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Dive into the research topics where Akihiko Sekiguchi is active.

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Featured researches published by Akihiko Sekiguchi.


The Annals of Thoracic Surgery | 2003

Usefulness of pulsatile bidirectional cavopulmonary shunt in high-risk Fontan patients

Kagami Miyaji; Munehiro Shimada; Akihiko Sekiguchi; Akira Ishizawa; Takayoshi Isoda

BACKGROUND A bidirectional cavopulmonary shunt has been performed for the high-risk Fontan patient. It is well known that in the presence of the bidirectional cavopulmonary shunt alone to secure pulmonary blood flow, the central pulmonary artery size decreases over time. We have performed pulsatile bidirectional cavopulmonary shunt (PBCPS), keeping pulmonary blood flow from the ventricle through the stenotic pulmonary valve, or a Blalock-Taussig shunt in patients who do not meet the criteria for the Fontan operation. METHODS Eleven patients who underwent PBCPS between 1989 and 1993 were reviewed. We compared the results of cardiac catheterization immediately before PBCPS and during the postoperative observation period (310 +/- 257 days). RESULTS Pulmonary blood flow and arterial oxygen saturation increased significantly after PBCPS (p = 0.01). Pulmonary artery area index showed a tendency to increase (p = 0.11). The mean number of risk factors for the Fontan procedure decreased significantly for 1.8 +/- 1.1 to 0.7 +/- 0.8 after PBCPS (p < 0.05). Overall, 5 of the 11 patients (45.5%) met the criteria for the Fontan procedure, and a fenestrated Fontan procedure was carried out in 4 of them. CONCLUSIONS The PBCPS is useful for high-risk Fontan patients not only in the staged Fontan operation, but also as definitive palliation.


The Annals of Thoracic Surgery | 2002

Mortality of pulmonary artery banding in the current era: recent mortality of PA banding.

Hiroo Takayama; Akihiko Sekiguchi; Masahide Chikada; Mio Noma; Akira Ishizawa; Shinichi Takamoto

BACKGROUND The mortality of pulmonary artery banding improved significantly in the 1980s. However, we lack information on this procedure in the current era. METHODS The results of pulmonary artery banding in 365 patients who had operations between 1966 and 2001 were reviewed. The patients were divided into three groups: (1) group 1 patients who had operations between 1966 and 1979, (2) group 2 patients who had operations between 1980 and 1989, and (3) group 3 patients who had operations between 1990 and 2001. RESULTS Significantly younger and smaller patients have been operated on recently (mean age: group 1, 169.0 +/- 40 days; group 2, 101.8 +/- 11 days; and group 3, 69.7 +/- 8.9 days; and mean weight: 4.6 +/- 0.1, 4.1 +/- 0.1, and 3.2 +/- 0.1 kg, respectively). A decrease was found in the number of simple cardiac anomalies, such as isolated ventricular septal defects. The early mortality in the three groups was 38.3% for group 1 (65 of 187), 13.5% for group 2 (15 of 111), and 13.8% for group 3 (12 of 87). Although the mortality did not vary significantly between groups 2 and 3, it improved over time in patients weighing less than 3 kg. Multivariate analysis of group 3 demonstrated that no isolated variable, including sex, weight, and diagnosis was a significant risk factor. CONCLUSIONS Despite the advances in perioperative management, we found no improvement in the early mortality of pulmonary artery banding during the last decade. These results will support the preference for primary repair of intracardiac anomalies in small infants. However, this operation can now be performed with the same risk even in smaller patients. We believe that pulmonary artery banding has a role in the treatment of congenital cardiac anomalies.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 2001

Successful Surgical Management of a Tracheopulmonary Artery Fistula Caused by an Intratracheal Expandable Metal Stent

Takashi Miyamoto; Ryoichi Ishida; Mio Noma; Masahide Chikada; Akihiko Sekiguchi

We describe a boy who underwent slide tracheoplasty and relocation of the left pulmonary artery at 3 months of age to treat pulmonary artery sling with congenital tracheal stenosis. Persisting tracheal stenosis required that he have a Palmaz stent inserted on postoperative day 77. He developed massive hemoptysis after the fourth attempt to expand the stent balloon and immediate computed tomography showed a tracheopulmonary artery fistula. Using cardiopulmonary bypass, we conducted emergency surgery to successfully manage the fistula. He currently depends on mechanical ventilation.


Heart and Vessels | 2002

Structural differences in the cytoarchitecture and intercalated discs between the working myocardium and conduction system in the human heart

Takashi Miyamoto; Lei Zhang; Akihiko Sekiguchi; Tetsuo Hadama; Tatsuo Shimada

Abstract. Working and specialized cardiac myocytes and their intercalated discs in adult human hearts without history of cardiac disease were examined by scanning electron microscopy. The NaOH/ultrasonication treatment of cardiac tissues resulted in the digestion of connective tissue and separation of intercellular junctions. Auricular and ventricular working cardiac myocytes were quasi-cylindrical in shape, bifurcated, and connected end-to-end at the intercalated discs. The intercalated discs in the working cardiac myocytes showed a stair-like profile, consisting of steps (plicate segments) and corresponding risers (interplicate segments). The ventricular myocytes, in particular, had many steps and risers. The plicate segments were filled with numerous finger-like microprojections. The strands of the myocytes in the sinoatrial node were oriented linearly, while those in the atrioventricular node formed a reticular network. The intercalated discs in both nodal cells were underdeveloped, having few microprojections. Myocytes in the atrioventricular bundle (His) and the right limb were arranged in parallel, and were characterized by the presence of slender branches. Purkinje cell strands formed reticular networks. The intercalated discs in the His-Purkinje system were irregular in appearance, and the microprojections were larger in size and smaller in number than those of working myocytes. The myocytes in the crista terminalis and surrounding the fossa ovalis resembled cells in the His-Purkinje system rather than auricular working myocytes in morphology, and may act as the internodal pathway. It is concluded that morphological differences in both the cytoarchitecture and intercalated discs were closely related with contraction and impulse propagation in the various regions of the human heart.


The Annals of Thoracic Surgery | 2002

Dilatable banding of a Blalock-Taussig shunt

Masahide Chikada; Akihiko Sekiguchi; Shinichi Oho; Takashi Miyamoto; Ryouichi Ishida; Hiroo Takayama; Akira Ishizawa

Dilatable banding has been used in various situations. Sometimes Blalock-Taussig shunt banding is performed to prevent pulmonary overcirculation. Recently several reports have described dilatable pulmonary artery banding. We modified these methods for flow control of a Blalock-Taussig shunt. We report the case of a neonate with truncus arteriosus in which this technique was used.


Congenital Heart Disease | 2007

Fate of Equine Pericardial Roll Conduit for Rastelli Operation during Long-term Follow-up

Koh Takeuchi; Arata Murakami; Akihiko Sekiguchi; Yasutaka Hirata; Katsuhide Maeda; Kazuo Kitahori; Yoshio Doi; Shinichi Takamoto

BACKGROUND Right ventricular outflow tract obstruction is a frequent condition after Rastelli operation. Although several modifications have been reported elsewhere, ideal conduit has not been developed yet during long-term follow-up. We reviewed our experiences over 15-year long-term follow-up with patients who underwent Rastelli operation using house-made equine pericardial roll graft. METHODS Since June 1981, 16 patients underwent Rastelli operation with the pericardial roll graft. Median follow-up time was 15.6 years (7.3-26.8 years). RESULTS Twelve out of 16 patients using pericardial roll graft with (n = 6) or without (n = 6) cusps underwent 13 reoperations during the follow-up period. Median time from first Rastelli to re-do operation was 8.4 years with median time to reoperation of 8 years. Major indication for reoperation was conduit obstruction (n = 10), but not conduit regurgitation. Conduit problem includes kinking and compression of the graft. Reoperation procedures include 7 Danielson procedures, 2 patch augmentations, 1 homograft replacement, 1 pericardial roll graft, 1 expanded polytetrafluoroethylene tube graft replacement, and 1 patch closure for pulmonary artery aneurysm. Balloon angioplasty was not effective for pericardial roll conduit stenosis. CONCLUSION We conclude that house-made equine pericardial roll graft was durable for certain time period, but conduit change may be inevitable. Because of excellent handling and wide application, further modification may be warranted.


Clinical Pediatric Endocrinology | 2004

Virilizing Adrenocortical Carcinoma Invading the Right Atrium with Histological High-Grade Malignancy and p53 Mutation in a 3-Year-Old Child: Indication of Post Operative Adjuvant Chemotherapy.

Keisuke Nagasaki; Reiko Horikawa; Junichi Nagaishi; Toshiro Honna; Akihiko Sekiguchi; Yukiko Tsunematsu; Toshiaki Tanaka

We present a 3-yr-old girl with a virilizing adrenocortical carcinoma invading into the right atrium with histological high-grade malignancy and p53 mutation. Development of facial acne and pubic hair were noted at 3 yr and 2 mo. The levels of androgens were high. Diurnal variation in ACTH and cortisol were absent. Abdominal computed tomography revealed a large right suprarenal mass, with extension into the inferior vena cava and right atrium. Based on the diagnosis of a right virilizing adrenocortical tumor with Cushing syndrome, surgery was performed by a combined thoracoabdominal approach with the patient on cardiopulmonary bypass. The tumor was 7 × 5.5 × 3.5 cm in size, and weighed 95 g. The histological diagnosis was adrenocartical carcinoma with high-grade malignancy according to the category of Weiss. A heterozygous mutation of the p53 tumor-suppressor gene (codon 248 CGC→TGG) was found. We did not perform adjuvant chemotherapy because of radical resection on macroscopic observation and no metastasis in radiological findings. Five months after the surgery, her chest X ray and computed tomography revealed multiple lung metastases and a single liver metastasis. In this type of patient with histological high-grade malignancy and p53 mutations, postoperative adjuvant chemotherapy is indicated even if macroscopic total surgical removal had been performed.


The Annals of Thoracic Surgery | 2001

Direct closure of ostium primum defect in the repair of atrioventricular septal defect

Masahide Chikada; Akihiko Sekiguchi; Takashi Miyamoto; Mio Matsuzaki; Ryouichi Ishida; Akira Ishizawa

BACKGROUND Patch closure is generally performed for atrial septation of an atrioventricular septal defect. We recently developed a new surgical technique for repairing atrioventricular septal defects that avoids the use of any patch material for closing the atrial septal defect. We report our experience with this procedure. METHODS Seven patients (complete type: 5, partial type: 2) underwent this new operation. The diameters of the atrial septal defects were measured by transesophageal echocardiography. The preoperative electrocardiograms were compared with those taken after the operations. RESULTS Diameters of the atrial defects ranged from 3 to 10 mm. Electrocardiograms before and after the operations did not change. No significant atrioventricular valve regurgitation and no residual shunts were detected by postoperative echocardiography. CONCLUSIONS This method simplifies the repair of atrioventricular septal defects. In the short-term results, no arrhythmia and no valve regurgitation was seen.


Interactive Cardiovascular and Thoracic Surgery | 2003

Mitral valve replacement in a 15-month-old infant with infective endocarditis

Akihiko Sekiguchi; Masahide Chikada; Kunihiko Tonari

This report describes a 15-month-old child without particular heart problems, presenting prolonged high-grade fever, an impaired level of consciousness, right hemiparesis and cutaneous lesion on admission. Medication was started according to the initial diagnosis of bacterial or viral meningitis, however, congestive heart failure was suddenly observed 15 days after the admission. Echocardiography revealed a mass in the right atrium, and mitral valve regurgitation due to the irregularly thickened and aneurysmal anterior leaflet with a perforation, consistent with infective endocarditis. Mitral valve replacement with a mechanical prosthesis was performed and the postoperative course was uneventful.


The Annals of Thoracic Surgery | 1995

Pulmonary atresia with intact ventricular septum: Long-term results of “One and a Half Ventricular Repair”

Kagami Miyaji; Munehiro Shimada; Akihiko Sekiguchi; Akira Ishizawa; Takayoshi Isoda; Minoru Tsunemoto

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Akira Ishizawa

Boston Children's Hospital

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Masahide Chikada

Boston Children's Hospital

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Munehiro Shimada

Boston Children's Hospital

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Hiroo Takayama

Columbia University Medical Center

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Kagami Miyaji

Boston Children's Hospital

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Masahide Chikada

Boston Children's Hospital

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