OBJECTIVE To investigate the methods to fabricate repair materials of tissue engineered peripheral nerve with bioactivity of Schwann cells (SC). METHODS 1. The materials were made by dry-wet spinning process to fabricate PLA hollow fiber canal with external diameter of 2.3 mm, internal diameter of 1.9 mm, thickness of 0.4 mm, pore size of 20 to 40 microns, pore ratio of 70% and non-spinning fiber net with pore size of 100 to 200 microns, pore ratio of 85%. 2. SC were implanted into excellular matrix (ECM) gel to observe the growth of SC. 3. SC/ECM complex were implanted into non-spinning PLA fiber net to observe the growth of SC. 4. SC, SC/ECM and SC/ECM/PLA were implanted into PLA hollow fiber canal to bridge 10 mm defect of rat sciatic nerve. RESULTS 1. SC were recovered bipolar shape at 1 day after implantation, and could be survived 14 days in ECM gel. 2. After SC/ECM complex was implanted into PLA net, most of SC were retained in the pore of PLA net with the formation of ECM gel. SC could be adhered and grown on PLA fiber. 3. Most of SC in ECM gel could be survived to 21 days after transplantation. Survival cell numbers of SC/ECM and SC/ECM/PLA groups were obviously higher than SC suspension group. CONCLUSION Non-spinning PLA porous biodegradable materials with ECM is benefit for SC to be adhered and grown.
ObjectiveTo summarize the applications of Schwann cells (SCs), stem cells, and genetically modified cells (GMCs) in repair of peripheral nerve defects. MethodsThe literature of original experimental study and clinical research related with SCs, stem cells, and GMCs was reviewed and analyzed. ResultsSCs play a key role in repair of peripheral nerve defects; the stem cells can be induced to differentiate into SCs, which can be implanted into nerve conduits to promote the repair of peripheral nerve defect; genetically modified technology can enhance the function of SCs and different stem cells, which has been regarded as a new option for tissue engineered nerve. ConclusionAlthough great progress has been made in tissue engineered nerve recently, mostly limited to the experimental stage. The research of seed cells in application of tissue engineered nerve need be studied deeply.
Objective To investigate the hemocompatibility of the acellular valved bovine jugular vein conduit (BJVC) treated with polyepoxy compound (PC), and discuss its application in cardiovascular surgery and tissue engineering in the future. Methods BJVC treated with PC was regarded as the experiment group and BJVC treated with glutaraldehyde (GA) was considered to be the control group. Rat blood was used for in vitro hemolytic test to calculate hemolytic rates of BJVC, and curve of absorbanceclotting time was drawn. Human blood was used to determine the level of D-dimeride and complement activation C3a des Arg, and test its hemocompatibility in vitro. We divided 20 canines into the experiment group (PC group, n=10) and the control group (GA group, n=10) by random digital table. The BJVC treated with PC or GA were implanted between the pulmonary artery and right ventricle. Ten months after the implantation, thrombus and histological observation were performed to evaluate the blood compatibility in vivo. Results The hemolytic rate in the PC group (0.23%) was lower than that in the GA group (0.35%), which was in accordance with the national standard of hemolytic test (lt;5%). The curve of absorbanceclotting time in the experiment group declined more slowly than that of the control group. The D-dimeride level in the experiment group was significantly lower than that of the control group (0.10±0.01 μg/ml vs. 0.12±0.02 μg/ml , t=3.277, P=0.004), but both of them were within the normal level. The level of complement C3a des Arg in the experiment group was significantly lower than that of the control group (0.74±0.09 μg/ml vs. 1.02±0.19 μg/ml, t=4.183, P=0.001). Eight canines survived 10 months after the implantation in both the two groups, and two other canines in each group died due to ventricular fibrillation. Three canines were discovered to have thrombus in the control group while no thrombus was observed in the experiment group. Conclusion Compared with GA, acellular BJVC treated with PC has superiority in hemocompatibility in vitro and vivo, and has potential application in clinical research and practice.
ObjectiveTo summarize the research progress of autologous vein nerve conduit for the repair of peripheral nerve defect. MethodsThe recent domestic and foreign literature concerning autologous vein nerve conduit for repair of peripheral nerve defect was analyzed and summarized. ResultsA large number of basic researches and clinical applications show that the effect of autologous venous nerve conduit is close to that of autologous nerve transplantation in repairing short nerve defect, especially the compound nerve conduit has a variety of autologous nerve tissue, cells, and growth factors, etc. ConclusionAutologous vein nerve conduit for repair of non-nerve defect can be a good supplement of autologous nerve graft, improvement of autologous venous catheter to repair peripheral nerve defect is the research direction in the future.
Objective To investigate the surgery experience of modified intra/extracardiac conduit total cavopulmonary connection (TCPC). Methods We retrospectively analyzed clinical data of 47 patients of complex congenital heart disease undergoing intra/extracardiac conduit total cavopulmonary connection in our hospital between January 2008 and December 2015. There were 29 males and 18 females with a median age of 7 years (range 4 to 9 years) and median body weight of 22 kg (range 14 to 38 kg). The heart echocardiography and cardiac imaging confirmed diagnosis suitable for TCPC surgery. Results There was no early death in the whole group. The mean pulmonary arterial pressure was 16 (12–20) mm Hg and the ventilation time was 14 (7–97) h. The main complications were intractable pleural effusion in 7 patients, low cardiac output syndrome in 3 patients, repeated supraventricular tachycardia in 1 patient. All the patients recovered after treatment. At the end of discharge, the percutaneous oxygen saturation was 85%–96% (92.6%±3.3%). The echocardiography showed the conduit pressure was 0–2 mm Hg. Patients were followed up for 1 to 7 years. Three patients were lost. One patient had intestinal nutrition loss, receving repeated pleural effusion, the treatment was ineffective, died after 4 years. Four patients of repeated pleural effusion improved after treatment. One patient repeated attacks supraventricular tachycardia within 1 year, controlled by amiodaronum, already stopped about 28 months. No recurrence occurred. All survivors were in New York Heart Association (NYHA) functional class Ⅰ or Ⅱ, with good activity tolerance. Conclusion The modified intra/extracardiac conduit TCPC combines the advantages of both the lateral tunnel and the extracardiac conduit. The operation is simple, used in the treatment of complex congenital heart disease. The short-term and mid-term results are encouraging.
The choice of the graft conduit for coronary artery bypass grafting (CABG) has significant implications both in the short-and long-term. The patency of a coronary conduit is closely associated with an uneventful postoperative course, better long-term patient survival and superior freedom from re-intervention. The internal mammary artery is regarded as the primary conduit for CABG patients, given its association with long-term patency and survival. However, long saphenous vein (LSV) continues to be utilized universally as patients presenting for CABG often have multiple coronary territories requiring revascularization. Traditionally, the LSV has been harvested by creating incisions from the ankle up to the groin termed open vein harvesting (OVH). However, such harvesting methods are associated with incisional pain and leg wound infections. In addition, patients find such large incisions to be cosmetically unappealing. These concerns regarding wound morbidity and patient satisfaction led to the emergence of endoscopic vein harvesting (EVH). Published experience comparing OVH with EVH suggests decreased wound related complications, improved patient satisfaction, shorter hospital stay, and reduced postoperative pain at the harvest site following EVH. Despite these reported advantages concerns regarding risk of injury at the time of harvest with its potential detrimental effect on vein graft patency and clinical outcomes have prevented universal adoption of EVH. This review article provides a detailed insight into the technical aspects, outcomes, concerns, and controversies associated with EVH.
Objective To introduce a modified technique of right ventricular outflow tract (RVOT) reconstruction using a handmade bicuspid pulmonary valve crafted from expanded polytetrafluoroethylene (ePTFE) and to summarize the early single-center experience. Methods Patients with complex congenital heart diseases (CHD) who underwent RVOT reconstruction with a handmade ePTFE bicuspid pulmonary valve due to pulmonary regurgitation at Guangdong Provincial People’s Hospital from April 2021 to February 2022 were selected. Postoperative artificial valve function and right heart function indicators were evaluated. Results A total of 17 patients were included, comprising 10 males and 7 females, with a mean age of (18.18±12.14) years and a mean body weight of (40.94±19.45) kg. Sixteen patients underwent reconstruction with a handmade valved conduit, with conduit sizes ranging from 18 to 24 mm. No patients required mechanical circulatory support, and no in-hospital deaths occurred. During a mean follow-up period of 12.89 months, only one patient developed valve dysfunction, and no related complications or adverse events were observed. The degree of pulmonary regurgitation was significantly improved post-RVOT reconstruction and during follow-up compared to preoperative levels (P<0.001). Postoperative right atrial diameter, right ventricular diameter, and tricuspid regurgitation area were all significantly reduced compared to preoperative values (P<0.05). Conclusion The use of a 0.1 mm ePTFE handmade bicuspid pulmonary valve for RVOT reconstruction in complex CHD is a feasible, effective, and safe technique.
ObjectiveTo summerize the early results of total cavopulmonary connection (TCPC) procedure with an extracardiac conduit in adults with congenital heart disease, and assess risk factors for postoperative delayed recovery in ICU. MethodsWe retrospectively analyzed the clinical data of 20 adult patients underwent TCPC operation with extracardiac conduit in Fu Wai Hospital between January 2012 and December 2014. There were 14 female and 6 male patients at age of 16 to 33 (20.45±4.33) years. ResultsThere was no hospital mortality. The time of ICU stay was 4.4±1.7 days. And time of hospital stay was 32.5±21.6 days. Morbidities included prolonged pleural effusion lasting more than 7 days in 12 patients (60.0%), new arrhythmias in 3 patients (15.0%), reexploration for bleeding in 3 patients (15.0%), surgical wound poor healing in 1 patient (5.0%). Dopamine and calcium were used in all the patients in the ICU, epinephrine in 18 patients, milrinone in 11 patients. Risk factors for postoperative delayed recovery in ICU were preoperative arrhythmias (P=0.02), cardiopulmonary bypass time longer than 120 min (P=0.04), plasma applications more than 2 000 ml (P=0.01), absence of fenestration (P=0.04), and pleural effusion lasting longer than 7 days (P=0.04). ConclusionThe TCPC procedure with an extracardiac conduit can be performed in adults with encouraged early results. Actively vasoactive drugs to maintain circulation early in ICU has good results for the patient's recovery.
Objective Comparing postoperative change of blood gas and hemodynamic status in patients underwent a right ventricletopulmonary artery (RVPA) conduit or a modified BlalockTaussig (mBT) shunt for pulmonary atresia with ventricular septal defect and without major arterial pulmonary collaterals (MAPCAs), to affirm the effect on oxygen supply /demand with different procedure. Methods From July 2006 to October 2007, 38 patients with pulmonary atresia and ventricular septal defect without MAPCAs were divided into two groups according to different procedures: RVPA group (n=25) and mBT group (n=13).Perioperative mortality, blood gas and hemodynamic data during postoperative 48 hours, including heart rate, blood pressure, systemic oxygen saturation, mixed venous oxygen saturation, oxygen excess factor, inotropic score were compared in both groups. Results The difference in the mortality between RVPA group (4.0％，1/25) and mBT group （7.7％，1/13) showed no statistical significance（Pgt;0.05）. The total of 33 patients were followed up, the followup time was from 6 to 18 months.11 patients (4 patients in mBT group, 7 patients in RVPA group) underwent corrected procedures during 9 to 18 months after palliative procedures, one case died of elevated pulmonary vascular resistance and right ventricle failure. The mixed venous oxygen saturation at 24h and 48h after surgery were higher than that at 6h after surgery (Plt;0.01) both in RVPA group and mBT group. The systolic blood pressures at 6h, 24h, 48h after surgery in RVPA group were lower than those in mBT group (P=0.048，0.043， 0.045)，the mean systemic blood pressures in RVPA group were higher than those in mBT group (P=0.048, 0.046, 0.049),the diastolic blood pressures in RVPA group were higher than those in mBT group (P=0.038, 0.034, 0.040)， the inotropic scores in RVPA group were lower than those in mBT group (P=0.035， 0.032，0.047). Conclusion The blood pressures and inotropic scores are found significantly different in RVPA conduit and mBT procedures, while postoperative systemic oxygen delivery areequivalent. Both RVPA and mBT patients decline to nadir in hemodynamic status at 6 h after surgery.
ObjectiveTo investigate the impact of graft type on perioperative outcomes and long-term prognosis in patients undergoing surgical repair of post-myocardial infarction ventricular septal rupture (VSR) with concomitant coronary artery bypass grafting (CABG). MethodsA retrospective analysis was conducted on clinical data from patients who underwent VSR repair and simultaneous CABG at Fuwai Hospital between 2005 and 2022. Patients were divided into an arterial graft group and a saphenous vein graft (SVG)-only group based on the type of bypass grafts used. Clinical outcomes were compared between the two groups. ResultsA total of 92 patients were included, comprising 56 males and 36 females, with a mean age of (62.4±7.9) years. The arterial graft group consisted of 60 patients, and the SVG-only group consisted of 32 patients. There were no statistical differences between the two groups in baseline characteristics, time interval from myocardial infarction to surgery, or culprit vessel distribution (P>0.05). A higher proportion of patients in the SVG-only group received preoperative intra-aortic balloon pump (IABP) support (56.3% vs. 35.0%, P=0.049). However, cardiopulmonary bypass time, aortic cross-clamp time, and early mortality rates were similar between the two groups (P>0.05). Follow-up data revealed no statistically significant differences in cumulative 10-year survival (82.8% vs. 80.0%, P=0.940) or freedom from major adverse cardiovascular and cerebrovascular events (MACCE) (49.6% vs. 58.6%, P=0.491) between the SVG-only and arterial graft groups. Furthermore, graft type did not significantly affect long-term mortality in patients with a culprit vessel in the left anterior descending artery or those with multivessel disease. ConclusionIn patients undergoing delayed repair of VSR with concomitant CABG, the use of arterial or saphenous vein grafts did not significantly impact perioperative outcomes or long-term prognosis. Future research should further explore the benefits of different revascularization strategies to optimize treatment for this population.