Repair Replacement Research Articles

P96 NO PATIENT SELECTION IN TOTALLY ENDOSCOPIC ISOLATED MITRAL VALVE SURGERY: OPERATIVE AND EARLY RESULTS IN DEGENERATIVE MITRAL VALVE REGURGITATION

Abstract Background and aim In high–volume centers MICS can be offered to any patient affected by degenerative mitral valve surgery (MVS). Aim of this study was to evaluate early outcomes in patients undergoing isolated MVS for degenerative mitral regurgitation (MR) using a totally endoscopic technique. Methods From January 2018 to December 2022, 1124 consecutive unselected patients underwent endoscopic MVS at our institution. Among them, 399 patients underwent isolated MVS for degenerative valve pathology. Concomitant surgery and different etiology were excluded. All patients were approached with peripheral cannulation, limited skin incision (peri–areolar/sub–mammary/anterior axillary line) and 5 mm 30° endoscope. Neo–chordae implantation plus annuloplasty ring was the preferred technique for mitral repair. Results Endoscopic MVS was achieved in all patients and no conversion to sternotomy was needed. Median Cross–Clamp and CPB Time were respectively 93 [75 – 11] and 143 minutes [115 – 171]. Overall in hospital mortality was 0.75%. Major Stroke occurred in 1.6%. Replacement for unsuccessful repair occurred in 4 patients (1%). Repeated cross–clamp for residual MR in 13 patients (3,3%). Median intubation time was 5 h [3 – 7], ICU time was 18 h [15 – 21], bleeding requiring revision occurred in 21 patients (5.3%) always through the same access. PM implantation occurred in 3%, vascular complications in 1%. We had 1 case of endocarditis, 1 case of early failure, 1.3% mitral redo. Conclusions In high volume centers isolated endoscopic MVS without preoperative patient selection has proven to be safe with optimal mortality, good fast–track and low incidence of complications.

Modelling two-dimensional chloride diffusion in repaired RC structures for sustainable maintenance management

Both public and private infrastructure management agencies are responsible for chloride-related corrosion damage to coastal reinforced concrete (RC) structures, which often requires extensive repairs. These repairs are intended to provide serviceability and safety while reducing costs and environmental impact. While there are many repair methods, techniques, and materials available, little is known about their long-term performance and durability. This study examines two-dimensional chloride ingress into square cross section RC columns and their durability using cover replacement techniques with several shapes, thicknesses, locations, and repair times. First, a two-dimensional repair model is developed to simulate these repair strategies and predict their serviceability performance. Two orthogonal concrete replacement strategies (OCR1 and OCR2) and one circular concrete replacement strategy (CCR3) are studied. Next, a method to evaluate and compare maintenance strategies in terms of durability, cost, and environmental impact is also considered. The results of this study reveal that the corners of a column are the most critical areas to evaluate chloride concentration when predicting the time of corrosion initiation and estimating repair time. For long-term maintenance management, the circular concrete replacement strategy is recommended over orthogonal concrete replacement for repair of RC columns exposed to chloride-induced corrosion. The CCR3 strategy requires fewer repairs and achieves higher cost-effectiveness and sustainability compared to the other strategies.

A REPAIR REPLACEMENT PROBLEM FOR COLD STANDBY SYSTEM USING ALPHA SERIES AND GEOMETRIC PROCESS

The present paper studies a cold standby repairable system consisting of two identical components namely component 1, component 2 and onerepairman is studied. Assume that each component after repair is not 'as good as new' and also the successive working times form a decreasing a-series process, the successive repair time's form an increasing geometric process and both the processes are exposing to exponential failure law. Under these assumptions we study an optimal replacement policy N in which we replace the system when the number of failures of component 1 reaches N. It can be determined that an optimal repair replacement policy N* such that the long run average cost per unit time is minimized. It can also be derived an explicit expression of the long-run average cost and the corresponding optimal replacement policy N* can be determined analytically. Numerical results are provided to support the theoretical results

An Imperfect Repair Model with Delayed Repair under Replacement and Repair Thresholds

Based on the extended geometric process, a repair replacement model of a degradation system is studied, in which the delayed repair time depends on the working time after the last repair. Replacement and repair thresholds describe when the system will be replaced and when the system can be repaired, respectively. Two kinds of replacement policies are studied. One policy is jointly determined by the moment of the Nth failure and the first hitting time of the working time after the last repair for the replacement threshold, and the system is replaced, whichever occurs first; the other is the special case of the first policy, and the system is replaced when the working time after the last repair first hits the replacement threshold. The exact expressions of the long-run average cost rate are obtained. The optimal policies exist and can be ascertained by numerical methods. Finally, numerical examples are presented to demonstrate the application of the results obtained in the paper.

Beyond the 10-Year Horizon: Mitral Valve Repair Solely With Chordal Replacement and Annuloplasty

BackgroundThe long-term outcomes of mitral valve repair by nonresection techniques, such as annuloplasty and chordal replacement, for degenerative mitral valve regurgitation were investigated. MethodsAll consecutive patients with degenerative mitral regurgitation who received solely chordal replacement and annuloplasty for mitral valve repair between 2003 and 2010 at the German Heart Center Munich were reviewed. The endpoints of this retrospective study were survival, cumulative incidence of reoperation on the mitral valve, and cumulative incidence of significant recurrent mitral regurgitation. ResultsA total of 346 patients were evaluated. The median follow-up period was 10.86 (range, 0.01-15.86) years. The 30-day mortality rate was 0.58% (n = 2 of 346), whereas the 5-year survival was 92.97% ± 1.41%. At 5 years, cumulative incidence of recurrent mitral regurgitation was 6.87% ± 1.57% and cumulative incidence of reoperation on the mitral valve was 3.69% ± 1.05%. Survival at 10 years was 83.35% ± 2.15%. At 10 years, cumulative incidence of recurrent mitral regurgitation was 13.31% ± 2.22% and cumulative incidence of reoperation was 7.84% ± 1.55%. Cox regression analysis identified age, diabetes mellitus, and reduced left ventricular ejection fraction <55% as independent risk factors for death. Left ventricular ejection fraction <55% was revealed as independent risk factor for significant recurrent mitral regurgitation. ConclusionsThis study demonstrated excellent long-term outcomes with low incidence of reoperation after mitral valve repair using chordal replacement in a highly selected patient cohort. Our findings emphasized the importance of early intervention in severe degenerative mitral regurgitation, especially in patients with reduced left ventricular ejection fraction.

Selective sinus replacement for aortic root repair in bicuspid aortopathy

ObjectivesTo evaluate the results after selective sinus replacement (SSR) for aortic root remodeling in bicuspid aortopathy. MethodsAmong 662 patients who underwent root repair using SSR between 2005 and 2020, there were 114 with bicuspid aortopathy. SSR was performed either as an isolated procedure (31) or as an adjunct to aortic valve repair (83) and was adjusted to the existing aortic annulus diameter rather than a downsized diameter. In valves with asymmetrical commissural orientation, the repair aimed for the achievement of a 180°-commissural orientation. ResultsAbolishment of aortic insufficiency (AI) ≥2+ using root repair alone was only possible in 2 patients with acute-dissection-related AI, yet isolated root repair was also performed in 29 further patients with no/mild AI. All remaining patients with AI ≥2+ presented cusp-related regurgitation and necessitated an additional valve repair. During the mean follow-up of 91 months (range, 13-196), a relevant valve defect (AI ≥3+ in 8, stenosis in 2) occurred in 10 patients (all after combined repair) resulting in an estimated freedom from a relevant aortic valve defect and/or reoperation of 96 ± 2%, 89 ± 4%, and 82 ± 6% at 5, 10, and 12 years, respectively. Echocardiographically, no patient revealed a considerable change of form or size of the repaired root nor was any root reintervention necessary. ConclusionsPatient-tailored root repair using SSR is a very effective and durable valve-sparing approach for bicuspid aortopathy. Aortic cusp repair is decisive for both abolishment of AI in bicuspid aortopathy and for the functional durability of the repaired aortic valve.

Early outcomes of aortic valve repair versus replacement for aortic regurgitation: a single-center experience

BackgroundAortic valve repair in rheumatic patients is not well-studied. We aimed to present our initial Egyptian experience in the aortic valve repair and compare it with the aortic valve replacement. The study included 85 patients who had an aortic valve surgery for aortic regurgitation (AR) in a single center from 2018 to 2020. We assigned the patients to either aortic valve repair (n= 39) or aortic valve replacement (n= 46). Fifty-nine patients (69.4%) had rheumatic heart disease. Study outcomes were hospital complications and the degree of aortic regurgitation after 6 months in patients who had aortic valve repair.ResultsPatients who had replacement were significantly older (49.6± 7.2 vs. 43.8± 8.6 years: P= 0.002) and had more advanced New York Heart Association (P<0.001) and Canadian Cardiovascular Scoring (P= 0.03) classes. Hypertension (31 (67.4%) vs. 17 (43.6%); P= 0.03) and hypercholesteremia (18 (40%) vs. 17 (18.9%); P= 0.04) were more common in the replacement group. Patients who had replacement had a significantly higher percentage of valve retraction (P<0.001). Cardiopulmonary bypass (54.5 (49.5–60) vs. 45 (41–49) min; P<0.001) and ischemic times (36.5 (31–40) vs. 30 (28–33) min; P<0.001) were longer in patients who had an aortic valve replacement. Blood transfusion (28 (60.9%) vs. 11 (282%); P= 0.003) and ICU stay (24.5 (24–48) vs 23 (20–31) h; P= 0.01) were higher in the replacement group. Hospital mortality was non-significantly different between groups. Four patients had trivial AR (10.3%), and six had mild AR (15.4%) in the repair group. There was no difference in valve pathology or outcomes in aortic valve repair patients for degenerative versus rheumatic pathologies. After a 6-month follow-up, four patients had trivial AR (10.3%), and six patients had mild AR (15.4%) in the repair group.ConclusionsAortic valve repair could be an alternative to replacement in selected patients with rheumatic heart disease. Shorter cardiopulmonary bypass and ischemic times may improve repair outcomes compared to replacement.

Impact of aortic root repair or replacement in severe destructive aortic valve endocarditis with paravalvular abscesses on long-term survival.

OBJECTIVESSurgical treatment of destructive infective endocarditis consists of extensive debridement followed by root repair or replacement. However, it remains unknown whether 1 is superior to the other. We aimed to analyse whether long-term results were better after root repair or replacement in patients with root endocarditis.METHODSA total of 148 consecutive patients with root endocarditis treated with surgery from 1997 to 2020 at our department were included. Patients were divided into 2 groups: aortic root repair (n = 85) or root replacement using xenografts or homografts (n = 63).RESULTSPatients receiving aortic root repair showed significantly better long-term survival compared to patients receiving aortic root replacement (log-rank: P = 0.037). There was no difference in terms of freedom from valvular reoperations among both treatment groups (log-rank: P = 0.58). Patients with aortic root repair showed higher freedom from recurrent endocarditis compared to patients with aortic root replacement (log-rank: P = 0.022). Patients with aortic root repair exhibited higher event-free survival (defined as a combination end point of freedom from death, valvular reoperation or recurrent endocarditis) compared to patients receiving aortic root replacement (log-rank: P = 0.022). Age increased the risk of mortality with 1.7% per year. Multi-variable adjusted statistical analysis revealed improved long-term event-free survival after aortic root repair (hazards ratio: 0.57, 95% confidence interval: 0.39–0.95; P = 0.031).CONCLUSIONSAortic root repair and replacement are feasible options for the surgical treatment of root endocarditis and are complementary methods, depending on the extent of infection. Patients with less advanced infection have a more favourable prognosis.Clinical trial registrationUN4232 382/3.1 (retrospective study).

Mitral valve repair for myxomatous mitral regurgitation; Respect or Resect

Background: The superiority of mitral repair using resection of the posterior leaflet versus neo-artificial chordea is still debatable. The objective of this study was to compare leaflet resection versus chordal replacement for mitral valve repair in patients with isolated myxomatous degeneration of the posterior mitral valve leaflet. &#x0D; Methods: This study was conducted on 199 patients with severe symptomatic mitral regurgitation due to myxomatous mitral valve degeneration. Patients were grouped into two groups: Group (1): Respect technique which included 76 patients who had limited resection of the anterior leaflet, chordal transfer, and replacement of anterior leaflet chordae by polytetrafluoroethylene sutures, and placement of annuloplasty ring. Group (2): Resect technique included 123 patients where the operation was done by resecting the prolapsed mid scallop of the posterior leaflet and placement of flexible annuloplasty ring.&#x0D; Results: There was no difference between both groups regarding gender. Patients in the Respect group were younger (37 (25th- 75th percentiles: 29- 44) vs. 54 (48- 60) years, P&lt;0.001). The minimally invasive approach was more commonly used in patients who had resection techniques (20 (26.32%) vs. 106 (86.18%); P&lt;0.001). Ischemic (99 (95- 106) vs. 79 (75- 82); P&lt;0.001) and cardiopulmonary bypass times (134.5 (130- 138.5) vs. 99 (97- 104) min; P&lt;0.001) were higher in the Respect group. Blood loss was more in the Resect group (370 (305- 390) vs. 550 (490- 600) ml; P&lt;0.001). There were no differences in the postoperative complications between groups. ICU stay was longer in patients in the Resect group (5 (5- 6) vs. 7 (6- 8) days; P&lt;0.001). Mitral valve gradient after 12 months was significantly higher in the Resect group (3 (3- 3.5) vs. 4 (3- 5) mmHg; P&lt;0.001). Mitral valve reoperation was required more in patients in the Respect group (5 (6.58%) vs. 1 (0.81%); P= 0.03).&#x0D; Conclusions: Both Respect and resect techniques for mitral valve repair had comparable outcomes and durability. The repair technique should be tailored according to the mitral valve pathology.

Leaflet fusion length is associated with aortic dilation and flow alterations in non-dysfunctional bicuspid aortic valve.

Bicuspid aortic valve (BAV), the most common congenital valve defect, is associated with increased risk of aortic dilation and related complications; however, current risk assessment is not effective. Most of BAV have three leaflets with a fusion between two of them of variable length. This study aimed to ascertain whether the extent of leaflet fusion (often called raphe) is related to aortic dilation and flow abnormalities in BAV with no significant valvular dysfunction. One hundred and twenty BAV patients with no significant valvular dysfunction or history of surgical repair or aortic valve replacement were consecutively and prospectively enrolled (September 2014-October 2018). Cardiac magnetic resonance protocol included a 4D flow sequence for haemodynamic assessment. Moreover, a stack of double-oblique cine images of the aortic valve were used to quantify fusion length (in systole) and leaflet length (diastole). Inter- and intra-observer reproducibility was tested in 30 randomly selected patients. Aortic valve leaflet fusion was measurable in 112 of 120 (93%) cases with good reproducibility (ICC = 0.826). Fusion length varied greatly (range: 2.3-15.4mm; mean: 7.8 ± 3.2mm). After correction for demographic and clinical conditions, fusion length was independently associated with diameter and z-score at the sinus of Valsalva (p = 0.002 and p = 0.002, respectively) and ascending aorta (p = 0.028 and p = 0.046). Fusion length was positively related to flow asymmetry, vortices and circumferential wall shear stress, thereby possibly providing a pathophysiological link with aortic dilation. Aortic valve fusion length is related to aortic dilation and flow abnormalities in BAV patients. • The length of the fusion between leaflets in non-dysfunctional bicuspid aortic valves varies substantially and can be reliably measured by cine CMR. • Aortic valve leaflet fusion length is independently related to aortic sinus and ascending aorta diameter. • Increased flow asymmetry, circumferential wall shear stress and presence of vortices are positively related to aortic valve leaflet fusion length.

Cataloging Of Unit Replacement Based On Long Run Repair Average Cost Rate (Acr) Based On Weibull Distribution Model

Large amounts of money are lost each year in the real-estate industry because of poor schedule and cost control, In Industry the investigated failure and repair pattern, reliabilities of generators, compressors, turbines, using simple statistical tools and simulation techniques. The repair duration is divided into the 1)Major repair 2)Minor repair ,In major repair having(repair hour greater than a threshold valve)and Minor repair having(repair hour less than (or)equal to threshold valve).This approach is mainly for Weibull distribution method. In Weibull analysis is a common method for failure analysis and reliability engineering used in a wide range of applications. In this paper, the applicability of Weibull analysis for evaluating and comparing the reliability of the schedule performance of multiple projects is presented, while the successive performance of multiple projects is presented ,while the successive repair times are increasing and are exposing to Weibull distribution ,under these assumptions ,an optimal replacement policy ‘T’ in which we replace the system ,when the repair time reaches T. It can be determined that an optimal repair replacement policy T* such that long run average cost and the corresponding optimal replacement policy T* can be determined analytically.

Trans-aortic Mitral Valve Repair and Aortic Valve Replacement with Rapid Deployment Prostheses in High Risk Patients

Objective: To report a case of trans-aortic mitral valve repair and aortic valve replacement with rapid deployment prosthesis in a high risk patient. Methods: A 79 year-old female underwent trans-aortic mitral valve repair and aortic valve replacement with rapid deployment prosthesis. Her past medical history revealed hypertension, COPD and diabetes. She was referred to our center for the worsening of dyspnea on exertion. Trans-thoracic echocardiogram showed a severe aortic regurgitation and moderate mitral regurgitation. The mechanism of mitral insufficiency was the chordal rupture of the scallop A2 while aortic valve was calcified. Ejection fraction was 45%. She was a very fragile patient with a intermediate surgical risk profile (Euroscore II: 6.6%). Results: After removing the calcified aortic valve, we carried out a trans-aortic mitral valve repair by cutting the two ruptured chords on A2 and performing an edge-to-edge plasty between A2 and P2. Afterwards, we implanted a rapid deployment aortic prosthesis. This approach allowed us to reduce the CPB and aortic cross clamp times. Post-operative TTE showed trivial mitral regurgitation and no aortic paravalvular leaks. The patient was in-hospital discharged by a week. Conclusions: In high risk patients suffering from mitro-aortic disease our approach could be safe and easy.

Discussion on construction scheme of aqueduct structure repair and water stop belt replacement in South-to-North Water Diversion project

Taking Shahe and Dalang River aqueducts as an example, this paper introduces a movable and reusable waterproof device for aqueduct construction, which is suitable for construction scheme of structure repair and waterstop belt replacement for large-scale water delivery aqueduct of Shahe River and Dalang River in South-to-North Water Diversion Project. It aims to solve structural damage and waterstop belt leakage of the aqueducts of Shahe River and Dalang River in the South-to-North Water Diversion Project, realizing the aqueduct construction with uninterrupted water supply, and structure repair and waterstop belt replacement in the waterless environment separated by watertight device in the aqueduct construction.

Resolution of post-anaesthesia aortic regurgitation by repair of a ruptured sinus of Valsalva aneurysm: 5 case reports

BackgroundRuptured sinus of Valsalva aneurysm (SVA) is a rare cardiovascular disease in which some patients exhibit aortic valve insufficiency. SVA repair and valve replacement are usually required for treatment. Here, we report 5 cases of ruptured SVA with severe post-anaesthesia aortic regurgitation (AR). To the best of our knowledge, this is the first report of ruptured SVA with severe post-anaesthesia AR.Case presentation:From 2018 to 2020, there were 5 cases of ruptured SVA with severe AR after anaesthesia in our hospital. The main symptoms were palpitation and shortness of breath. Transthoracic echocardiography (TTE) with colour-flow Doppler showed ruptured aortic sinus aneurysms without AR. Post-anaesthesia echocardiography showed severe AR. Direct patch closure of the ruptured aneurysm resolved the left-to-right shunt and AR, and the aortic valve was not replaced.ConclusionsPost-anaesthesia AR without obvious structural defects may occur in patients with ruptured SVAs. Valve replacement may not be necessary.

Finite Element Analysis of a Novel Aortic Valve Stent.

Worldwide, one of the leading causes of death for patients with cardiovascular disease is aortic valve failure or insufficiency as a result of calcification and cardiovascular disease. The surgical treatment consists of repair or total replacement of the aortic valve. Artificial aortic valve implantation via a percutaneous or endovascular procedure is the minimally invasive alternative to open chest surgery, and the only option for high-risk or older patients. Due to the complex anatomical location between the left ventricle and the aorta, there are still engineering design optimization challenges which influence the long-term durability of the valve. In this study we developed a computer model and performed a numerical analysis of an original self-expanding stent for transcatheter aortic valve in order to optimize its design and materials. The study demonstrates the current valve design could be a good alternative to the existing commercially available valve devices.

Analysis of Devices to Detect Longitudinal Tear on Conveyor Belts

Currently mining enterprises more and more often use belt conveyors for mining operations. The length of transporting rock mass could be several kilometers, so in most cases conveyor are used. The transported rock mass is rather heterogeneous, as a rule, it has inclusions in a form of large pieces with sharp edges and, in some cases, metal objects, which might cause longitudinal tears of various lengths on conveyor belts. They lead to significant repair costs or replacement of expensive conveyor belt, loss of transported material, and downtime of the major enterprise equipment. In the world practice various devices and systems to detect longitudinal tears on conveyor belts have been developed for their successful operation. In this paper, there is analysis of existing devices to detect longitudinal tears on conveyor belts based on the use of mechanical (detection of the transported cargo on the lower the conveyor section and measuring the belt width), ultrasonic and electro-magnetic energy, evaluation of changes in the magnetic field configuration, computer vision, infrared laser and x-ray radiation, image recognition software and embedded transponder chips.

P589Assessment of cardiac reverse remodelling following mitral valve repair and mitral valve replacement in degenerative mitral regurgitation: a cardiovascular magnetic resonance study

Abstract Background Mitral valve (MV) repair is currently recommended over replacement (1). The guidelines suggesting this are however based on historic evidence which compared outdated techniques of MV replacement. Recent data cast doubts on its validity in the current era of chordal-preservation techniques in MV replacement. Purpose Using cardiovascular magnetic resonance (CMR) imaging, this study aimed to assess the impact of MV repair and MV replacement on cardiac left ventricular (LV) reverse remodelling. Methods 65 patients with moderate-severe and severe mitral regurgitation (MR) were prospectively recruited. Of these, 37 patients (59% men, 65±15 years) to date with paired CMR scans at baseline and at 6 months were evaluated. Patients either underwent MV repair (n=9), MV replacement (n=10) or watchful waiting (n=18). The CMR protocol included cines for left ventricle (LV), left atria (LA), and aortic flow assessment. The LA and LV parameters, and MR fraction were analysed. Results At 6 months, both the MV repair and replacement groups exhibited a reduction in LV end-diastolic volume (LVEDV) and LA volumes when compared to the control group. The indexed LVEDV decreased significantly from 129±33ml/m2 to 99±37ml/m2, p&lt;0.001 in the repair group, from 118±24ml/m2 to 90±26ml/m2, p&lt;0.001 in the replacement group and remained unchanged in the control group 115±25ml/m2 to 113±25ml/m2, p=0.53. The absolute reduction in indexed LVEDV was not significantly different between the repair and replacement groups (−30±15ml/m2 vs −29±19ml/m2, repair vs replacement, p=1.00). Similarly, both surgical groups also sustained an equal degree of LA size reduction (−42±26ml/m2 vs −36±23ml/m2, repair vs replacement; p=1.00). There was a decline in the global postoperative LV ejection fraction (Table 1). The degree of reduction in LV ejection fraction however did not differ between the repair and replacement group (−9±6% vs −6±8%, repair vs replacement; p=1.00). Those undergoing surgery experienced a significant reduction in their MR severity, although those with replacement had a more effective reduction in MR severity (MR fraction for repair: 47±9% to 15±10%, p&lt;0.001 vs replacement: 41±13% to 5±4%, p&lt;0.001). Conclusion MV surgery leads to atrial and left ventricular reverse remodelling, and a decline in global LV ejection fraction. In this small series, MV replacement with chordal preservation showed similar cardiac reverse remodelling benefits to MV repair. Although residual MR is often seen following repair, this did not lead to less favourable cardiac reverse remodelling. Acknowledgement/Funding Leeds NIHR infrastructure

Minimal repair of failed components in coherent systems

The minimal repair replacement is a reasonable assumption in many practical systems. Under this assumption a failed component is replaced by another one whose reliability is the same as that of the component just before the failure, i.e., a used component with the same age. In this paper we study the minimal repair in coherent systems. We consider both the cases of independent and dependent components. Three replacement policies are studied. In the first one, the first failed component in the system is minimally repaired while, in the second one, we repair the component which causes the system failure. A new technique based on the relevation transform is used to compute the reliability of the systems obtained under these replacement policies. In the third case, we consider the replacement policy which assigns the minimal repair to a fixed component in the system. We compare these three options under different stochastic criteria and for different system structures. In particular, we provide the optimal strategies for all the coherent systems with 1–4 independent and identically distributed components.

A Case of Type I Debranching Complicated by Anastomotic Pseudoaneurysm: Do Not Ask Too Much of the Ascending Aorta.

Treatment of aortic arch aneurysm with standard open surgery is technically demanding, and associated morbidity and mortality are not insignificant. In high-risk patients, hybrid procedures with debranching and reimplantation or bypass of the aortic arch vessel followed by thoracic endovascular aortic repair (TEVAR) in the aortic arch represent a valid alternative to open surgery. However, when the ascending aorta is mildly dilated, the risk of retrograde dissection increases sharply. Here, we report a case of thoracic aortic aneurysm, with normal ascending aorta diameter, treated with Type I debranching and anterograde TEVAR complicated by anastomotic pseudoaneurysm and acute endocarditis, treated ultimately with ascending aortic repair and aortic valve replacement.

Development of a visible light, cross-linked GelMA hydrogel containing decellularized human amniotic particles as a soft tissue replacement for oral mucosa repair.

Early effective treatment of oral mucosal defects is the key to ensuring defect healing and functional recovery. The application of human amniotic membrane (HAM) in promoting wound healing has been shown to be safe and effective. However, amniotic membrane is thin, easy to tear and difficult to handle. Combined with the natural forces at play in the oral cavity, this has restricted the clinical applications of HAM for healing of mucosal defects. Methacrylated gelatin (GelMA) has good mechanical strength and adhesion, and can be used as a bionic repair film to attach to the damaged surface of oral mucosa, but GelMA lacks bioactive substances and cannot promote the rapid repair of oral mucosal defects. The aim of this study was to design a type of composite GelMA hydrogel mixed with decellularized human amniotic particles (dHAP) as an oral mucosa substitute, to promote regeneration of defective mucosa by stimulating rapid angiogenesis. The composite substitute GelMA–dHAP was easy to synthesize and store, and easy to operate for repair of oral mucosal defects. We show the angiogenic potential of GelMA–dHAP on chick chorioallontoic membrane and the curative effect of GelMA–dHAP as a treatment in the rabbit oral mucosa defect model. In conclusion, this study confirms the effectiveness of GelMA–dHAP as an ideal soft tissue substitute for the repair of oral mucosal defects, overcoming the shortcomings of using HAM or GelMA alone.