Jae-n Ko

Analyses of Left Ventricular Myocardial Deformation by Speckle-Tracking Imaging During the Acute Phase of Kawasaki Disease

This study aimed to investigate left ventricular myocardial deformation in children with Kawasaki disease during the acute phase of their illness. A total of 50 patients and 35 normal control subjects were assessed. Data were obtained from the patients during the acute and convalescent phases of Kawasaki disease. Analyses of myocardial deformation [strain (ε), strain rate (SR)] was performed using two-dimensional speckle-tracking imaging in three directions (longitudinal, circumferential, and radial) at the basal and mid levels of the left ventricular myocardium. Basal longitudinal ε (Pxa0<xa00.001) and midlongitudinal ε (Pxa0<xa00.0001) were lower during the acute phase of the disease than in the control subjects and associated with serum albumin level and left ventricular mass index (LVMI). Midlongitudinal SR (Pxa0<xa00.0001) was lower during the acute phase of Kawasaki disease than in the control subjects and associated with LVMI. Decreased systolic SR was not detected in any direction. In conclusion, left ventricular longitudinal systolic ε was significantly decreased during the acute phase of Kawasaki disease. This may be a result of myocardial swelling from myocarditis during the acute phase of the disease.

Outcome of Neonates with Ebstein's Anomaly in the Current Era

Ebstein’s anomaly is frequently detected before birth, with prenatal detection accounting for the majority of cases in the current population. This study aimed to identify the outcome variables among these infants. The medical records of 59 patients with neonatal Ebstein’s anomaly managed at the Asan Medical Center between January, 2001 and June, 2012 were investigated retrospectively. In 46 cases, the diagnosis was made prenatally. Surgical/interventional procedures were performed for 27 of the analyzed patients. Biventricular repair was successful for 12 patients but not for 9 patients with pulmonary atresia. The median follow-up period was 1.96xa0years (range 0.0–10.4xa0years). The overall mortality rate was 23.7xa0% (14/59). Of the 14 deaths, 5 occurred within several hours after birth. The 1- and 5-year survival rates were 78.6 and 76.3xa0%, respectively. Univariate analysis identified several variables related to the time to death: fetal distress (pxa0=xa00.002), prematurity (pxa0=xa00.036), low birth weight (pxa0=xa00.003), diameter of the atrial septal defect (pxa0=xa00.022), and pulmonary stenosis/atresia (pxa0=xa00.001). Neither the Carpentier classification (pxa0=xa00.175) nor the Celermajer index (pxa0=xa00.958) was a significant variable. According to the multivariate analysis, fetal distress (pxa0=xa00.004) and pulmonary atresia/stenosis (pxa0<xa00.001) were significant determinants of outcome. In conclusion, fetal distress and pulmonary atresia/stenosis are significant predictors of mortality in the current population of patients with neonatal Ebstein’s anomaly. A close cooperation of associated clinicians is required for an improvement in outcome. To establish a better surgical strategy for patients with Ebstein’s anomaly and pulmonary atresia, studies of larger populations are required.

Pulmonary vascular compliance and pleural effusion duration after the Fontan procedure

BACKGROUNDnPreoperative risk analysis for Fontan candidates is still less than optimal in that patients with apparently low risks may have a poor outcome, such as prolonged pleural drainage, protein-losing enteropathy, pulmonary thromboembolism and death. We hypothesized that low pulmonary vascular compliance (PVC) is a risk factor for persistent pleural effusion after the Fontan operation.nnnMETHODSnA retrospective review of 85 patients who underwent the extracardiac Fontan procedures (median age: 3.87 years) was performed. Fontan risk score (FRS) was calculated from 12 categorized preoperative anatomical and physiological variables. PVC (mm(2)/m(2) x mmHg) was defined as pulmonary artery index (mm(2)/m(2)) divided by total pulmonary resistance (Wood Unit x m(2)) and pulmonary blood flow (L/min/m(2)), based on the electrical circuit analogy of the pulmonary circulation. Chest tube indwelling time was log-transformed (log indwelling time, LIT) to fit normal distribution, and the relationship between perioperative predictors and LIT was analyzed by multiple linear regression.nnnRESULTSnPreoperative PVC, chest tube indwelling time and LIT ranged from 6 to 94.8 mm(2)/mmHg/m(2) (median: 24.8), 3 to 268 days (median: 20 days), and 1.1 to 5.6 (mean: 2.9, standard deviation: 0.8), respectively. FRS, PVC, cardiopulmonary bypass time (CPB) and central venous pressure at postoperative 12 h were correlated with LIT by univariable analyses. By multiple linear regression, PVC (p=0.002) and CPB (p=0.003) independently predicted LIT, explaining 22% of the variation. The regression equation was LIT=2.744-0.016 PVC+0.007 CPB.nnnCONCLUSIONnLow pulmonary vascular compliance is an important risk factor for prolonged pleural effusion drainage after the extracardiac Fontan procedure.

Tetralogy of Fallot without the infundibular septum–restricted growth of the pulmonary valve annulus after annulus preservation may render the right ventricular outflow tract obstructive

OBJECTIVEnTetralogy of Fallot (ToF) with infundibular septal deficiency (ISD) is commonly associated with postoperative right ventricular outflow tract obstruction (RVOTO), presumably caused by subpulmonary extension of ventricular septal defect (VSD) and restricted growth of the pulmonary valve annulus (PVA). We sought to determine the postoperative growth of the PVA after annulus preservation according to the presence or absence of the infundibular septum.nnnMETHODSnA retrospective review of 90 patients who underwent surgical repair of ToF between June 1997 and August 2008 was performed. Median age at operation was 9.5 months. Infundibular septum was absent in 15 (15/90, 17%). PVA was preserved in 71 patients (71/90, 79%), including 13 patients with ISD (13/15, 87%).nnnRESULTSnMedian follow-up duration was 39 months (2 months to 13 years). There was no early mortality and one late noncardiac death. Among the patients with PVA preservation, reoperation for RVOTO was performed in 4 patients (4/71, 6%), including 3 patients without the infundibular septum. ISD was identified as the only risk factor in reoperation for RVOTO after PVA preservation (RR: 21.85, P = .007). Among the patients who underwent repair with PVA preservation during infancy (n = 43), PVA (Z-score) increased postoperatively in patients with the infundibular septum (+ 0.021/month, P = .009), whereas the changes in PVA (Z-score) were nonsignificant in patients with ISD (-0.021/month, P = .306), with a marginal intergroup difference (P = .056).nnnCONCLUSIONSnPVA preservation in ToF with ISD may be associated with a higher risk for postoperative RVOTO, which can be attributed to the restricted growth of the PVA.

Effectiveness and safety of percutaneous transcatheter implantation of pulmonary arterial stent in congenital heart disease.

Background and Objectives Pulmonary arterial stenosis is a relatively common complication after corrective operation of congenital heart disease. Unilateral stenosis of pulmonary arteries could result in decrease perfusion of affected lung, pulmonary regurgitation, or elevation of right ventricular pressure. Eventually there are increasing risks of right ventricular failure, arrhythmia, or sudden death. However we have limited data of pulmonary arterial stent in paediatric population as the treatment of branch pulmonary stenosis. This study aimed at validating the effectiveness and investigating complications of pulmonary arterial stent implantation in a single institution during mid-term follow up period. Subjects and Methods A total of 42 patients (50 stents) were implanted for treating branch pulmonary arterial stenosis. We used cardiac catheterization for comparing diameter after stent implantation directly and lung perfusion scan indirectly. We also investigated any adverse effect relating the procedure. Results Percent stenosis of stenotic lesions were decreased from 54.1±10.7% to 22.8±12.5% (p<0.001) and degree of decrement in affected lung perfusion was declined from 22.7±8.0% to 10.3±9.0% (p<0.001) immediately and lasts during mid-term follow up period. Complication rate relating the procedure was 12% (6 out of 12) and there was no mortality case. Conclusion This series showed immediate and short term effectiveness of pulmonary arterial stent in congenital heart defects. We concluded that percutaneous transcatheter implantation of pulmonary arterial stent was safe and effective during short and mid-term follow up period.

One and a Half Ventricle Repair in Adults: Postoperative Hemodynamic Assessment Using Phase-Contrast Magnetic Resonance Imaging

BACKGROUNDnOne and a half ventricle repair (1½ repair) strategy has been used for patients with a hypoplastic or dysfunctional right ventricle (RV), or both. We sought to assess the postoperative hemodynamics of 1½ repair using phase-contrast magnetic resonance imaging (PC-MRI).nnnMETHODSnTen adults, 9 with Ebsteins anomaly and 1 with tricuspid stenosis, underwent 1½ repair (median age at operation, 42.4 years). The azygos vein was left open in all patients on 1½ repair to prevent severe postoperative central venous hypertension. Postoperative PC-MRI studies were performed to measure blood flow to the ascending aorta (QAsc-Ao), the main pulmonary artery (QMPA), the superior vena cava (SVC) (QSVC), and the branch pulmonary arteries and veins. From these values, blood flow to the upper compartment of the body (QUC), right ventricular volume unloading effect (QMPA/QAsc-Ao), proportion of blood flow to the upper compartment of the body (QUC/QAsc-Ao), and venous return to arterial forward flow ratio of the upper compartment of the body (QSVC/QUC) were calculated. Two patients also underwent preoperative PC-MRI.nnnRESULTSnOn PC-MRI, QMPA/QAsc-Ao, QUC/QAsc-Ao, and QSVC/QUC were 0.58 to 0.84 (median, 0.67), 0.19 to 0.36 (median, 0.27), and 0.47 to 1.57 (median, 0.93, lower than 1.0 in 7 patients), respectively. In 2 patients who had preoperative and postoperative PC-MRI, QUC/QAsc-Ao decreased from 0.26, 0.32 to 0.21, 0.28, respectively.nnnCONCLUSIONSnAfter 1½ repair, right ventricular volume unloading was effective in all patients, but intercaval collateral veins (ie. QSVC/QUC<1) appeared to develop in most of the patients. Furthermore blood flow to the upper compartment of the body appeared to diminish, presumably due to postoperative elevation of central venous pressure.

Repair of tetralogy of Fallot after the regression of multiple rhabdomyomas in a patient with tuberous sclerosis

CLINICAL SUMMARY A male infant was born at 37 weeks’ gestation and 2380 g birth weight. TOF and multiple cardiac tumors had been diagnosed on fetal echocardiography. Postnatal echocardiography confirmed the prenatal diagnosis: overriding of the aorta, small pulmonary valvular annulus, severe infundibular and valvular pulmonary stenosis, perimembranous ventricular septal defect, smallish branch pulmonary arteries, sizable patent foramen ovale with left-to-right shunt, and multiple echogenic cardiac masses. The largest tumor (22 3 29 mm) from the interventricular septum occupied almost entire left ventricular (LV) cavity (Figure 1, A), but LV inflow and outflow obstruction could not be assessed accurately. Smaller cardiac masses were located at the tricuspid valve, interatrial septum, and LV free wall. Well-known association of multiple cardiac masses with tuberous sclerosis prompted us to conduct brain magnetic resonance imaging and abdominal ultrasonography, which revealed the pathognomonic features of tuberous sclerosis: multiple cortical tubers, subependymal nodules and retinal hamartoma on brain magnetic resonance imaging (Figure 2), and multiple cysts in both kidneys on abdominal ultrasonography. Deletion of exon 10–46 of TSC2 gene mutation was also detected by a genetic test. Because the branch pulmonary arteries were small (McGoon ratio 1.1) and the patient showed progressive cyanosis from severe infundibular stenosis, a right modified Blalock–Taussig shunt with a 3.5 mm-polytetrafluoroethylene vascular graft was placed on postnatal day 15.

Factors associated with reduction of left ventricular mass in children on peritoneal dialysis: LVMI reduction in children on PD

This study aimed to investigate sensitive factors involved in left ventricular mass reduction in children with end‐stage renal disease (ESRD) undergoing peritoneal dialysis.

PS 14-25 B-TYPE NATRIURETIC PEPTIDE IS A GOOD BIOMARKER FOR THE TREATMENT OF HYPERTENSION IN CHILDREN WITH END-STAGE RENAL DISEASE ON PERITONEAL DIALYSIS

Objective: To evaluate the usefulness of serum B-type natriuretic peptide (BNP) level as a clinical biomarker of fluid retention and a target to control body weight for the treatment of hypertension in children on peritoneal dialysis. Design and Method: We included 59 hypertensive patients with end-stage renal disease on peritoneal dialysis who were below 19 years old and have visited Asan Medical Center between February 2005 and February 2016 in this study. We reviewed the changes of body weight (BWt), blood pressure (BP) and serum BNP level between before and after the treatment of hypertension. Data were presented as meanu200a±u200astandard deviation (median, minimum ∼ maximum). Paired t-test was used to evaluate the changes in BWt, BP and BNP. Linear regression analysis was applied for the correlation between the changes of BNP and BP. Results: We evaluated 56 hypertensive events in 30 patients. Initial findings were as follows: BWt 30.5u200a±u200a22.4 (26.5, 3.0 ∼ 93.5) kg, systolic BP (SBP) 153.3u200a±u200a21.5 (150, 110∼241)u200ammHg, diastolic BP (DBP) 100.1u200a±u200a22.3, (99.5, 49 ∼ 181)u200ammHg, BNP 3579.3u200a±u200a6328.9 (1198.5, 305.0 ∼ 22028.0)u200apg/mL. Follow-up results were as follows: BWt 29.1u200a±u200a21.3 (25.0, 3.12 ∼ 86)u200akg, SBP 116.4u200a±u200a17.8 (117.5, 82 ∼ 150)u200ammHg, DBP 73.3u200a±u200a14.2 (75.0, 42.0 ∼ 101.0)u200ammHg, BNP 63.5u200a±u200a49.2 (60.5, 2.0 ∼ 261.))u200apg/mL. SBP (−23.1u200a±u200a13.8, −22.8, −46.9 ∼ 22.5%, Pu200a<u200a0.001), DBP (−24.1u200a±u200a19.2, −24.7, −55.6 ∼ 23.2%, Pu200a<u200a0.001) and BNP (−93.5u200a±u200a8.1, −96.7, −99.9 ∼ −61.0%, Pu200a<u200a0.001) dropped significantly after reduction of BWt (−4.8u200a±u200a4.7, −4.8, −18.7 ∼ 5.6%, Pu200a<u200a0.001). The amount of changes in BNP were significantly correlated with changes in SBP (adjusted R squareu200a=u200a0.221, Pu200a<u200a0.001) and DBP (adjusted R squareu200a=u200a0.203, Pu200a<u200a0.001). Conclusions: We should measure serum BNP in hypertensive patients on peritoneal dialysis and reduce body weight until serum BNP level becomes less than 200 pg/mL if possible.

OS 24-06 HIGH B-TYPE NATRIURETIC PEPTIDE IS ASSOCIATED WITH LEFT VENTRICULAR HYPERTROPHY AND HEART FAILURE IN CHILDREN WITH HYPERTENSION ON PERITONEAL DIALYSIS.

Objective: To evaluate the relationship between B-type natriuretic peptide (BNP) and cardiac parameters on echocardiography. Design and Method: Echocardiography was checked at 6 months ∼ 1 year interval in children with end-stage renal disease on peritoneal dialysis, which was more frequently done in patients with hypertension or any heart problems. We reviewed blood pressure (BP) and echocardiographic findings of those children (since February 2005). Data were presented as meanu200a±u200astandard deviation (median, minimum ∼ maximum). Linear regression analysis was used to see the correlation of BNP with BP. Nonlinear regression analysis power model was used to evaluate the association between serum BNP level and cardiac parameters on echocardiography. Results: Fifty nine patients were enrolled in this study and total of 171 echocardiographic findings were evaluated in association with serum BNP level. Systolic BP (SBP) was 125.3u200a±u200a21.9 (125.0, 56 ∼ 208) mmHg and diastolic BP (DBP) 50.5u200a±u200a16.5 (80.0, 25 ∼ 141) mmHg. Serum BNP level was 938.0u200a±u200a4030.4 (63, 2 ∼ 40897) pg/mL. On echocardiography, left ventricular mass index (LVMI) was 67.3u200a±u200a37.2 (59.8, 12.4 ∼ 332.5) g/m2.7, ejection fraction (EF) 60.6u200a±u200a15.5 (65.4, 13.3 ∼ 90.2) % and fractional shortening (FS) 33.8u200a±u200a11.5 (35.5, 6.0 ∼ 99.3) %. BNP was significantly correlated with SBP (adjusted R squareu200a=u200a0.038, pu200a=u200a0.007), DBP (adjusted R squareu200a=u200a0.024, pu200a=u200a0.026), LVMI (adjusted R squareu200a=u200a0.123, pu200a<u200a0.001), EF (adjusted R squareu200a=u200a0.094, pu200a<u200a0.001) and FS (adjusted R squareu200a=u200a0.069, pu200a<u200a0.001). Other parameters also showed significant correlation with serum BNP level such as internal diameter of left atrium, aorta, right ventricle in diastolic phase and internal diameter of left ventricle in systolic phase etc. Conclusions: Routine measurement of serum BNP is recommended in children on peritoneal dialysis to evaluate the risk of left ventricular hypertrophy and heart failure.