1.Optimization of flow rate and orientation of outflow graft at implantation for patients with left ventricular assist device.
Yongyi WANG ; Li SHI ; Shijun HU ; Xiao TAN ; Tianli ZHAO
Journal of Central South University(Medical Sciences) 2025;50(3):457-468
OBJECTIVES:
A ventricular assist device (VAD) is an electromechanical device used to assist cardiac blood circulation, which can be employed for the treatment of end-stage heart failure and is most commonly placed in the left ventricle. Despite enhancing perfusion performance, the implantation of left ventricular assist device (LVAD) transforms the local intraventricular flow and thus may increase the risk of thrombogenesis. This study aims to investigate fluid-particle interactions and thromboembolic risk under different LVAD configurations using three-dimensional (3D) reconstruction models, focusing on the effects of outflow tract orientation and blood flow rates.
METHODS:
A patient-specific end-diastolic 3D reconstruction model was initially constructed in stereo lithography (STL) format using Mimics software based on CT images. Transient numerical simulations were performed to analyze fluid-particle interactions and thromboembolic risks for LVAD with varying outflow tract orientations under 2 flow rates (4 L/min and 5 L/min), using particles of uniform size (2 mm), and a blood flow rate optimization protocol was implemented for this patient.
RESULTS:
When the LVAD flow rate was 5 L/min, helicity and flow stagnation of the blood flow increased the particle residence time (RT) and the risk of thrombogenesis of the aortic root. The percentage of particles traveling toward the brachiocephalic trunk was up to 20.33%. When the LVAD flow rate was 4 L/min, blood turbulence in the aorta was reduced, the RT of blood particles was shortened, and then the percentage of particles traveling toward the brachiocephalic trunk decreased to 10.54%. When the LVAD blood flow rate was 5 L/min and the direction of the outflow pipe was optimal, the RT of blood particles was shortened, and then the percentage of particles traveling toward the brachiocephalic trunk decreased to 11.22%. A 18-month follow-up observation of the patient revealed that the LVAD was in good working order and the patient had no complications related to the implantation of LVAD.
CONCLUSIONS
Implantation of LVAD results in a higher risk of cerebral infarction; When implanting LVAD with the same outflow tract direction, optimizing flow velocity and outflow tract can reduce the risk of cerebral infarction occurrence.
Heart-Assist Devices/adverse effects*
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Humans
;
Heart Failure/physiopathology*
;
Blood Flow Velocity
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Thromboembolism/prevention & control*
;
Models, Cardiovascular
;
Heart Ventricles/physiopathology*
;
Imaging, Three-Dimensional
2.Midterm follow-up results of implantation of a fully biodegradable ventricular septal defect occluder
Xueyang GONG ; Yifeng YANG ; Tianli ZHAO ; Shijun HU ; Weizhi ZHANG
Journal of Central South University(Medical Sciences) 2024;49(5):795-801
Objective:Ventricular septal defect(VSD)is a prevalent congenital cardiac anomaly.By enhancing the occluder design and optimizing procedural approaches,the indications for VSD closure can be broadened while minimizing associated complications.The utilization of fully biodegradable occluder holds promising potential in resolving conduction block issues encountered during VSD closure.This study aims to compare the results of the fully biodegradable occluder with the metal occluder in transoesophageal echocardiography-guided VSD closure via lower sternal level minor incision at the interim follow-up,and to find risk factors for the occurrence of electrocardiographic and valvular abnormalities postoperatively. Methods:We reviewed the postoperative and 3-year follow-up data of all patients who underwent the randomized controlled study of VSD closure from January 1 to November 7,2019 in the Second Xiangya Hospital of Central South University.The safety and efficacy of the procedure were assessed and compared between the 2 groups by electrocardiogram and echocardiography results,and the risk factors for the occurrence of postoperative electrocardiogram and valve abnormalities were studied with Logistic regression analysis. Results:Twelve and fifteen patients underwent VSD closure with the metallic occluder and the fully biodegradable occluder,respectively.All patients survived during the follow-up period without major complications such as atrioventricular block,significant residual shunt,too rapid absorption of the occluder,and significant valvular regurgitation.There were no significant differences in the results of electrocardiograph and color Doppler ultrasonography the metal occluder group and the fully biodegradable occluder group 1,2,and 3 years after operation(all P>0.05).The size of the occluder were risk factors for tricuspid regurgitation at 2 and 3 years postoperatively,and the difference between the occluder size and the VSD defect size were risk factors for tricuspid regurgitation at 2 years postoperatively(P<0.05). Conclusion:This study adequately demonstrates the safety and efficacy of fully biodegradable occluders in small VSD closure and shows the same postoperative effects as conventional nitinol occluders.
3.Establishment and preliminary mechanism study of the zebrafish strain of KIAA0196: A candidate pathogenic gene for heart development.
Haisong BU ; Yifeng YANG ; Xiaoyu LUO ; Shijun HU ; Xueyang GONG ; Tianli ZHAO
Journal of Central South University(Medical Sciences) 2019;44(9):968-975
To explore the effects of KIAA0196 gene on cardiac development and the establishment of zebrafish strain.
Methods: Peripheral blood and gDNA from patients were extracted. Copy number variation analysis and target sequencing were conducted to screen candidate genes. The KIAA0196 knockout zebrafish was generated by CRISPR/Cas9 to detect whether KIAA0196 deficiency could affect cardiac development. Finally, the wild-type and mutant zebrafish were anatomized and histologically stained to observe the phenotype of heart defects.
Results: The KIAA0196 knockout zebrafish strain was successfully constructed using CRISPR/Cas9 technology. After 60 hours fertilization, microscopic examination of KIAA0196 knockout zebrafish (heterozygote + homozygote) showed pericardial effusion, cardiac compression and severely curly tail. Compared with wild-type zebrafish, the hearts of mutant KIAA0196 zebrafish had cardiac defects including smaller atrium and larger ventricle, and the myocardial cells were looser.
Conclusion: KIAA0196 gene plays an important regulatory role in the development of heart. It might be a candidate gene for congenital heart disease.
Animals
;
DNA Copy Number Variations
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Heart
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Heart Defects, Congenital
;
genetics
;
Humans
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Myocytes, Cardiac
;
Phenotype
;
Proteins
;
Zebrafish
;
genetics
;
Zebrafish Proteins
;
genetics
4.Echocardiography-guided percutaneous closure of patent ductus arteriosus without arterial access: Feasibility and safety for a new strategy
Weizhi ZHANG ; Lei GAO ; Wancun JIN ; Qin WU ; Shijun HU ; Yifeng YANG ; Tianli ZHAO
Journal of Central South University(Medical Sciences) 2018;43(9):1000-1006
Objective:To evaluate the feasibility and safety of device closure of patent ductus arteriosus (PDA)using only venous access under echocardiography guidance alone.Methods:A total of 102 consecutive pediatric patients underwent transcatheter PDA closure without arterial access,under the guidance of only echocardiography.The patients were followed up by clinical examination,electrocardiogram,and echocardiogram at 1,3,6 12,and 24 months.Results:Transvenous PDA closure under echocardiographic guidance was successful in 99 (97.1%)patients.There were no acute procedural complications or severe adverse events.The duration ranged from 10 to 65 minutes (median,21 minutes).Immediate complete closure of PDA was achieved in 87 patients (87.9%),and 100% of the patients were completely closed after 24 h.There were no severe adverse events in the period of 1-24 months (median,12 months) follow up.Conclusion:Transvenous PDA closure without fluoroscopy avoids radiation exposure,contrast agent usage and potential arterial complications.It can be used as an alternative procedure,especially for children.
5.Clinical analysis of surgical treatment for aortic coarctation
Wangping CHEN ; Mina JIANG ; Chengming FAN ; Shiyuan TANG ; Yifeng YANG ; Zhongshi WU ; Tianli ZHAO ; Jinfu YANG
Journal of Chinese Physician 2017;19(9):1350-1352,1357
Objective To summarize the methods and experiences of one-stage repair of aortic coarctation.Methods During January 2009 and September 2016,31 patients underwent surgery for coarctation of aorta (COA) in our department.Of them,fifteen patients were accompanied by patent ductus arteriosus (PDA),five associated with ventricular septal defect (VSD),five with VSD and PDA,and six patients were single COA.All patients accepted one-stage repair and follow-up.The surgical strategies and follow-up results were retrospectively reviewed.Results Excision of coarctation and anastomoses was performed in 24 patients,a bypass with artificial graft was performed in 3 patients,longitudinally section transverse suture was performed in 2 patients,and aortoplasty with patch graft was used in 2 patients.Accompanied intracardiac malformations were repaired simutaneously.One patient died of low cardiac output syndrome 1 d after operation.Other patients recovered smoothly.Thirty patients were followed up from 6 months to 7 years.The anastomotic systolic pressure difference disappeared in 21 patients.Eight patients still suffered from systolic pressure difference (5-20 mmHg),but had no need of reoperation.One patient suffered from anastomotic recoarctation 2 years and 3 months after operation and the pressure difference was 48 mmHg.After exerting balloon dilatation,the pressure difference reduced to 17 mmHg.Conclusions Surgery is an effective method of COA treatment.The surgical strategies should be selected according to the characters of coarctation lesions,intracardiac malformations,and the age of patient.
6.First detection of Francisella-like endosymbionts in Hyalomma asiaticum asiaticum from China-Kazakhstan border
Xiaoping YIN ; Shanshan ZHAO ; Dan LIU ; Yanhe TIAN ; Teer BA ; Tianli CHENG ; Jiangguo ZHANG ; Yuanzhi WANG
Chinese Journal of Zoonoses 2017;33(2):170-172,177
We conducted the detection the Francisella spp.nucle acid from Hyalomma asiaticum asiaticum that main distribution is on railway line area from China-Kazakhstan border.The free-living ticks were collected and then identified by morphological and molecular methods.After species identification,they were detected by PCR targeting 16S rRNA and sdhA of Francisella spp.The amplified products were sequenced and the sequences was analyzed by using the Blast.A phylogenetic tree was constructed using MEGA 6 software.A total of 243 fleas were identified as H.asiaticum asiaticum.Only 35 samples were detected for Francisella spp.positive and the positive rate was 14.4%.Sequence analysis showed that two different sequences (seql and seq2) and all belong to Francisella-like endosymbionts (FLEs).Phylogenetic analyses showed that two FLEs were belong to the same cladd.This is first detection of FLEs nucleic acid from H.asiaticum Railway line area of China-Kazakhstan border.
7.Application of perimembranous ventricular septal defects closure solely by femoral vein approach under transesophageal echocardiography guidance
Haisong BU ; Lei GAO ; Weizhi ZHANG ; Qin WU ; Wancun JIN ; Mi TANG ; Tianli ZHAO
Journal of Central South University(Medical Sciences) 2017;42(7):802-807
Objective:To investigate the feasibility and safety of perimembranous ventricular septal defects (PmVSD) closure solely by femoral vein approach under transesophageal echocardiography (TEE) guidance.Methods:From January 1,2014 to May 31,2016,26 patients with PmVSD in Second Xiangya Hospital were selected,with age at 3.2-6.0 (4.3±0.7) years old and body weight at 15.0-19.5 (16.7±1.4) kg.The diameter of VSD was 3.5-4.8 (4.1±0.3) mm.All patients were treated by percutaneous PmVSD closure solely by femoral vein approach under TEE guidance.The effect of the procedure was evaluated by TEE and transthoracic echocardiography (TTE).The clinical follow-up study was conducted by TTE at 1,3,6 and 12 month (s) after the procedure.Results:Twenty cases were successfully treated with percutaneous PmVSD closure solely by femoral vein approach under TEE guidance,and the success rate was 76.9%.Six patients were converted to perventricular closure under TEE guidance because the guide wire in two cases or catheter in other cases could not pass through PmVSD.The diameter of symmetrical VSD occluder was 6.0-7.0 (6.2±0.4) mm.The procedural time was 12.0-64.0 (26.8±6.3) min.The residence time at ICU was 1.8-2.4 (26.8±6.3) h.The in-hospital time was 4.0-5.0 (4.4±0.5) d.There were 3 patients with immediate post-operative trivial residual shunt and incomplete right bundle branch block (IRBBB).All patients survived with no peripheral vascular injury or complications such as tricuspid regurgitation,pericardial tamponade and pulmonary infection.The residual shunt disappeared in 3 patients and IRBBB became normal rhythm in 3 patients at 1 month follow-up time point.No patients suffered from occluder malposition,residual shunt,pericardial effusion,arrhythmia (atrio-ventricular block),aortic valve regurgitation and tricuspid regurgitation.Conclusion:TEE-guided percutaneous PmVSD closureby femoral vein approach is safe and effective.
8.Surgical repair of complete atrioventricular septal defect in 86 patients
Li XIE ; Can HUANG ; Tianli ZHAO ; Jinfu YANG ; Zhongshi WU ; Yifeng YANG ; Fenglin SONG
Journal of Chinese Physician 2016;18(8):1152-1155
Objective To investigate the early surgical outcomes of 86 patients with complete atrioventricular septal defect.Methods Between January 2007 and December 2014,consecutive 86 cases received surgical repair in our department.There were 44 male patients,and 42 female patients.Two-patch repair was performed in 69 cases,and modified single-patch repair in 17 cases.The mean age,height,and weight at the time of operation were (32.3 ± 46.5)months with a range from 1 month to 17 years,(82.1 ±27.6) cm with a range from 53 to 165 cm,and (10.8 ± 8.7) kg with a range from 4.1 to 43 kg,respectively.Rastelli A type was found in 67 cases,B type in 15 cases,and C type in 4 cases.Down's syndrome was complicated in 6 cases.Preoperative mild regurgitation of common atrioventricular valve was shown in 32 cases,moderate regurgitation in 38 cases,and moderate to severe regurgitation in 16 cases.Mild pulmonary hypertension was observed in 15 cases,moderate in 54 cases,and severe in 17 cases.Results After operation,all patients were sent into intensive care units (ICU).The mean duration mechanical ventilation,ICU stay,and hospitalization were (30.9 ± 47.7) h with a range from 2.5 to 244 h,(87.7 ± 76.8) h with a range from 14 to 306 h,and (16.4 ±9.2)d with a a range from 6 to 50 d,respectively.We encountered 4 operatively mortalities (4.7%),including 3 in two-patch repair group,and 1 in modified single-patch repair group.The cause of death was mitral regurgitation.Conclusions Modified single-patch and two-patch technique have a satisfied early outcomes.
9.Effect of C-typenatriuretic peptide on paraquat-induced pulmonary fibrosis in mice
Chen YANG ; Wenjing ZHAO ; Tianli MENG
Chinese Journal of Anesthesiology 2016;36(7):890-892
Objective To evaluate the effect of C-type natriuretic peptide (CNP) on paraquat-induced pulmonary fibrosis in mice.Methods Fifty-four male Kunming mice,aged 8-10 weeks,weighing 30-35 g,were randomly divided into 3 groups (n=18 each) using a random number table:control group (C group),pulmonary fibrosis group (PF group) and CNP group.Paraquat 10 mg/kg (in 0.1 ml of normal saline) was injected intraperitoneally once every 3 days for 5 times in total in PF and CNP groups,and in addition CNP 3 μg/kg (in 0.1 ml of normal saline) was simultaneously injected via the tail vein once every 2 days for 14 times in total in group CNP.The equal volume of normal saline was given instead of paraquat in group C.On days 1,8 and 15 after the end of administation of paraquat,6 mice were sacrificed,and lungs were removed for determination of wet to dry weight ratio (W/D ratio),hydroxyproline (HYP) content (using alkaline hydrolysis),and transforming growth factor-beta 1 (TGF-β1) content (using enzymelinked immunosorbent assay) in lung tissues.Results Compared with group C,the W/D ratio and contents of HYP and TGF-β1 in lung tissues were significantly increased at each time point after the end of administation of paraquat (P<0.05),and the pulmonary fibrosis was obvious in group PF.Compared with group PF,the W/D ratio and contents of HYP and TGF-β1 in lung tissues were significantly decreased at each time point after the end of administation of paraquat (P<0.05),and the pulmonary fibrosis was significantly attenuated in group CNP.Conclusion CNP can reduce paraquat-induced pulmonary fibrosis in mice.
10.Hybrid procedure for infants/children treatment with pulmonary stenosis under transesophageal echocardiographic guidance.
Li XIE ; Can HUANG ; Sijie WU ; Wancun JIN ; Lei GAO ; Qin WU ; Jinfu YANG ; Zhongshi WU ; Tianli ZHAO ; Yifeng YANG ; Fenglin SONG
Journal of Central South University(Medical Sciences) 2016;41(7):691-695
OBJECTIVE:
To investigate the outcomes of hybrid procedure in treating 10 infants/children with pulmonary stenosis under transesophageal echocardiographic guidance.
METHODS:
Between September, 2009 and December, 2015, 10 infants/children underwent hybrid procedure of transthoracic balloon pulmonary valvuloplasty for pulmonary stenosis in the Second Xiangya Hospital, Central South University. The age, height and weight at the time of admission were 0.7-42 (14.8±15.8) months, 53-97 (74.8±16.3) cm, and 4-15.5 (9.3±4.1) kg, respectively. Atrial septal defect, patent foramen ovale, patent ductus arteriosus, muscular ventricular septal defect, persistent left superior vena cava and tricuspid regurgitation were found in 2, 6, 1, 2, 1 and 5 cases, respectively.
RESULTS:
After the operation, all patients were sent into ICU. The mean duration mechanical ventilation, ICU stay and hospitalization were 0.5-41(6.8±12.3) h, 2-85 (31.1±22.8) h, and 6-20 (11.4±5.1) d, respectively. Postoperative transvalvular pressure gradient reduced to 16-45 (31.1±9.8) mmHg, which was decreased significantly compared with that in preoperative (P<0.001). There was no death during hospitalization and follow-up.
CONCLUSION
Hybrid procedure of transthoracic balloon pulmonary valvuloplasty for pulmonary stenosis under transesophageal echocardiographic guidance is a safe and effective treatment.
Child
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Echocardiography, Transesophageal
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Heart Septal Defects, Atrial
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Heart Septal Defects, Ventricular
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Humans
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Infant
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Pulmonary Valve Stenosis
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Treatment Outcome

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