Complete heart block in children at King Chulalongkorn Memorial Hospital.

The etiologies of complete heart block in thirty-one children (mean age 5.5 +/- 5.2 years, range 0-14 years) diagnosed at King Chulalongkorn Memorial Hospital between 1990-2001 were reviewed. Three main groups of patients were identified: 1) patients who presented in utero or in the newborn period (congenital heart block, n = 6), 2) patients who had complete heart block after cardiac surgery (postoperative heart block, n = 10), and 3) children outside the newborn period with a new diagnosis of complete heart block unrelated to cardiac surgery (unknown etiology, n = 15). Among 15 patients in the last group, 5 were asymptomatic (or minimally symptomatic) with complete heart block unexpectedly found. These patients probably had previously undetected congenital heart block. Two patients had complete heart block associated with mild viral illness, but no bradycardia-related symptom. The etiology for heart block in these 2 patients was unknown. Eight patients probably had recent onset heart block because of new bradycardia-related symptoms, or a previously documented normal heart rate. All patients in this group were female (mean age 4.3 +/- 4.3 years, median 3.5 years). All were diagnosed between August and January, and the majority (75%) had a history of non-specific viral illness in the preceding 2 weeks. Seven patients (87.5%) were acutely symptomatic. Syncope and/or seizure were the most common presenting symptoms. Left ventricular systolic dysfunction was found in only one patient. The etiology of complete heart block in these patients probably was an acute viral myocarditis that preferentially affected the conduction system. Two of these eight patients had complete recovery of the atrioventricular conduction. The rest had no improvement or had only partial recovery and subsequently underwent permanent cardiac pacemaker insertion.

Significance of a widened mediastinum in blunt chest trauma patients.

Eighteen blunt chest trauma patients who had mediastinal widening on chest roengenogram were studied for the correlation with traumatic ruptured of the aorta or its major branches. Seventeen patients were male and one was female. The age ranged from 18 to 39 years, mean 26.17+/-6.85SD. The Injury Severity Score (ISS) ranged from 9 to 34, mean 25.5+/-6.49SD. Fourteen patients (77.8%) sustained motorcycle accidents, 3 patients (16.7%) sustained car accidents and 1 patient (5.5%) fell from a 4 storey building. All patients underwent aortography to search for traumatic rupture of the aorta or its major branches. Six patients had computed tomography of the chest before aortography. Nine patients (50%) had normal aortography. The remaining 9 patients who had positive aortography underwent urgent thoracotomies, 8 of them had traumatic rupture of the aorta or its major branches, the remaining 1 patient had normal operative finding. Of the 8 patients who had traumatic rupture of the aorta or its major branches, 1 patient died. The mortality was 12.5 per cent. The rate of traumatic rupture of the aorta or its major branches in patients who had blunt chest trauma and widening of the mediastinum on chest roengenogram in our study was 44.4 per cent. The sensitivity of aortography for diagnosis of traumatic rupture of the aorta or its major branches was 100 per cent and the specificity was 90 per cent. On the basis of this study, we conclude that blunt chest trauma patients with widened mediastinum on chest roengenogram have a significantly high rate of traumatic rupture of the aorta or its major branches. All blunt chest trauma patients who have widened mediastinum on chest reongenogram should undergo further investigations to exclude traumatic rupture of the aorta or its major branches. We recommend aortography as the investigation of choice due to its accuracy and usefulness in management plan.

Transcatheter coil occlusion of patent ductus arteriosus.

Between May 1995 and October 1997, 17 cases of small patent ductus arteriosus (PDA) underwent percutaneous coil occlusion at the Department of Pediatrics, Chulalongkorn Hospital. The mean age was 5.3 +/- 3.6 years (range, 1 year 4 months to 12.0 years); mean weight was 18.9 +/- 11.7 kg (range, 9 to 48 kg). The mean minimum diameter of the PDA was 2.8 +/- 0.6 mm (range, 1.7 to 4.0 mm). PDA occlusion was achieved with one coil in 9 patients and two coils in 8 patients. One patient required the second coil occlusion procedure to occlude the residual PDA leakage. Of the 17 patients, coils were successfully implanted in 15 patients: complete closure of PDA was obtained in 14 patients, confirmed by aortography or by color flow echo imaging or both. In the two unsuccessful coil implantation cases, coils migrated to the distal left pulmonary artery (1 case) and the distal right pulmonary artery (1 case). They could not be retrieved. Both patients had surgical closure of PDA on the following day after the failed procedure. No clinical and chest X-ray showed any evidence of pulmonary complication from the migrated coils up to 1-year follow-up. PDA coil occlusion provides an alternative to surgical closure. The procedure is safe and has a good result.

Successful modified Norwood operation for hypoplastic left heart syndrome in neonatal period: the first reported case in Thailand.

We report a neonatal patient with hypoplastic left heart syndrome on whom Modified Norwood operation was performed when she was 21 days old. The details of the operative technic and postoperative care were presented. Her growth and development at 6 months after operation was in normal range. This is the first successful modified Norwood operation for hypoplastic left heart syndrome in the neonatal period in Thailand.