Pulmonary atresia with intact ventricular septum percutaneous radiofrequency-assisted valvotomy and balloon dilation versus surgical valvotomy and Blalock Taussig shunt

OBJECTIVE: We compared the result of radiofrequency (RF)-assisted valvotomy and balloon dilation with closed surgical valvotomy and Blalock Taussig (BT) shunt as primary treatment in selected patients with pulmonary atresia and intact ventricular septum (PA-IVS). BACKGROUND: Patients with PA-IVS who have mild to moderate hypoplasia of the right ventricle (RV) and patent infundibulum have the greatest potential for complete biventricular circulation. The use of RF or laser wires to perforate the atretic valve followed by balloon dilation provides an alternative to surgery. METHODS: Between May 1990 and March 1998, 33 selected patients underwent either percutaneous RF valvotomy and balloon dilation (group 1, n = 21; two crossed over to group 2) or surgical valvotomy with concomitant BT shunt (group 2, n = 14). Second RV decompression by balloon dilation or right ventricular outflow tract (RVOT) reconstruction were performed if necessary. Patients who remained cyanosed were subjected to transcatheter trial closure of the interatrial communication. Partial biventricular repair was offered to those with inadequate growth of the RV. RESULTS: The primary procedure was successful in 19 patients in group 1. There was one in-hospital death and two late deaths. Of the remaining 16 survivors, 12 achieved complete biventricular circulation, 7 of whom required no further interventions. Two patients required repeat balloon dilation, 1 RVOT reconstruction and 2 transcatheter closure of interatrial communication. Two patients underwent partial biventricular repair. In group 2, there were 3 in-hospital deaths after the primary procedure and 1 patient died four months later. All survivors (n = 10) required a second RV decompression, 8 by balloon dilation and 2 by RVOT reconstruction, after which, two patients died. Of the final 8 survivors, 7 achieved complete biventricular circulation, 5 after coil occlusion of the BT shunt and 2 after closure of interatrial communication. CONCLUSIONS: Radiofrequency valvotomy and balloon dilation is more efficacious and safe compared with closed pulmonary valvotomy and BT shunt in selected patients with PA-IVS.     

Formation of in vivo tissue engineered human hyaline cartilage in the shape of a trachea with internal support

OBJECTIVE: Treatment and management of congenital as well as post-traumatic trachea stenosis remains a challenge in pediatric surgery. The aim of this study was to reconstruct a trachea with human nasal septum chondrocytes by using the combination of biodegradable hydrogel and non-biodegradable high-density polyethylene (HDP) as the internal predetermined shape scaffold. METHODS: Human nasal septum cartilage was harvested as excessive tissue after elective septoplasty and digested in 0.6% collagenase II. Chondrocytes were cultured in an equal volume mix of Ham's F12 medium and Dulbecco's modified eagle medium added with 10% fetal bovine serum and basic fibroblast growth factor. After two passages, the cultured chondrocytes were trypsinized and mixed with biodegradable hydrogel Pluronic F127. The chondrocytes-hydrogel admixture was then painted over the HDP as the internal support in a predetermined trachea shape. The composite was then implanted subcutaneously in athymic mice. RESULTS: After 8 weeks of in vivo implantation, the tissue engineered trachea constructs were harvested. Macroscopic appearance of the tissue engineered trachea constructs demonstrated that the HDP were 80-90% covered with yellowish glistering cartilage like tissue without any sign of inflammation. The tissue engineered trachea cartilage consisted of evenly spaced lacunae embedded in basophilic matrix and stained red with Safranin-O staining denoting abundant proteoglycans production. Type II collagen gene which was expressed in native cartilage was highly expressed in this tissue engineered trachea cartilage. CONCLUSION: We have successfully reconstructed a trachea in vivo with human nasal septum chondrocytes using HDP as the internal support. This construct has the advantage of bio-inert and strength in which both are important properties in tracheal reconstruction.     

Human nasal turbinates as a viable source of respiratory epithelial cells using co-culture system versus dispase-dissociation technique

OBJECTIVE: To compare a co-culture system with a conventional dispase-dissociation method for obtaining functional human respiratory epithelial cells from the nasal turbinates for tissue engineering application. METHODS: Human respiratory epithelial cells were serially passaged using a co-culture system and a conventional dispase-dissociation technique. The growth kinetics and gene expression levels of the cultured respiratory epithelial cells were compared. Four genes were investigated, namely cytokeratin-18, a marker for ciliated and secretory epithelial cells; cytokeratin-14, a marker for basal epithelial cells; MKI67, a proliferation marker; and MUC5B, a marker for mucin secretion. Immunocytochemical analysis was performed using monoclonal antibodies against the high molecular-weight cytokeratin 34 beta E12, cytokeratin 18, and MUC5A to investigate the protein expression from cultured respiratory epithelial cells. RESULTS: Respiratory epithelial cells cultured using both methods maintained polygonal morphology throughout the passages. At passage 1, co-cultured respiratory epithelial showed a 2.6-times higher growth rate compared to conventional dispase dissociation technique, and 7.8 times higher at passage 2. Better basal gene expression was observed by co-cultured respiratory epithelial cells compared to dispase dissociated cells. Immunocytochemical analyses were positive for the respiratory epithelial cells cultured using both techniques. CONCLUSION: Co-culture system produced superior quality of cultured human respiratory epithelial cells from the nasal turbinates as compared to dispase dissociation technique.     

Maxillofacial trauma of pediatric patients in Malaysia: a retrospective study from 1999 to 2001 in three hospitals

OBJECTIVE: Maxillofacial trauma in children is not common worldwide. Domestic injuries are frequently seen in younger children while older children are mostly involved in motor vehicle accidents (MVA). The objective of this study was to analyze the pattern of maxillofacial injuries in pediatric patients referred to three government main hospitals in different areas of West Malaysia. METHODS: Patients' records of three selected hospitals in Malaysia (National University of Malaysia Hospital, Kajang Hospital and Seremban Hospital) from January 1999 to December 2001 were reviewed. Data associated with demographics, etiology of injury in relation to age group, type of injuries whether soft tissues of hard tissue in relation to age group and treatment modalities were collected. RESULTS: A total of 521 pediatric patients' records were reviewed. Malays made up the majority of patients with maxillofacial injuries in the three hospitals. Males outnumbered females in all the three hospitals. Injuries commonly occur in the 11-16 years old. MVA was the most common etiology followed by fall and assault. Soft tissue injuries were the most common type of injuries in all the hospitals. In relation to fractures, mandible was the most common bone to fracture with condyle being the most common site. Orbital fracture was the most common fracture in the midfacial area. Most of the fractures were managed conservatively especially in the younger age groups. Open reduction with or without internal fixation was more frequently carried out in the 11-16 years old group. CONCLUSION: Children exhibit different pattern of clinical features depending on the etiology and stage of their bone maturation. A dedicated team, who is competent in trauma and aware of the unique anatomy, physical and psychological characteristics of children, should manage pediatric patient with trauma.     

Initial results and medium-term follow-up of stent implantation of patent ductus arteriosus in duct-dependent pulmonary circulation

OBJECTIVES: This study was designed to assess the safety, efficacy, medium-term outcome, and complications of patent ductus arteriosus (PDA) stenting in duct-dependent pulmonary circulation. BACKGROUND: Patent ductus arteriosus stenting has been proposed as an alternative to surgical shunt on account of postoperative morbidity and complications of surgical shunting. METHODS: Between April 2000 and February 2003, 69 patients with duct-dependent pulmonary circulation underwent cardiac catheterization with the intent of PDA stenting as first palliative procedure. Patients with critical pulmonary stenosis and pulmonary atresia with intact ventricular septum post-radiofrequency valvotomy who had PDA stenting were excluded. Thirteen more patients were excluded because of branch pulmonary artery (PA) stenosis. The follow-up was by clinical examination, echocardiography, and repeat cardiac catheterization at six to nine months following the procedure. RESULTS: Patent ductus arteriosus stenting was successful in 51 patients (91.1%) and failed in 5 patients (8.9%). The mean narrowest PDA diameter was 1.9 +/- 0.6 mm. The mean procedure and fluoroscopy time were 95.7 min and 29.4 min, respectively. In one patient the stent dislodged and migrated to the left femoral artery and another patient developed transient intravascular hemolysis. There was no procedure-related mortality. Three patients (5.9%) died one day to two months after the procedure. At follow-up (3.2 months to 2.4 years), 8 patients developed significant stent stenosis requiring reintervention. Seven patients developed worsening of preexisting branch PA stenosis. The freedom from reintervention was 89% and 55% at 6 months and 1 year, respectively. CONCLUSIONS: Patent ductus arteriosus stenting is an attractive alternative to surgical shunt in a majority of patients with duct-dependent circulation. An absolute contraindication to this technique is the presence of branch pulmonary stenosis.     

Population data of 21 autosomal STR loci in Malaysian populations for human identification

International Journal of Legal Medicine - The use of 21 autosomal STR loci for human identification has been gaining popularity throughout the world. It has been indicated that the forensic...     

Early and midterm outcome of complete Atrioventricular Septal Defect (AVSD) in a single institution

Background

Surgical repair of complete atrioventricular septal defect is a well established procedure performed in young children. We sought to determine the rate of survival, reoperation and occurrence of Left Atrioventricular Valve Regurgitation (LAVVR).

Patients and methods

This was a retrospective review of 56 patients with Complete Atrioventricular Septal Defect (CAVSD) recruited from January 2000 till July 2010. Sixty-six percent of these patients had Down’s Syndrome. The median age and weight at surgery was 0.95?±?2.7 years and 6.2?±?7.5 kg respectively. 2D Echocardiography was used to quantify the degree of LAVVR pre and postoperatively. The technique of repair used was either 2 patch, modified single patch or single patch. The cleft in the LAVV was closed in all cases. Risk factors associated with increased mortality and re-intervention were analyzed.

Results

The operative mortality was 5.4 %. There were 3 patients who developed complete heart block and required Permanent Pace Maker (PPM) implantation whereas 11 patients (20 %) developed supraventricular arrhythmia. Twenty-one percent of patients had moderate LAVVR at discharge. Eight patients (14 %) required re-operation for LAVV regurgitation at a mean duration of 17?±?29 months. The mean ICU stay was 6 days. Prolonged ventilation and presence of infection trended towards higher mortality. The presence of moderate or severe LAVVR at discharge was one of the main factors for re-intervention.

Conclusion

The surgical repair of Complete Atrioventricular Septal Defect in young children is associated with acceptable mortality and morbidity. Left atrio-ventricular valve regurgitation remains the most common residual defect and significantly associated with re-intervention.