ABSTRACT
Objective To compare the mid-term outcomes of valved bovine jugular vein conduit and autologous pericardium conduit in reconstruction of right ventricular outflow tract. Methods Eighteen congenital heart disease patients were implanted with external conduits (included 11 valved bovine jugular vein conduits and 7 autologous pericardium conduits) for right ventricular outflow tract reconstruction between May 2013 and Jul. 2016. There were 11 males and 7 females at age of 2-16 (5.22±4.12) years. Preoperative clinical diagnoses included pulmonary artery atresia with ventricular septal defect (n＝7), double outlet of right ventricle with pulmonary stenosis (n＝4), persistent truncus arteriosus (n＝3), persistent truncus arteriosus with absence of right pulmonary artery (n＝1), corrected transposition of great arteries with pulmonary stenosis (n＝1), and transposition of great arteries with pulmonary stenosis (n＝2). The perioperative status was recorded. The cardiac ultrasound and computed tomography angiography (CTA) were used to evaluate the efficacy during 4-56 months of follow-up. Results There were no perioperative deaths in the bovine jugular vein conduit group, and 2 deaths in the autologous pericardium conduit group. One died of pulmonary hypertension crisis and the other died of low cardiac output syndrome. The ratio of right ventricular pressure to radial arterial pressure, duration of mechanical ventilation and intensive care unit (ICU) stay after surgery were significantly lower in the bovine jugular vein conduit group than those in the autologous pericardium conduit group (all P0.05). There were no significant differences in extracorporeal circulation time, aortic cross-clamping time, transvalvular gradient in right ventricular outflow tract, blood consumption or total hospitalization costs between the two groups (all P0.05). During follow-up, there were no deaths in the two groups, no reoperations in the bovine jugular vein conduit group, and 1 case received reoperation 2 years after surgery due to severe right ventricular dysfunction in the autologous pericardium conduit group. In the bovine jugular vein conduit group, the transvalvular gradients in right ventricular outflow tract at the last follow-up and before discharge were (22.91±7.31) mmHg (1 mmHg＝0.133 kPa) and (20.45±6.70) mmHg, respectively, and the difference was not significant (P0.05). In the autologous pericardium conduit group, the transvalvular gradient in right ventricular outflow tract was (29.20±18.09) mmHg at the last follow-up and (16.14±4.02) mmHg before discharge, and the difference was significant (P0.05). At the last follow-up after surgery, there were 8 cases of mild reflux and 3 cases of moderate reflux in the bovine jugular vein conduit group, and 1 case of mild reflux, 2 cases of moderate reflux and 2 cases of severe reflux in the autologous pericardium conduit group, and the difference between the two groups was significant (P0.05). Postoperative ultrasonography showed the thickened valve leaflets with good valve movement in the bovine jugular vein conduit. No calcification, thrombosis and infective endocarditis were found in the two groups. Postoperative cardiac CTA found that there was aneurysmal dilatation in 1 middle segment and 1 proximal anastomotic stoma of the bovine jugular vein conduit group, and no dilatation in the autologous pericardium conduit group. Conclusion Domestic valved bovine jugular vein conduit is suitable for right ventricular outflow tract reconstruction in patients with complex congenital heart malformations. Mid-term follow-up shows that bovine jugular vein conduit has good anti-reflux performance and no severe obstruction or calcification. It is obviously superior to autologous pericardium conduit. However, some bovine jugular vein conduits have aneurysmal dilatation in mid-term follow-up, which needs to be further improved.
ABSTRACT
Objective To compare the clinical efficacy of BalMedic bovine jugular vein conduit (BalMedic) with homograft in right ventricular outflow tract reconstruction.Methods Totally 10 patients were implanted homograft to reconstruct right ventricular outflow tract,while 14 patients were implanted BalMedic from January 2003 to July 2009,and the function of the implanted conduit was evaluated by Doppler echocardiography one year after operation.Results 9 patients in group Homograft were cured,while 1 patient died of multiple organ failuie caused by infective endocarditis,which was confirmed associated to the conduit.13 patients in group BalMedic were cured,while 1 patient died of heart failure 2 days after operation,which no independent with the conduit.No stenosis of the pulmonary valve and further stoma had been found in both two groups,and they were no significant different( P ＞0.05 ).There were no thrombus aud aneurysm in both two groups.Two patients in group Homograft had low-grade regurgitation with pulmonary valve,while one had middle-grade regurgitation.And 4 patients in group BalMedic had low-grade regurgitation with pulmonary valve,no else became worse.Conclusion Both homograft and BalMedic can be used in reconstruction of right ventricular outflow tract.BalMedic may have better prospect.
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Objective Xenografts have poor biocompatibilities,the aim of this study was to improve the biocompatibilities of decellular xenografts via heparin/dihydroxy-iron complex multilayeres (HDCMs) nanomodification.Methods A novel thrombo-resistant surface for decellular xenograft had been developed by alternating linkage of dihydroxy-iron and heparin to decellular bovine jugular vein (DC-BJV),and surface characterization and biocompatibility of HDCMs nanomodified BJV (HDCMs-BJV) were detected.Results Toluidine blue colorimetric method showed the amount of linked heparin was about (808 ±86) μg/cm2 per assembly-cycle.SEM images proved HDCMs were uniformly linked to and formed nanoscale films around the fibrils of DC-BJV.Washing test proved HDCMs were firmly linked to BJV and sustainedly released heparin for a long time.Tensile test showed that biomechanical stability was increased.Antithrombogenicity test showed that the activated partial thrombin time (APTT) and prothrombin time (PT) of all trial groups were above the normal reference ranges.Platelet adhesion test evaluated mean platelet count per 10 000 μm2 area was 8 ±4 for HDCMs-BJV vs.48 ± 16 for DC-BJV.Endothelial cells (ECs) proliferation test showed the number and activity of ECs on luminal surface of HDCMs-BJV were very similar to DC-BJV at 7-day incubation.Calcium content assay evaluated mean calcium content was ( 8.5 ± 1.9 ) μg/mg dry weight for HDCMs-BJV vs.(26.6 ± 3.7) μg/mg dry weight for DC-BJV at 4 weeks and (21.5 ± 6.8 ) μg/mg dry weight for HDCMsBJV vs.( 112.6 ± 16.9) μg/mg dry weight for DC-BJVs at 8 weeks,respectively.Conclusion These results demonstrate HDCMs were firmly linked to BJV and formed nanoscale thrombo-resistant films,and HDCMs nanomodification improves biocompatibilities of decellular xenograft.
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Objective To increase the mechanic characteristic of bovine jugular veins conduit (BJVC) by combined knitted stent outside made of nylon fiber. Methods Get rid of the cells of BJVC by enzymolysis, then combined a fabric stent with a acellular bovine jugular vein conduit that cross-linked dealed by photooxidation method to improve the mechanic function of BJVC. To compare the mechanical function and histology change of BJVC combined with fiber stent outside with that of BJVC only without stent. BJVC combined with fiber stent outside was divided into experiment group and the latter into control group. Two roller pumps on cardiopulmonary bypass unit were designed to simulate the pulmonary circulation. One produce the stream, and the other assist to bring a certain pressure by regulating a degree of tightness. The pressure of forward stream was used in messuring extension rate and leakage volume of two BJVC groups, and the pressure of backward stream was used in messuring the regurgitation volume. Results Set the formula to calculate the rate of variation of BJVC diameter under a certain pressure or not. The experiment group extension rate was zero under pressure of 10-20 mm Hg, about ( 7.7 ± 2.3 ) % under pressure of 40 mm Hg, until 60 mm Hg to ( 11.4 ± 3.1 ) %. While the control group reached about ( 14.8 ± 4.7 ) % at 20mm Hg already. There was no regurgitation volume of the experiment group under pressure of 30 mm Hg vs. the control group' s reached 34ml/min at 30 mm Hg while the two groups were same under pressure that lower than 20 mm Hg. When the pressure higher, the difference between the two groups more notable. There was no leakage of the BJVCs with fabric stent till pressure from 40 mmHg to 60mmHg, vs. the control group 1,5, 13 ml/min at pressure 30, 40, 60 mm Hg. Except the regurgitation and leakage volumes under pressure at 10 -20 mm Hg, as the two numerical values were both zero that can not be caculated by the statistic software, the differences of the two groups above had statistics significance. In vivo, 9 dogs received bovine jugular vein conduit transplant procedure to observe the mechanic fnction and tissue reaction. Five adopted B.JVC with stent and four just BJVC only. Six month later after the transplant procedure, there was no significant difference between the two groups but more inflaming cells than the former group, especially at the location round the nylon fibers. Through the observation in HE stain, that was considered as foreign body reaction. Conclusion Fabric stent can improve the mechanical function of BJVC and relatively easy to get.