Young-Hwue Kim

Pulmonary vascular compliance and pleural effusion duration after the Fontan procedure

BACKGROUND Preoperative 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. METHODS A 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. RESULTS Preoperative 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. CONCLUSION Low pulmonary vascular compliance is an important risk factor for prolonged pleural effusion drainage after the extracardiac Fontan procedure.

Hybrid palliation for right atrial isomerism associated with obstructive total anomalous pulmonary venous drainage

A twenty-four-day-old girl, who was prematurely born at 36 weeks of gestation, and weighed 2.2 kg, and diagnosed with right atrial isomerism, functionally single ventricle, bilateral superior vena cava (SVC) and obstructive supracardiac total anomalous pulmonary venous drainage (TAPVD) draining to the junction between the right SVC and the right atrium, underwent a hybrid procedure in the operating room, which consisted of pulmonary artery banding, ductus ligation and stenting of the draining vein of TAPVD. Obstruction at the drainage site of TAPVD was initially relieved after stenting, but, one month after the procedure, the distal end of the stent became stenotic and she received bilateral sutureless repair of TAPVD. At postoperative seven months, she underwent bidirectional cavopulmonary shunt uneventfully, and she has been followed-up for two months in a stable state without any problem in the pulmonary venous pathway.

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

OBJECTIVE Tetralogy 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. METHODS A 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%). RESULTS Median 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). CONCLUSIONS PVA 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.

Tracheal Compression by Elongated Aortic Arch in Patients with Congenitally Corrected Transposition of the Great Arteries

We investigate the tracheal compression by aortic arch in patients with congenitally corrected transposition of the great arteries. Fourteen patients whose ascending aorta was connected to descending aorta on the contralateral side were divided into two groups according to the severity of tracheal compression on lateral angiogram: group 1 (stenosis ? 50%, eight patients) and group 2 (stenosis < 50%, six patients). We compared the following variables between the groups: aortic size, lateral displacement of ascending aorta, retrosternal space, and contour of aortic arch. Spiral computed tomography (CT) was done in five patients of group 1. The ratio between measured and normal diameters of ascending aorta of group 1 was significantly larger than that of group 2 (1.57 ± 0.14 compared to 1.19 ± 0.26, p = 0.014). There was linear correlation between the tracheal compression and aortic size (r = 0.69, p = 0.001). The ascending aorta was positioned more laterally and the aortic arch was located more posteriorly in group 1. In four patients with decreased tracheal compression after surgery, aortic size decreased and the ascending aorta restored its anterior position. Spiral CT showed transversely oriented aortic arch and severe tracheal compression in the anteroposterior direction by aortic arch. The tracheal compression by aortic arch in corrected transposition is common when the descending aorta is located on the contralateral side of the ascending aorta. Aortic size, posterior position, elongation, and end-on appearance of the aortic arch are the useful predictors of tracheal compression.

Retrospective Multicenter Study of Respiratory Syncytial Virus Prophylaxis in Korean Children with Congenital Heart Diseases

Background and Objectives We conducted a review of current data on respiratory syncytial virus (RSV) prophylaxis with palivizumab, in Korean children with congenital heart diseases (CHD). In 2009, the Korean guideline for RSV prophylaxis had established up to five shots monthly per RSV season, only for children <1 year of age with hemodynamic significance CHD (HS-CHD). Subjects and Methods During the RSV seasons in 2009-2015, we performed a retrospective review of data for 466 infants with CHD, examined at six centers in Korea. Results Infants received an average of 3.7±1.9 (range, 1-10) injections during the RSV season. Fifty-seven HS-CHD patients (12.2%) were hospitalized with breakthrough RSV bronchiolitis, with a recurrence in three patients, one year after the initial check-up. Among patients with simple CHD, only five (1.1%) patients received one additional dose postoperatively, as per the limitations set by the Korean guideline. Among the 30 deaths (6.4%), five (1.1%) were attributed to RSV infection; three to simple CHD, one to Tetralogy of Fallot, and one to hypertrophic cardiomyopathy (HCM). Of the three HCM patients that exceeded guidelines for RSV prophylaxis, two (66.6%) were hospitalized, and one died of RSV infection (33.3%). Conclusion In accordance to the Korean guideline, minimal injections of palivizumab were administered to patients having HS-CHD <one year of age during the RSV season; the risk of RSV infection remains significant among children with simple CHD, cardiomyopathy, and children above the age of one year with HS-CHD.

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.

Lecompte operation: is it still a viable option for truncus arteriosus?

TECHNIQUE Under moderate hypothermic cardiopulmonary bypass, the truncal artery and both pulmonary arteries were dissected extensively, and the pulmonary arteries were occluded with snares. The truncal artery was crossclamped and blood cardioplegic solution was delivered antegradely. A vertical incision was made on the anterior wall of the right ventricle, and the ventricular septal defect was closed with a Dacron patch through this incision (Figure E2, A). The truncal artery was transected at the level of the upper margin of the pulmonary arterial origin, and a cylindrical segment incorporating the pulmonary trunk was cut off the truncal artery with direct vision of the sinotubular junction of the truncal artery (Figure 1, A). After the Lecompte maneuver, the divided ends of the truncal artery were reanastomosed and the crossclamp was released (Figure 1, B). Under beating heart conditions, the cylindrical segment of the truncal artery was cut in the middle, and truncal artery tissue flaps were used to form the posterior wall of the neopulmonary artery (Figure 2, A). The neopulmonary artery was then approximated and secured to the superior margin of the right ventriculotomy (Figure 2, B), and a pulmonary allograft monocusp patch was used for anterior augmentation of the right ventricular outflow tract (Figure E2, B).