Aortic valve repair by cusp extension for rheumatic aortic insufficiency in children: Long-term results and impact of extension material

Trileaflet pulmonary valve reconstruction with the Ozaki technique in an adult patient of tetralogy of Fallot with absent pulmonary valve

Pulmonary valve interventions are one of the most common cardiac interventions that are being performed in patients with a wide variety of congenital heart diseases, more so in adults with congenital heart disease. Despite the introduction of various different reconstructive techniques and conduits, the ideal option still remains elusive. Lack of growth and re-operation for conduit replacement remains an Achilles heel in such conduits. So, surgeons have constantly tried to evolve surgical techniques that would obviate their use and allow age-related growth. The Ozaki procedure has proven to be technically reproducible and have excellent mid-term results in the aortic position in adults. Extending the same principle for reconstruction of the pulmonary valve can prove to be a reasonable alternative.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12055-022-01469-1.

Surgical Management of Complex Aortic Valve Disease in Young Adults: Repair, Replacement, and Future Alternatives

The ideal aortic valve substitute in young adults remains unknown. Prosthetic valves are associated with a suboptimal survival and carry a significant risk of valve-related complications in young patients, mainly reinterventions with tissue valves and, thromboembolic events and major bleeding with mechanical prostheses. The Ross procedure is the only substitute that restores a survival curve similar to that of a matched general population, and permits a normal life without functional limitations. Though the risk of reintervention is the Achilles' heel of this procedure, it is very low in patients with aortic stenosis and can be mitigated in patients with aortic regurgitation by tailored surgical techniques. Finally, the Ozaki procedure and the transcatheter aortic valve implantation are seen by many as future alternatives but lack evidence and long-term follow-up in this specific patient population.

Surgical Repair of a Sinus of Valsalva Aneurysm

A surgically challenging case of an unruptured Sinus of Valsalva aneurysm (SoVA) with severe aortic regurgitation (AR) due to cusp prolapse is presented. Sinus reconstruction with a patch cut out from the sinus portion of a Gelweave Valsalva graft (Terumo Vascutek) was performed. Intraoperative measurements showed insufficient effective height of the right coronary cusp; therefore, cusp plication and pericardial patch augmentation of the right coronary cusp were performed with satisfying result.

Aortic valve repair for the treatment of rheumatic aortic valve disease: a systematic review and meta-analysis

Valvuloplasty for rheumatic aortic valve disease remains controversial. We conducted this study to explore whether aortic valvuloplasty is appropriate for the rheumatic population. A comprehensive search was conducted, and 7 eligible retrospective studies were identified from PubMed, Embase, Medline and Cochrane (up to April 7, 2020) according to the inclusion and exclusion criteria. The data for hospital mortality, 5-year survival, 5-year reoperation, aortic insufficiency grade (AIG) and aortic valve gradient (AVG) were extracted by 2 independent reviewers and were analysed to evaluate the safety and availability of aortic valvuloplasty for rheumatic patients. The heterogeneity of the results was estimated using the Q test and I² statistics. The fixed pooling model was used when I² ≤ 50%; otherwise, the random pooling model was selected. 7 articles with 418 patients were included. The pooled hospital mortality, 5-year survival and 5-year reoperation rates were 3.2%, 94.5% and 9.9%, respectively. The heterogeneities of the weighted mean differences (WMD) values of the AIG and AVG between preoperation and postoperation were extremely high (I² = 81.5%, p < 0.001 in AIG, I² = 97.6%, p = 0.003 in AVG). Subgroup analysis suggested that the AIG and AVG were improved by 3.03 grades (I² = 0%, p < 0.001) and 3.16 mmHg (I² = 0%, p < 0.001) in the European group, respectively. In the Asian group, the AIG and AVG were improved by 2.57 grades (I² = 0%, p < 0.001) and 34.39 mmHg (I² = 0%, p < 0.001), respectively. Compared with the values at discharge, the AIG was increased by 0.15 grades (I² = 0%, p = 0.031) and the AVG was still decreased by 2.07 mmHg (I² = 0%, p = 0.031) at the time of follow up. Valvuloplasty is safe and effective to treat rheumatic aortic insufficiency and stenosis, and the duration of maintenance required to improve stenosis was longer than that of insufficiency.

Ross procedure or complex aortic valve repair using pericardium in children: A real dilemma

OBJECTIVE

Difficult to repair aortic valve lesions, requiring the use of a valve substitute, remain controversial in the face of the Ross procedure, despite undeniable technical advances. This study was undertaken to compare midterm outcomes of children treated using the Ross procedure or aortic valvuloplasty for complex aortic valve lesions.

METHODS

Between January 2006 and December 2017, 126 patients aged younger than 18 years were treated for complex aortic stenosis and/or aortic insufficiency and were included in this retrospective study. Only aortic valve lesions requiring repair with an autologous or heterologous pericardial patch were considered complex lesions. Propensity score framework analyses were used to compare outcomes of the Ross and aortic valvuloplasty groups while controlling for confounders.

RESULTS

Among the 126 patients with complex aortic valve lesions, propensity score matching selected 34 unique pairs of patients with similar characteristics. Survival (aortic valvuloplasty, 94.1%; Ross, 91%; P = .89), freedom from overall reintervention (aortic valvuloplasty, 50.1%; Ross, 69%; P = .32), and freedom from infective endocarditis at 8 years (aortic valvuloplasty, 100%; Ross, 85.9%; P = .21) were similar. However, freedom from reintervention in the left ventricular outflow tract at 8 years was lower after aortic valvuloplasty than after the Ross procedure (50.1% vs 100%, respectively; P = .001).

CONCLUSIONS

Aortic valvuloplasty and the Ross procedure yielded similar 8-year outcomes regarding death, reoperation, and infective endocarditis although aortic valvuloplasty tended to be associated with fewer cases of infective endocarditis. Aortic valvuloplasty using a pericardial patch can be chosen as a first-line strategy for treating complex aortic valve lesions and might offer the possibility of a later Ross procedure.

Congenital aortic and truncal valve reconstruction using the Ozaki technique: Short-term clinical results

OBJECTIVES

Aortic valve reconstruction (AVRec) with neocuspidization or the Ozaki procedure with complete cusp replacement for aortic valve disease has excellent mid-term results in adults. Limited results of AVRec in pediatric patients have been reported. We report our early outcomes of the Ozaki procedure for congenital aortic and truncal valve disease.

METHODS

A retrospective analysis was performed on all 57 patients with congenital aortic and truncal valve disease who had a 3-leaflet Ozaki procedure at a single institution from August 2015 to February 2019. Outcome measures included mortality, surgical or catheter-based reinterventions, and echocardiographic measurements.

RESULTS

Twenty-four patients had aortic regurgitation (AR), 6 had aortic stenosis (AS), and 27 patients had AS/AR. Two patients had quadricuspid valves, 26 had tricuspid, 20 had bicuspid, and 9 had unicusp aortic valves. Four patients had truncus arteriosus. Thirty-four patients had previous aortic valve repairs and 5 had replacements. Preoperative echocardiography mean annular diameter was 20.90 ± 4.98 cm and peak gradient for patients with AS/AR was 53.62 ± 22.20 mm Hg. Autologous, Photofix, and CardioCel bovine pericardia were used in 20, 35, and 2 patients. Eight patients required aortic root enlargement and 20 had sinus enlargement. Fifty-one patients had concomitant procedures. Median intensive care unit and hospital length of stay were 1.87 and 6.38 days. There were no hospital mortalities or early conversions to valve replacement. At discharge, 98% of patients had mild or less regurgitation and peak aortic gradient was 16.9 ± 9.5 mm Hg. Two patients underwent aortic valve replacement. At median follow-up of 8.1 months, 96% and 91% of patients had less than moderate regurgitation and stenosis, respectively.

CONCLUSIONS

The AVRec procedure has acceptable short-term results and should be considered for valve reconstruction in pediatric patients with congenital aortic and truncal valve disease. Longer-term follow-up is necessary to determine the optimal patch material and late valve function and continued annular growth.

Performance of the ADAPT-Treated CardioCel® Scaffold in Pediatric Patients With Congenital Cardiac Anomalies: Medium to Long-Term Outcomes

Background: A Phase II Clinical Trial reviewed the performance (morbidity and calcification) of the tissue-engineered ADAPT® bovine pericardial scaffold (CardioCel®) in pediatric patients (n = 30) with congenital cardiac defects. In that study, CardioCel® demonstrated no graft-related morbidity and mortality in 25 patients, over 12 months. Five patients died due to non-graft-related events. Echocardiography revealed hemodynamically stable repairs with no calcification of the scaffold. Magnetic resonance imaging (MRI) at 12 months in 10 patients confirmed the absence of calcification. These patients were followed up for further up to 10 years. We present the results of this retrospective review of these patients that were followed for further medium to long-term (median 7.2 years, 25%: 3.6 years 75%: 9.25 years) postoperatively in these patients. Methods: Between April 2008 and September 2009, CardioCel® was implanted in 30 patients with congenital cardiac defects. Efficacy measures included graft-related mortality, morbidity and haemodynamic abnormalities. Calcification was assessed by standard 2D-M mode echocardiography and MRI at 12 months. Medium to long-term assessment included routine clinical assessments and echocardiography. Results: Median age at surgery was 18 months (27 days-13 years). Twenty-five patients (142 patient years) were followed for up to 10 years. The 10-year survival rate is estimated as 86.9% (95% CI 71.4-100.0%) over the entire follow-up period. One patient was lost to follow-up. No graft-related mortality was encountered up to a median follow-up of 7.2 years. Two patients died (pacemaker complications >5 years and arrhythmia >7 years postoperatively). No graft failure, thromboembolic events, infections or device-related reinterventions were recorded. Non-significant residual leaks occurred in 3 patients. Echocardiography demonstrated the absence of calcification in all implants. Conclusion: The tissue-engineered ADAPT® bovine pericardial scaffold demonstrated excellent medium to long-term performance (up to 10 years) when used as a scaffold for repair of congenital cardiac defects in children. Durability, acellularity, biostability and non-calcifying potential of CardioCel® makes it a very attractive tissue for congenital cardiac repair procedures.

Aortic valve neo-cuspidation using the Ozaki technique for acquired and congenital disease: where does this procedure currently stand?

The surgical treatment options for pediatric aortic valve disease are limited. The Ozaki procedure, which involves templated creation of new aortic valve leaflets, has proved to be a promising surgical technique. This review aims at elaborating the indications, technical intricacies, and outcomes of the aortic valve neo-cuspidization procedure (Ozaki procedure) in the pediatric population.

The great debate series: surgical treatment of aortic valve abnormalities in children

This article is the latest in an EJCTS series entitled 'The Great Debates'. We have chosen the topic of aortic valve (AoV) surgery in children, with a focus on infants and neonates. The topic was selected due to the significant challenges that AoV problems in the young may present to the surgical team. There are many areas of active controversy, despite the vast accumulated world experience. We have tried to incorporate many of these issues in the questions posed, not claiming to be all-inclusive. The individuals invited to this debate are experts in paediatric valve surgery, with broad and successful clinical experiences on multiple continents. We hope that the facts and opinions presented in this debate will generate interest and discussion and perhaps prove useful in decision-making for future complex valve cases.

Templates of flat pericardial patterns for precise aortic cusp extension

Background Aortic cusp extension is a subjective and operator-dependent technique. In order to facilitate surgical correction of aortic cusp retraction and reestablishment of adequate cusp coaptation, we sought to develop new templates that can be used to cut flat pericardial sheets into precise cusp extension patches. Methods Each template was designed as a two-dimensional unwrap of the natural geometry of a complete aortic cusp, and a series of templates were made available to correspond with all potential aortic cusp sizes. Based on these templates, aortic cusp extension was performed in 2 patients (aged 54 and 43 years) with significant retraction of the noncoronary aortic cusps and severe aortic valve insufficiency. In each patient, extension of the retracted native noncoronary cusp was undertaken using a bovine pericardial patch that matched the size of adjacent nondiseased native aortic cusps. Results Achieving geometrically perfect aortic cusp extensions was uncomplicated, and intraoperative transesophageal echocardiography confirmed satisfactory aortic valve repairs (aortic insufficiency < 1+ and low transvalvular gradients). Early follow-up transthoracic echocardiography confirmed that all valve cusps met at similar heights in the aortic root, and that their excursions were virtually identical. Conclusions The newly designed templates can be used to cut flat pericardial sheets into exact cusp extension patches, and initial clinical experience indicates that they are useful in performing precise aortic cusp extension procedures and restoring adequate aortic valve competence.

Photo-oxidized bovine pericardium in congenital cardiac surgery: single-centre experience

Objectives

Dye-mediated photo-oxidation of pericardium is an alternative method to chemical treatment with glutaraldehyde for cross-linking collagen, providing biostability of the patch material while avoiding late calcification and cytotoxicity. There are few data available, on using photo-oxidation-treated pericardium, in congenital cardiac surgery. This study reports the outcomes using Photofix™ bovine pericardium in neonates, infants, children and young adults undergoing paediatric cardiac surgery.

Methods

A total of 490 patches in 383 consecutive operations (364 patients) were used in the surgical repair of congenital heart defects at our institution from October 2008 to October 2011. Recorded variables included demographic data, age at operation, primary cardiac diagnosis, associated complications and number, type and location of patches placed and patch-related reintervention.

Results

Median age at operation was 5.3 years, ranging from <1 month to 56 years. The overall survival rate at late follow-up was 92%, and no deaths were related to failure of the tissue substitute. Two patients (0.5%) underwent reintervention late due to patch material failure: one for residual shunt after Rastelli repair and one for aneurysmal dilatation of a right ventricular outflow tract patch. The patch material was explanted in 8 patients at a mean of 20 months (range, 1-72 months) following implantation. Histological examination revealed mild to moderate inflammation with variable calcification.

Conclusions

Photo-oxidized bovine pericardium demonstrated excellent performance when used as a patch material in cardiovascular repair in children. Its handling characteristics and biocompatibility are consistent with a wide range of applications.

Histology of Pericardial Tissue Substitutes Used in Congenital Heart Surgery

Pericardium is used as a tissue substitute during pediatric heart surgery. However, little is known about the histological characteristics of pericardial tissue substitutes. We searched our clinical and Pathology databases to identify cases in which glutaraldehyde-preserved autologous pericardium, PhotoFix bovine pericardium, or Peri-Guard Repair Patch glutaraldehyde-preserved bovine pericardium was used as patch material during cardiac surgery and in which explanted tissue substitute was available for histologic examination. Tissue sections were stained with hematoxylin and eosin, Masson trichrome, and Movat pentachrome, and were graded for inflammation, tissue substitute degeneration, neointima formation, and calcification. Nonparametric statistical methods were used to test differences between groups because of small sample size. The eight patients who received PhotoFix pericardium were older (median 10 months vs 10 days, P < 0.05) and the material was in situ longer (median 14 vs 2.5 months, P < 0.05) compared to the eight who received autologous pericardium. Only three patients received glutaraldehyde-preserved bovine pericardium precluding statistical comparison. Inflammation and tissue degeneration were greater in PhotoFix pericardium compared to autologous pericardium but were no more than moderate. Neointima formation and calcification did not differ significantly between the two groups. PhotoFix bovine pericardium is associated with more inflammation and material degeneration but calcification, and neointima formation are similar to autologous pericardium. Although the short-term outcomes are acceptable, calcification and degeneration seen in some cases suggest that long-term outcomes and performance at certain anatomic locations need further study.

Normal echocardiographic mitral and aortic valve thickness in children

OBJECTIVE

We aimed to define the normal range of aortic and mitral valve thickness in healthy schoolchildren from a high prevalence rheumatic heart disease (RHD) region, using a standardised protocol for imaging and measurement.

METHODS

Measurements were performed in 288 children without RHD. Anterior mitral valve leaflet (AMVL) thickness measurements were performed at the midpoint and tip of the leaflet in the parasternal long axis (PSLA) in diastole, when the AMVL was approximately parallel to the ventricular septum. Thickness of the aortic valve was measured from PSLA imaging in systole when the leaflets were at maximum excursion. The right coronary and non-coronary closure lines of the aortic valve were measured in diastole in parasternal short axis (PSSA) imaging. Results were compared with 51 children with RHD classified by World Heart Federation diagnostic criteria.

RESULTS

In normal children, median AMVL tip thickness was 2.0 mm (IQR 1.7-2.4) and median AMVL midpoint thickness 2.0 mm (IQR 1.7-2.4). The median aortic valve thickness was 1.5 mm (IQR 1.3-1.6) in the PSLA view and 1.4 mm (IQR 1.2-1.6) in the PSSA view. The interclass correlation coefficient for the AMVL tip was 0.85 (0.71 to 0.92) and for the AMVL midpoint was 0.77 (0.54 to 0.87).

CONCLUSIONS

We have described a standardised method for mitral and aortic valve measurement in children which is objective and reproducible. Normal ranges of left heart valve thickness in a high prevalence RHD population are established. These results provide a reference range for school-age children in high prevalence RHD regions undergoing echocardiographic screening.

Cardiac surgery in Africa: a thirty-five year experience on open heart surgery in Cote d'Ivoire

BACKGROUND

Few centers for open heart surgery (OHS) are in Sub-Saharan Africa. Lack of OHS results is also noted. By reporting our African experience on OHS, the aim of this study was to fill the gap.

METHODS

It is a retrospective study on 2,612 patients who were subject to an OHS between 1978 and 2013. Data were collected from demographical, clinical, investigative studies, surgical and outcomes parameters.

RESULTS

There were 1,475 cases of rheumatic heart diseases (RHD), 126 endomyocardial fibrosis (EMF), 741 congenital heart diseases (CHDs) and 270 various affections. Related to rheumatic valvular surgery we enumerated 1,175 monovalvular (mitral n=778, aortic n=336, tricuspid n=61); 280 bivalvular (mitral + aortic n=150, mitral + tricuspid n=130) and 20 trivalvular. For RHD, average age was 26±10.1 years (4-69 years) and 60% of our patients presented a functional class III or IV according to New York Heart Association (NYHA) classification. A total of 1,481 valvular replacements (bioprostheses n=489, mechanical prostheses n=992) and 445 valvular repair were carried out with a global and late mortality surgery respectively at 7% and 8%. One hundred and twenty-six [126] cases of EMF with right sided form 39, left sided form 40, and bilateral form 47 were colligated. Average age was 12±0.6 years (2-15 years). All patients with EMF underwent surgery; an endocardectomy in all patients combined with valvular reconstruction (n=36) or valvular replacement (n=90) was carried out with a hospital mortality at 16% (n=20). Concerning CHD, the most frequent were ventricular septal defect (VSD) (n=240), atrial septal defect (ASD) (n=200), partial atrio-ventricular sepal defect (n=30) and tetralogy of Fallot (T4F) (n=220), a total correction was performed for those CHD with an early mortality at 6.4% (n=44).

CONCLUSIONS

OHS in Cote d'Ivoire was successfully performed in most of our patients, the spectrum of acquired valvular heart diseases and CHDs in our country is similar to others in Sub-Saharan Africa.

CorMatrix valved conduit in a porcine model: long-term remodelling and biomechanical characterization

OBJECTIVES

Porcine small intestinal submucosa extracellular matrix (CorMatrix; CorMatrix Cardiovascular, Rosewell, GA) is a relatively novel tissue substitute used in cardiovascular applications. We investigated the biological reaction and remodelling of CorMatrix as a tri-leaflet valved conduit in a pig model. We hypothesized that CorMatrix maintains a durable architecture as a valved conduit and remodels to resemble surrounding tissues.

METHODS

We fashioned the valved conduit using a 7 × 10 cm 4-ply CorMatrix sheet and placed it in the thoracic aorta of seven landrace pigs for 3, 4, 5 and 6 months. Biodegradation, replacement by native tissue, strength and durability were examined by histology, immunohistochemistry and mechanical testing.

RESULTS

Four pigs, one per time frame, completed the study. The conduit lost its original architecture as a tri-leaflet valve due to cusp immobility, subsequent attachment to the wall segment and consequent maintenance of a thick arterial wall-like structure. Scaffold resorption was incomplete, with disorganized inconsistent spatial and temporal degradation even at 6 months. Fibrosis, scarring and calcification started at 4 months and chronic inflammation persisted. The partially remodelled scaffold did not resemble the aortic wall, suggesting impaired remodelling. Mechanical testing showed progressive weakening of the tissues over time, which were liable to breakage.

CONCLUSIONS

CorMatrix is biodegradable; however, it failed to remodel in a structured and anatomical fashion in an arterial environment. Progressive mechanical and remodelling failure in this scenario might be explained by the complexity of the conduit design and the host's chronic inflammatory response, leading to early fibrosis and calcification.

Cusp repair during aortic valve-sparing operation: technical aspects and impact on results

AIMS

Aortic valve-sparing operations are nowadays considered safe and reliable procedures in terms of mid-term and long-term results. Although surgical techniques regarding the modality of grafts' implantation have been properly addressed, the modality of cusp repair, when needed, is still open to debate. We sought to review the literature to try to shed light on when the cusp repair is required and how it should be performed.

METHODS

We searched the PubMed database using the keywords aortic valve-sparing operation, aortic valve-sparing reimplantation, valve-sparing aortic root replacement, aortic valve repair, and aortic cusp repair. Only studies that included and described in detail the technique of cusp repairs in adjunct to aortic valve-sparing operation were considered.

RESULTS

Bicuspid aortic valve more often requires correction when compared with tricuspid valve. The range of the techniques varies from the 'simple' free margin plication to the more complex triangular resection with patch repair. Results in the literature seem to be encouraging, showing that, in most of the cases, cusp repair does not affect valve competence in the mid-term and long-term.

CONCLUSION

Correction of the cusp is a delicate balance between undercorrection that could lead to residual prolapse and overcorrection that could lead to cusp restriction. Although complex repair of the aortic valve in addition to root replacement provided satisfactory results, it should be reserved for experienced centers with a large volume of patients.

Neonatal Mitral Valve Repair in Biventricular Repair, Single Ventricle Palliation, and Secondary Left Ventricular Recruitment: Indications, Techniques, and Mid-Term Outcomes

Objectives

Although mitral valve repair is rarely required in neonates, this population is considered to be at high risk for adverse outcomes. The aim of this study was to review the indications for surgery, mechanisms, repair techniques, and mid-term outcomes of neonatal mitral valve repair.

Methods

The demographic, procedural, and outcome data were obtained for all neonates who underwent mitral valve repair from 2005 to 2012. The primary endpoints included mortality, transplantation, and mitral valve reoperation.

Results

Twenty patients were included during the study period. Median age at operation was 11 days (range: 3–25). Eleven patients (55%) presented with mitral stenosis, three had regurgitation (15%), and six had mixed mitral disease (30%). Nineteen of 20 patients had mild or less regurgitation on immediate postoperative imaging. During a median follow-up of 5 months (1 month–4.8 years), six patients died at a median of 33 months (7–41 months) from repair and one patient required orthotopic heart transplantation. Six patients required mitral valve reoperation, five for mitral valve re-repair, and one for mitral valve replacement. Freedom from death, transplantation, or mitral valve replacement was 84.2 ± 8.4% at 1 month, 71.3 ± 11% at 6 months, 64.1 ± 12% at 1 year, and 51.3 ± 15% at 2 years and was worse for patients presenting with mitral regurgitation compared to stenosis or mixed mitral valve disease.

Conclusion

Although mitral valve repair can be performed with acceptable immediate postoperative result, this procedure carries a high burden of late death and mitral valve reoperations.

Partial aortic valve replacement: a new and simple approach for endocarditis

We describe the replacement of a single cusp in two patients with severe aortic regurgitation due to endocarditis with a one third stentless bioprosthesis, with excellent results in both.

Repair options in rheumatic aortic valve disease in young patients: potential problems with pericardial cusp extension

This article outlines the arguments against cusp extension, which were put forward at the debate entitled "Repair options in rheumatic aortic disease in young patients" at the Symposium on Surgery for Rheumatic Heart Disease organized by The World Society for Pediatric and Congenital Heart Surgery at The Sixth World Congress of Paediatric Cardiology and Cardiac Surgery, February 17-22, 2013, Cape Town, South Africa. We propose that cusp extension should be avoided because (1) these patients are usually old enough to receive the same valve substitutes as adults, (2) lack of antibioprophylaxis compliance will likely result in early reintervention, (3) cusp extension mandates rerepair within four to five years and is more expensive in the long term, and (4) it is fraught with myocardial ischemic complications. Thus, a mechanical, bioprosthetic, or autograft valve replacement may be superior for patients unless they have unrestricted access to repetitive interventions. A single surgical technique does not suffice in the treatment of rheumatic aortic valve disease, and a diversified approach should be adopted dependent on both the patients' characteristics and the financial constraints.

New engineering treatment of bovine pericardium confers outstanding resistance to calcification in mitral and pulmonary implantations in a juvenile sheep model

OBJECTIVE

To conduct a test of noninferiority for CardioCel (Admedus, Brisbane, Australia), a chemically engineered bovine pericardium over autologous pericardium treated intraoperatively with glutaraldehyde in a chronic juvenile sheep model of pulmonary valve (PV) and mitral valve (MV) reconstruction.

METHODS

We replaced the posterior leaflet of the MV and of 1 PV cusp with patches in ewes aged 10 months. There were 2 groups: CardioCel (n = 6) and control (n = 4). All valves were competent. Echocardiography was performed before euthanasia. The collected data were function, macroscopy, histology, and calcium contents. The primary end points were thickening and calcium content.

RESULTS

All animals survived until sacrifice after 7 months. The valves had normal echo. The macroscopic aspect of the valves was excellent. Examination of the slides for both groups revealed a continuous endothelium on both sides of the patch and a layer of new collagen developed on both sides between patch and endothelium and interstitial cells and smooth muscle cell in these layers. The patch had not thickened but the 2 layers of new collagen for the PV showed a median thickening of 37% in the CardioCel group and 111% in the control group (P = .01), and for the MV a thickening of 108% and 251%, respectively, was seen (P = .01). The median calcium content in the PV was 0.24 μg/mg (range, 0.19-0.30) in the CardioCel group versus 0.34 μg/mg (range, 0.24-0.62) in controls (P = .20). In the MV it was 0.46 μg/mg (range, 0.30-1.0) in the CardioCel group and 0.47 μg/mg (range, 0.29-1.9) in controls (P = 1.0).

CONCLUSIONS

In this growing lamb model the CardioCel patch allowed accurate valve repair at both systemic and pulmonary pressure. The mechanical properties of CardioCel after 7 months were preserved with a more controlled healing than the treated autologous pericardium and without calcification.

Biodegradable materials for surgical management of infective endocarditis: new solution or a dead end street?

Background

One third of patients with infective endocarditis will require operative intervention. Given the superiority of valve repair over valve replacement in many indications other than endocarditis, there has been increasing interest and an increasing number of reports of excellent results of valve repair in acute infective endocarditis. The theoretically ideal material for valve repair in this setting is non-permanent, “vanishing” material, not at risk of seeding or colonization. The goal of this contribution is to review currently available data on biodegradable materials for valve repair in infective endocarditis.

Discussion

Rigorous electronic and manual literature searches were conducted to identify reports of biodegradable materials for valve repair in infective endocarditis. Articles were identified in electronic database searches of Medline, Embase and the Cochrane Library, using a predetermined search strategy. 49 manuscripts were included in the review. Prosthetic materials needed for valve repair can be summarized into annuloplasty rings to remodel the mitral or tricuspid annulus, and patch materials to replace resected valvar tissue. The commercially available biodegradable annuloplasty ring has shown interesting clinical results in a single-center experience; however further data is required for validation and longer follow-up. Unmodified extra-cellular matrix patches, such as small intestinal submucosa, have had promising initial experimental and clinical results in non-infected valve repair, although in valve repair for endocarditis has been reported in only one patient, and concerns have been raised regarding their mechanical stability in an infected field.

Summary

These evolving biodegradable devices offer the potential for valve repair with degradable materials replaced with autologous tissue, which could further improve the results of valve repair for infective endocarditis. This is an evolving field with promising experimental or initial clinical results, however long-term outcomes are lacking and further data is necessary to validate this theoretically interesting approach to infective endocarditis.

In vitro study of a standardized approach to aortic cusp extension

PURPOSE

Cusp extension technique (CET) is a reparative surgical procedure for restoring aortic valve function by suturing patches to the compromised native leaflets. Its outcomes are strongly dependent on the ability of the surgeon. We proposed and tested a novel approach on an in vitro model, aimed at standardizing and simplifying the surgical procedure.

METHODS

A set of standard pre-cut bovine pericardium patches, available in different sizes, was developed. The surgeon can choose the leaflet-specific patches to be implanted according to the patient anatomy, using a geometrical model of the aortic valve whose inputs are the measured intercommissural distances. The hemodynamic performance of this approach was evaluated on porcine aortic roots in a pulsatile mock loop. Hydrodynamic and kinematic evaluation of the samples was provided.

RESULTS

After CET, mean and maximum pressure drops were 3.1±1.3 mmHg and 25.4±5.0 mmHg respectively, and EOA was 3.8±0.8 cm.

CONCLUSIONS

Our approach to cusp extension proved to be reliable and effective in restoring valve functioning, without significantly altering the physiological kinematics. The use of pre-cut patches considerably simplified the surgery, increasing standardization and repeatability.

Outcome of a Repair-Oriented Strategy for the Aortic Valve in Children

Background:

We sought to evaluate the mid-term results of a repair-oriented strategy of the aortic valve in children.

Methods:

Between February 2007 and November 2011, we performed 39 aortic valve repairs in children. Median age and weight at surgery were 5.5 years (3 days-18 years) and 16.7 kg (2.7-83.5), respectively. A total of 11 (28%) patients had one or more prior surgical or interventional cardiologic procedures. Median intensive care unit and hospital stay were two (1-96) and five (3-96) days, respectively. Median and cumulative follow-up were 12.7 months (15 days-64 months) and 48.9 patient-years, respectively.

Results:

There were 3 (7.7%) early deaths all in patients undergoing additional complex cardiac procedures. Two (5.1%) patients required early surgical revision. Twenty-six (66%) patients had isolated or mixed aortic stenosis. The median gradient reduced from 62.4 (range 16-144) to 17.6 mm Hg (range 0-51.8), postoperatively ( P = .02). At last follow-up, the median gradient remained largely unchanged at 21.1 mm Hg (0-49; P = .02). Twenty-six (66%) patients had isolated or mixed aortic valve regurgitation (mild in 8 [20%], moderate in 15 [38%], and severe in 6 ([15%] patients). The degree of aortic regurgitation improved in all patients with moderate or severe aortic regurgitation ( P = .04). At last follow-up, two patients had moderate aortic regurgitation. Kaplan Meier freedom from reintervention in the survivors was 95% at three years.

Conclusions:

A repair-oriented strategy for the aortic valve in children has satisfactory early and mid-term results and remains a promising management option in children with aortic valve disease.

Valve-sparing aortic root replacement and remodeling with complex aortic valve reconstruction in children and young adults with moderate or severe aortic regurgitation

OBJECTIVES

The durability of valve-sparing aortic root procedures with aortic regurgitation due to leaflet disease is questioned. Here, we review our experience in combined aortic root and valve reconstruction in children and young adults.

METHODS

All valve-sparing aortic root procedures from 2000 to 2012 were reviewed, and patients with aortic valve repair beyond resuspension were included. Root procedures were classified as replacement with reimplantation, root remodeling, or aortic annular and sinotubular junction stabilization. The primary end point was structural valve deterioration, a composite of aortic valve reoperation and/or moderate or greater regurgitation at follow-up.

RESULTS

Thirty-four patients were included during the study period. The surgery consisted of reimplantation in 13 patients, remodeling in 16 patients, and annular and sinotubular junction stabilization in 5 patients. Valve repair consisted of leaflet procedures in 26 patients and subannular reduction in 15 patients. During a median follow-up of 4.2 months (range, 2 weeks-8 years), there were 5 reoperations for aortic valve replacement due to aortic regurgitation, and 2 patients presented with moderate or greater regurgitation. Freedom from structural valve deterioration was 70.1% ± 10.3% at 1 year and remained stable thereafter, although it was significantly worse in the reimplantation group (P = .039). A more severe degree of preoperative aortic regurgitation (P = .001) and smaller graft to aortic annulus ratio (P = .003) were predictors of structural valve deterioration.

CONCLUSIONS

Valve-sparing root and valve reconstruction can be done with low operative risk and allows valve preservation in most patients. These data should question the assumption that reimplantation is superior when associated with complex valve reconstruction.

Aortic valve repair and replacement in children

ABSTRACT: Several aortic valve (AV) pathologies might necessitate intervention. Percutaneous or surgical AV repair is generally recommended as the initial management strategy in children with AV disease, offering the advantage of stabilization of the heart dimensions and improvement of patients‘ symptoms. When AV repair is not possible or fails, AV replacement is necessary and is associated with several challenges in children. This review will focus on treatment strategy, AV repair techniques, AV replacement choices and outcomes of AV disease management in children.

Aortic valve replacement in children: Options and outcomes

Several disease pathologies such as congenital heart disease and rheumatic fever can affect the aortic valve (AV) in children frequently necessitating intervention. While percutaneous or surgical AV repair is recommended as initial management strategy in children with AV disease, AV replacement (AVR) might become necessary in children with significant valve destruction and after repair or intervention failure. AVR in children is associated with distinct clinical and technical problems owing to several anatomic, social and prosthesis-related issues. In the current review, we list different AV substitutes, discuss their advantages and shortcomings, outline AVR results in children, and explore the divergence of outcomes in various age, anatomy and pathology subgroups; all in the aim to identify optimal AVR choice for each patient taking into consideration his unique anatomic and demographic characteristics.

Aortic Cusp Extension for Surgical Correction of Rheumatic Aortic Valve Insufficiency in Children

Surgical management of aortic insufficiency in the young is problematic because of the lack of an ideal valve substitute. Potential advantages of aortic valve repair include low incidences of thromboembolism and endocarditis, avoiding conduit replacements, the maintenance of growth potential, and improved quality of life. Aortic valve repair is still far from fulfilling the three key factors that have allowed the phenomenal development of mitral valve repair (standardization, reproducibility, and stable long-term results); however, techniques of aortic valve repair have been refined, and subsets of patients amenable to repair have been identified. We have focused on the oldest technique of aortic valve repair, cusp extension, focusing on children with rheumatic aortic insufficiency. Among 77 children operated from 2003 to 2007, there was one early death from ventricular failure and one late death from sudden cardiac arrhythmia. During a mean follow-up of 12.8 ± 5.9 years, there were 16 (20.5%) reoperations on the aortic valve, at a median of 3.4 years (range, 2 months to 18.3 years) from repair. Freedom from aortic valve reoperation was 96.2% ± 2.2% at 1 year, 94.9% ± 2.5% at 2 years, 88.5% ± 3.6% at 5 years, 81.7% ± 4.4% at 10 years, 79.7% ± 4.8% at 15 years, and 76.2% ± 5.7% at 20 years. Although aortic cusp extension is technically more demanding, it remains particularly more suitable in the context of evolving rheumatic aortic insufficiency in children with a small aortic annulus as a bridge surgical approach to late aortic valve replacement with a larger valvular prosthesis.

Attitude after a mild aortic valve lesion during rheumatic mitral valve surgery

OBJECTIVE

We evaluated whether rheumatic aortic valve disease of mild degree should be treated in patients undergoing mitral valve surgery.

METHODS

From 1992 to 2010, 197 patients (aged 52 [19-82] years, male:female = 60:137) who had rheumatic mitral valve disease and mild aortic valve disease were enrolled. The aortic valve was untreated in 114 patients (no treatment group), repaired in 40 patients (aortic valvuloplasty group), and replaced in 43 patients (aortic valve replacement group).

RESULTS

Operative mortality occurred in 4 patients (2.0%). There were no differences in early mortality and postoperative complications among the 3 groups. Overall survival at 5, 10, and 15 years was 96.3%, 92.1%, and 85.7%, respectively. In the no treatment group, progression-free survival in significant aortic valve disease at 5, 10, and 15 years was 98.7%, 91.3%, and 81.1%, respectively. This was not superior in the aortic valvuloplasty group (85.9%, 77.6%, and 69.8%, respectively) than in the no treatment group. Freedom from aortic valve disease was lower in patients with aortic stenosis than in those with aortic regurgitation in univariate and multivariable analyses (P < .001). Reoperation was performed in 19 patients, including 2 aortic valve reoperations. Aortic valve-related event-free survival was similar among the 3 groups.

CONCLUSIONS

Mild aortic valve disease in patients undergoing rheumatic mitral valve surgery could be left untreated, because preventive aortic valve operation does not result in better clinical and echocardiographic outcomes.

World Heart Federation criteria for echocardiographic diagnosis of rheumatic heart disease--an evidence-based guideline

Over the past 5 years, the advent of echocardiographic screening for rheumatic heart disease (RHD) has revealed a higher RHD burden than previously thought. In light of this global experience, the development of new international echocardiographic guidelines that address the full spectrum of the rheumatic disease process is opportune. Systematic differences in the reporting of and diagnostic approach to RHD exist, reflecting differences in local experience and disease patterns. The World Heart Federation echocardiographic criteria for RHD have, therefore, been developed and are formulated on the basis of the best available evidence. Three categories are defined on the basis of assessment by 2D, continuous-wave, and color-Doppler echocardiography: 'definite RHD', 'borderline RHD', and 'normal'. Four subcategories of 'definite RHD' and three subcategories of 'borderline RHD' exist, to reflect the various disease patterns. The morphological features of RHD and the criteria for pathological mitral and aortic regurgitation are also defined. The criteria are modified for those aged over 20 years on the basis of the available evidence. The standardized criteria aim to permit rapid and consistent identification of individuals with RHD without a clear history of acute rheumatic fever and hence allow enrollment into secondary prophylaxis programs. However, important unanswered questions remain about the importance of subclinical disease (borderline or definite RHD on echocardiography without a clinical pathological murmur), and about the practicalities of implementing screening programs. These standardized criteria will help enable new studies to be designed to evaluate the role of echocardiographic screening in RHD control.

Aortic valve reconstruction in the young infants and children

Considering the structure and function of the aortic root, changes in the aortic valve leaflets and changes in the geometry of the aortic root are the two primary causes of aortic valve dysfunction. In adults, aortic valve sparing reconstruction has a long history beginning in the 1970s, where tensor fascia was used for leaflet repair in patients with isolated aortic regurgitation and ascending aortic replacement was used in patients with ascending aortic aneurysms or aortic ectasia. Subsequent progress in the 1980s and 1990s led to pericardial leaflet replacement and aortic root re-implantation and remodeling. However, it has not been until the last decade that these concepts and techniques have been applied in younger patients focusing on the conotruncus, valvar apparatus, sino-tubular junction, and ascending aorta.

Advances in aortic valve repair: focus on functional approach, clinical outcomes, and central role of echocardiography

The surgical classification of aortic regurgitation (AR) is based on cusp mobility. Based on this classification, there are 3 classes of AR: type I is defined as normal cusp mobility, type II is defined as excessive cusp mobility, and type III is defined as restricted cusp mobility. Patients often have multiple coexisting mechanisms. Because aortic valve (AV) repair is safe, effective, and durable, it likely will become a mainstream surgical option for the management of significant AR, even in the setting of a bicuspid valve. Intraoperative transesophageal echocardiography has a central role at all stages in AV repair. Before cardiopulmonary bypass, it can accurately diagnose the mechanism of AR to guide operative strategy for successful repair. After separation from cardiopulmonary bypass, it can comprehensively evaluate the AV repair, including the likelihood that the repair will be durable in the long-term. Important echocardiographic predictors of a durable AV repair include the absence of AR, cusp coaptation above the annular plane, a coaptation length >4 mm, and an effective cusp height >8 mm. The clinical applicability of AV repair continues to expand and likely will evolve into a mainstream surgical therapy for AR, including minimally invasive techniques.