Pediatric Cardiothoracic CT Guideline Provided by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group: Part 2. Contemporary Clinical Applications

The use of pediatric cardiothoracic CT for congenital heart disease (CHD) was traditionally limited to the morphologic evaluation of the extracardiac thoracic vessels, lungs, and airways. Currently, the applications of CT have increased, owing to technological advancements in hardware and software as well as several dose-reduction measures. In the previously published part 1 of the guideline by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group, we reviewed the prerequisite technical knowledge for clinical applications in a user-friendly and vendor-specific manner. Herein, we present the second part of our guideline on contemporary clinical applications of pediatric cardiothoracic CT for CHD based on the consensus of experts from the Asian Society of Cardiovascular Imaging CHD Study Group. This guideline describes up-to-date clinical applications effectively in a systematic fashion.

Pediatric Cardiothoracic CT Guideline Provided by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group: Part 2. Contemporary Clinical Applications

The use of pediatric cardiothoracic CT for congenital heart disease (CHD) was traditionally limited to the morphologic evaluation of the extracardiac thoracic vessels, lungs, and airways. Currently, the applications of CT have increased, owing to technological advancements in hardware and software as well as several dose-reduction measures. In the previously published part 1 of the guideline by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group, we reviewed the prerequisite technical knowledge for clinical applications in a user-friendly and vendor-specific manner. Herein, we present the second part of our guideline on contemporary clinical applications of pediatric cardiothoracic CT for CHD based on the consensus of experts from the Asian Society of Cardiovascular Imaging CHD Study Group. This guideline describes up-to-date clinical applications effectively in a systematic fashion.

Isolation of the Left Subclavian Artery with Right Aortic Arch in Association with Bilateral Ductus Arteriosus and Ventricular Septal Defect

Right aortic arch with isolation of the left subclavian artery is a rare anomaly. The incidence of bilateral ductus arteriosus is sporadic, and a right aortic arch with isolation of the left subclavian artery in association with bilateral ductus arteriosus is therefore extremely rare. Since the symptoms and signs of isolation of the left subclavian artery can include the absence or underdevelopment of the left arm, subclavian steal syndrome, or pulmonary artery steal syndrome, the proper therapeutic approach is controversial. We report a case in which surgical reconstruction was used to treat isolation of the left subclavian artery with right aortic arch in association with bilateral ductus arteriosus and a ventricular septal defect.

Hybrid Procedure for Pulmonary Atresia with Ventricular Septal Defect in a Low Birth Weight Neonate

Cardiac surgery in neonates with congenital heart disease has progressed dramatically in the past three decades. However, low-birth-weight neonates with congenital heart disease continue to challenge the intellectual and technical skills of healthcare professionals. We present a case of a low-birth-weight neonate with pulmonary atresia and a ventricular septal defect, in whom palliation was achieved with a right ventricular outflow tract stent using a hybrid procedure.

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.

Heart Transplantation in Pediatric Patients: Twelve-Year Experience of the Asan Medical Center

Heart transplantation is a standard treatment for end-stage heart disease. Pediatric heart transplantation, however, is not frequently performed due to the shortage of pediatric heart donors. This is the first report of pediatric heart transplantation in Korea. Our retrospective study included 37 patients younger than 18 yr of age who underwent heart transplantation at Asan Medical Center between August 1997 and April 2009. Preoperative diagnosis was either cardiomyopathy (n = 29, 78.3%) or congenital heart disease (n = 8, 22.7%). Mean follow up period was 56.9 +/- 44.6 months. There were no early death, but 7 late deaths (7/37, 18.9%) due to rejection after 11, 15, 41 months (n = 3), infection after 5, 8, 10 months (n = 3), suspicious ventricular arrhythmia after 50 months (n = 1). There was no significant risk factor for survival. There were 25 rejections (25/37, 67.6%); less than grade II occurred in 17 patients (17/25, 68%) and more than grade II occurred in 8 patients (8/25, 32%). Actuarial 1, 5, and 10 yr survival was 88.6%, 76.8%, and 76.8%. Our midterm survival of pediatric heart transplantation showed excellent results. We hope this result could be an encouraging message to do more pediatric heart transplantation in Korean society.

Long Term Results of Right Ventricular Outflow Tract Reconstruction with Homografts

BACKGROUND: Homograft cardiac valves and valved-conduits have been available in our institute since 1992. We sought to determine the long-term outcome after right ventricular outflow tract (RVOT) reconstruction using homografts, and risk factors for reoperation were analyzed. MATERIALS AND METHODS: We retrospectively reviewed 112 patients who had undergone repair using 116 homografts between 1992 and 2008. Median age and body weight at operation were 31.2 months and 12.2 kg, respectively. The diagnoses were pulmonary atresia or stenosis with ventricular septal defect (n=93), congenital aortic valve diseases (n=15), and truncus arteriosus (N=8). Mean follow-up duration was 79.2+/-14.8 months. RESULTS: There were 10 early and 4 late deaths. Overall survival rate was 89.6%, 88.7%, 86.1% at postoperative 1 year, 5 years and 10 years, respectively. Body weight at operation, cardiopulmonary bypass (CPB) time and aortic cross-clamping (ACC) time were identified as risk factors for death. Forty-three reoperations were performed in thirty-nine patients. Freedom from reoperation was 97.0%, 77.8%, 35.0% at postoperative 1 year, 5 years and 10 years respectively. Small-sized graft was identified as a risk factor for reoperation. CONCLUSION: Although long-term survival after RVOT reconstruction with homografts was excellent, freedom from reoperation was unsatisfactory, especially in patients who had small grafts upon initial repair. Thus, alternative surgical strategies not using small grafts may need to be considered in this subset.

Modified Damus-Kaye-Stansel/Dor Procedure for a Newborn With Severe Left Ventricular Aneurysm

Congenital left ventricular aneurysm (CVA) is a rare cardiac malformation. The prognosis is variable, depending on such factors as the size in comparison to the ventricular cavity, signs of heart failure, arrhythmia and so on. Most infants and young children with large aneurysm showed poor clinical outcomes. Here, we report the case of patient who was prenatally diagnosed with a large CVA, who had severe left ventricular dysfunction at 21 weeks' gestation for which she successfully underwent a modified Damus-Kaye-Stansel/Dor procedure.

Mechanical Circulatory Support to Control Medically Intractable Arrhythmias in Pediatric Patients After Cardiac Surgery

Postoperative intractable arrhythmia can result in high morbidity and mortality. This report describes our experiences using mechanical circulatory support (MCS) to control medically intractable arrhythmias in three pediatric patients with congenital heart disease (CHD), after palliative or total corrective open-heart surgery.

Twelve Years of Experience with Vascular Ring Surgery / 대한흉부외과학회지

BACKGROUND: Vascular ring is a rare anomaly of the aortic arch. We did surgical repair procedures on 16 cases of vascular ring over the past 12 years. This article reviews our results. MATERIAL AND METHOD: Between 1995 and 2007, 16 patients (5 with double aortic arch, 7 with right aortic arch-left ligamentum, 4 with pulmonary artery sling) underwent surgical repair. Mean age at the time of the operation were as follows: double aortic arch, 5.7+/-5.5 years; right aortic arch-left ligamentum, 6.1+/-13.4 years; pulmonary artery sling, 2.9+/-2.6 years. Five patients (71%) with right aortic arch-left ligamentum had an associated Kommerell's diverticulum. Two patients (40%) with double aortic arch, 2 patients (28.6%) with right aortic arch-left ligament and 4 patients (100%) with pulmonary artery sling had associated airway stenosis. Cardiac anomalies were present in 8 of 16 patients. RESULT: There was no peri-operative or post-operative mortality. The mean hospital stay was 27.1+/-38.2 days. None of our patients underwent reoperation. CONCLUSION: Vascular ring is rare, but, it needs surgical correction. It is important to suspect the diagnosis and to validate with echocardiography. Preoperative and postoperative computed tomography and bronchoscopy are useful to evaluate the airway and surrounding structures.

Transplantation of an Extremely Oversized Heart after Prolonged Extracorporeal Membrane Oxygenation Assistance in a 3-month-old / 대한흉부외과학회지

According to the 2007 International Society for Heart and Lung Transplantation (ISHLT) report, a congenital diagnosis, infantile transplantation and being on extracorporeal membrane oxygenation (ECMO) at the time of transplant are risk factors for mortality for the patients who undergo a heart transplant, and a large body weight ratio also increases the risk of mortality. The patient of this case underwent a Ross operation and mitral valve repair due to left ventricle outflow track obstruction and mitral regurgitation. But the baby was treated with ECMO due to heart failure after the operation. When he was 3-months-old and had been on 30 days of ECMO, he underwent a heart transplant with a heart that had a high donor-recipient weight ratio (4.42). We present this case from a technical standpoint and we include a review of the relevant literature.

The Ross Procedure in Pediatric Patients: 10 Years Experience at the Asan Medical Center / 대한흉부외과학회지

BACKGROUND: The Ross procedure is known as a good surgical option for a young age group with aortic valve problems, but few reports on the Ross procedure are available in the Korean literature. This study is a review of our midterm results of 10 year experience with the pediatric Ross operation in Asan Medical Center. MATERIAL AND METHOD: From March 1997 to October 2008, eighteen patients who were aged less than 16 years underwent the Ross procedure. There were 11 males and 7 females. The patients median age was 8.5 years (range: 0.5~14.0). The aortic valve pathophysiology was 6 patients with aortic insufficiency, 4 patients with aortic stenosis, 7 patients with mixed aortic stenoinsufficiencey and 1 patient with infective endocarditis. The valve morphology was bicuspid in 11 and tricuspid in 7. All the patients were operated on with the root replacement technique. All the pumonic valves were replaced with an allograft except for one pericardial monocusp valve. The mean follow up duration was 52.8 months (range: 5.8~138.2 months). We reviewed the echocardiographic data with focusing on the autograft dysfunction and reoperation. RESULT: There was no hospital mortality and late mortality. According to the last echocardiographic data, 2 autografts showed aortic regurgitation grade 2, 4 autografts showed aortic regurgitation grade 1 and the others were less than trivial. Reoperation of the pulmonic position conduit was performed 4 times in three patients. The rate of freedom from reoperation at 5 years was 72.2%. On the serial follow up, the Z-values of the aortic annulus/aortic sinus were changed from 1.6+/-1.7/0.9+/-1.7 at preoperation to 1.8+/-1.6 (p=0.64)/2.2+/- 0.9 (p=0.01) at the last follow-up. There was no significant relation between the growth of the neoaortic root and neoaortic insufficiency. CONCLUSION: Our midterm results of the Ross procedure in pediatric patients showed good autograft function and growth potential. Yet reoperation due to allograft dysfunction was a major concern.

Mid to Long Term Outcomes of Surgical Treatment for Isolated Coarctation of Aorta / 대한흉부외과학회지

BACKGROUND: The surgical repair of an isolated coarctation of the aorta, without complex cardiac anomalies, has improved, with very good results. However, despite the success of surgical repair, many long-term complications, such as hypertension, re-coarctation and an aortic aneurysm, still exist. MATERIAL AND METHOD: Between 1991 and 2006, 50 patients diagnosed with an isolated coarctation of the aorta were reviewed retrospectively. The incidence of re-coarctation and hypertension were compared with respect to age and surgical methods. RESULT: There were no early & late mortality, or post operative aortic aneurysms. Hypertension developed in 11 patients (22%). A greater number of patients in the child/adult group had hypertension (52.4%) than in the neonate/infant group (0%). With respect to the surgical methods, the patients in the graft interposition group suffered more hypertension (88.9%) than those in the EEEA (extended end to end anastomosis) group (5.3%). Post operative re-coarctation developed in 2 out of the 29 patients (6.9%) in the neonate/infant group and 2 out of the 21 patients (9.5%) in the child/adult group, but without any statistical difference. There were no statistical differences between the operative type-related groups. CONCLUSION: Even though the surgical outcomes have greatly improved, an isolated coarctation of the aorta still has many long-term problems, such as hypertension and re-coarctation. An isolated coarctation is accepted as a systemic vascular dysfunction, and often progresses to other cardiovascular diseases. Therefore, patients with a coarctation of the aorta have to be carefully followed-up, and aggressive management must be given when required.

Mitral Valve Repair for Mitral Regurgitation in Pediatric Patients / 대한흉부외과학회지

BACKGROUND: Compared to adult patients, mitral regurgitation in pediatric patients is uncommon and it shows a wide spectrum of morphologic abnormalities. We retrospectively evaluated the midterm results of mitral valve repair in pediatric patients. MATERIAL AND METHOD: Between December 1993 and August 2006, mitral valve repair was performed in 35 patients who were aged less than 18 years. The mean age was 5.3+/-5.3 years and the mean body weight was 20.0+/-16.3 kg. 18 patients had associated cardiac anomalies. The most common pathologic finding was leaflet prolapse (n=17). The most common method of repair was the double orifice technique (n=15). RESULT: There was no early mortality. Eight patients underwent reoperation (24.2%), and five of them required mitral valve replacement. Among the four ring annuloplasty cases, two have developed mitral stenosis. Four out of the 14 double orifice cases required reoperation. One case of early mortality and one case of late mortality occurred in the reoperation cases. The 5-year survival rate and the freedom from reoperation rate were 93.3+/-4.6% and 76.1+/-8.2%, respectively. The 5-year freedom from mitral valve replacement rate was 83.6+/-6.7%. There was no significant risk factor for reoperation. CONCLUSION: The midterm results of mitral valve repair are very acceptable in pediatric patients compared to the adult cases, although the reoperation rate is slightly higher.

Surgical Treatment of Arrhythmias Associated with Congenital Heart Disease / 대한흉부외과학회지

BACKGROUND: We analyzed our experience of arrhythmia surgery in patients with congenital heart disease. MATERIAL AND METHOD: A retrospective review was performed on 43 consecutive patients with congenital heart disease, who underwent arrhythmia surgery between June 1998 and June 2006. RESULT: The median age at surgery was 52 years (4~75 years). The most frequent cardiac anomaly was an atrial septal defect (23/43, 53.5%). The types of arrhythmias were atrial flutter-fibrillation, intermittent non-sustainable ventricular tachycardia and others in 37, 2 and 4, respectively. Arrhythmia surgery consisted of a bi-atrial maze operation in 18 patients (modified cox maze III procedure in 5 patients, and a right side maze plus pulmonary vein cryo-isolation in 13), right side maze operation in 18 patients, cavo-tricuspid isthmus cryoablation for benign atrial flutter in 4 patients, right ventricular endocardial cryoablation in 2 patients and extranodal cryoablation for atrioventricular node re-entry tachycardia in 1 patient. The median follow-up was 23.8 months (1~95.2 months). There was no early mortality, and one late non-cardiac related death. The overall rates of restored sinus rhythm before discharge and 3~6 months after surgery were 79% and 81%, respectively (bi-atrial maze group: 72% and 83%, right-side maze group: 77%, 77%). CONCLUSION: Arrhythmias associated with congenital heart disease can be safely treated surgically with an excellent intermediate-term outcome.

A Case Report of Restrictive Ventricular Septal Defect & Left Ventricular Out Flow Tract Stenosis Caused by Fibrotic Tissue in Tetralogy of Fallot / 대한흉부외과학회지

The VSD in TOF is usually large and unrestrictive with an equal to or greater than that of the aortic annulus. Typically shunting through the VSD is bidirectional or right-to-left component. Restrictive VSD in TOF caused by ingrowing fibrotic tissue is very rare. We report a case of restrictive VSD and LVOTO in TOF caused by ingrowing fibrotic tissue with the review of literature.

Impact of Pulmonary Vascular Compliance on the Duration of Pleural Effusion Duration after Extracardiac Fontan Procedure / 대한흉부외과학회지

BACKGROUND: Preoperative risk analysis for Fontan candidates is still less than optimal in that patients with apparently low risks may have poor surgical outcome; prolonged pleural drainage, protein losing enteropathy, pulmonary thromboembolism and death. We hypothesized that low pulmonary vascular compliance (PVC) is a risk factor for prolonged pleural effusion drainage after the Fontan operation. MATERIAL AND METHOD: A retrospective review of 96 consecutive patients who underwent the Extracardiac Fontan procedures (median age: 3.9 years) was performed. Fontan risk score (FRS) was calculated from 12 categorized preoperative anatomic and physiologic variables. PVC (mm(2)/m(2) . mmHg) was defined as pulmonary artery index (mm(2)/m(2)) divided by total pulmonary resistance (W.U . m(2)) and pulmonary blood flow (L/min/m(2)), based on the electrical circuit analogue of the pulmonary circulation. Chest tube indwelling time was log-transformed (log indwelling time, LIT) to fit normal distribution, and the relationship between preoperative predictors and LIT was analyzed by multiple linear regression. RESULT: 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 hours were correlated with LIT by univariable analyses. By multiple linear regression, PVC (p=0.0018) and CPB (p=0.0024) independently predicted LIT, explaining 21.7% of the variation. The regression equation was LIT=2.74-0.0158 . PVC+0.00658 . CPB. CONCLUSION: Low pulmonary vascular compliance is an important risk factor for prolonged pleural effusion drainage after the extracardiac Fontan procedure.

Left Ventricular Remodeling in Pediatric Orthotopic Size Mismatched Heart Transplantation / 대한흉부외과학회지

Recently, heart transplantation has been accepted as a standard treatment for infant and children with end-stage cardiomyopathy or complex congenital heart disease. Due to the shortage of donors, size-mismatched cardiac transplantation is common. After size-mismatched transplantation, there could be side-effects such as hypertension and hypertensive encephalopathy because of the big-heart. Donor heart is also known to do remodel as time goes by. This is a case report of a size-mismatched heart transplantation between 9-year-old boy and a 39-year-old female whose body weight is almost twice of him. In this case, classical postoperative hypertension and hypertensive encephalopathy developed but was successfully managed. The donor heart has remodeled to normal dimension during 3 years follow-up period.

Postoperative Pulmonary Vein Stenosis (PVS) in Patients with TAPVR / 대한흉부외과학회지

BACKGROUND: Despite recent advances in surgical technique and perioperative care of total anomalous pulmonary venous return (TAPVR), post-repair pulmonary vein stenosis (PVS) remains as a serious complication. We thought that the most important factors of TAPVR repair to prevent PVS were good exposure, proper alignment, and sufficient stoma size. We analyzed our experience retrospectively. MATERIAL AND METHOD: Between Jan. 1995 and Feb. 2005, we studied 74 patients diagnosed with TAPVR suitable for biventricular repair. Supra-cardiac type (n=41, 55.4%) was the most common. Mean CPB time, ACC time, and TCA (40.5%, 30/74) time were 92.1+/-25.9 min, 39.1+/-10.6 min, and 30.2+/-10.7 min, respectively. Mean follow-up duration was 41.4+/-29.1 months and follow-up was possible in all patients. RESULT: The median age and body weight at operation were 28.5 days (0~478 days) and 3.4 kg (1.4~9 kg). Early mortality was 4.1% (3/74). Causes of death were pulmonary hypertensive crisis, sepsis, and sudden death. There was PR-PVS in 2 patients (early: 1, late: 1). Both patients were cardiac type TAPVR drained to coronary sinus. Re-operations were done but only one patient survived. Cumulative survival rate in 5 year and percent freedom from PVS were 94.5+/-2.7% and 97.2+/-2.0%, respectively. CONCLUSION: There was no PVS in patients who underwent extra-cardiac anatomosis between LA and CPVC. Therefore it could be said that our principle might be effective in preventing PR-PVS in patients suitable two-ventricle.

Successful Conversion Arterial Switch Operation after Palliative Senning Operation / 대한흉부외과학회지

Six year-old female having TGA, VSD with severe PHT which was considered inoperable for anatomical correction, received palliative Senning procedure. During follow-up, she was given prostacyclin and at the age of 21, she received Senning takedown, arterial switch and VSD closure after a reevaluation of the hemodynamic status. Significant reduction in PHT was found and she is doing well without complication 3 months after the operation.