Jae Young Choi

Clinical Characteristics and Prognostic Factors of Primary Pulmonary Vein Stenosis or Atresia in Children

BACKGROUNDnPrimary pulmonary vein stenosis or atresia (PVS/A) is a rare entity with a high mortality rate. The aim of this study was to elucidate the clinical characteristics, progression, and prognostic factors of primary PVS/A in children.nnnMETHODSnWe reviewed the medical records of patients who had primary PVS/A with normally connected pulmonary veins (PVs) at five pediatric cardiology centers in Korea between 1995 and 2010.nnnRESULTSnA total of 34 cases were identified. The median age at diagnosis was 12.0 months. During the follow-up period (median, 18 months; range, 2 to 185 months), PVS/A progressed to previously uninvolved veins in 9 patients. Surgical interventions were performed on 29 patients (venoplasty on 25 and pneumonectomy on 4). Nineteen of the patients who underwent venoplasty had restenosis after a median of 2 months. The sutureless technique did not reduce the rate of restenosis, progression of the disease to previously uninvolved PVs, or mortality rate. The mortality rate was 46.7%, the median age of death was 10.8 months, and the median interval between diagnosis and death was 3.0 months. In univariate analysis, predictors of death included involvement of at least three PVs, bilateral PV involvement, infancy-onset PVS/A, restenosis after surgery, and progression to previously uninvolved PVs. In multivariate analysis, significant risk factors for death were involvement of at least three PVs (hazard ratio, 8.8; p < 0.0001) and progression to uninvolved PVs (hazard ratio, 4.2; p = 0.014).nnnCONCLUSIONSnPrimary PVS/A may carry a significant risk of recurrent and progressive PV obstruction or death even after surgical venoplasty.

Transcatheter closure of perimembranous ventricular septal defect using Amplatzer ductal occluder.

To show that transcatheter closure of perimembranous ventricular septal defect (PMVSD) with the Amplatzer ductal occluder (ADO, AGA Medical Corp, Plymouth, Minnesota) is a safe and effective treatment option.

Clinical outcome of transcatheter closure of patent ductus arteriosus in small children weighing 10 kg or less

Purpose Transcatheter closure has become an effective therapy in most patients with patent ductus arteriosus (PDA). However, there are difficulties in transcatheter closure of PDA in small children. We reviewed clinical outcomes of transcatheter closure of PDA in children weighing less than 10 kg in a single center. Methods Between January 2003 and December 2009, 314 patients with PDA underwent transcatheter closure in our institute. Among them, 115 weighed less than 10 kg. All of these patients underwent transcatheter closure of PDA using either COOK Detachable Coil®, PFM Nit-Occlud®, or Amplatzer duct occluder®. A retrospective review of the treatment results and complications was performed. Results The mean age of patients was 9.1±5.9 months (median, 8 months), and mean weight was 7.6±1.8 kg (median, 7.8 kg). The mean diameter of PDA was 3.2±1.4 mm (median, 3 mm). Complete occlusion occurred in 113 patients (98%). One patient was sent to surgery because of a failed attempt at device closure, and another patient had a small residual shunt after device placement. The average mean length of hospital stay was 3.0±3.3 days, and mean follow-up duration was 21.0±19.6 months. There were no major complications in any of the patients. Conclusion Transcatheter closure of PDA is considered safe and efficacious in infants weighing less than 10 kg. With sufficient experience and further effort, transcatheter closure of PDA can be accepted as the gold standard of treatment for this group of patients.

Transcatheter Closure of Atrial Septal Defect: Does Age Matter?

Atrial septal defect (ASD) is the most common type of common congenital heart disease (CHD) in adults. During the last decade, there has been a remarkable change in the treatment strategy of ASD, shifting the therapeutic gold standard from surgery to transcatheter closure, along with refinements and the evolution of device technology. Reports on the outcome of transcatheter ASD closure have shown an excellent efficacy as well as a low complication rate. However, the procedural details and/or outcomes of this procedure may be influenced by several factors including morphologic characteristics of the defect, co-morbid diseases, as well as individual factors including age and weight of the patient. Because the risk-benefit relationship in both the very young and the elderly subsets of the patients has not been clearly defined yet, closure of an ASD with device may be potentially subtracted from the treatment option in these patient groups. In this article, we will review the basis for device closure in small children and elderly patients with ASD and provide an overview of the frequently encountered problems.

Kawasaki disease and hyponatremia.

Sirs, We read with great interest the recent contribution by Watanabe et al. in Pediatric Nephrology [1]. They reported that hyponatremia in Kawasaki disease (KD) is a common finding, which suggests severe inflammation. They suggested that renal salt wasting due to renal involvement might underlie the development of hyponatremia in their patients with KD. They also cited that the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in KD has sometimes been reported, and cerebral vasculitis is thought to be the etiology of SIADH in KD. Nakamura et al. [2] also recently reported that hyponatremia at the patient’s first visit to hospital might be a predictor of giant coronary aneurysm (>8 mm), which was not mentioned in Watanabe et al.’s study. Nakamura et al. speculated that the relationship between hyponatremia and giant coronary aneurysms is based on the permeability of the endothelium, severity of the illness, dehydration, duration of period with fever, and so forth [2]. Although the exact mechanism for the development of hyponatremia in KD remains unknown, the relationship between interleukin (IL)-6 or IL-1 beta and ADH secretion has been suggested [3, 4]. Mastorakos et al. [3] reported that plasma ADH levels were elevated after IL-6 injection in cancer patients, suggesting that IL-6 activated the magnocellular ADH-secreting neurons and that it might be involved in SIADH. Ohta et al. [4] reported four cases with hyponatremia due to SIADH, which seems to be related to inflammation. The plasma Na concentration decreased when the patients had fever and increased plasma C-reactive protein (CRP) level. In such conditions, plasma ADH and IL-6 concentrations were increased and there was a significant correlation between them. Therefore, they performed animal experiments to investigate the role of IL in the development of SIADH. Intravenous administrations of IL-1 beta increased ADH, atrial natriuretic hormone (ANH), and adrenocorticotropic hormone (ACTH). The changes in ADH and ACTH were abolished by the pretreatment with an intravenous administration of indomethacin. Also, the intravenous administration of IL-1 beta increased the urinary sodium excretion. The pretreatment of HS142-1, an ANH antagonist, abolished the increase in urinary sodium excretion induced by IL-1 beta. Based on these findings, they speculated that IL-6 and IL-1 beta play an important role in the development of SIADH associated with inflammation. These findings suggest that natriuresis in KD might be due to not only renal involvement but also cytokines, such as IL-6 or IL-1 beta. One of our authors reported that serum IL-6 was markedly elevated in the acute stage of KD and serum IL-6 positively correlated with the serum CRP level [5]. IL-1 beta is also recognized as a mediator of endothelial damage in KD [6]. Therefore, there is a possibility that these cytokines might involve the pathogenesis of hyponatremia due to SIADH rather than cerebral vasculitis in KD, although they did not measure serum and urinary osmolarity and urinary electrolytes. Further studies are necessary to elucidate the possible relationship between these cytokines and hyponatremia due to SIADH in KD. Pediatr Nephrol (2006) 21:1490–1491 DOI 10.1007/s00467-006-0242-z

Morphologic Characteristics and Relating Factors to the Need of Technical Modification in Transcatheter Closure of Large Atrial Septal Defect (>/=25 mm).

Background and Objectives The rigid coupling between the delivery wire and the right atrial disk has been occasionally encountered during transcatheter closure of atrial septal defect (ASD). Therefore the device frequently makes a perpendicular angle, and the leading edge of left atrial disk slips through the defect and prolapses into right atrium (RA) before it is properly placed in the septum. The purpose of this study is to investigate relating factors to the need of technical modification in transcatheter closure of large ASD and to evaluate relevant morphologic characteristics of atrial septal rim in this situation. Subjects and Methods From July, 2003 to May, 2007, 312 patients underwent transcatheter occlusion of ASD with Amplatzer Septal Occluder® (ASO, AGA medical corporation, Golden Valley, MN, USA) at Yonsei Cardiovascular Center and among them 109 patients had large ASD (≥25 mm) and these patients were enrolled in our study. Patients were divided into two groups according to the deploying methods of the device (Group I: standard method, Group II: modified methods). Assessments of the defects and its surrounding rims were made by echocardiography. Results There were no differences between 2 groups in age, body weight and height except for balloon-stretched diameter (stop-flow technique) and device size. Group II patients with modified methods showed larger balloon-stretched diameter and device size than group I patients with standard method. The mean length of anterosuperior (AS) rim in group II was significantly shorter than group I (p<0.05). As the size of the device used in procedure increased, there was a trend towards increase in the need of modified methods. Conclusion This study shows that AS rim deficiency and the size of ASD may be the relating factors to the need of technical modification in transcatheter closure of ASD. Therefore, when the initial try with standard method is not successful in large ASD with deficient AS rim, we suggest that changing strategy of implantation may save time and efforts and possibly reduce the risk of complications associated with prolonged procedure.

Cardiac manifestations of Henoch-Schoenlein purpura: IgA mediated vasculitis or Rheumatic fever?

Sir, We read with interest an article on BA case of HenochSchonlein purpura and rheumatic carditis with complete atrioventricular block. (Eur J Pediatr. 2006;165:395–7.)^ by Guven et al. [2]. They reported a 9-year-old boy who had Henoch-Schönlein purpura (HSP) and acute rheumatic fever with complete atrioventricular block. They also described that HSP with dysrhythmia was not previously reported in the literature and he was treated with salicylate and benzathine penicillin therapy. Cardiac manifestations of HSP are extremely rare, but if occur, they can lead to myocardial necrosis and death. Also, arrhythmia related to vasculitic process of HSP was also reported [7]. Osman et al. described a 63-year-old man with slow junctional rhythm and hypotension associated with HSP requiring transvenous ventricular pacing [7]. This patient died despite high-dose prednisone and azathioprine therapy and multiple sections from the atrium, including the area of the sinoatrial node, showed diffuse small-vessel leukocytoclastic vasculitis with fibrinoid necrosis and interstitial hemorrhages. Although there is little information in the literature concerning histological appearances of the cardiac lesions in HSP, Kereiakes et al. reported that depositions of IgA and C3 in intramyocardial vessel walls were found in a patient without any cardiac symptoms [5], suggesting that subclinical cardiac involvement in HSP might have been underestimated in the past. Recently, Kalyoncu et al. described a case who developed HSP, pulmonary hemorrhage, and active carditis related with previous rheumatic fever attack and died despite intensive treatment [4]. Therefore, cardiac involvement of HSP should always be considered at the same time even in patients presenting with rheumatic fever to prevent unexpected fatal situations. We suggest that the treatment should also be focused on the regimens effective in both conditions, such as methylprednisolone pulse [1, 6] and/or plasmapheresis [3, 8], in addition to classical therapy (salicylate and benzathine penicillin) of rheumatic fever.

Respiratory syncytial virus prevention in children with congenital heart disease: who and how?

Respiratory syncytial virus (RSV) is a major cause of respiratory infection in children. Most of the pediatric population have RSV infection before the age of 2, and recurrent infections are common even within one season. Chronic lung disease, prematurity, along with congenital heart disease (CHD) are major risk factors in severe lower respiratory infection. In hemo-dynamically significant CHD patients with RSV infection, hospitalization is usually needed and the possibility of treatment in intensive care unit and the use of mechanical ventilator support are known to increase. Therefore the prevention of RSV infection in CHD patients is mandatory. The current standard for RSV prevention is immunoprophylaxis by palivizumab. Immunoprophylaxis is recommended monthly in hemodynamically significant CHD patients, up to 5 months. Motabizumab, a second generation drug and newly developing RSV vaccines are also expected to play a key role in RSV prevention in the future. The prophylaxis of RSV infection in CHD patients is cost-effective in both the medical aspect of the patients as well as the socio-economic aspect. Therefore an effort to promote prevention should be made by not only the family of the patients but also by the government.

Comparison of multi-echo and single-echo gradient-recalled echo sequences for SPIO-enhanced Liver MRI at 3 T

AIMnTo assess the utility of a T2*-weighted, multi-echo data imaging combination sequenced on superparamagnetic iron oxide (SPIO)-enhanced liver magnetic resonance imaging (MRI) using a 3 T system.nnnMATERIALS AND METHODSnFifty patients underwent SPIO-enhanced MRI at 3 T using T2*-weighted, single-echo, gradient-recalled echo (GRE) sequences [fast imaging with steady precession; repetition time (TR)/echo time (TE), 126 ms/9 ms; flip angle, 30°] and multi-echo GRE (multi-echo data image combination) sequences (TR/TE, 186 ms/9 ms; flip angle, 30°). Three radiologists independently reviewed the images in a random order. The sensitivity and accuracy for the detection of focal hepatic lesions (a total of 76 lesions in 33 patients; 48 solid lesions, 28 non-solid lesions) were compared by analysing the area under the receiver operating characteristic curves. Image artefacts (flow artefacts, susceptibility artefacts, dielectric artefacts, and motion artefacts), lesion conspicuity, and overall image quality were evaluated according to a four-point scale: 1, poor; 2, fair; 3, good; 4, excellent. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the lesions were compared.nnnRESULTSnImage artefacts were more frequent with single-echo GRE (p<0.05). The mean scale of image quality assessment for flow, susceptibility, dielectric, and motion artefacts were 2.76, 3.13, 3.42, and 2.89 with single-echo, respectively, compared with 3.47, 3.43, 3.47, and 3.39, respectively, with multi-echo GRE. There was no significant difference in lesion conspicuity between single-echo (3.15) and multi-echo (3.30) GRE sequences. The overall image quality was significantly (p<0.05) better with multi-echo (3.37) than with single-echo GRE (2.89). The mean SNR and CNR of the lesions were significantly (p<0.05) higher on multi-echo (79±23 and 128±59, respectively) images than on single-echo (38±11 and 102±44, respectively) images. Lesion detection accuracy and sensitivity were not significantly different between the two sequences. Mean accuracies and sensitivities were 0.864 and 0.785 for single-echo and 0.847 and 0.785 for multi-echo GRE, respectively.nnnCONCLUSIONnAt 3 T, the T2*-weighted, multi-echo data image combination sequence performs comparably to the T2*-weighted, single-echo GRE sequence for SPIO-enhanced MRI with good overall image quality and a decrease in undesired artefacts.

Polytetrafluoroethylene-covered stent deployment in the setting of Kawasaki disease.

We read with great interest the recent contribution by Waki and Baba [1]. They reported an 8-year-old boy with Kawasaki disease (KD) who had a giant aneurysm with stenotic lesions in the right coronary artery, which was successfully treated by transcatheter implantation of a polytetrafluoroethylene (PTFE)-covered stent. A follow-up coronary angiogram 10 months later showed that the stenosis on both sides of the stent slightly progressed compared with that of 3months follow-up, but the patency of the stent was still well maintained. Therefore, they suggested that PTFE-covered stent could be a potential novel treatment of KD with a giant coronary aneurysm. However, we experienced a KD patient with a giant aneurysm who showed a total occlusion of the PTFE stents despite intensive anticoagulation [2]. A 6-year-old boy was admitted to our Cardiology unit for enlarging coronary artery aneurysm, which had been monitored for 28 months from the onset of KD. Selective coronary angiography and intravascular ultrasound (IVUS) showed giant aneurysmal changes of the left anterior descending artery (LAD) with large thrombi and tubular eccentric 90% luminal narrowing. Percutaneous transluminal coronary angioplasty was performed for a proximal stenotic lesion and 2 PTFE-coated stents (Abbott Vascular Devices, 3.0 3 16 mm, 3.0 3 19 mm) were implanted to cover the entire length of the stenosis and aneurysm cavity. Coronary angiogram and IVUS immediately after the procedure revealed the resolution of the stenosis and remarkable improvement of the blood flow. He was discharged in a good physical condition 10 days after the procedure with aspirin (100 mg/day), clopidogrel (25 mg/kg/day), and warfarin (4.5 mg/day). Noninvasive examinations were carried out every 3 months. There was no remarkable event and a follow-up coronary angiogram was performed 9 months after the procedure. It showed total occlusion of the LAD PTFE stents (TIMI 0) and coronary collaterals communicating with the left coronary system on selective right coronary angiography. Our case showed that a late stent occlusion could occur even after the successful implantation and intensive anticoagulation using aspirin, clopidogrel, and warfarin. The recent development of PTFE-covered stents and their use in various indications offers a new modality for the treatment of coronary aneurysms. However, some concerns have been created by other reports, showing late thrombo-occlusive events and neointimal hyperplasia of the PTFE-covered stents implanted for the treatment of coronary artery disease [3,4]. Cejna et al. [5] demonstrated PTFE-covered stent grafts have far less biocompatibility and more neointimal formation than standard bare stents in a sheep iliac artery model. Moreover, we suggest that among various indications of PTFE-covered stent implantation, a giant coronary aneurysm with KD should be given more special attention, since the intrinsic response of the coronary vessels during the procedure of angioplasty in KD might be more vulnerable to restenosis than other diseases. Suzuki et al. [6] found that the coronary arterial lesions in KD are still undergoing active remodeling many years after the onset of the disease. Progressive localized stenosis in KD consists of remarkable intimal thickening caused by proliferative dense smooth muscle cells and accumulation of fibrous tissue. They also mentioned that the intimal smooth muscle cells were stellate-shaped, indicating that these cells were actively proliferating. However, the use of high-pressure dilatation is inevitable for a complete and symmetric expansion of this relatively stiff stent design. Therefore, Gercken et al. [7] used high-pressure dilatation (>14 atm) in all patients with a mean final inflation pressure of 19.3 6 3.3 atm for successful implantation. Considering the different natural history of the coronary artery lesion in KD, we suggested that the inevitable high-pressure deployment might be a limitation of PTFE-covered stent in the setting of KD. Although catheter intervention for coronary artery stenotic lesions in