with moderate or severe MR require early surgical treatment. The early and mid-term results of mitral valve repair in pediatric patients were satisfactory.

Nitric oxide synthase-3 promotes embryonic development of atrioventricular valves

Nitric oxide synthase-3 (NOS3) has recently been shown to promote endothelial-to-mesenchymal transition (EndMT) in the developing atrioventricular (AV) canal. The present study was aimed to investigate the role of NOS3 in embryonic development of AV valves. We hypothesized that NOS3 promotes embryonic development of AV valves via EndMT. To test this hypothesis, morphological and functional analysis of AV valves were performed in wild-type (WT) and NOS3^−/− mice at postnatal day 0. Our data show that the overall size and length of mitral and tricuspid valves were decreased in NOS3^−/− compared with WT mice. Echocardiographic assessment showed significant regurgitation of mitral and tricuspid valves during systole in NOS3^−/− mice. These phenotypes were all rescued by cardiac specific NOS3 overexpression. To assess EndMT, immunostaining of Snail1 was performed in the embryonic heart. Both total mesenchymal and Snail1⁺ cells in the AV cushion were decreased in NOS3^−/− compared with WT mice at E10.5 and E12.5, which was completely restored by cardiac specific NOS3 overexpression. In cultured embryonic hearts, NOS3 promoted transforming growth factor (TGFβ), bone morphogenetic protein (BMP2) and Snail1expression through cGMP. Furthermore, mesenchymal cell formation and migration from cultured AV cushion explants were decreased in the NOS3^−/− compared with WT mice. We conclude that NOS3 promotes AV valve formation during embryonic heart development and deficiency in NOS3 results in AV valve insufficiency.

Idiopathic isolated annular dilatation causing congenital mitral regurgitation

Isolated annular dilatation is an extremely uncommon cause of congenital mitral regurgitation. We report a case of a 5-year-old child with idiopathic isolated annular dilatation causing severe congenital mitral regurgitation.

Mitral valve replacement using mechanical prostheses in children: early and long-term outcomes

Compared with mitral repair, mitral valve replacement is an uncommon procedure in children due to associated high mortality and morbidity rates. The present study investigated early and late outcomes after MVR with mechanical prostheses in children at our institution. Between January 1994 and December 2009, 19 children underwent MVR. Mean patient age was 7.6 ± 5.5 years (range 3 months-16 years), and mean body weight was 23.7 ± 15.1 kg (range 5.0-58.1 kg). Mean prosthesis size was 25.8 ± 4.2 mm (range 19-31 mm). There were no operative or late mortalities. Three patients showed decreased left-ventricular function before surgery, and one of them underwent successful heart transplantation due to progressive LV dysfunction at 10 months after MVR. The proportion of patients with freedom from reoperation at 10 years was 94.7 ± 5%. There were no major thromboembolic or bleeding episodes. Although the small number of patients in our study was a limitation, MVR in children was found to result in excellent early and long-term outcomes. It appears that MVR could be considered in children before LV dysfunction develops.

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.

Congenital Mitral Valve Regurgitation in Adult Patients

Objective: Congenital mitral valve regurgitation (MVR) is a rare disease found in adults. We report on our 5-year surgical experience with congenital MVR in adults.Methods: We reviewed the data for 48 consecutive patients (26 men), aged >18 years (median, 42 years; range, 18-78 years) who underwent operations for severe congenital MVR between June 2005 and May 2010. Patients with atrioventricular septal defect were excluded.Results: Congenital MVR was preoperatively diagnosed in 28 cases (58%). The lesions consisted of annular dilation (100%), valvular cleft (58%), prolapsed leaflet (40%), papillary muscle abnormality (5%), commissure fusion (2%), and leaflet deficiency (2%). Mitral valve repair was performed in 42 cases (88%) by means of Carpentier techniques. The other 6 patients underwent mitral valve replacement; one of these patients died of ventricular fibrillation 2 days after surgery. There were no other hospital deaths or late mortality. At the last follow-up (median, 38 months; range, 2-50 months), all 47 patients were in New York Heart Association functional class I or II. Echocardiography evaluations for the 42 patients who underwent the repairs revealed that 32 (76%) of the patients had no or trivial MVR and 10 patients (24%) had mild MVR. No patient underwent reoperation.Conclusion: Congenital MVR is rare and often misdiagnosed in adults. Mitral valve repair is feasible in the majority of patients, with excellent immediate and medium-term results.

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.

Isolated congenital mitral valve regurgitation presenting in the first year of life

AIM

Isolated congenital mitral regurgitation is rare and, when presenting in infancy, reflects severity of the malformation. The natural history is often fatal, and management during the first year of life remains a therapeutic challenge. These infants are poorly understood largely because of an absence of reporting in the medical literature and limited experience in each institution. We reviewed our own experience in order to add to the understanding of this condition.

METHODS

A retrospective review was performed on seven infants with significant isolated congenital mitral regurgitation. An associated patent ductus arteriosus was present in two. Mean age at referral was 17.7 weeks (1 day to 47 weeks) and mean weight was 6.8 kg (3.7-12.5 kg).

RESULTS

Two infants were managed conservatively, and one underwent surgical ligation of a patent ductus arteriosus. Following spontaneous and surgical duct closure, no further intervention was required in two infants. The remaining four infants underwent three valve repairs and three valve replacements. The in-hospital mortality was 29%, occurring in those under 1 year of age undergoing emergency valve surgery. Two reoperations followed mitral valve repair in the first year of life. No significant complications or late deaths occurred.

CONCLUSIONS

Our experience suggests closure of a patent ductus arteriosus should be undertaken prior to mitral valve surgery. There may be a poorer prognosis in those under one year of age requiring emergency mitral valve surgery. Those who can be managed conservatively or undergo mitral valve surgery as an elective procedure tend to have a better outcome.

Edge-to-edge technique: is it also useful in children?

OBJECTIVE

Mitral valve prolapse is a rare condition and represents a challenge for cardiac surgeons. Many techniques have been described to treat the wide spectrum of abnormalities causing mitral valve regurgitation but the low incidence of these abnormalities is the cause of the relatively poor experience of many institutions.

METHODS

From April 2005 to September 2006, five patients underwent isolated mitral valve repair with the edge-to-edge technique for anterior or bileaflet prolapse. Three patients also had a Gore-Tex strip to reinforce the posterior annulus, whereas two had a 26-size soft incomplete ring annuloplasty.

RESULTS

There was no death and none of the patients required reoperation. None of the patients had mitral regurgitation more than 1+ at a mean follow-up of 30 months. None of the patients had mitral stenosis or any valve-related event.

CONCLUSION

The edge-to-edge technique is a well tolerated and useful technique for the anterior or bileaflet prolapse of the mitral valve. Although many techniques have been described with good results, in many anatomical settings and in small patients, edge-to-edge is a good option and might not interfere with the growth of the valve. Early results are encouraging but a longer follow-up is needed to evaluate the long-term prognosis.