Analysis of Fluid-Structure Interaction Mechanisms for a Native Aortic Valve, Patient-Specific Ozaki Procedure, and a Bioprosthetic Valve

The Ozaki procedure is a surgical technique which avoids to implant foreign aortic valve prostheses in human heart, using the patient's own pericardium. Although this approach has well-identified benefits, it is still a topic of debate in the cardiac surgical community, which prevents its larger use to treat valve pathologies. This is linked to the actual lack of knowledge regarding the dynamics of tissue deformations and surrounding blood flow for this autograft pericardial valve. So far, there is no numerical study examining the coupling between the blood flow characteristics and the Ozaki leaflets dynamics. To fill this gap, we propose here a comprehensive comparison of various performance criteria between a healthy native valve, its pericardium-based counterpart, and a bioprosthetic solution, this is done using a three-dimensional fluid-structure interaction solver. Our findings reveal similar physiological dynamics between the valves but with the emergence of fluttering for the Ozaki leaflets and higher velocity and wall shear stress for the bioprosthetic heart valve.

Ectopic Calcification in Congenital Heart Surgery: A Material-Centric Review

The modern congenital heart surgeon has an array of materials available for cardiovascular repair. With advancements in the surgical outcomes for pediatric cardiac defects, choice of material has become increasingly dependent on late-term complications associated with each material. Calcification is a leading long-term complication and is increasing in prevalence with materials lasting longer in patients. Material calcification can impair functionality, lead to subsequent complications, and require additional interventions. A comprehensive literature review was conducted to investigate ectopic calcification of commonly used materials for congenital heart defect repair. Mechanisms of ectopic calcification among commonly used materials were investigated. Ectopic calcification is initiated by material-specific immunological reactions. Recent efforts have focused on developing new materials that are not prone to calcification. ePTFE was widely used in cardiovascular applications but still has reported instances of calcification in various situations, such as long-term use. Tissue engineering techniques have shown reduced calcification in reports. Calcification can occur in all conventional materials we reviewed and, in some cases, has led to life-threatening complications. Favorable outcomes have been reported with tissue-engineered materials, with the expectation of continued positive results in future reports. With an array of synthetic and biological materials now displaying acceptable surgical and short-term outcomes, there is a pressing need to review the long-term viability of these materials, especially considering improved patient survival to adulthood. Furthermore, developing new materials to mitigate calcification remains a promising avenue of research in this field.

Short-Term Results With Ozaki Valved Conduit-A Simple Solution for Patients Needing Right Ventricle to Pulmonary Artery Conduit in a Low-Resource Setting

BACKGROUND

The repair of certain types of complex congenital cardiac defects may require a right ventricle-pulmonary artery (RV-PA) conduit. Using the Ozaki Aortic valve neocuspidization (AVNeo)technique, a valved RV-PA conduit was constructed with an Ozaki valve inside a Dacron graft. This study aims to evaluate the short-term outcome of the Ozaki valved RV-PA conduit.

MATERIAL/METHOD

A total of 22 patients received the Ozaki valved RV-PA conduit from November 2019 until December 2023. The median age was 12 years (interquartile range [IQR], 5.5-21), median body weight was 35 kg (IQR, 15.8-48.5). The conduit was used in 16 patients (72.7%) under 18 years of age. Indications for conduit placement included: anatomic repair of corrected transposition of the great arteries, ventricular septal defect/pulmonary stenosis, conduit replacement, pulmonary atresia with associated anomalies, pulmonary artery aneurysm with dysplastic pulmonary valve, tetralogy of Fallot with coronary artery crossing the right ventricular outflow tract, bioprosthetic pulmonary valve regurgitation, and rheumatic heart disease. Native pericardium was used for the Ozaki valve in 12 patients and bovine pericardium for 10 patients. Conduit sizes ranged from 18 mm to 30 mm.

RESULT

The median intensive care unit stay was 4 (IQR, 2-6) days and the median hospital stay was 9 (IQR, 5.5-13.5) days. There were two perioperative mortalities (9.1%) both unrelated to the conduit. The median follow-up was 12.3 (IQR, 4.43-21.2) months. There was no infective endocarditis of the conduit. The median peak gradient across the conduit was 22 mm Hg (range 0-44 mm), and all were competent with trivial regurgitation on follow up.

CONCLUSION

Creation of an Ozaki valved conduit is an attractive option due to low cost, reproducibility, and excellent hemodynamics. Longer-term studies are needed to confirm the durability.

Geophysics-Inspired Nonlinear Stress-Strain Law for Biological Tissues and Its Applications in Compression Optical Coherence Elastography

We propose a nonlinear stress-strain law to describe nonlinear elastic properties of biological tissues using an analogy with the derivation of nonlinear constitutive laws for cracked rocks. The derivation of such a constitutive equation has been stimulated by the recently developed experimental technique-quasistatic Compression Optical Coherence Elastography (C-OCE). C-OCE enables obtaining nonlinear stress-strain dependences relating the applied uniaxial compressive stress and the axial component of the resultant strain in the tissue. To adequately describe nonlinear stress-strain dependences obtained with C-OCE for various tissues, the central idea is that, by analogy with geophysics, nonlinear elastic response of tissues is mostly determined by the histologically confirmed presence of interstitial gaps/pores resembling cracks in rocks. For the latter, the nonlinear elastic response is mostly determined by elastic properties of narrow cracks that are highly compliant and can easily be closed by applied compressing stress. The smaller the aspect ratio of such a gap/crack, the smaller the stress required to close it. Upon reaching sufficiently high compressive stress, almost all such gaps become closed, so that with further increase in the compressive stress, the elastic response of the tissue becomes nearly linear and is determined by the Young's modulus of the host tissue. The form of such a nonlinear dependence is determined by the distribution of the cracks/gaps over closing pressures; for describing this process, an analogy with geophysics is also used. After presenting the derivation of the proposed nonlinear law, we demonstrate that it enables surprisingly good fitting of experimental stress-strain curves obtained with C-OCE for a broad range of various tissues. Unlike empirical fitting, each of the fitting parameters in the proposed law has a clear physical meaning. The linear and nonlinear elastic parameters extracted using this law have already demonstrated high diagnostic value, e.g., for differentiating various types of cancerous and noncancerous tissues.

Calcification and atheroma plaques: is there any impact on the anatomical features of the aortic root and its elements?

OBJECTIVES

Morphometric information of the structures within the borders of the aortic root is a guide for surgical interventions. It is essential to determine the effects of aortic calcification and atheroma plaque findings on the structures of this region. This study aims to establish the normal values of aortic root structures and to investigate the impact of pathologic findings in order to guide diagnosis and treatment in the clinic.

METHODS

The aortic root structures were morphometrically analyzed in fresh hearts of 110 patients (89 males, 21 females) brought to the forensic medicine institution. The distances between the bases of the aortic sinuses, their widths and heights, and the lengths of the commissures were measured to differentiate between pathologic and non-pathologic aortic classes. Parameters were compared according to gender, age, body mass index, and body surface area.

RESULTS

The mean age was 44.71 ± 15.57 years in 21 female patients and 53.66 ± 15.67 years in 89 male patients. The results of the pathologic aorta group with calcification and atheroma plaque findings were higher than the non-pathologic aorta group in all parameters (P < .05).

CONCLUSIONS

Calcification and the presence of atheroma plaque in the aorta increase the size of the structures at the aortic root. Gender, age, body mass index, and body surface area are among the criteria that will cause changes in the structures of this region. These results will help surgeons to know the normal values of aortic root structures and to consider the effects of pathologic findings in aortic valve repair operations.

Precise reconstruction of the aortic valve using glutaraldehyde-treated autologous pericardium in new formula: a case report

BACKGROUND

The current study presents a novel and precise surgical technique for complete reconstruction of the aortic valve using glutaraldehyde-treated autologous pericardium in a patient with aortic valve disease and endocarditis. The technique aims to provide a more effective and reproducible method for aortic valve repair, with the goal of improving outcomes and quality of life for patients with aortic valve disease.

CASE PRESENTATION

A 35-year-old Iranian male with aortic valve disease and endocarditis underwent aortic valve reconstruction surgery. Preoperative echocardiography showed a degenerative aortic valve with severe regurgitation, reduced left ventricular ejection fraction, and specific aortic root dimensions. The surgical technique involved precise measurements and calculations to design the size and shape of the new aortic valve cusps using autologous pericardium, with the goal of optimizing coaptation and function. The surgeon calculated the intercommissural distance based on the aortic annulus diameter to determine cusp size and shape. He tailored the pericardial cusps to have a height equal to 80% of the coaptation margin length. Detailed suturing techniques were used to ensure proper alignment and coaptation of the new cusps. Intraoperative evaluation of the valve function using suction and transesophageal echocardiography showed good coaptation and minimal residual regurgitation. At the 3-year follow-up, the patient had a well-functioning aortic valve with only trivial leak and was in satisfactory clinical condition.

CONCLUSIONS

Glutaraldehyde-treated autologous pericardium is a validated leaflet alternative, and the causes of its failure are late annular dilatation and other technique breakdowns. Current evidence reveals that aortic valve reconstruction with glutaraldehyde-treated autologous pericardium is associated with many advantages with the potential to improve patient outcomes and quality of life. Further clinical studies are warranted to evaluate the long-term durability and efficacy of this approach.

Midterm results after aortic valve neocuspidization

Objectives

Aortic valve neocuspidization with autologous pericardium is gaining increasing attention as a surgical treatment option for aortic valve disease. However, little is known about midterm durability and valve-related events.

Methods

Patients undergoing aortic valve neocuspidization between 2016 and 2021 were included. Transthoracic echocardiography was performed before the operation, at discharge, and annually thereafter. Data were analyzed for incidences of structural valve deterioration, bioprosthetic valve failure, survival, freedom from reoperation, and hemodynamic performance.

Results

A total of 162 patients underwent aortic valve neocuspidization (mean age, 52.6 ± 16.6 years; range, 13-78 years); 114 (70.4%) were male. A total of 132 patients presented with a bicuspid aortic valve (81.5%) and 126 patients presented with aortic valve stenosis (77.8%). Concomitant procedures were performed in 63 patients (38.9%). Mean follow-up was 3.5 ± 1.2 years. At discharge, peak and mean pressure gradients were 15.6 ± 7.2 mm Hg and 8.4 ± 3.7 mm Hg, respectively, with a mean effective orifice area of 2.4 ± 0.8 cm2. After 5 years, peak and mean pressure gradients were 14.5 ± 4.6 mm Hg and 7.5 ± 2.2 mm Hg, respectively, with a mean effective orifice area of 2.3 ± 0.8 cm2. At 5 years, cumulative incidences of moderate and severe structural valve deterioration and bioprosthetic valve failure were 9.82% ± 3.87%, 6.96% ± 3.71%, and 12.1% ± 4.12%, respectively. Survival was 97.3% ± 1.4%, and freedom from reoperation was 91.3% ± 2.4%.

Conclusions

Aortic valve neocuspidization accomplishes low pressure gradients early after initial surgery and during follow-up. Survival in this young patient population is excellent. The main reason for reoperation is endocarditis, and rates for structural valve degeneration are low.

Midterm Outcomes After Aortic Valve Neocuspidization (Ozaki Procedure) in Adults

BACKGROUND

Trileaflet aortic valve neocuspidization (AVN) using autologous pericardium (Ozaki procedure) is an emerging surgical treatment option for aortic valve diseases. Although excellent results have been reported from Japan, data pertaining to its use in the United States are sparse.

METHODS

All adult patients who underwent AVN (AVN group) or surgical aortic valve replacement (SAVR) with a bioprosthetic valve (SAVR group) between 2015 and 2022 were identified. Propensity score matching was used to adjust the baseline characteristics between the 2 groups.

RESULTS

A total of 101 patients underwent AVN, and 1816 patients underwent SAVR with a bioprosthetic valve. None in the AVN group required conversion to SAVR. Before matching, mean age in the AVN group was 68.5 ± 8.8 years, and 56 patients (55.4%) underwent concomitant procedures. Preoperatively, 3 (3%) had endocarditis. Bicuspid valve was observed in 38 (38.4%). None died at 30 days in the AVN group. The median follow-up duration was 3.2 years. After propensity score matching, the expected survival and freedom from at least moderate aortic regurgitation at 5 years was 91.7% ± 3.1% and 97.6% ± 1.7%, respectively. Propensity score matching yielded 77 patients in each group. The Kaplan-Meier curve demonstrated equivalent survival at 5 years between the 2 groups (P = .95). Additionally, freedom from at least moderate aortic regurgitation was comparable at 5 years (P = .23).

CONCLUSIONS

AVN can be safely performed for a variety of aortic valve diseases, with or without concomitant operations. AVN demonstrated similar midterm outcomes compared with SAVR with a bioprosthetic valve in the United States adult population.

Ex vivo evaluation of 3 different right ventricular outflow tract substitutes

OBJECTIVES

The Ross procedure represents an excellent treatment option in younger patients with aortic stenosis but is limited by poor availability of homografts. In this study, we investigated the hydrodynamic performance of 3 different types of right ventricular outflow tract replacement with pericardium or synthetic material.

METHODS

Three different types of valved conduits were constructed using pericardium and/or synthetic material (Group PEPE: pericardial cusps and pericardial conduit, Group PEPR: pericardial cusps and Dacron conduit, Group PRPR: expanded polytetrafluoroethylene cusps and Dacron conduit). The conduits were designed according to the Ozaki method. Their hydrodynamic performance (effective orifice area, mean pressure gradient and leakage volume) were evaluated in a mock circulation loop at different hydrodynamic conditions.

RESULTS

Hydrodynamic assessment showed significantly larger effective orifice area of PEPE and PEPR compared to PRPR under all conditions and there were no significant differences between PEPE and PEPR [for condition 2: PEPE 2.43 (2.35-2.54) cm2, PEPR: 2.42 (2.4-2.5) cm2, PRPR: 2.08 (1.97-2.21) cm2, adjusted pairwise comparisons: PEPE versus PEPR: P = 0.80, PEPE versus PRPR: P  < 0.001, PEPR versus PRPR: P  < 0.001]. Mean pressure gradient was significantly lower for PEPE and PEPR compared with PRPR, whereas no significant differences were seen between PEPE and PEPR. Leakage volume was significantly lower for PEPE and PEPR compared with PRPR under all conditions while leakage was similar between PEPE and PEPR.

CONCLUSIONS

Pulmonary graft reconstruction with pericardium cusps showed superior hydrodynamic performance compared with polytetrafluoroethylene cusps. Our results suggest that it could be considered as an alternative substitute for right ventricular outflow tract replacement during the Ross procedure.

Aortic valve neocuspidization and bioprosthetic valves: Evaluating turbulence haemodynamics

Aortic valve disease is often treated with bioprosthetic valves. An alternative treatment is aortic valve neocuspidization which is a relatively new reparative procedure whereby the three aortic cusps are replaced with patient pericardium or bovine tissues. Recent research indicates that aortic blood flow is disturbed, and turbulence effects have yet to be evaluated in either bioprosthetic or aortic valve neocuspidization valve types in patient-specific settings. The aim of this study is to better understand turbulence production in the aorta and evaluate its effects on laminar and turbulent wall shear stress. Four patients with aortic valve disease were treated with either bioprosthetic valves (n=2) or aortic valve neocuspidization valvular repair (n=2). Aortic geometries were segmented from magnetic resonance images (MRI), and 4D flow MRI was used to derive physiological inlet and outlet boundary conditions. Pulsatile large-eddy simulations were performed to capture the full range of laminar, transitional and turbulence characteristics in the aorta. Turbulence was produced in all aortas with highest levels occurring during systolic deceleration. In the ascending aorta, turbulence production is attributed to a combination of valvular skew, valvular eccentricity, and ascending aortic dilation. In the proximal descending thoracic aorta, turbulence production is dependent on the type of arch-descending aorta connection (e.g., a narrowing or sharp bend) which induces flow separation. Laminar and turbulent wall shear stresses are of similar magnitude throughout late systolic deceleration and diastole, although turbulent wall shear stress magnitudes exceed laminar wall shear stresses between 27.3% and 61.1% of the cardiac cycle. This emphasises the significance of including turbulent wall shear stress to improve our comprehension of progressive arterial wall diseases. The findings of this study recommend that aortic valve treatments should prioritise minimising valvular eccentricity and skew in order to mitigate turbulence generation.

Considering alternatives to transcatheter heart valves for managing patients with severe aortic valve stenosis

INTRODUCTION

Transcatheter aortic valve implantation (TAVI) is becoming the standard of care for severe symptomatic aortic stenosis (AS). Yet, some patients with AS are not indicated/eligible for TAVI. Several noninvasive, catheter-based or surgical alternatives exist, and other therapeutic options are emerging.

AREAS COVERED

This review provides an overview of non-TAVI options for severe AS. Non-invasive, transcatheter, and alternative surgical strategies are discussed, emphasizing their backgrounds, techniques, and outcomes.

EXPERT OPINION

Alternative therapies to TAVI, whether device-based or non-device-based, continue to evolve or emerge and provide either alternative treatments or a bridge to TAVI, for patients not meeting indications for, or having contraindications to TAVI.Although TAVI and SAVR are the current dominant therapies, there are still some patients that could benefit in the future from other alternatives.Data on alternative options for such patients are scarce. Many advantages and disadvantages arise when selecting a specific treatment strategy for individual patients.Head-to-head comparison studies could guide physicians toward better patient selection and procedural planning. Awareness of therapeutic options, indications, techniques, and outcomes should enable heart teams to achieve optimized patient selection. Furthermore, it can increase the use of these alternatives to optimize the management of AS among different patient populations.

The Ozaki Procedure: Standardized Protocol Adoption of a Complex Innovative Procedure

Background

The Ozaki procedure using autologous pericardium is an interesting but complex alternative for aortic valve replacement. We present a standardized approach to minimize the learning curve and confirm reproducibility.

Methods

After careful preparation, from May 2015 to February 2021, an Ozaki procedure was performed on 46 patients age 51 ± 14 years. Seven had unicuspid (15%), 29 bicuspid (63%), and 10 tricuspid (22%) aortic valves, and 2 patients had endocarditis. Endpoints were operative learning curves, perioperative outcomes, intermediate-term valve hemodynamics, reintervention, health-related quality of life (MacNew Heart Disease Health-Related Quality of Life questionnaire), and mortality.

Results

Cardiopulmonary bypass and aortic clamp times decreased from 145 to 125 ​minutes and 120 to 100 ​minutes, respectively, over the first 20 cases, reflecting the learning curve. There was no major perioperative morbidity or mortality. Median postoperative stay was 6.9 days. Aortic regurgitation was mild or less in all but 2 patients who developed moderate aortic regurgitation. Mean aortic valve gradient was 7.9 mmHg postoperatively, 9.2 mmHg by 6 months, and constant thereafter. Left ventricular ejection fraction was 58% preoperatively, 60% at 6 months, and remained stable thereafter. One patient developed infective endocarditis 7 months postoperatively, failed medical management, and underwent valve replacement at 14 months. Two-year survival was 96%, with 1 noncardiac death at 16 months. Health-related quality of life in mental, physical, and emotional domains was better than matched norms, global 6.2 vs. 5.0 (p < 0.0001).

Conclusions

Using a well-prepared standardized approach, the Ozaki procedure is reproducible with a short learning curve, excellent hemodynamic performance, and good quality of life.

Does the AVNeo valve reduce wall stress on the aortic wall? A cardiac magnetic resonance analysis with 4D-flow for the evaluation of aortic valve replacement with the Ozaki technique

OBJECTIVES

Aortic valve neocuspidalization aims to replace the 3 aortic cusps with autologous pericardium pre-treated with glutaraldehyde, and it is a surgical alternative to the classical aortic valve replacement (AVR). Image-based patient-specific computational fluid dynamics allows the derivation of shear stress on the aortic wall [wall shear stress (WSS)]. Previous studies support a potential link between increased WSS and histological alterations of the aortic wall. The aim of this study is to compare the WSS of the ascending aorta in patients undergoing aortic valve neocuspidalization versus AVR with biological prostheses.

METHODS

This is a prospective nonrandomized clinical trial. Each patient underwent a 4D-flow cardiac magnetic resonance scan after surgery, which informed patient-specific computational fluid dynamics models to evaluate WSS at the ascending aortic wall. The adjusted variables were calculated by summing the residuals obtained from a multivariate linear model (with ejection fraction and left ventricle outflow tract-aorta angle as covariates) to the mean of the variables.

RESULTS

Ten patients treated with aortic valve neocuspidalization were enrolled and compared with 10 AVR patients. The aortic valve neocuspidalization group showed a significantly lower WSS in the outer curvature segments of the proximal and distal ascending aorta as compared to AVR patients (P = 0.0179 and 0.0412, respectively). WSS levels remained significantly lower along the outer curvature of the proximal aorta in the aortic valve neocuspidalization population, even after adjusting the WSS for the ejection fraction and the left ventricle outflow tract-aorta angle [2.44 Pa (2.17-3.01) vs 1.94 Pa (1.72-2.01), P = 0.02].

CONCLUSIONS

Aortic valve neocuspidalization hemodynamical features are potentially associated with a lower WSS in the ascending aorta as compared to commercially available bioprosthetic valves.

Ozaki procedure-re-construction of aortic valve leaflets using autologous pericardial tissue: a review

The Ozaki procedure has emerged as a valuable option for treating various aortic valve pathologies. This review article delves into the intricacies of this innovative surgical approach by exploring its adaptation to the complex anatomy and physiology of the aortic root. The diverse etiologies of aortic valve diseases, ranging from congenital anomalies to degenerative changes, make treatment selection a complex challenge. Aortic valve replacement has traditionally been the gold standard, but emerging evidence supports valve repair techniques, emphasizing the importance of preserving native tissue. Nevertheless, issues like lifelong anticoagulation with mechanical valves and patient-prosthetic mismatch remain. The Ozaki procedure offers a compelling alternative by utilizing autologous pericardium or a tissue substitute to construct new aortic valve leaflets. This technique, standardized by Dr. Ozaki in 2007, provides a customizable and adaptable solution. The article highlights the anatomy of the aortic root, emphasizing the critical role of the sinus of Valsalva and interleaflet triangles in maintaining proper valve function. The procedure's unique adaptation to aortic root dynamics allows for reduced mechanical stress during systole and diastole, mimicking the natural valve's behavior. Furthermore, Ozaki leaflets exhibit promising hemodynamics and reduced risks of complications, such as permanent pacemaker implantation and patient-prosthetic mismatch. The use of autologous pericardium in the Ozaki procedure presents advantages, including enhanced tissue strength, minimal immunogenicity, and reduced risk of immune-mediated calcification. These factors contribute to the longevity and resilience of the reconstructed valve. This comprehensive review aims to shed light on the procedure's intricacies, its alignment with aortic root anatomy and physiology, and its potential as a valuable tool in the armamentarium of aortic surgeons.

Bioprosthetic Valves for Lifetime Management of Aortic Stenosis: Pearls and Pitfalls

This review explores the use of bioprosthetic valves for the lifetime management of patients with aortic stenosis, considering recent advancements in surgical (SAV) and transcatheter bioprostheses (TAV). We examine the strengths and challenges of each approach and their long-term implications. We highlight differences among surgical bioprostheses regarding durability and consider novel surgical valves such as the Inspiris Resilia, Intuity rapid deployment, and Perceval sutureless bioprostheses. The impact of hemodynamics on the performance and durability of these prostheses is discussed, as well as the benefits and considerations of aortic root enlargement during Surgical Aortic Valve Replacement (SAVR). Alternative surgical methods like the Ross procedure and the Ozaki technique are also considered. Addressing bioprosthesis failure, we compare TAV-in-SAV with redo SAVR. Challenges with TAVR, such as TAV explantation and considerations for coronary circulation, are outlined. Finally, we explore the potential challenges and limitations of several clinical strategies, including the TAVR-first approach, in the context of aortic stenosis lifetime management. This concise review provides a snapshot of the current landscape in aortic bioprostheses for physicians and surgeons.

Single center two years' experience of Ozaki procedure: Early follow-up

The Ozaki Procedure is an innovative surgical technique aiming of aortic valve neocuspidization using glutaraldehyde-treated autologous pericardium was first developed by Ozaki et al in 2007. With this newly developed technique, valve replacement was achieved without using prosthetic material due to both aortic stenosis and aortic insufficiency. Between December 2020 and December 2022, a total of 59 patients were operated on with the Ozaki Procedure due to aortic valve pathologies in our center. We evaluated the pre- and postoperative as well as the first-month data of a total of 44 patients with isolated the Ozaki Procedure and compared their echocardiographic changes. Patients with isolated aortic valve pathology were included in the study. Fifteen patients who underwent simultaneous coronary artery bypass surgery and Ozaki Procedure were excluded from the analysis. In the first month after the operation, n:2 (%4.5) patients died. When the preoperative and postoperative 1st month echocardiographic data of the remaining patients were compared, it was found that the decrease in mean gradient, max gradient and peak velocity values in the aortic valve was statistically significant. This is due to the fact that reaching neo-valves has very similar hemodynamics to the native aortic valve. Aortic valve neocuspidization by Ozaki Procedure may be a viable alternative to both surgical aortic valve replacement (AVR) and transcatheter aortic valve implantation. Its popularity and application is increasing all over the world. Short and mid-term results are available in the literature. The short and mid-term results are good, and the long-term results are hopeful.

A Case of Severe Aortic Stenosis after Aortic Valve Neocuspidization Using Autologous Pericardium (Ozaki Procedure)

A 56-year-old man with a history of left nephrectomy for Wilms' tumor on chronic hemodialysis underwent aortic valve neocuspidization using autologous pericardium (Ozaki procedure) for aortic stenosis (AS) due to a bicuspid aortic valve 6 years ago. The AS gradually progressed and a decrease in the left ventricular ejection fraction was observed. Because of this, we decided to perform reoperative aortic valve replacement using a mechanical valve. Intraoperative findings showed severe calcification at the site where the autologous pericardium was sutured to the annulus. However, the degeneration of the valve leaflets themselves was mild. While excellent mid-term results have been reported for the Ozaki procedure, the long-term results are still unclear. In this case, the annulus was severely calcified, which reduced the mobility of the leaflet. We report the first case of AS progression requiring reoperation in the long-term period after the Ozaki procedure.

Predictors of Mid-Term AVNeo Insufficiency

INTRODUCTION

Aortic stenosis (AS) is the most common valvular heart disease and the most common indication for aortic valve replacement in adults. Aortic valve neocuspidization (AVNeo) with fixed autologous pericardium, also known as the Ozaki procedure, is a possible alternative treatment of AS. Autopericardial valves save the dynamics and physiological anatomy of the aortic root, however, the service life of autopericardial leaflets is limited. There is no data about factors that may influence the development of AVNeo insufficiency. Here, we assessed the effect of autopericardial leaflet symmetry on the development of aortic insufficiency after Ozaki procedure.

METHODS

This study included 381 patients with AS who underwent Ozaki procedure. Patients were divided into group 1 (171 patients with symmetric aortic root) and group 2 (210 patients with asymmetric aortic root).

RESULTS

The maximum observation period was up to 65 months. Sixteen cases of aortic insufficiency were detected in group 1, and 33 cases were detected in group 2. Based on the results of Cox regression, the predictors of aortic insufficiency in the late postoperative period are age and asymmetry of neocusps. According to results of Kaplan-Meier analysis, insufficiency of AVNeo in the maximum follow-up period after surgical correction of AS for group 1 patients was significantly lower than for group 2 patients (P=0.006).

CONCLUSION

Asymmetric neocusps increase the risk of aortic insufficiency in the mid-term period after Ozaki procedure. And the older the patients at the time of surgery, the less likely they develop AVNeo insufficiency.

Validation of a laser projection platform for the preparation of surgical patches used in paediatric cardiac surgery

OBJECTIVES

Reconstruction of cardiovascular anatomy with patch material is integral to the repair of congenital heart disease. We present validation of a laser projection platform for the preparation of surgical patches as a proof-of-concept for intraoperative use in patient-specific planning of paediatric cardiac surgery reconstructions.

METHODS

The MicroLASERGUIDE, a compact laser projection system that displays computer-aided designs onto 2D/3D surfaces, serves as an alternative to physical templates. A non-inferiority comparison of dimensional measurements was conducted between laser projection ('laser') and OZAKI AVNeo Template ('template') methods in creation of 51 (each group) size 13 valve leaflets from unfixed bovine pericardium. A digital version of the OZAKI AVNeo Template dimensions served as control. Feasibility testing was performed with other common patch materials (fixed bovine pericardium, PTFE and porcine main pulmonary artery as a substitute for pulmonary homograft) and sizes (13, 23) (n = 3 each group).

RESULTS

Compared to control (height 21.5, length 21.0 mm), template height and length were smaller (height and length differences of -0.3 [-0.5 to 0.0] and -0.4 [-0.8 to -0.1] mm, P < 0.01 each); whereas, both laser height and length were relatively similar (height and length differences of height 0.0 [-0.2 to 0.2], P = 0.804, and 0.2 [-0.1 to 0.4] mm, P = 0.029). Template percent error for height and length was -1.5 (-2.3 to 0.0)% and -1.9 (-3.7 to -0.6)% vs 0.2 (-1.0 to 1.1)% and 1.0 (-0.5 to 1.8)% for the laser. Similar results were found with other materials and sizes. Overall, laser sample dimensions differed by a maximum of 5% (∼1 mm) from the control.

CONCLUSIONS

The laser projection platform has demonstrated promise as an alternative methodology for the preparation of surgical patches for use in cardiac surgery. This technology has potential to revolutionize preoperative surgical planning for numerous congenital anomalies that require patient-specific patch-augmented repair.

Urgent aortic valve neocuspidization using the Ozaki procedure in an infant with native aortic valve endocarditis

Native valve aortic endocarditis is rarely seen in the paediatric population. Although, the first-line of treatment is medical, surgical intervention may be indicated in patients with unrepairable valvular and subvalvular disease. Recently, the aortic valve neocuspidization (AVNeo) procedure has gained popularity both in adult and children in whom other repair techniques are not feasible. In this case report, we present an urgent aortic valve replacement using the AVNeo technique in a critically ill infant with a small annulus, severe left ventricular outflow tract stenosis, and severe aortic regurgitation.

Aortic Valve Replacement with Single-Strip Autologous Pericardium

BACKGROUND

 Aortic valve replacement with mechanical valves is the standard treatment for aortic valve disease in Indonesia. Its usage is associated with high cost, risk of endocarditis and thromboembolic event, and lifetime consumption of anticoagulants. We performed a novel replacement technique of the aortic valve using an autologous pericardium and evaluated the short-term outcomes.

METHODS

 From April 2017 to April 2020, 16 patients underwent aortic valve replacement with a single-strip autologous pericardium. Outcomes of the left ventricular reverse remodeling (LVRR), 6-minute walk test (6MWT), and soluble suppression of tumorigenicity-2 (sST-2) were measured at 6 months postoperation.

RESULTS

 A total of 16 surgeries were performed using aortic valve replacement with single-strip pericardium without conversion to mechanical valve replacement. The patients included eight males and eight females, and the mean age was 49.63 ± 12.54 years. The most common diagnosis was mixed aortic valve stenosis and regurgitation (9 cases). Five patients underwent a concomitant coronary artery bypass graft (CABG) procedure and 12 patients underwent either mitral or tricuspid valve repair. The mean aortic cross-clamp time was 139.88 ± 23.21 minutes and cardiopulmonary bypass time was 174.37 ± 33.53 minutes. At 6 months postoperation, there was an increase in the distance walked at the 6MWT (p = 0.006) and a decrease of the sST-2 level (p = 0.098). Echocardiogram showed two patients had LVRR. Survival and freedom from reoperation are 100% at 1 year of follow-up.

CONCLUSION

 Aortic valve replacement with a single strip of pericardium is a good alternative to aortic valve replacement with a mechanical valve. Short-term evaluation at 6 months postoperation showed improvement in clinical status and echocardiographic parameters compared to baseline.

In Vitro Proof of Concept of a First-Generation Growth-Accommodating Heart Valved Conduit for Pediatric Use

Currently available heart valve prostheses have no growth potential, requiring children with heart valve diseases to endure multiple valve replacement surgeries with compounding risks. This study demonstrates the in vitro proof of concept of a biostable polymeric trileaflet valved conduit designed for surgical implantation and subsequent expansion via transcatheter balloon dilation to accommodate the growth of pediatric patients and delay or avoid repeated open-heart surgeries. The valved conduit is formed via dip molding using a polydimethylsiloxane-based polyurethane, a biocompatible material shown here to be capable of permanent stretching under mechanical loading. The valve leaflets are designed with an increased coaptation area to preserve valve competence at expanded diameters. Four 22 mm diameter valved conduits are tested in vitro for hydrodynamics, balloon dilated to new permanent diameters of 23.26 ± 0.38 mm, and then tested again. Upon further dilation, two valved conduits sustain leaflet tears, while the two surviving devices reach final diameters of 24.38 ± 0.19 mm. After each successful dilation, the valved conduits show increased effective orifice areas and decreased transvalvular pressure differentials while maintaining low regurgitation. These results demonstrate concept feasibility and motivate further development of a polymeric balloon-expandable device to replace valves in children and avoid reoperations.

Managing the challenge of a small aortic annulus in patients with severe aortic stenosis

INTRODUCTION

Small aortic annulus (SAA) poses a challenge in the management of patients with severe aortic stenosis requiring aortic valve replacement - both surgical and transcatheter - since it has been associated with worse clinical outcomes.

AREAS COVERED

This review aims to comprehensively summarize the available evidence regarding the management of aortic stenosis in patients with SAA and discuss the current controversies as well as future perspectives in this field.

EXPERT OPINION

It is paramount to agree in a common definition for diagnosing and properly treating SAA patients, and for that purpose, multidetector computer tomography is essential. The results of recent trials led to the expansion of transcatheter aortic valve replacement among patients of all the surgical-risk spectrum, and the choice of treatment (transcatheter, surgical) should be based on patient comorbidities, anatomical characteristics, and patient preferences.

Application of compression optical coherence elastography for characterization of human pericardium: A pilot study

The recent impressive progress in Compression Optical Coherence Elastography (C-OCE) demonstrated diverse biomedical applications, comprising ophthalmology, oncology, etc. High resolution of C-OCE enables spatially resolved characterization of elasticity of rather thin (thickness < 1 mm) samples, which previously was impossible. Besides Young's modulus, C-OCE enables obtaining of nonlinear stress-strain dependences for various tissues. Here, we report the first application of C-OCE to nondestructively characterize biomechanics of human pericardium, for which data of conventional tensile tests are very limited and controversial. C-OCE revealed pronounced differences among differently prepared pericardium samples. Ample understanding of the influence of chemo-mechanical treatment on pericardium biomechanics is very important because of rapidly growing usage of own patients' pericardium for replacement of aortic valve leaflets in cardio-surgery. The figure demonstrates differences in the tangent Young's modulus after glutaraldehyde-induced cross-linking for two pericardium samples. One sample was over-stretched during the preparation, which caused some damage to the tissue.

Aortic Valve Reconstruction With Autologous Pericardium Versus a Bioprosthesis: The Ozaki Procedure in Perspective

Background We assessed the Ozaki procedure, aortic valve reconstruction using autologous pericardium, with respect to its learning curve, hemodynamic performance, and durability compared with a stented bioprosthesis. Methods and Results From January 2007 to January 2016, 776 patients underwent an Ozaki procedure at Toho University Ohashi Medical Center. Learning curves, aortic regurgitation (AR), and peak gradient, assessed by serial echocardiograms, valve rereplacement, and survival were investigated. Valve performance and durability were compared with 627 1:1 propensity-matched patients receiving stented bovine pericardial valves implanted from 1982 to 2011 at Cleveland Clinic. Learning curves were observed for aortic clamp and cardiopulmonary bypass times, AR prevalence, and early mortality. Decreased aortic clamp time was observed over the first 300 cases. New surgeons performing parts of the procedure after case 400 resulted in a slight increase in aortic clamp and cardiopulmonary bypass times. Among matched patients, the Ozaki cohort had more AR than the PERIMOUNT cohort (severe AR at 1 and 6 years, 0.58% and 3.6% versus 0.45% and 1.0%, respectively; P[trend]=0.006), although with a steep learning curve. Peak gradient showed the opposite trend: 14 and 17 mm Hg for Ozaki and 24 and 28 mm Hg for PERIMOUNT at these times (P[trend]<0.001). Freedom from rereplacement was similar (P=0.491). Survival of the Ozaki cohort was 85% at 6 years. Conclusions Patients undergoing the Ozaki procedure had lower gradients but more recurrent AR than those receiving PERIMOUNT bioprostheses. Although recurrent AR is concerning, results confirm low risk and good midterm performance of the Ozaki procedure, supporting its continued use.

Aortic valve neocuspidization using the Ozaki technique: A meta-analysis of reconstructed patient-level data

BACKGROUND

Aortic valve neocuspidization using the Ozaki technique has shown promising results both in adults and children.

METHODS

A systematic search of the PubMed and Cochrane databases was performed up to November 13, 2021. Individual patient data were reconstructed and analyzed from the Kaplan-Meier curves of all eligible studies for time-to-event outcomes.

RESULTS

We included a total of 22 studies reporting on 1,891 patients that underwent Ozaki reconstruction. Mean age at the time of surgery was 43.2 ± 24.5 years (65 ± 12.3 years for adult patients and 12.3 ± 3.8 years for pediatric patients). The most common indication was aortic stenosis (46.4%, 95% CI 34.1-58.6). Mean cross-clamp and cardiopulmonary bypass duration were 106.8 ± 24.8 minutes and 135.2 ± 35.1 minutes, respectively. Permanent pacemaker was implanted in 0.7% (95% CI 0.4-1.2) of the patients. At discharge, mean effective orifice area was 2.1 ± 0.5 cm²/m². At latest follow-up, peak gradient was 15.7 ± 7.4 mm Hg and only 0.25% (95% CI 0-2.3) had moderate aortic insufficiency. In-hospital mortality was 0.7% (95% CI 0.1-1.7). Late mortality was 1.9% during a mean follow-up of 38.1 ± 23.8 months. One-year, 3-year, and 5-year freedom from reoperation rates were 98.0 %, 97.0 % and 96.5%, respectively. More than half of the reoperations were due to infective endocarditis (51.5%, 95% CI 18.3-84.0). In our cohort, the risk of endocarditis per patient per year was 0.5%.

CONCLUSIONS

The midterm outcomes of the Ozaki procedure are excellent in terms of hemodynamics, survival, and freedom from reoperation. Acquiring long-term follow-up will help solidify this technique in the cardiac surgery armamentarium.

Aortic valve neocuspidization using autologous versus bovine pericardium: Ozaki versus Batista

BACKGROUND

The average living age of the population is constantly increasing and so is the incidence and prevalence of aortic valve disease. Surgical aortic valve replacement (SAVR) is the current gold standard treatment. Nevertheless, the use of prosthetic valves in SAVR is associated with issues that impact patients' quality of life. Aortic valve neocuspidization (AV Neo) offers a means to solve this dilemma by minimizing foreign valve tissue. AV Neo can either be performed using glutaraldehyde-treated autologous pericardium (Ozaki procedure) or bovine pericardium (Batista procedure).

AIMS

This commentary aims to discuss the recent study by Chan and colleagues which highlighted the surgical approach, clinical outcomes, and limitations of the Ozaki procedure, and compare this to the Batista procedure.

METHODS

A comprehensive literature search was performed using multiple electronic databases including PubMed, Ovid, Embase, and Scopus to collate the relevant research evidence.

RESULTS

Although the Ozaki procedure can achieve favorable results whilst mainly avoiding the need for life-long oral anticoagulation with mechanical valves, it still has several limitations that may hinder results. AV Neo using glutaraldehyde-treated bovine pericardium, developed by pioneer cardiac surgeon Dr. Randas J. Vilela Batista, yields superior clinical outcomes to Ozaki's, including excellent survival, lower complications, and minimal need for reoperation as well as shorter operative times.

CONCLUSION

AV Neo offers a means to perform SAVR whilst escaping the prosthetic valve issues. However, the Batista procedure has shown beyond doubt that it can be considered the superior approach for AV Neo over the Ozaki procedure.

AVNeo improves early haemodynamics in regurgitant bicuspid aortic valves compared to aortic valve repair

OBJECTIVES

Calcified or fibrotic cusps in patients with bicuspid aortic valves and aortic regurgitation complicate successful aortic valve (AV)-repair. Aortic valve neocuspidization (AVNeo) with autologous pericardium offers an alternative treatment to prosthetic valve replacement. We compared patients with regurgitant bicuspid valves undergoing AV-repair or AVNeo.

METHODS

We retrospectively analysed patients with regurgitant bicuspid valves undergoing AV-repair or AVNeo. We focused on residual regurgitation, pressure gradients and effective orifice area, determined preoperatively and at discharge.

RESULTS

AV-repair was performed in 61 patients (mean age: 43.2 ± 11.3 years) and AVNeo in 22 (45.7 ± 14.1). Prior to the operation patients of the AV-repair group showed severe regurgitation in 38 cases (62.3%) and moderate in 23 (37.6%); in the AVNeo group, all patients exhibited severe regurgitation. Postoperatively, 57 patients (93.4%) patients had no or mild regurgitation after AV-repair and 21 (95.4%) after AVNeo. In AVNeo-patients, peak (10.6 ± 3.1 mmHg vs 22.7 ± 11 mmHg, P< 0.001) and mean pressure gradients (5.9 ± 2 mmHg vs 13.8 ± 7.3 mmHg, P < 0.001) were significantly lower and the orifice area significantly larger (2.9 ± 0.8 cm2 vs 1.9 ± 0.7 cm2, P < 0.001) compared to repair.

CONCLUSIONS

Compared to AV-repair, patients AVNeo showed lower mean pressure gradients and larger orifice areas at discharge. The functional result was not different.

Physiological Ventricular Simulator for Valve Surgery Training

Surgical simulation is becoming increasingly important in training cardiac surgeons. However, there are currently no training simulators capable of testing the quality of simulated heart valve procedures under dynamic physiologic conditions. Here we describe a dynamic ventricular simulator, consisting of a 3D printed valve suspension chamber and a model 1423 Harvard apparatus pulsatile pump, which can provide close to physiologic hemodynamic perfusion of porcine aortic roots attached to the valve chamber for education and training in cardiac surgery. The simulator was validated by using it to test aortic valve leaflet repairs (n = 6) and aortic valve replacements (n = 3) that were performed by two trainees. Procedural success could be evaluated by direct visualization of the opening and closing valve, hemodynamic measurements and echocardiography. We conclude that, unlike other methods of simulation, this novel ventricular simulator is able to test the functional efficacy of aortic procedures under dynamic physiologic conditions using clinically relevant echocardiographic and hemodynamic outcomes. While validated for valve surgery, other potential applications include ascending aortic interventions, coronary re-implantation or catheter-based valve replacements.

Rapid anticalcification treatment for glutaraldehyde-fixed autologous tissue in cardiovascular surgery

Background

Glutaraldehyde (GA)-fixed autologous tissues, including the pericardium, are widely used as patches and valve substitutes in cardiovascular surgery. However, GA treatment causes tissue calcification. No rapid anticalcification method has been established for use during surgery. Here, we aimed to establish a rapid anticalcification method using ethanol, as has already been demonstrated for bioprosthetic valves.

Methods

Thoracic aorta tissues were first fixed with GA for 3 min and then treated with ethanol for 0 (group 2), 10 (group 3), 20 (group 4), and 30 (group 5) min; untreated tissues (group 1) served as the control. The treated tissues were subdermally implanted into 3-week-old male Wistar rats and kept in place for 28 days. The calcification in each explant was semiquantitatively evaluated by annotating and measuring the area using virtual slides, and the data obtained were statistically analyzed.

Results

Semiquantitative analysis revealed that calcification of the implants from the untreated group (group 1; P = 0.0014) and groups 4 (P = 0.0014) and 5 (P = 0.0031) was significantly lower than that of implants from group 2. Moreover, implants from group 3 showed a tendency toward decreased calcification, although it was not significant (P = 0.0503).

Conclusions

A rapid ethanol treatment prevents calcification of GA-fixed tissues in a rat model of subdermal implantation. This method may facilitate effective and rapid anticalcification of autologous tissues for use during cardiovascular surgery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-022-01895-7.

Aortic valve neocuspidization: Frequently asked technical questions

Since the first description by Professor Ozaki in 2011, more than 5500 aortic valve neocuspidization procedures have been performed worldwide, with promising short- and mid-term outcomes. We here report the nuances required to master this highly reproducible, standardized technique for the treatment of aortic valve disease.

Aortic valve neocuspidization and its technical nuance

Aortic valve neocuspidization or Ozaki procedure represents an advanced surgical strategy for the management of patients with aortic valvulopathy. It has been shown to have clinical and hemodynamic outcomes that compare favorably with aortic valve replacement as it restores physiological aortic valve function and left ventricular remodeling. There are, however, a new set of issues including structural valve deterioration, leaflet tear/perforation, and need for reoperation. A keen understanding of the technical nuances involved with the Ozaki procedure may help in reducing the incidence of such adverse outcomes.

Single leaflet reconstruction in paediatric aortic regurgitation using the Ozaki procedure

OBJECTIVES

Aortic valve repair in children is still a challenge. The aim of this study was to analyse the surgical results of children with aortic regurgitation who underwent single leaflet reconstruction using the Ozaki procedure in our medical centre.

METHODS

A retrospective study was conducted of nine children with aortic regurgitation who received single leaflet reconstruction from May 2017 to September 2019. Paired t-tests and Wilcoxon signed rank tests were used to compare the data at different time points.

RESULTS

The median surgical age was 4.7 (3.5, 6.4) years. Eight patients were pre-operatively diagnosed with severe aortic regurgitation, while one had moderate regurgitation. The left ventricles were significantly enlarged, with an average z-score of 3.8. Single leaflet reconstruction was carried out using glutaraldehyde-treated autologous pericardium under the standard Ozaki procedure. The median follow-up was 22 (14, 33) months. There was no post-operative death or re-intervention. One patient had moderate or more aortic regurgitation during the follow-up. The average degree of aortic regurgitation was mild, and the average z-score of the left ventricle decreased to -0.2 in the last follow-up.

CONCLUSIONS

Single leaflet reconstruction using the Ozaki procedure was an effective surgical method for treating children with aortic regurgitation in our centre with satisfactory short-term results.

Standardized Aortic Valve Neocuspidization for Treatment of Aortic Valve Diseases

BACKGROUND

Aortic valve replacement is the traditional surgical treatment for aortic valve diseases, yet standardized aortic valve neocuspidization (AVNeo) is a promising alternative that is gaining popularity. The purpose of this article is to review the available published literature of AVNeo using glutaraldehyde-treated autologous pericardium, also known as the Ozaki procedure, including indications, outcomes, potential benefits, and modes of failure for the reconstructed valve.

METHODS

A comprehensive literature search was performed using keywords related to aortic valve repair, AVNeo, or Ozaki procedure. All articles describing performance of AVNeo were reviewed.

RESULTS

Reported early mortality after AVNeo varies from 0% to 5.88%. The largest cohort of patients in the literature includes 850 patients with an inhospital mortality rate of 1.88%. Cumulative incidence of aortic valve reoperation was 4.2% in the largest series. Reoperation was uncommon and mainly due to infective endocarditis or degeneration of the reconstructed valve (most commonly due to aortic valve regurgitation, rather than stenosis).

CONCLUSIONS

Aortic valve neocuspidization is a versatile and standardized alternative to aortic valve replacement with a biological prosthesis. Early to midterm outcomes from a number of centers are excellent and demonstrate the safety and durability of the procedure. Long-term outcomes and clinical trial data are necessary to determine which patients benefit the most from this procedure.

Repair of Gerbode defect and aortic neocuspidization by using bovine pericardium in aortic valve endocarditis

Aortic valve endocarditis may be destructive and cause an acquired Gerbode-type defect. The use of biological material in the closure of the Gerbode defect and reconstruction of the aortic valve is essential for both early and long-term survival. Herein, we present a 62-year-old male patient whose Gerbode defect was repaired with bovine pericardium. Additionally, the aortic valve was reconstructed by using bovine pericardium with Ozaki neocuspidization technique.

Low-Risk Surgical Aortic Valve Replacement in the Era of Transcatheter Aortic Valve Implantation

Open surgical aortic valve replacement (SAVR) is a viable alternative to transcatheter implantation in low-risk patients. In this light, we evaluated the safety and effectiveness of SAVR performed through conventional and less invasive surgical approaches in a high-volume center.

We retrospectively reviewed the records of 395 consecutive patients who underwent open SAVR from January 2019 through December 2019 in our center. We evaluated and compared the operative results and postoperative major adverse outcomes of 3 surgical approaches: full median sternotomy (n=267), upper ministernotomy (ministernotomy) (n=106), and right anterior thoracotomy (minithoracotomy) (n=22).

Overall, the 30-day all-cause mortality rate was 0.8% (3 patients). Stroke occurred in 8 patients (2%), disabling stroke in 4 patients (1%), myocardial infarction in 1 (0.2%), and surgical site infection in 13 (3.2%). There was no difference in 30-day mortality rate or incidence of postoperative major adverse events among the 3 surgical groups. Stroke and surgical site infection occurred more frequently, but not significantly so, in the full-sternotomy group. The mean hospital stay was longer after full sternotomy (9.1 ± 5.5 d) than after ministernotomy (7.5 ± 2.9 d) or minithoracotomy (7.4 ± 1.9 d) (P=0.012).

Our findings suggest that open SAVR performed in a high-volume center is associated with a low early mortality rate and that less invasive approaches result in faster postoperative recovery and shorter hospital stays.

Impact of valvuloarterial impedance on left ventricular reverse remodeling after aortic valve neocuspidization

Background

Aortic valve neocuspidization (AVNeo) has emerged as a promising aortic valve procedure, and is expected to have a larger effective orifice area (EOA) than commercially available bioprostheses. It is, however, unclear which indices could facilitate left ventricular (LV) reverse remodeling after AVNeo. The aim of this study is to verify the impact of global left ventricular afterload on the LV reverse remodeling following AVNeo.

Methods

Data-available consecutive 38 patients (median age, 77; interquartile range, 72.8–82.0) undergoing AVNeo for severe aortic stenosis were enrolled in this study. Preoperative and the last follow-up echocardiographic data were retrospectively analyzed including the valvuloarterial impedance (Zva), a marker of global LV afterload. Reduction in LV geometry index (LVGI) and relative wall thickness (RWT) were used as an indicator for LV reverse remodeling.

Results

The Zva reduced in 24 patients (63.2%) during the follow-up period (median, 12 months). Reduction in Zva significantly correlated to improvement of LV geometry (LVGI (r = 0.400, p = 0.013) and RWT (r = 0.627, p < 0.001)), whereas increase in EOA index did not significantly correlate to LVGI (r = 0.009, p = 0.957), or RWT (r = 0.105, p = 0.529)). The reduction in Zva was the multivariate predictor of LV reverse remodeling.

Conclusions

Low global LV afterload led to significant LV reverse remodeling even after AVNeo, which could achieve better valve performance than the conventional bioprostheses.

OUP accepted manuscript

Association between hypoplastic left heart syndrome and valvular pulmonary stenosis is very rare. Severity of valvular pulmonary stenosis in this setting limits management options. Consequently, patients with this condition are considered poor candidates for Norwood stage one reconstruction. Herein, we describe a newborn with hypoplastic left heart syndrome and significantly dysplastic pulmonary valve who successfully underwent the Norwood procedure with neoaortic valve reconstruction. Therefore, the Norwood procedure with neoaortic valve reconstruction might be an option for this difficult condition.

Short-term outcomes of aortic valve neocuspidization for various aortic valve diseases

Objectives

Bioprosthetic valve deterioration remains a major limitation following aortic valve replacement. Favorable results have been reported with an autologous pericardium aortic valve neocuspidization.

Methods

Seventy patients (31 women and 39 men) (mean age, 62 ± 12 years) with aortic stenosis (n = 52 [74%]) or aortic regurgitation (n = 18 [26%]) underwent the aortic valve neocuspidization procedure. Thirty-four patients (49%) had a tricuspid valve, 35 (50%) had a bicuspid valve, and 1 (1%) had a monocuspid valve. European System for Cardiac Operative Risk Evaluation and Society of Thoracic Surgeons scores were, respectively, 2.2% ± 2% and 2.0% ± 1.8%. Four patients (6%) had active endocarditis and 2 (3%) had endocarditis sequelae. One patient (1%) had fibroelastoma. A combined procedure was performed in 33 patients (46%).

Results

The follow-up period was 24 ± 12 months. One patient (1%) died in hospital and 1 patient (1%) underwent conventional valve replacement for significant aortic regurgitation. Postoperative peak and mean pressure gradients were respectively 14 ± 5 and 8 ± 3 mm Hg. Aortic valve area was 2.5 ± 0.6 cm². During follow-up, no patients died. Reintervention occurred in 2 patients (3%). At last follow-up, peak pressure gradient was 13 ± 7 mm Hg, mean pressure gradient was 7 ± 4 mm Hg, and aortic valve area was 2.3 ± 0.7 cm². There was 1 recurrence of moderate aortic stenosis (1%). All patients were in New York Heart Association functional class I (90%) or II (10%). Freedom from major valve-related events was 92.1%, (98.5% for death, 95.2% for reintervention, and 95.2% for endocarditis).

Conclusions

In our experience, the midterm outcomes of the aortic valve neocuspidization procedure with autologous glutaraldehyde fixed pericardium were acceptable for survival, operative risk and valve-related complications, for our all-comer patient population with various aortic valve diseases.