ObjectiveThe full name of vertebroplasty is percutaneous vertebroplasty (PVP). It is a clinical technique that injects bone cement into the diseased vertebral body to achieve strengthening of the vertebra. The research on the safety and efficacy of bone cement is the basis for clinical application. In this study, vertebroplasty is used to evaluate and compare the safety and efficacy of Tecres and radiopaque bone cement in experimental pigs, and to determine the puncture method suitable for pigs and the pre-clinical evaluation method for the safety and efficacy of bone cement. MethodsTwenty-four experimental pigs (with a body weight of 60-80 kg) were randomly divided into an experimental group (Group A) and a control group (Group B). Group A was the Tecres bone cement group, and Group B was the radiopaque bone cement group, with 12 pigs in each group. Under the monitoring of a C-arm X-ray machine, the materials were implanted into the 1st lumbar vertebra (L1) and 4th lumbar vertebra (L4) of the pigs via percutaneous puncture using the unilateral pedicle approach. The animals were euthanized at 4 weeks and 26 weeks after the operation, respectively. The L4 vertebrae were taken for compressive strength testing, and the L1 vertebrae were taken for hard tissue pathological examination to observe the inflammatory response, bone necrosis, and degree of osseointegration at the implantation site. ResultsThe test results of compressive strength between groups A and B showed no significant difference at 4 weeks and 26 weeks after bone cement implantation (P > 0.05). Observation under an optical microscope (×100) revealed that at 4 weeks postoperatively, both groups A and B showed that the bone cement was surrounded by proliferative fibrous tissue, with lymphocyte infiltration around it. The bone cement was combined with bone tissue, the trabecular arrangement was disordered, and osteoblasts and a small amount of osteoid were formed. At 26 weeks postoperatively, bone cement was visible in both groups A and B. The new bone tissue was mineralized, the trabeculae were fused, the trabecular structure was regular and dense with good continuity, and no obvious inflammatory reaction was observed. ConclusionIn experimental pig vertebrae, there were no significant differences observed in the compressive strength, inflammation response, bone destruction, and integration with the bone between Tecres and non-radiopaque bone cement. Both exhibited good biocompatibility and osteogenic properties. It indicates that using vertebroplasty to evaluate the safety and efficacy of bone cement in pigs is scientifically sound.

Objective To summarize the technique and clinical experience of hybrid procedure under cardiopulmonary bypass (CPB) in children with muscular ventricular septal defect (mVSD). Methods From January 2006 to June 2010, 45 cases of mVSD underwent hybrid procedure with CPB. mVSDs were closed with devices under direct vision in 45 cases. Of them, there were 20 males and 25 females. They ranged from 52 days to 12 years [mean (2.05 ±2.48) year] in age and from 3 to 30 kg [(11.93 ±7.70)kg] in body weight. Preoperatively, most of children were highly susceptible to respiratory tract infections. The hybrid approach was used in all patients with CPB under the guidance of transesophageal echocardiography (TEE). The diameter of mVSDs ranged from 2 to 7 mm under TEE. Of 45 cases, 40 patients had increased rates of pulmonary blood flow. 29 patients had left axis deviation and 12 cases had sinus arrhythmia on electrocardiography (ECG). 19 had other congenital heart lesions, including transposition of great arteries in 1 case, tetralogy of Fallot in 2, pulmonary artery stenosis in 3, patent ductus arteriosus in 6, atrial septal defects in 6) and aorta coactation in 1. The quantity of VSDs were from 1 to 7 (single, in 7; two, in 24 case; three, in 8 case; four, in 5 case and seven, in lease. 37 patients were combined with pulmonary hypertension in our cohort. 38 patients with another large VSD and 19 with other congenital heart lesions were required surgical repair at sometime. Results The hybrid procedures were undertaken in all 45 cases of this cohort. All cases were successful and no deaths occurred during operation. A total of 48 devices were implanted in 45 patients, including single devices in 42 cases (device size ranged from 4 to 10 mm) and two devices in 3 cases (device size ranged from 4 -7 mm). The average time on CPB was (58.28 ±20.70) min , while aortic crossclamp time was(34. 94 ± 14.75) min. In addition, the time on mechanical ventilation postoperatively ranged from 2 hours to 6 days. Compared to the older children, 20 infante aged less than 8 monhad a significant difference in cardiac function in the early postoperative period. One infant was given up treatment because of serious infection. Anather cases recovered with the use of supportive treatment, such as using vasoactive agents, digoxin, inhaling nitric oxide, diuresis, and so on. The enteric-coated aspirin was given at dose of 5 mg ? kg -1. day -1 for a period of 3 to 6 months as usual postoperatively. All patients attended follow-up at 1 week, 1 month, 3 months, 6 months, 1 year and 2 years post-procedure. No major complications were encountered during this period. All cases were no instance of migration of any of the devices, residual shunt, aortic regurgitation, atrioventricular valve dysfunction, Ⅲo atrial-ventricular conduction block, new arrhythmia, and so on. There are no death in long-term follow-up. Conclusion Hybrid procedure is safe and effective for the closure of congenital heart defects in children.