Hyo Soon An

Pulmonary hypertension in preterm infants with bronchopulmonary dysplasia.

Background and Objectives With the increasing survival of preterm infants, pulmonary hypertension (PH) related to bronchopulmonary dysplasia (BPD) has become an important complication. The aim of this study was to investigate the characteristics and outcome of PH in preterm infants with BPD and to identify the risk factors for PH. Subjects and Methods We reviewed the records of 116 preterm infants with BPD cared for at a single tertiary center between 2004 and 2008. Results Twenty-nine (25%) infants had PH >2 months after birth. PH occurred initially at a median age of 65 days (range, 7-232 days). Severe BPD, a birth weight <800 g, long-term ventilator care and oxygen supplementation, a high ventilator setting, infection, and a patent ductus arteriosus (PDA) were related to PH based on univariate analysis (p<0.05). The infants who had longer oxygen supplementation were significantly more likely to have PH (odds ratio, 18.5; 95% confidence interval, 4.1-84.6; p<0.001). PH was improved in 76% of infants after a median of 85 days (range, 20-765 days). Four infants (14%) died. The death of 3 infants was attributed to PH. Conclusion BPD was frequently complicated by PH. Although PH resolved in the majority of infants, PH in preterm infants with BPD can be fatal. Regular screening for PH and adequate management are required.

Long-Term Outcomes of Pulmonary Hypertension in Preterm Infants with Bronchopulmonary Dysplasia

Background: The long-term cardiovascular outcomes of pulmonary hypertension (PH) in preterm infants with bronchopulmonary dysplasia (BPD) are uncertain. Objectives: The purpose of this study was to assess outcomes of PH in prematurely born children diagnosed with moderate to severe BPD. Methods: We retrospectively reviewed the medical records of patients born before 32 weeks of gestation and diagnosed with moderate to severe BPD from June 2004 to April 2008. Patients were recruited for a cross-sectional study from August to October 2014 and underwent echocardiography. Results: Forty-two children were enrolled. Their mean gestational age and birth weight were 26.2 ± 1.7 weeks and 753.1 ± 172.5 g, respectively. Sixteen patients (38%) were diagnosed with PH at a mean age of 3.3 ± 1.6 months, and the PH improved after a median of 12.3 months (range 0.7-46.6). Cardiovascular function was reassessed at a mean age of 7.7 ± 0.9 years, at which time 1 patient was taking a medication for recurrent PH, and 12 (28.6%) patients exhibited elevated blood pressure. Conventional 2-dimensional and Doppler echocardiography indicated normal ventricular function in all children. However, right ventricular longitudinal strains were decreased in children with previous PH. Conclusions: Subclinical ventricular dysfunction was detectable using sensitive echocardiographic techniques in children with previous BPD-associated PH. Long-term follow-up and meticulous cardiovascular function assessment are required in this population.

Radiofrequency Catheter Ablation for Supraventricular Tachycardia: A Comparison Study of Children Aged 0–4 and 5–9 Years

The safety and effectiveness of radiofrequency catheter ablation (RFCA) for supraventricular tachycardia (SVT) in young children was investigated.

Sudden Cardiac Arrest during Anesthesia in a 30-Month-Old Boy with Syndactyly: A Case of Genetically Proven Timothy Syndrome

Timothy syndrome, long QT syndrome type 8, is highly malignant with ventricular tachyarrhythmia. A 30-month-old boy had sudden cardiac arrest during anesthesia induction before plastic surgery for bilateral cutaneous syndactyly. After successful resuscitation, prolonged QT interval (QTc, 0.58-0.60 sec) and T-wave alternans were found in his electrocardiogram. Starting β-blocker to prevent further tachycardia and collapse event, then there were no more arrhythmic events. The genes KCNQ1, KCNH2, KCNE1 and 2, and SCN5A were negative for long QT syndrome. The mutation p.Gly406Arg was confirmed in CACNA1C, which maintains L-type calcium channel depolarization in the heart and other systems.

Long-Term Prognosis for Patients with Kawasaki Disease Complicated by Large Coronary Aneurysm (diameter ≥6 mm)

Background and Objectives Some patients with Kawasaki disease (KD) develop large coronary aneurysms and subsequent coronary stenosis or obstruction, leading to ischemic heart disease. This study examined the long-term outcomes of patients with KD complicated by large coronary aneurysms. Subjects and Methods The medical records of 71 patients (53 men and 18 women) diagnosed with large coronary aneurysms (diameter ≥6 mm) between December 1986 and December 2013 were retrospectively reviewed from our institutional database. Results The mean age at onset was 4.6±3.3 years, and the mean follow-up duration was 12.5±6.9 years. Maximum coronary artery internal diameter ranged from 6.1 to 25 mm. Giant coronary aneurysms occurred in 48 patients and coronary aneurysms 6-8 mm in diameter developed in 23 patients. Coronary stenosis and/or complete occlusion occurred in 30 patients (42.3%). Catheter and/or surgical interventions (mean: 1.5 interventions, range: 1-5 interventions) were performed in 20 patients (28.2%), 9 months to 18 years after KD onset, resulting in 33.7% cumulative coronary intervention rates at 20 years after onset. There were no differences in cumulative coronary intervention rates between two coronary aneurysm groups (6-8 mm vs. ≥8 mm). Myocardial infarction occurred in 7 patients with a giant aneurysm and there was one death. Conclusions Long-term survival of patients with KD complicated by large coronary aneurysm was good even though 28.2% of patients underwent multiple catheter or surgical interventions. Careful follow-up is also necessary in KD patients with coronary aneurysms 6-8 mm in diameter, such as those with giant aneurysms.

Complications of Cardiac Catheterization in Structural Heart Disease

Background and Objectives Cardiac catheterization is used to diagnose structural heart disease (SHD) and perform transcatheter treatment. This study aimed to evaluate complications of cardiac catheterization and the associated risk factors in a tertiary center over 10 years. Subjects and Methods Total 2071 cardiac catheterizations performed at the Seoul National University Childrens Hospital from January 2004 to December 2013 were included in this retrospective study. Results The overall complication, severe complication, and mortality rates were 16.2%, 1.15%, and 0.19%, respectively. The factors that significantly increased the risk of overall and severe complications were anticoagulant use before procedure (odds ratio [OR] 1.83, p=0.012 and OR 6.45, p<0.001, respectively), prothrombin time (OR 2.30, p<0.001 and OR 5.99, p<0.001, respectively), general anesthesia use during procedure (OR 1.84, p=0.014 and OR 5.31, p=0.015, respectively), and total procedure time (OR 1.01, p<0.001 and OR 1.02, p<0.001, respectively). Low body weight (OR 0.99, p=0.003), severe SHD (OR 1.37, p=0.012), repetitive procedures (OR 1.7, p=0.009), and total fluoroscopy time (OR 1.01, p=0.005) significantly increased the overall complication risk. High activated partial thromboplastin time (OR 1.04, p=0.001), intensive care unit admission state (OR 14.03, p<0.001), and concomitant electrophysiological study during procedure (OR 3.41, p=0.016) significantly increased severe complication risk. Conclusion Currently, the use of cardiac catheterization in SHD is increasing and becoming more complex; this could cause complications despite the preventive efforts. Careful patient selection for therapeutic catheterization and improved technique and management during the peri-procedural period are required to reduce complications.

A Case of Pulmonary Thromboembolism Associated With Hypereosinophilia in a Child

Pulmonary thromboembolism is a very rare event in children, but the mortality rate is reported to be approximately 10%. The majority of children with thromboemboli have multiple risk factors, such as a catheter-related thrombosis, an infection, and a congenital prothrombotic disorder. Hypereosinophilia is very rarely associated with pulmonary emboli in adults; however, this condition has not been reported in children. We present a 12-year-old boy who had a pulmonary thromboembolism and deep vein thrombosis associated with hypereosinophilia and thrombocytopenia. The thromboembolism was managed with anticoagulant therapy and the hypereosinophilia resolved spontaneously.