Multimodality imaging in the assessment of thoraco-omphalopagus conjoined twin: lessons to learn.

Conjoined twins are rare and present a unique challenge to pediatric surgeons and radiologists. An imaging strategy to accurately define anatomic fusion, vascular anomalies, and other associated abnormalities is important for surgical planning and prognostic information. A conjoined female twin with a combined weight of 2.8 kg was born by emergency caeserean. Hence, a computed tomography scan of the thorax and entire abdomen at 1.25 mm slice thickness was performed to delineate the internal structures of the twins. CT-angiography defined specific vascular supply which determined the distribution of shared structures between the twins. An echocardiogram showed four heart chambers with atrioventricular septal defect. To further evaluate the heart chambers, the twin was planned for gated cardiac magnetic resonance imaging. Unfortunately, they succumbed 6 hours apart due to complication of septicemia. Magnetic resonance imaging and CT scan provide excellent anatomic detail, demonstrating organ position, shared viscera, and limited vascular anatomy, whilst angiography defined specific vascular supply, useful in determining the distribution of shared structures between the twins in planning for surgery.

Predictors of failed closure of patent ductus arteriosus with indomethacin.

INTRODUCTION: The aim of this study was to determine predictors of failed closure of patent ductus arteriosus (PDA) following a single course of indomethacin in symptomatic preterm infants. METHODS: This prospective observational study was carried out on 60 preterm infants weighing less than 1,750 g with symptomatic PDA confirmed by echocardiography. At a median age of 7.0 days (interquartile range 4.0), they were given indomethacin of 0.1 mg/kg/day intravenously daily for six days. Closure of PDA was reassessed by echocardiography upon completion of therapy. RESULTS: The PDA of 40 percent (n=24) of these infants remained patent. Forward logistic regression analysis showed that the only significant predictors of failed PDA closure in these infants were: PDA size (adjusted odds-ratio [OR] is 7.0; 95 percent confidence interval [CI] of OR is 2.0, 24.8; p-value is 0.002), birth weight (adjusted OR is 0.996; 95 percent CI of OR is 0.993, 1.000; p-value is 0.03) and platelet count (adjusted OR is 0.987; 95 percent CI is 0.975, 1.000; p-value is 0.045). Gestational age, maternal age and left atrium/aorta ratios were not significant predictors. CONCLUSION: Larger PDA, lower birth weight and lower platelet count were significant predictors of high failure in indomethacin therapy given late at one week of life.

Do paediatric research presentations at local meetings get published?

Accessibility of research done locally to clinicians remains limited unless it is in the published form. The publication rate of research presentations at the Annual Malaysian Paediatric Association, Perinatal Society of Malaysia and Academy of Medicine Malaysia in 1997 and 1998 was determined. One hundred and five (95.5%) of 110 research presentations were carried out in Malaysia. Thirty-seven (35.2%) presentations were published. University-affiliated institutions were more likely to publish their research presentations as compared to Ministry of Health hospitals (OR 3.1 95% CI 1.4-6.8, p < 0.01). There is a need to encourage publication of local research presentations. University-affiliated institutions performed better due to institution pressure for career advancement.

The Amplatzer duct occluder: experience in 209 patients.

OBJECTIVES: The aim of the study was to assess the safety and efficacy of the Amplatzer ductal occluder (ADO) in transcatheter occlusion of patent ductus arteriosus (PDA). BACKGROUND: Transcatheter closure of small to moderate sized PDAs is an established procedure. The ADO is a self-expandable device with a number of salutary features, notably its retrievability, ease of delivery via small 5F to 7F catheters and a range of sizes suitable even for the larger PDAs. METHODS: Between November 1997 and August 1999, the ADO was successfully implanted in 205 of 209 patients with PDA. The inclusion criteria for this device occlusion method were patients with clinical and echocardiographic features of moderate to large PDA, weighing > or =3.5 kg as well as asymptomatic adolescents and adults with PDA measuring > or =5.0 mm on two-dimensional (2D) echocardiogram. Occlusion was achieved via the antegrade venous approach. Follow-up evaluations were performed with 2D echocardiogram, color-flow mapping and Doppler measurement of the descending aorta and left pulmonary artery velocity at 24 h and 1, 3, 6 and 12 months after implantation. RESULTS: Two hundred and five patients had successful PDA occlusion using this device. The patients were between two months and 50 years (median 1.9) and weighed between 3.4 kg and 63.2 (median 8.4). Infants made up 26% of the total patients. The PDA measured from 1.8 to 12.5 mm (mean 4.9) at the narrowest diameter. Forty-four percent of patients achieved immediate complete occlusion. On color Doppler the closure rates at 24 h and 1 month after implant were 66% and 97%, respectively. At 6 and 12 months all except one patient attained complete occlusion. Device embolization occurred in three patients; in two this was spontaneous, and in the other it was due to catheter manipulation during postimplant hemodynamic measurement. Mild aortic narrowing was seen in an infant. CONCLUSIONS: Patent ductus arteriosus occlusion using ADO is safe and efficacious. It is particularly useful in symptomatic infants and small children with relatively large PDA. Embolization can be minimized by selection of appropriate sized devices, and caution should be exercised in infants <5 kg.

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.