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Challenges and opportunities in improving left ventricular remodelling and clinical outcome following surgicaland trans-catheter aortic valve replacement

《医学前沿(英文)》 2021年 第15卷 第3期   页码 416-437 doi: 10.1007/s11684-021-0852-7

摘要: Over the last half century, surgical aortic valve replacement (SAVR) has evolved to offer a durable and efficient valve haemodynamically, with low procedural complications that allows favourable remodelling of left ventricular (LV) structure and function. The latter has become more challenging among elderly patients, particularly following trans-catheter aortic valve implantation (TAVI). Precise understanding of myocardial adaptation to pressure and volume overloading and its responses to valve surgery requires comprehensive assessments from aortic valve energy loss, valvular-vascular impedance to myocardial activation, force-velocity relationship, and myocardial strain. LV hypertrophy and myocardial fibrosis remains as the structural and morphological focus in this endeavour. Early intervention in asymptomatic aortic stenosis or regurgitation along with individualised management of hypertension and atrial fibrillation is likely to improve patient outcome. Physiological pacing via the His-Purkinje system for conduction abnormalities, further reduction in para-valvular aortic regurgitation along with therapy of angiotensin receptor blockade will improve patient outcome by facilitating hypertrophy regression, LV coordinate contraction, and global vascular function. TAVI leaflet thromboses require anticoagulation while impaired access to coronary ostia risks future TAVI-in-TAVI or coronary interventions. Until comparable long-term durability and the resolution of TAVI related complications become available, SAVR remains the first choice for lower risk younger patients.

关键词: surgical aortic valve replacement     trans-catheter aortic valve implantation     left ventricular hypertrophy and fibrosis     myocardial force-velocity relationship     His-Purkinje pacing     renin-angiotensin system inhibitors     coronary access impairment    

The evolution of surgical and medical treatment of aortic root aneurysm

null

《医学前沿(英文)》 2014年 第8卷 第4期   页码 427-432 doi: 10.1007/s11684-014-0385-4

摘要:

Since first report of aortic root replacement in 1968, the surgical risk and long term outcome of patients with aortic root aneurysm have been continuously improving. In the last 30 years, the surgical approach is also evolving towards more valve conservation with prophylactical intervention at an earlier clinical stage. Translational research has also led to emerging surgical innovation and new drug therapy. Their efficacies are currently under vigorous clinical trials and evaluations.

关键词: aortic root aneurysm     aortic root replacement     valve sparing root replacement     personalised external aortic root support    

Right coronary occlusion following transcatheter aortic valve implantation: two case reports

null

《医学前沿(英文)》 2016年 第10卷 第3期   页码 351-355 doi: 10.1007/s11684-016-0465-8

摘要:

This paper discusses two male patients with severe aortic stenosis, whose right coronary arteries (RCA) were completely occluded during transcatheter aortic valve implantation (TAVI), leading to fatal hemodynamic disorder. Occlusions of RCA complicated by TAVI are rare. In addition, emergency cardiopulmonary bypass (CPB) played a critical role in rescuing our second patient. Both patients were admitted for “severe aortic stenosis,” and TAVIs were performed. The first patient’s blood pressure immediately dropped to 70/40 mmHg after the balloon expansion and did not increase much after the administration of aramine or fluid therapy. He did not receive emergency surgery and died after 1.5 h of resuscitation. The second patient’s blood pressure fluctuated greatly for several minutes after the valve implantation, ranging from 170/100 mmHg to 60/40 mmHg. Angiography revealed a total occlusion of RCA. Thoracic surgery with CPB was performed, and the patient survived.

关键词: aortic stenosis     transcatheter aortic valve implantation     right coronary occlusion     cardiac group    

Histopathological study of congenital aortic valve malformations in 32 children

HUANG Ping, WANG Hongwei, LI Yanping, CHENG Peixuan, LIU Qingjun, ZHANG Zhenlu, LIU Jianying

《医学前沿(英文)》 2007年 第1卷 第1期   页码 74-78 doi: 10.1007/s11684-007-0015-5

摘要: The histopathological characteristics of congenital aortic valve malformations in children were investigated. All the native surgically excised aortic valves from 32 pediatric patients suffering from symptomatic aortic valve dysfunction due to congenital aortic valve malformations between January 2003 and December 2005 were studied macroscopically and microscopically. The patients medical records were reviewed and the clinical information was extracted. The diagnosis was made by the clinical presentation, preoperative echocardiography, intraoperative examination, and postoperative histopathological study, excluding rheumatic or degenerative aortic valve diseases, infective endocarditis and primary connective tissue disorders, e.g. Marfan syndrome. Among 32 children with congenital aortic valve malformations, the age was ranged from six to 18 years, with a mean of 14.9 years, and there were 27 boys and five girls (male: female = 5.4:1). There were five cases of aortic stenosis (AS, 15.62%), 25 cases of aortic insufficiency (AI, 78.13%) and two cases of AS-AI (6.25%), without other valve diseases. Twenty cases still had other congenital heart diseases: ventricular septal defect (19 cases), patent ductus arteriosus (two cases), double-chambered right ventricle (one case), aneurysm of the right anterior aortic sinus of valsalva (three cases). Histopathological examination indicated that the cusps became thickening with unequal size, irregular shape (coiling and prolapse edge), enhanced hardness, and partly calcification. Microscopic investigation revealed the unsharp structure of valve tissue, fibrosis, myxomatous, reduced collagen fiber, rupture of elastic fibers, different degrees of infiltration of inflammatory cells, secondary calcareous and lipid deposit, and secondary fibrosis. Congenital aortic valve malformations in children involve males more than females, mostly associated with other congenital heart diseases. Aortic insufficiency is more common in children with congenital aortic valve malformations. Histopathologically, the leaflets of aortic valve are mainly myxomatous, thickening with unequal size, irregular shape (coiling and prolapse edge), reduced collagen fiber, rupture of elastic fibers, without small vessel proliferation and inflammatory cell infiltration, fibrosis and calcification rarely seen.

Evaluation of the harmonic scalpel in open surgery for abdominal aortic aneurysm

null

《医学前沿(英文)》 2012年 第6卷 第1期   页码 85-88 doi: 10.1007/s11684-012-0174-x

摘要:

The harmonic scalpel is a hemostatic device primarily designed for use in laparoscopic surgery. During the last few years, many surgeons have begun to use the harmonic scalpel in open surgery. Several papers have cited the benefits of the device compared with conventional knot-tying techniques; however, no evidence showing the advantages of using the harmonic scalpel in complicated abdominal aortic aneurysm (AAA) surgery has been presented. The aim of the present study is to determine the value of the harmonic scalpel in open operation for AAA. A total of 153 patients who underwent open surgery for AAA at the Department of Vascular Surgery of Guangdong General Hospital, China between January 2001 and December 2010, were retrospectively analyzed. Open surgery performed with the harmonic scalpel on 105 patients was compared with open operation using conventional knot-tying techniques on 48 patients. The operative time, intraoperative blood loss, total postoperative drainage fluid volumes, hospital stay, and postoperative complications between the two groups were compared. The harmonic scalpel group was associated with a shorter operation time (113.2±23.6 min vs. 232.1±39.2 min, P<0.01) and lower intraoperative blood loss (126.1±96.6 ml vs. 592.1±207.2 ml, P<0.01). Postoperative drainage fluid volumes were greater in the conventional surgery group than in the harmonic scalpel group (702.1±192.8 ml vs. 198.5±97.4 ml, P<0.01). The hospital stay was shorter for the harmonic scalpel group than for the conventional surgery group (10.7±3.3 d vs. 16.5±4.7 d, P<0.05). No differences between the postoperative complications or hospital mortality of the two groups were found. The harmonic scalpel is a safe and minimally invasive tool in open surgery for AAA and is associated with shorter operative time, shorter hospital stay, and lower intraoperative blood loss and postoperative drainage fluid volumes compared with conventional knot-tying techniques.

关键词: abdominal aortic aneurysm     harmonic scalpel     minimally invasive    

Development of a novel hand−eye calibration for intuitive control of minimally invasive surgical robot

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0698-y

摘要: Robotic-assisted surgical system has introduced a powerful platform through dexterous instrument and hand−eye coordination intuitive control. The knowledge of laparoscopic vision is a crucial piece of information for robot-assisted minimally invasive surgery focusing on improved surgical outcomes. Obtaining the transformation with respect to the laparoscope and robot slave arm frames using hand−eye calibration is essential, which is a key component for developing intuitive control algorithm. We proposed a novel two-step modified dual quaternion for hand−eye calibration in this study. The dual quaternion was exploited to solve the hand−eye calibration simultaneously and powered by an iteratively separate solution. The obtained hand−eye calibration result was applied to the intuitive control by using the hand−eye coordination criterion. Promising simulations and experimental studies were conducted to evaluate the proposed method on our surgical robot system. We extensively compared the proposed method with state-of-the-art methods. Results demonstrate this method can improve the calibration accuracy. The effectiveness of the intuitive control algorithm was quantitatively evaluated, and an improved hand−eye calibration method was developed. The relationship between laparoscope and robot kinematics can be established for intuitive control.

关键词: minimally invasive surgery     hand−eye calibration     intuitive control     surgical robot     dual quaternion    

engineering in the construction of numerical simulation oriented patient-specific model of stented aortic

Xianlong MENG, Wenyu FU, Yun ZHANG, Aike QIAO,

《机械工程前沿(英文)》 2010年 第5卷 第3期   页码 328-335 doi: 10.1007/s11465-010-0026-9

摘要: Patient-specific models are widely used in hemodynamic simulations. The flow in the boundary layer changes so strongly that fine meshes in the boundary layer are required in numerical simulations, especially for the calculation of wall shear stress and its gradient. To precisely analyze hemodynamics, it is necessary to investigate the approaches to the reconstruction of a numerical simulation-oriented patient-specific model for aortic arch aneurysm that can perform particular meshing in the boundary layer. Based on a surface model of aortic arch aneurysm in STL format, reverse engineering concept was applied to reconstruct a solid model using CAD software Geomagic and Pro/E, and a simplified model of stent for the intervention of aortic arch aneurysm was also created. After these models were imported to ANSYS, a block modeling approach was employed to divide the whole model into several domain blocks to adopt different meshing strategies. Particular meshing was performed especially in the boundary layer and around the stents. The finite element model particularly suitable for numerical simulation of hemodynamics was obtained. Hemodynamic simulation was performed, using the constructed finite element model to verify its applicability. The results indicate that reverse engineering concept and the proposed block modeling approach can be used to divide the solid model of aortic arch aneurysm into multiple volumes, which can be meshed according to particular requirements in each volume; the finite element model of stented aortic arch aneurysm can be employed to simulate hemodynamics. The approaches of modeling were applicable not only for aortic arch aneurysm, but also for similar model reconstruction as a reference in hemodynamic simulation investigations.

关键词: reverse engineering     aortic arch aneurysm     surface model     meshing     finite element model    

Identification of variants associated with sporadic thoracic aortic dissection: a case--control study

《医学前沿(英文)》 2021年 第15卷 第3期   页码 438-447 doi: 10.1007/s11684-020-0826-1

摘要: Thoracic aortic dissection (TAD) without familial clustering or syndromic features is known as sporadic TAD (STAD). So far, the genetic basis of STAD remains unknown. Whole exome sequencing was performed in 223 STAD patients and 414 healthy controls from the Chinese Han population (N = 637). After population structure and genetic relationship and ancestry analyses, we used the optimal sequence kernel association test to identify the candidate genes or variants of STAD. We found that COL3A1 was significantly relevant to STAD (P = 7.35 × 10−6) after 10 000 times permutation test (P = 2.49 × 10−3). Moreover, another independent cohort, including 423 cases and 734 non-STAD subjects (N = 1157), replicated our results (P = 0.021). Further bioinformatics analysis showed that COL3A1 was highly expressed in dissected aortic tissues, and its expression was related to the extracellular matrix (ECM) pathway. Our study identified a profile of known heritable TAD genes in the Chinese STAD population and found that COL3A1 could increase the risk of STAD through the ECM pathway. We wanted to expand the knowledge of the genetic basis and pathology of STAD, which may further help in providing better genetic counseling to the patients.

关键词: sporadic thoracic aortic dissection     exome sequencing     gene COL3A1     case–control study     extracellular matrix    

Aneurysmal dilatation of the aortic sinuses of Valsalva — beyond Marfan syndrome: a single centre experience

null

《医学前沿(英文)》 2014年 第8卷 第4期   页码 419-426 doi: 10.1007/s11684-014-0383-6

摘要:

Aneurysmal dilatation of the aortic sinuses of Valsalva has been most extensively documented in the setting of aortopathies, particularly Marfan syndrome. On the other hand, there is limited data in the literature about congenital sinus of Valsalva aneurysms outside this context. For the purpose of this review, we carried out a literature search on aneurysmal dilatation of the sinuses of Valsalva in Marfan syndrome, and compared this with congenital sinus of Valsalva aneurysms, also including data from a case series from our institution. In conclusion, there are differences in management of aortic dilatation in Marfan syndrome and congenital sinus of Valsalva aneurysms. Though less well-recognised, congenital aneurysms are often associated with significant morbidity and mortality and timely intervention is necessary.

关键词: sinus of Valsalva aneurysms     Marfan syndrome     aortic dissection    

Clinical significance of para-aortic lymph node dissection and prognosis in ovarian cancer

null

《医学前沿(英文)》 2014年 第8卷 第1期   页码 96-100 doi: 10.1007/s11684-014-0316-4

摘要:

Lymph node metastasis has an important effect on prognosis of patients with ovarian cancer. Moreover, the impact of para-aortic lymph node (PAN) removal on patient prognosis is still unclear. In this study, 80 patients were divided into groups A and B. Group A consisted of 30 patients who underwent PAN+ pelvic lymph node (PLN) dissection, whereas group B consisted of 50 patients who only underwent PLN dissection. Analysis of the correlation between PAN clearance and prognosis in epithelial ovarian cancer was conducted. Nineteen cases of lymph node metastasis were found in group A, among whom seven cases were positive for PAN, three cases for PLN, and nine cases for both PAN and PLN. In group B, 13 cases were positive for lymph node metastasis. Our study suggested that the metastatic rate of lymph node is 40.0%. Lymph node metastasis was significantly correlated with FIGO stage, tumor differentiation, and histological type both in groups A and B (P<0.05). In groups A and B, the three-year survival rates were 77.9% and 69.0%, and the five-year survival rates were 46.7% and 39.2%, respectively. However, the difference was not statistically significant (P>0.05). The three-year survival rates of PLN metastasis in groups A and B were 68.5% and 41.4%, and the five-year survival rates were 49.7% and 26.4%, respectively. Furthermore, PLN-positive patients who cleared PAN had significantly higher survival rate (P=0.044). In group A, the three-year survival rates of positive and negative lymph nodes were 43.5% and 72.7%, and the five-year survival rates were 27.2% and 58.5%, respectively. The difference was statistically significant (P=0.048). Cox model analysis of single factor suggested that lymph node status affected the survival rate (P<0.01), which was the death risk factor. Consequently, in ovarian carcinoma cytoreductive surgery, resection of the para-aortic lymph node, which has an important function in clinical treatment and prognosis of patients with ovarian cancer, is necessary.

关键词: ovarian cancer     para-aortic lymph node     pelvic lymph node    

Cutting performance of surgical electrodes by constructing bionic microstriped structures

《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0728-9

摘要: Surgical electrodes rely on thermal effect of high-frequency current and are a widely used medical tool for cutting and coagulating biological tissue. However, tissue adhesion on the electrode surface and thermal injury to adjacent tissue are serious problems in surgery that can affect cutting performance. A bionic microstriped structure mimicking a banana leaf was constructed on the electrode via nanosecond laser surface texturing, followed by silanization treatment, to enhance lyophobicity. The effect of initial, simple grid-textured, and bionic electrodes with different wettabilities on tissue adhesion and thermal injury were investigated using horizontal and vertical cutting modes. Results showed that the bionic electrode with high lyophobicity can effectively reduce tissue adhesion mass and thermal injury depth/area compared with the initial electrode. The formation mechanism of adhered tissue was discussed in terms of morphological features, and the potential mechanism for antiadhesion and heat dissipation of the bionic electrode was revealed. Furthermore, we evaluated the influence of groove depth on tissue adhesion and thermal injury and then verified the antiadhesion stability of the bionic electrode. This study demonstrates a promising approach for improving the cutting performance of surgical electrodes.

关键词: surgical electrodes     tissue adhesion     thermal injury     bionic structures     cutting performance     medical tools    

Comparison of surgical indications for hysterectomy by age and approach in 4653 Chinese women

null

《医学前沿(英文)》 2014年 第8卷 第4期   页码 464-470 doi: 10.1007/s11684-014-0338-y

摘要:

Approximately one million hysterectomies are performed each year in China. However, national data regarding the indications and the surgical approaches for hysterectomy are lacking. The aim of this study was to examine the surgical indications for hysterectomy in different age groups and the relative merits of different surgical approaches for hysterectomy in Chinese women. Clinical data from 4653 cases of hysterectomy performed in Tongji Hospital from 2004 to 2009 were analysed. Hysterectomy was most commonly performed among women aged 40--49 years (2299; 49.4%). Overall, colporrhagia and abdominal pain were the two most common indications for hysterectomy. The most common indications by age groups were as follows: malignant ovarian tumour,<20 years; malignant uterine tumour, 20--29 and 30--39 years; uterine myoma, 40--49 and 50--59 years; and uterine prolapse, 60--69 and>70 years. The proportion of malignant aetiology also varied by age, being the highest in women aged<20 years (75.0%) and the lowest in those aged 40--49 years (19.9%). Approximately 35% women who had hysterectomies also had concomitant bilateral oophorectomy. The lowest rate of oophorectomy occurred in women aged 30--39 years (15.8%), whereas the highest rate was in those aged 50--59 years (75.9%). The abdominal surgical approach was used in 84% of all hysterectomies. Surgeries using the vaginal approach required a significantly shorter operating time (118 min average) than all other approaches (P<0.05). Both the amount of bleeding and the blood transfusion volume required were smaller in vaginal approaches, with no significant differences between the others. The surgical approaches used were also related to the scope of surgery. Both the surgical indications and the rates of bilateral oophorectomy varied by age. In terms of both operating time and the amount of bleeding and blood transfusion volume required, the vaginal approach was superior to all other surgical approaches.

关键词: hysterectomy     surgical indications     surgical approach     bilateral oophorectomy    

Potential indicators predict progress after surgical resection of gastrointestinal stromal tumors

null

《医学前沿(英文)》 2012年 第6卷 第3期   页码 317-321 doi: 10.1007/s11684-012-0203-9

摘要:

In order to find out the potential indicators predicting prognosis of malignant gastrointestinal stromal tumors (GISTs) after surgical resection, we collected clinical records of 80 patients with malignant GISTs. Tumor location, size, mitotic index, necrosis were compared with the prognosis of malignant GISTs by Kaplan-Meier method and log-rank test. After a median follow-up of 844 days (52–2 145), we found that as National Institutes of Health suggested, tumors with intermediate risk had more favorable prognosis than that with high risk. Their 3-year survival rate were 65.3% and 41.3%, respectively (P<0.001). Moreover, tumor size and mitotic index were associated with free survival. The 3-year survival rate for patients with tumor size≤10 cm and>10 cm were 62.3% and 41.8%, respectively (P = 0.002), Tumors with mitotic index≤5/50 HPF had a higher 3-year survival rate than tumors with mitotic index>5/50 HPF (67.1% versus 40.7%, P = 0.005). The presence of necrosis was directly related to the malignant behavior. The 3-year survival rate for presence and absence necrosis were 50.8% and 64.8% (P = 0.008). From the present study, we can conclude that besides tumors size and mitotic index, tumor location and necrosis also influence on the long-term survival of patient with malignant GISTs after surgical resection.

关键词: gastrointestinal stromal tumors     surgery     survival    

Novel piezoelectric pump with “E”-shaped valve found from sub-experiments

Jianhui ZHANG, Jun HUANG, Xiaoqi HU, Qixiao XI,

《机械工程前沿(英文)》 2010年 第5卷 第2期   页码 212-218 doi: 10.1007/s11465-010-0009-x

摘要: Increasing the driving frequency of a piezoelectric vibrator can resolve the bottleneck of low flow in a valve piezoelectric pump. However, a piezoelectric pump of a traditional valve body presents the hysteretic nature of the valve, and macroscopic performance is up-frequency to flow-sharply. This research is to settle the bottleneck mentioned above. First, through the sub-experiment on various parameters of the plate valve of a piezoelectric pump, the reasons why a valve body itself can influence “up-frequency to flow-sharply”, which causes the hysteretic nature of the valve, were discovered. Second, an “E”-shaped valve and piezoelectric pump with an “E”-shaped valve (PPEV) were invented. Finally, the efficiency of PPEV has been proved helpful to reduce hysteretic nature in experiments. Under the similar conditions, compared with traditional pumps, the driving frequency of novel PPEV can be more than 10 times high, and the flow rate also can be several times high.

关键词: piezoelectricity     valve     pump     experiment         E”     -shaped valve    

State-of-the-art of intelligent minimally invasive surgical robots

Masakatsu G. Fujie, Bo Zhang

《医学前沿(英文)》 2020年 第14卷 第4期   页码 404-416 doi: 10.1007/s11684-020-0743-3

摘要: A number of developed countries are rapidly turning into super-aged societies. Consequently, the demand for reduced surgical invasiveness and enhanced efficiency in the medical field has increased due to the need to reduce the physical burden on older patients and shorten their recovery period. Intelligent surgical robot systems offer high precision, high safety, and reduced invasiveness. This paper presents a review of current intelligent surgical robot systems. The history of robots and three types of intelligent surgical robots are discussed. The problems with current surgical robot systems are then analyzed. Several aspects that should be considered in designing new surgical systems are discussed in detail. The paper ends with a summary of the work and a discussion of future prospects for surgical robot development.

关键词: robot history     medical robot     surgical robot     radiofrequency ablation     organ model    

标题 作者 时间 类型 操作

Challenges and opportunities in improving left ventricular remodelling and clinical outcome following surgicaland trans-catheter aortic valve replacement

期刊论文

The evolution of surgical and medical treatment of aortic root aneurysm

null

期刊论文

Right coronary occlusion following transcatheter aortic valve implantation: two case reports

null

期刊论文

Histopathological study of congenital aortic valve malformations in 32 children

HUANG Ping, WANG Hongwei, LI Yanping, CHENG Peixuan, LIU Qingjun, ZHANG Zhenlu, LIU Jianying

期刊论文

Evaluation of the harmonic scalpel in open surgery for abdominal aortic aneurysm

null

期刊论文

Development of a novel hand−eye calibration for intuitive control of minimally invasive surgical robot

期刊论文

engineering in the construction of numerical simulation oriented patient-specific model of stented aortic

Xianlong MENG, Wenyu FU, Yun ZHANG, Aike QIAO,

期刊论文

Identification of variants associated with sporadic thoracic aortic dissection: a case--control study

期刊论文

Aneurysmal dilatation of the aortic sinuses of Valsalva — beyond Marfan syndrome: a single centre experience

null

期刊论文

Clinical significance of para-aortic lymph node dissection and prognosis in ovarian cancer

null

期刊论文

Cutting performance of surgical electrodes by constructing bionic microstriped structures

期刊论文

Comparison of surgical indications for hysterectomy by age and approach in 4653 Chinese women

null

期刊论文

Potential indicators predict progress after surgical resection of gastrointestinal stromal tumors

null

期刊论文

Novel piezoelectric pump with “E”-shaped valve found from sub-experiments

Jianhui ZHANG, Jun HUANG, Xiaoqi HU, Qixiao XI,

期刊论文

State-of-the-art of intelligent minimally invasive surgical robots

Masakatsu G. Fujie, Bo Zhang

期刊论文