The long-term effects of the fenestration in patients with extracardiac Fontan circulation-a multicenter Korean cohort study based on national Fontan registry.

Introduction: The long-term effects of fenestration in patients with Fontan circulation remain unclear. We aim to evaluate the fenestration impact on early and late outcomes in patients with extracardiac Fontan (ECF) using a propensity score matching analysis. Methods: We performed an extensive retrospective multicenter clinical data review of the Korean Fontan registry and included 1,233 patients with surgical ECF (779 fenestrated, 454 non-fenestrated). Demographics, baseline, and follow-up data were collected and comprehensively analyzed. Patients were divided into two groups according to the baseline presence or absence of surgical fenestration. Subsequently, patients were sub-divided according to the fenestration status at the last follow-up. Propensity-score matching was performed to account for collected data between the 2 groups using a multistep approach. The primary outcomes were survival and freedom from Fontan failure (FFF). We also looked at postoperative hemodynamics, cardiopulmonary exercise test results, oxygen saturations, and functional status. Results: After propensity-score matching (454 matched pairs), there was no difference in survival or FFF between the 2 groups. However, ECF patients with baseline fenestration had significantly lower oxygen saturation (p = 0.001) and lower functional status (p < 0.001). Patients with fenestration had significantly longer bypass times, higher postoperative central venous pressure, higher postoperative left atrial pressure, and less prolonged pleural effusion in the early postoperative period. The propensity score matching according to the fenestration status at the last follow-up (148 matched pairs) showed that patients with a persistent fenestration had significantly lower oxygen saturation levels (p < 0.001). However there were no intergroup differences in the functional status, survival and FFF. Conclusions: Our results showed no long-term benefits of the Fenestration in terms of survival and FFF. Patients with persistent fenestration showed oxygen desaturation but no difference in exercise intolerance was shown between the 2 groups.

The compatibility of new blood pressure reference values for Korean children and adolescents with the US reference: the Korean Working Group of Pediatric Hypertension.

BACKGROUND: Childhood hypertension is associated with hypertension and metabolic syndrome in adulthood. Since the definition of childhood hypertension is based on the distribution of normative blood pressure (BP), a reference range is essential to create hypertension guidelines for children. We aimed to investigate the compatibility of the new Korean BP reference with the United States (US) BP reference based on the 2017 Clinical Practice Guideline. METHODS: We compared the new Korean reference BP values for children and adolescents aged 10 to 17 years with those in the 2017 Clinical Practice Guidelines. We also analyzed the differences in the prevalence of hypertension in Korean children and adolescents when reference value was applied. Considering Korean and US BP references together, linear trend lines were sought. RESULTS: Systolic BP (SBP) and diastolic BP (DBP) values in 95th percentiles showed no significant differences between the two BP references. Applying the two reference values, there was no significant difference in the prevalence of elevated BP and a combination of elevated BP and hypertension. Combining the Korean and US BP values and plotting them against age, approximate lines for the 90th and 95th SBP and DBP percentiles were observed. CONCLUSIONS: The BP values of the new Korean BP reference were similar to those of the US BP reference; they were reliable and interchangeable.

Association between the Use of Diuretics and Size Reduction in Pediatric Atrial Septal Defect.

BACKGROUND AND OBJECTIVES: While diuretics are sometimes used in atrial septal defect (ASD) treatment, their effect on ASD size reduction remains unclear. We aimed to evaluate the efficacy of diuretics in ASD size reduction in pediatric patients. METHODS: We retrospectively reviewed the medical records of patients with secundum ASD (size ≥10 mm), between 2005 and 2019. Patients were divided into two groups based on the diuretic administration. RESULTS: Of the 73 enrolled patients, 40 received diuretics. The initial age at ASD diagnosis (2.8±1.7 vs. 2.5±2.0 years, p=0.526) and follow-up duration (22.3±11.4 vs. 18.7±13.2 months, p=0.224) were not significantly different between the groups. The ASD diameter at the initial diagnosis (13.7±2.0 vs. 13.5±3.4 mm, p=0.761) and the indexed ASD diameter (25.5±5.9 vs. 26.9±10.3 mm/m², p=0.493) were also not significantly different between two groups. The ASD diameter significantly increased in the non-diuretic group during follow-up (0.0±2.9 vs. +2.6±2.0 mm, p<0.001). The indexed ASD diameter significantly decreased in the diuretic group during follow-up (-5.7±6.5 vs. +0.2±3.9 mm/m², p<0.001). In the linear mixed model analysis, diuretic use was associated with ASD diameter decrease (p<0.001) and indexed ASD diameter reduction (p<0.001) over time. Device closure was more frequently performed in the diuretic (75.0%) than in the non-diuretic group (39.4%). CONCLUSIONS: Patients receiving diuretics are less likely to undergo surgery. The diuretics administration may be associated with the use of smaller ASD devices for transcatheter treatment through ASD size reduction.

The occurrence of coronary artery lesions in Kawasaki disease based on C-reactive protein levels: a retrospective cohort study.

BACKGROUND: This study aimed to assess the occurrence of coronary artery lesions (CAL) in patients with Kawasaki disease (KD) according to serum C-reactive protein (CRP) levels. METHODS: This retrospective analysis was based on the nationwide survey of KD conducted in the Republic of Korea between 2015 and 2017. We enrolled 9131 patients and defined low (< 3 mg/dL) and high (≥3 mg/dL) CRP groups. Demographic data, clinical characteristics, z-scores, and scores based on the Japanese criteria for CAL were compared between the two groups. Logistic regression analysis was used to identify CAL risk factors. RESULTS: The low CRP group accounted for 23% of patients. The mean age at diagnosis was higher in high CRP group compared to the low CRP group (34.4 ± 24.9 vs 31.7 ± 24.8 months, p < 0.001). Fever duration before treatment was not significantly different between the two groups (5.1 ± 1.7 days vs. 5.2 ± 2.1 days; p = 0.206). A non-response to intravenous immunoglobulin treatment was found in 1377 patients (20.1%) and 225 patients (11.7%) in the high and low CRP groups, respectively (p < 0.001). CAL were found in 12.9 and 18.3% of the high and low CRP patients, respectively (p < 0.001), based on z-scores; and in 9.9 and 12.5%, respectively (p = 0.001), based on the Japanese criteria in the acute phase. The giant coronary artery aneurysm occurrence ratio was similar between groups (p = 1.0). CONCLUSIONS: CAL occurred in patients with both high and low CRP. Therefore, patients with KD should be carefully monitored regardless of their CRP levels.

Early development of hepatic fibrosis after Fontan procedure: A non-invasive study of a subclinical liver disease.

BACKGROUND: To evaluate subclinical liver fibrosis after Fontan procedure using a comprehensive method that reflects the overall liver status rather than the focal biopsy lesion. METHOD: This cross-sectional study included 66 patients without symptoms of liver disease who had at least 5 years of elapsed time since the Fontan procedure (time since Fontan procedure 17.5 ± 7.3 years). Serum enhanced liver fibrosis (ELF) scores and 2D shear wave elastography (SWE), which are expected to detect liver fibrosis earlier than liver enzyme tests and ultrasonography, were evaluated along with general examinations. RESULTS: Liver cirrhosis diagnosed by ultrasonography showed a marked increase 16 years after surgery (elapsed time: 6-15 years since Fontan, 43.8%; 16-25 years, 70.8%; 26-35 years, 90.0%). The age-adjusted ELF score and liver stiffness according to SWE were elevated during the early postoperative period (6-15 years since Fontan). In adulthood (elapsed time > 16 years), the adjusted ELF score was correlated with liver stiffness (r = 0.514, p = .009) and liver enzyme levels. There was no correlation between liver fibrosis and the Fontan palliation type. AST to platelet count ratio and FIB-4, which are non-invasive fibrosis markers, presumed absence of fibrosis in approximately 90% of patients. CONCLUSIONS: In the evaluation of early liver fibrosis after the Fontan procedure, abnormal findings of 2D SWE and ELF scores were observed before abnormal ultrasound and liver enzyme results. Therefore, these indicators may be helpful for the diagnosis of early liver fibrosis, and further longitudinal study might be needed.

Blood Pressure Reference Values for Normal Weight Korean Children and Adolescents: Data from The Korea National Health and Nutrition Examination Survey 1998-2016: The Korean Working Group of Pediatric Hypertension.

BACKGROUND AND OBJECTIVES: Hypertension is becoming one of the most common health conditions in children and adolescents due to increasing childhood obesity. We aimed to provide the auscultatory blood pressure (BP) normative reference values for Korean non-overweight children and adolescents. METHODS: BP measurements in children and adolescents aged 10 to 18 years were performed in the Korean National Health and Nutrition Examination Survey (KNHANES) from 1998 to 2016. BP was measured using a mercury sphygmomanometer. Sex-, age- and height-specific systolic BP (SBP) and diastolic BP (DBP) percentiles were calculated in the non-overweight children (n=10,442). We used the General Additive Model for Location Scale and Shape method to calculate BP percentiles. RESULTS: The 50th, 90th, 95th, and 99th percentiles of SBP and DBP tables and graphs of non-overweight children and adolescents aged 10 to 18 years were presented by age and height percentiles. We found that the SBP and DBP at the 95th percentile were well correlated with height. The BP tables presented by height contained BP values from 124 cm to 190 cm for boys and from 120 cm to 178 cm for girls. Boys had higher SBP and DBP. CONCLUSIONS: We provided the sex-, age- and height-specific auscultatory BP values using the KNHANES big data. These may be useful in diagnosis and treatment of hypertension in Korean children and adolescents.

Eisenmenger Syndrome in Adults: Treatment Pattern and Prognostic Factors in the Advanced Pulmonary Vasodilator Era.

Patients with Eisenmenger syndrome (ES) have a higher mortality rate than patients with simple congenital heart disease (CHD). To determine factors associated with death in the era of advanced pulmonary vasodilator treatment, we analyzed the characteristics of adult ES patients depending on underlying CHD. Simple septal defects and patent ductus arteriosus were classified as simple CHD, and other conditions were classified as complex CHD. Sixty-seven adult ES patients (50.7% women) were reviewed retrospectively. CHD was diagnosed at a median of 10.0 years of age and ES was diagnosed at 18.6 years. Thirteen patients (19.4%) died; the median age was 38.6 years (IQR 32.2-47.8). In a multivariate analysis, patients with SpO2 < 85% had a higher mortality rate than others [hazard ratio (HR) 9.7; 95% confidence interval (CI) 1.002-95.2, p = 0.05]. In simple CHD patients, those with a low platelet count (< 100 × 109/L) or low SpO2 (< 85%) were at a higher risk of death than those without (HR 16.32, 95% CI 1.25-2266.31, p = 0.032; and HR 38.91, 95% CI 3.44-5219.41, p = 0.001, respectively). Advanced pulmonary vasodilators were used more in survivors than in non-survivors (48.1% vs. 15.4%, p = 0.032). Low SpO2 and platelet count were related to mortality in adult ES, especially in those with simple CHD. Therefore, careful attention should be paid to the care of adult ES patients with this tendency; active pulmonary vasodilator treatment should be considered.

Patients diagnosed with long QT syndrome after repair of congenital heart disease.

BACKGROUND: Patients with repaired congenital heart disease (CHD) can have both depolarization and repolarization abnormalities. A coexisting long QT syndrome (LQTS) may cause electrical instability in these patients; however, diagnosing LQTS is difficult owing to intraventricular conduction delay or paced rhythm after the operation. We report on six patients diagnosed with LQTS after CHD repair. METHODS: We investigated two male and four female patients. Clinical data, electrocardiographic findings, and genetic analysis results were reviewed. RESULTS: The range of patient age at LQTS diagnosis was 1.4-22 years. There were two patients with tetralogy of Fallot, four with septal defect, and one with tricuspid atresia. All patients underwent total correction or a staged operation, without events. The diagnosis of LQTS was made in four asymptomatic patients and two symptomatic patients with recurrent syncope and ventricular fibrillation. During the postoperative follow-up, their median QTc interval and QTc dispersion increased (from 474 and 41 ms preoperatively to 541 and 141 ms postoperatively, respectively; P = 0.043). T-wave notching over three leads was observed in three patients. Genetic analysis showed SCN5A mutation in one, KCNH2 mutation in three, KCNQ1 mutation in one, and no identified mutation in one patient. An implantable cardioverter defibrillator was placed in two patients. CONCLUSION: A coexisting LQTS may confer additional risk for arrhythmia and sudden cardiac death in patients with CHD. Suspicion of LQTS and careful monitoring of the QT interval and T-wave morphology are important during the follow-up of patients with repaired CHD.

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.

Impaired Vascular Function of the Aorta in Adolescents with Turner Syndrome.

To investigate intrinsic vascular abnormalities of the ascending aorta before adulthood in Turner syndrome patients (TS), we compared 25 adolescent TS patients (mean age 14.6 ± 3.4 years) and 16 healthy controls from a university hospital. Blood pressure and other vascular indices were evaluated using echocardiography such as aortic strain, stiffness index, distensibility, and pulse wave velocity. Aortic strain (0.1237 vs. 0.1865, respectively; P = 0.003) and aortic distensibility (0.0049 vs. 0.0081, P = 0.002) were significantly lower in the TS group than in the controls. The fractional area change on velocity vector imaging was also lower in TS patients (29.05 vs. 36.19, P = 0.002). These findings were still observed after adjustment for age, body mass index, and systolic blood pressure. The aortic stiffness index was greater in the TS patients than in the control group (6.79 vs. 3.34, P = 0.02). The pulse wave velocity and ascending aorta diameter did not significantly differ between the TS and control groups. Blood pressures were significantly higher in the TS patients than in the controls (systolic, 120.4 vs. 108.4 mmHg, P = 0.001; diastolic 71.5 vs. 61.7 mmHg, P < 0.001). Although the dimensional changes in the aorta were not clearly observed in adolescents with TS, the elastic properties of the aorta were significantly decreased in TS patients as compared to control subjects.

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.

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 Children's 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.

Airway compression in children with congenital heart disease evaluated using computed tomography.

BACKGROUND: Extrinsic airway compression often complicates the course of congenital heart disease (CHD) repair. This study investigated the risk factors and outcome of airway compression evaluated using computed tomography (CT) in CHD patients. METHODS: Of the 2,729 patients who underwent heart surgery for CHD between 1999 and 2007, airway compression was confirmed using CT in 58 (2.1%) patients. The patients were divided into groups according to the underlying CHD, and their medical records and CT scans were reviewed retrospectively. RESULTS: Airway compression was found more frequently in the vascular ring or absent pulmonary valve syndrome (8 of 11) and repaired aortic arch (22 of 213) groups than in the other groups (28 of 2,505) (p < 0.001). Patients with more severe respiratory manifestations showed greater airway compression on CT (p < 0.001) and had a higher rate of additional surgery to relieve airway compression using multivariate analysis (p = 0.005). Airway compression was ameliorated in 13 of 17 patients after surgery for airway compression. Funnel chest deformity worsened after aortic arch repair and was associated with the need for surgical relief of airway compression. Pulmonary overflow disease could be followed up without additional surgery for airway compression. CONCLUSIONS: Early airway compression detection and management may reduce further morbidity, especially after aortic arch repair. The patient's respiratory manifestation and the underlying disease characteristics must be considered when determining the need for additional surgery for airway compression.

Radiofrequency catheter ablation for supraventricular tachycardia: a comparison study of children aged 0-4 and 5-9 years.

BACKGROUND: The safety and effectiveness of radiofrequency catheter ablation (RFCA) for supraventricular tachycardia (SVT) in young children was investigated. METHODS: Ninety-five children who underwent RFCA procedures were stratified according to age (group 1, 0-4 years, n = 24; group 2, 5-9 years, n = 71) and were evaluated retrospectively. RESULTS: Among the 95 patients, atrioventricular reentrant tachycardia was 78.9%, atrioventricular nodal reentrant tachycardia was 10.5%, and ectopic atrial tachycardia was 8.4%. The acute success rate of RFCA was 97.9% and the recurrence rate was 11.6%. RFCA was performed for different main reasons in each group, including drug-resistant tachycardia (37.5% in group 1 vs 7% in group 2; P = 0.001) and symptomatic tachycardia (4.2% in group 1 vs 57.7% in group 2; P < 0.001). There was no significant difference in success rate, recurrence rate, and procedure and fluoroscopy duration between the two groups. The acute success rates did not differ significantly between patients with a single accessory pathway (AP) and those with multiple APs; however, failure or recurrence was more common in the patients with multiple APs (38.5% vs 11.5%; P = 0.01). The multiple APs were found frequently on the right side (P = 0.005). Septal dyskinesia with left ventricular dysfunction in Wolff-Parkinson-White syndrome and tachycardia-induced cardiomyopathy improved after RFCA. CONCLUSIONS: RFCA was found to be effective and safe for SVT in young children.

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 ß-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.

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.

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.