Transcatheter pulmonic valve implantation: Techniques, current roles, and future implications

Right ventricular outflow tract(RVOT)obstruction is present in a variety of congenital heart disease states including tetralogy of Fallot,pulmonary atresia/stenosis and other conotruncal abnormalities etc.After surgical repair,these patients develop RVOT residual abnormalities of pulmonic stenosis and/or insufficiency of their native outflow tract or right ventricle to pulmonary artery conduit.There are also sequelae of other surgeries like the Ross operation for aortic valve disease that lead to right ventricle to pulmonary artery conduit dysfunction.Surgical pulmonic valve replacement(SPVR)has been the mainstay for these patients and is considered standard of care.Transcatheter pulmonic valve implantation(TPVI)was first reported in 2000 and has made strides as a comparable alternative to SPVR,being approved in the United States in 2010.We provide a comprehensive review in this space–indications for TPVI,detailed procedural facets and up-to-date review of the literature regarding outcomes of TPVI.TPVI has been shown to have favorable medium-term outcomes free of reinterventions especially after the adoption of the practice of pre-stenting the RVOT.Procedural mortality and complications are uncommon.With more experience,recognition of risk of dreaded outcomes like coronary compression has improved.Also,conduit rupture is increasingly being managed with transcatheter tools.Questions over endocarditis risk still prevail in the TPVI population.Head-to-head comparisons to SPVR are still limited but available data suggests equivalence.We also discuss newer valve technologies that have limited data currently and may have more applicability for treatment of native dysfunctional RVOT substrates.

In vitro bench testing using patient-specific 3D models for percutaneous pulmonary valve implantation with Venus P-valve

Background:Due to the wide variety of morphology,size,and dynamics,selecting an optimal valve size and location poses great difficulty in percutaneous pulmonary valve implantation(PPVI).This study aimed to report our experience with in vitro bench testing using patient-specific three-dimensional(3D)-printed models for planning PPVI with the Venus P-valve.Methods:Patient-specific 3D soft models were generated using PolyJet printing with a compliant synthetic material in 15 patients scheduled to undergo PPVI between July 2018 and July 2020 in Central China Fuwai Hospital of Zhengzhou University.Results:3D model bench testing altered treatment strategy in all patients(100%).One patient was referred for surgery because testing revealed that even the largest Venus P-valve would not anchor properly.In the remaining 14 patients,valve size and/or implantation location was altered to avoid valve migration and/or compression coronary artery.In four patients,it was decided to change the point anchoring because of inverted cone-shaped right ventricular outflow tract(RVOT)(n=2)or risk of compression coronary artery(n=2).Concerning sizing,we found that an oversize of 2-5 mm suffices.Anchoring of the valve was dictated by the flaring of the in-and outflow portion in the pulmonary artery.PPVI was successful in all 14 patients(absence of valve migration,no coronary compression,and none-to-mild residual pulmonary regurgitation[PR]).The diameter of the Venus P-valve in the 3D simulation group was significantly smaller than that of the conventional planning group(36[2]vs.32[4],Z=-3.77,P<0.001).Conclusions:In vitro testing indicated no need to oversize the Venus P-valve to the degree recommended by the balloon-sizing technique,as 2-5 mm sufficed.

Mechanism and Correlated Factors of SAM Phenomenon after Aortic Valve Replacement

To investigate the mechanism and correlated factors of systolic anterior motion （SAM） phenomenon after aortic valve replacement, 48 patients with severe aortic valvular stenosis were studied. Tested by echo-Doppler one week after aortic valve replacement, the patients were divided into two groups： SAM group and non-SAM group. The data of the left ventricular end-diastolic diameters, the left ventricular end-systolic diameters, the left ventricular outflow diameters, the thickness of the interventricular septum, the posterior wall of left ventricle, the blood velocities of left ventricular outflow and intra-cavitary gradients were recorded and compared. The results showed that no patients died during or after the operation. The blood velocities of left ventricular outflow was increased significantly in 9 patients （〉2.5 m/s）, and 6 of them developed SAM phenomenon. There was significant difference in all indexes （P〈0.05 or P〈0.01） except the posterior wall of left ventricle （P〉0.05） between two groups. These indicated that the present of SAM phenomenon after aortic valve replacement may be directly related to the increase of blood velocities of left ventricular outflow and intra-cavitary gradients. It is also suggested that smaller left ventricular diastolic diameters, left ventricular systolic diameters, left ventricular outflow diameters and hypertrophy of interventricular septum may be the anatomy basis of SAM phenomenon.

The effects of severe aortic stenosis and high pulmonary artery pressure on aortic valve replacement

Background: Pulmonary hypertension development in pure severe aortic stenosis is a situation that affects mortality and morbidity. Material and Methods: Data from files of 31 patients with systolic pulmonary artery pressure over 50 mm Hg and with pure severe aortic stenosis, and underwent aortic valve replacement in our clinic were examined retrospectively. Results: Preoperative effort capacities of the patients were evaluated as follows according to NYHA;4 patients class 1-2, 16 patients class 3, and 11 patients class 4. Twenty-five metal, and 6 biologic aortic valves were used. Postoperative hospital mortality was recorded as 12% with 4 patients. Patients were reevaluated on the postoperative 2nd and 12th months. Pulmonary arterial pressure of the patients was measured using echocardiography. Preoperative average pulmonary artery systolic pressure was measured as 55 ± 3 mmHg. The average pressure was measured as 41 ± 3 mmHg on the 2nd, and as 37.8 ± 4 mmHg on the 12th month. The effort capacity evaluation in the postoperative 2nd month was as follows: 11 patients class 1-2, 12 patients class 3, and 4 patients class 4. The effort capacity evaluation conducted in the 12th month was: 14 patients were class 1-2, 10 patients were class 3, and 2 patients were class 4. During the follow-up 1 year, survival rate of the patients was determined as 83.8% average, 5 year survival rate was determined as 61.5%. Conclusion: We believe that AVR may be performed in severe aortic stenosis cases with high pulmonary pressure with acceptable ortality, leading to a better quality and longer life.

A retrospective study of occlusal reconstruction in patients with old jaw fractures and dentition defects

Purpose:This study evaluated the methods and clinical effects of multidisciplinary collaborative treatment for occlusal reconstruction in patients with old jaw fractures and dentition defects.Methods:Patients with old jaw fractures and dentition defects who underwent occlusal reconstruction at the Third Affiliated Hospital of Air Force Military Medical University from January 2018 to December 2022 were enrolled.Clinical treatment was classified into 3 phases.In phase I,techniques such as orthognathic surgery,microsurgery,and distraction osteogenesis were employed to reconstruct the correct 3-dimensional(3D)jaw position relationship.In phase II,bone augmentation and soft tissue management techniques were utilized to address insufficient alveolar bone mass and poor gingival soft tissue conditions.In phase III,implant-supported overdentures or fixed dentures were used for occlusal reconstruction.A summary of treatment methods,clinical efficacy evaluation,comparative analysis of imageological examinations,and satisfaction questionnaire survey were utilized to evaluate the therapeutic efficacy in patients with traumatic old jaw fractures and dentition defects.All data are summarized using the arithmetic mean±standard deviation and compared using independent samplet-tests.Results:In 15 patients with old jaw fractures and dentition defects(an average age of 32 years,ranging from 18 to 53 years),there were 7 cases of malocclusion of single maxillary fracture,6 of malocclusion of single mandible fracture,and 2 of malocclusion of both maxillary and mandible fractures.There were 5 patients with single maxillary dentition defects,2 with single mandibular dentition defects,and 8 with both maxillary and mandibular dentition defects.To reconstruct the correct 3D jaw positional relationship,5 patients underwent Le Fort I osteotomy of the maxilla,3 underwent bilateral sagittal split ramus osteotomy of the mandible,4 underwent open reduction and internal fixation for old jaw fractures,3 underwent temporomandibular joint surgery,and 4 underwent distraction osteogenesis.All patients underwent jawbone augmentation,of whom 4 patients underwent a free composite vascularized bone flap(26.66%)and the remaining patients underwent local alveolar bone augmentation.Free gingival graft and connective tissue graft were the main methods for soft tissue augmentation(73.33%).The 15 patients received 81 implants,of whom 11 patients received implant-supported fixed dentures and 4 received implant-supported removable dentures.The survival rate of all implants was 93.82%.The final imageological examination of 15 patients confirmed that the malocclusion was corrected,and the clinical treatment ultimately achieved occlusal function reconstruction.The patient satisfaction questionnaire survey showed that they were satisfied with the efficacy,phonetics,aesthetics,and comfort after treatment.Conclusion:Occlusal reconstruction of old jaw fractures and dentition defects requires a phased sequential comprehensive treatment,consisting of 3D spatial jaw correction,alveolar bone augmentation and soft tissue augmentation,and implant-supported occlusal reconstruction,achieving satisfactory clinical therapeutic efficacy.

Role of precoating in artificial vessel endothelialization

As the progress of vascular surgery, artificial vessels have become the substitute for large and middle diameter vessels but have not for small diameter ones owing to thrombogenesis and occlusion within a short period of time after being applied. Artificial vessel endothelialization is one of the ideal methods to resolve such issue and has been improved continuously since Herring in 1978 put forward this term in the first time and utilized vascular endothelial cells (ECs) harvested from living animals to perform the test of artificial vessel endothelialization. However, human endothelial cells show little adhesion to the currently available vascular graft materials and some expanded polytetrafluoroethylene (ePTFE) grafts have shown only 10%+/-7% endothelial cell attachment rate (ECA, ie, attachment of ECs when incubated in vitro). Moreover, when the graft is exposed to pulsatile blood flow, a high proportion of cells are washed off from the lumen. Maximum cell loss occurs in the first 30-45 min after exposure to pulsatile flow, with up to 70% of cells lost. After that, a slower exponential loss occurs over the next 24 h. The lack of retention of cells could be partly overcome by sodding, but other techniques, involving engineering the lumen to improve ECA and endothelial cell retention rate (ECR, ie, retention of ECs when the grafts are exposed to pulsatile flow) have been developed. These include shear stress preconditioning, electrostatic charging and, above all, most successfully to date, precoating with EC specific adhesive glues that are mostly found in the extracellular basement membrane of blood vessels. The commonest are chemical coatings, preclotting, chemical bonding, and surface modifications.

Shoulder hemiarthroplasty for the treatment of complex proximal humeral fractures

Objective: To investigate the indication, perioperative announcements, selection of prosthesis and clinical results of shoulder hemiarthroplasty for the treatment of complex proximal humeral fractures.Methods: A total of 55 patients who suffered from com-plex proximal humeral fractures were treated by shoulder hemiarthroplasty. The mean age was 55.6 years and mean follow-up period was 25.1 months. The scoring system modi-fication for hemiarthroplasty (SSMH) had been adopted for evaluation at the latest follow-up.Results: The pain was obviously relieved in all patients. Fifty patients were painless and 5 patients had slight pain. The mean range of motion was 100°(90°-110°) in abduction, 95°(80°-100°) in forward flexion, 35°(30°-40°) in extemal rotation and internal rotation was confined at L2 level (L1-L3). The mean SSMH score was 27.9 (24-29). Fifty patients (90.1%) were satisfied with the clinical outcome.Conclusions: Shoulder hemiarthroplasty is an effective method to treat complex proximal humeral fractures. The proper selection of patients and prosthesis, good operation skill and enough functional exercise are the key points of successful treatment.

Malignant transformation of aneurysmal bone cysts： a case report

An aneurysmal bone cyst is a non-neoplastic, .destructive and expansile lesion consisting of a＂blood-filled sponge＂ that is defined to represent a benign reactive vascularity. Szendroi et al suggested that the aneurysmal bone cyst corresponds to a haemodynamic disturbance that is primary or secondary venous malformation of the bones. The association with trauma including fracture has also been noted and 25%-71% of such patients have a history of trauma. Conventionally, malignant transformation of aneurysmal bone cysts is perceived as a rare occurrence except those induced by irradiation. Both malignant fibrous histiocytoma and osteosarcoma have been reported in the malignant transformation cases.

Treatment of infrarenal abdominal aortic dissection concomitant with an aneurysm

Aortic dissection occurs when layers of the aortic ,walls are separated by the blood flow through an intimal tear. Dissection of the aorta most frequently originates in the ascending aorta （70%）, followed by the descending aorta （22%）, the aortic arch （7%） and the abdominal aorta （1/%）.1 The dissection limited to the abdominal aorta is rare.2 An isolated abdominal aortic dissection （IAAD） concomitant with an abdominal aortic aneurysm （AAA） is uncommon. We present here one patient with IAAD and AAA treated by endovascular therapy.

Surgical left atrial appendage occlusion in patients with atrial fibrillation undergoing mechanical heart valve replacement

Background:Surgical left atrial appendage occlusion(SLAAO)may be associated with a lower risk of thromboembolism in patientswith atrial fibrillation undergoing cardiac surgery.However,evidence regarding the effectiveness of SLAAO in patients undergoingmechanical heart valve replacement(MHVR)is lacking.Therefore,we aimed to evaluate the association between SLAAO and thecardiovascular outcomes in patients with atrial fibrillation undergoing MHVR.Methods:We retrospectively analyzed data for 497 patients with atrial fibrillation;27.6%of the patients underwent SLAAO,andthe remainder of the patients did not(No-SLAAO group).The primary outcome was a composite of ischemic stroke,systemicembolism,and all-cause mortality.Cumulative event-free survival rates were estimated using Kaplan-Meier curves,and weperformed multivariate Cox analyses to evaluate the association between SLAAO and outcomes.We used one-to-one propensityscore matching to balance patients’baseline characteristics,and analyzed 120 matching pairs.Results:Five patients died within 30 days postoperatively,and there were no significant differences between the two groupsregarding in-hospital complications(all P>0.05).After a median follow-up of 14 months,14 primary events occurred.Kaplan-Meier curves showed no difference in the cumulative incidence of freedom from the primary outcome(log-rank P=0.830),hemorrhagic events(log-rank P=0.870),and the secondary outcome(log-rank P=0.730),between the two groups.MultivariableCox proportional hazards regression analysis showed no association between SLAAO and any outcome(all P>0.05).Afterpropensity score matching,cardiopulmonary bypass time and aortic cross-clamp time,and the postoperative length of stay weresignificantly longer in the SLAAO group(all P<0.05);results were similar to the unadjusted analyses.Conclusions:Concomitant SLAAO and MHVR was associated with longer length of stay,and cardiopulmonary bypass time andaortic cross-clamp time,but was not associated with additional protective effects against thromboembolic events and mortalityduring the 14-month follow-up.