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Publications (7)22.56 Total impact

  • Article: Outcomes of Aortopexy for Patients With Congenital Heart Disease.
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    ABSTRACT: Aortopexy is a surgical procedure in which the aortic arch is fixed at other structures, thus widening the interaortic space. This study aimed to evaluate the outcome of aortopexy by means of chest computed tomography for patients with congenital heart disease. The study retrospectively reviewed the medical records of 16 patients with congenital heart disease who had undergone aortopexy by compressed airway. The severity of compressed bronchus before aortopexy, immediately after aortopexy (≤1 month), and after the patient had grown up were compared. To estimate the efficacy of the aortopexy, the interaortic distance index was calculated. Of the 16 patients, aortopexy was performed at the ascending aorta in 7, at the descending aorta in 7, and at the transverse arch in 2. The diameter ratio between the narrowest bronchus and the trachea was improved after aortopexy, as was the diameter ratio before aortopexy versus immediately after aortopexy (n = 9; p = 0.018) and the diameter ratio before aortopexy versus after the patient had grown up (n = 11; p = 0.006). Also, the interaortic distance index was increased after aortopexy, as was the diameter before aortopexy versus immediately after aortopexy (n = 9; p = 0.039) and the diameter before aortopexy versus after the patient had grown up (n = 11; p = 0.014). The study had one case of mortality due to sepsis. As shown by the results, aortopexy in patients with a compressed airway between arches is a useful surgical option. Such a compressed airway between arches should be considered for patients with an unusual clinical course before and after open heart surgery.
    Pediatric Cardiology 03/2013; · 1.30 Impact Factor
  • Article: An adolescent patient with coarctation of aorta treated with self-expandable nitinol stent.
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    ABSTRACT: Transcatheter treatment of aortic coarctation, with balloon angioplasty or stent implantation, is now an acceptable alternative to surgical repair. However these procedures may result in complications, such as vascular wall injury and re-stenosis of the lesion. A nitinol self-expandable stent, when deployed at the coarctation site, produces low constant radial force, which may result in a gradual widening of the stenotic lesion leaving less tissue injury ('stretching rather than tearing'). For an adolescent with a native aortic coarctation, a self-expandable stent of 20 mm diameter was inserted at the discrete stenotic lesion of 5 mm diameter without previous balloon dilatation procedure. No further balloon dilatation was done immediately after the stent insertion. With the self-expandable stent only, the stenosis of the lesion was partially relieved immediately after the stent deployment. Over several months after the stent insertion, gradual further widening of the stent waist to an acceptable dimension was observed.
    Korean Circulation Journal 03/2013; 43(3):207-11.
  • Article: Transcatheter Closure of Secundum Atrial Septal Defect in Patients Over 60 Years Old.
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    ABSTRACT: Atrial septal defect (ASD) is the one of most common congenital heart diseases detected in adults. Along with remarkable development of device technology, the first treatment strategy of secundum ASD has been transcatheter closure in feasible cases. However, there are only a few publications regarding the results of transcatheter closure of ASD in elderly patients, especially those over 60 years of age. We report our results of transcatheter closure of ASD in patients over 60 years old. Between May 2006 and December 2011, 31 patients over 60 years old (25 female and 6 male; mean 66.7±5.25 years old, range 61-78 years old) were referred to our center. A total of 23 patients underwent therapeutic catheterization to close secundum ASD, and the closure was successful in 22 patients (95.7%). All patients who underwent the procedure survived except for one patient who expired because of left ventricular dysfunction. A small residual shunt was observed in two (9%) of 21 patients before discharge but disappeared at follow-up. All patients eventually had complete closure. There were five patients who had coronary problems. One patient underwent percutaneous coronary intervention using a stent at the same time as transcatheter closure of ASD. Atrial arrhythmias were detected in 6 of 23 patients (26.1%) before the procedure. One patient was successfully treated by radiofrequency ablation before the procedure. No patients displayed new onset arrhythmia during the follow-up period. Follow-up echocardiographic evaluation showed a significantly improved right ventricular geometry. We conclude that transcatheter closure of ASD is a safe and an effective treatment method for patients over 60 years old if the procedure is performed under a thorough evaluation of comorbidities and risk factors.
    Korean Circulation Journal 02/2013; 43(2):110-114.
  • Article: Outcomes of pulmonary valve replacement in 170 patients with chronic pulmonary regurgitation after relief of right ventricular outflow tract obstruction: implications for optimal timing of pulmonary valve replacement.
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    ABSTRACT: The objectives of this study were to evaluate outcomes of pulmonary valve replacement (PVR) in patients with chronic pulmonary regurgitation (PR) and to better define the optimal timing of PVR. Although PVR is effective in reducing right ventricular (RV) volume overload in patients with chronic PR, the optimal timing of PVR is not well defined. A total of 170 patients who underwent PVR between January 1998 and March 2011 for chronic PR were retrospectively analyzed. To define the optimal timing of PVR, pre-operative and post-operative cardiac magnetic resonance imaging (MRI) data (n = 67) were analyzed. The median age at the time of PVR was 16.7 years. Follow-up completeness was 95%, and the median follow-up duration was 5.9 years. Overall and event-free survival at 10 years was 98% and 70%, respectively. Post-operative MRI showed significant reduction in RV volumes and significant improvement in biventricular function. Receiver-operating characteristic curve analysis revealed a cutoff value of 168 ml/m(2) for non-normalization of RV end-diastolic volume index (EDVI) and 80 ml/m(2) for RV end-systolic volume index (ESVI). Cutoff values for optimal outcome (normalized RV volumes and function) were 163 ml/m(2) for RV EDVI and 80 ml/m(2) for RV ESVI. Higher pre-operative RV ESVI was identified as a sole independent risk factor for suboptimal outcome. Midterm outcomes of PVR in patients with chronic PR were acceptable. PVR should be considered before RV EDVI exceeds 163 ml/m(2) or RV ESVI exceeds 80 ml/m(2), with more attention to RV ESVI.
    Journal of the American College of Cardiology 08/2012; 60(11):1005-14. · 14.16 Impact Factor
  • Article: Bicuspid pulmonary valve implantation using polytetrafluoroethylene membrane: early results and assessment of the valve function by magnetic resonance imaging.
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    ABSTRACT: OBJECTIVES: The durability of bioprosthetic valves in the pulmonary position is suboptimal. The objectives of this study were to evaluate the early results of polytetrafluoroethylene (PTFE) bicuspid pulmonary valve (PV) implantation and to better define the function of this valve by magnetic resonance imaging (MRI). METHODS: Fifty-six patients who underwent PTFE bicuspid PV implantation between June 2009 and August 2011 were retrospectively analysed. The median age was 17.5 years and median valve size was 26 mm. Fundamental diagnoses were tetralogy of Fallot (n = 38), pulmonary atresia with ventricular septal defect (n = 8), double outlet right ventricle (n = 7) and absent PV syndrome (n = 3). Thirty-two patients with pulmonary regurgitation (PR) underwent MRI preoperatively and 22 of them underwent follow-up MRI at a median of 6.7 months postoperatively. RESULTS: There was one early death. Postoperative echocardiography (n = 53) showed no or trivial PR in 49 patients and mild PR in 4. Median follow-up duration was 15.2 months. There was no late death or reoperation. Follow-up echocardiography (n = 41) performed at a median of 7.5 months postoperatively showed no or trivial PR in 33 patients and mild PR in 8 patients. Follow-up MRI showed a significant reduction in right ventricular volumes and improvement in biventricular function. The median PR fraction of this valve was 10%. CONCLUSIONS: Early results of bicuspid PV implantation using PTFE membrane were satisfactory. PTFE bicuspid PV demonstrated excellent performance for the short term as evidenced by echocardiography and MRI. Long-term follow-up is mandatory to determine the durability of this valve.
    European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 07/2012; · 2.40 Impact Factor
  • Article: Palliation Using a Self-expandable Stent in a Patient with Obstructive Right-Ventricular Outflow Tract after Total Correction of Tetralogy of Fallot : Self-expandable stent in Tetralogy of Fallot.
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    ABSTRACT: Total correction of tetralogy of Fallot (TOF) is typically performed within the first year of life. However, subsequently, right-ventricular dysfunction often progresses by pulmonary stenosis or regurgitation. Although most patients with corrected TOF require additional surgery for right-ventricular outflow tract, intervention could be an alternative to palliative surgery and associated morbidities, especially in children. We describe a palliative application of the self-expandable stent in a patient with pulmonary stenosis after total correction of TOF who lacked a conduit between the right ventricle and pulmonary artery.
    Pediatric Cardiology 03/2012; · 1.30 Impact Factor
  • Article: Durability of bioprosthetic valves in the pulmonary position: long-term follow-up of 181 implants in patients with congenital heart disease.
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    ABSTRACT: Durability of bioprosthetic valves in the pulmonary position is not well defined. We examined the durability of bioprosthetic valves in the pulmonary position and risk factors associated with bioprosthetic pulmonary valve failure. Between 1993 and 2004, 181 patients underwent pulmonary valve replacement using bioprostheses. Patients who underwent valved conduit or homograft implantation were excluded. Mean age was 14.2 ± 9.8 years and median valve size was 23 mm (range, 19-27 mm). Types of bioprosthesis used were Hancock II (n = 83), Perimount (n = 53), Freestyle (n = 23), Carpentier-Edwards porcine valve (n = 18), and others (n = 4). There were 3 early and 7 late deaths. Follow-up completeness was 88.6% and mean follow-up duration was 7.3 ± 2.9 years. Forty-three patients underwent redo pulmonary valve replacement. Overall freedom from redo pulmonary valve replacement at 5 and 10 years was 93.9% ± 1.9% and 51.7% ± 8.6%, respectively. Overall freedom from both valve failure and valve dysfunction at 5 and 10 years was 92.2% ± 2.1% and 20.2% ± 6.7%, respectively. In multivariable analysis, younger age at operation, diagnosis of pulmonary atresia with ventricular septal defect, and use of stentless valve were identified as risk factors for redo pulmonary valve replacement. Durability of bioprosthetic valves in the pulmonary position was suboptimal. Valve function was maintained stable until 5 years after operation. By 10 years, however, about 80% will require reoperation or manifest valve dysfunction. In our experience, the stentless valve was less durable than stented valves.
    The Journal of thoracic and cardiovascular surgery 01/2011; 142(2):351-8. · 3.41 Impact Factor