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Featured researches published by Maiko Tachi.


The Annals of Thoracic Surgery | 2012

Improving Outcomes of the Surgical Management of Right Atrial Isomerism

Noritaka Ota; Yoshifumi Fujimoto; Masaya Murata; Yuko Tosaka; Yujiro Ide; Maiko Tachi; Hiroki Ito; Ai Sugimoto; Kisaburo Sakamoto

BACKGROUND Patients with right atrial isomerism (RAI) have several cardiac malformations historically resulting in significant morbidity and mortality. We sought to assess whether current surgical strategies have improved the outcomes of patients with RAI. METHODS A retrospective review of our database from 1997 to 2010 identified 60 consecutive patients with RAI who underwent initial palliation at Mt. Fuji Shizuoka Childrens Hospital. All of the patients had a functional single ventricle. Of the 60 patients, 33 patients (51.7%) had obstructed total anomalous pulmonary venous drainage (TAPVD), 23 patients (40.3%) had significant (more than moderate) atrioventricular valvular regurgitation (AVVR), 7 patients (12.3%) had hiatus hernia, and 4 patients (6.7%) had major aortopulmonary collateral arteries. Pulmonary outflow atresia was present in 39 of the patients (65%), and 46 patients had systemic-to-pulmonary artery shunts. Of the 33 patients with TAPVD, 18 underwent repair of the condition at initial palliation, 9 others at the time of a Glenn operation, 2 more through a Fontan operation, and 4 at the interstage between palliative surgeries. Eight of the 23 patients with significant AVVR underwent atrioventricular valve repair at initial palliation, 8 others at the time of Glenn operation, 4 others at the time of Fontan operation, and 3 during the interstage between operations. An initial neonatal surgical procedure was performed in 30 patients (50%). The mean follow-up period for patients in the study was 53.1 months. RESULTS Operative mortality after initial palliation was 15.4% (4 of 26 patients) before 2003 and 17.6% (6 of 34 patients) after 2004 (p=NS). Five-year survival was 53.8% before 2003 and 81.7% after 2004 (p=0.035, log-rank test). A multivariate analysis identified persistent AVVR of more than moderate degree (p=0.04) as a factor associated with late mortality. CONCLUSIONS The outcomes of surgery for RAI are improving. Neonatal palliative surgery for RAI carries a high operative risk of early mortality, and persistent significant AVVR remains a risk factor for late mortality.


The Journal of Thoracic and Cardiovascular Surgery | 2010

Atrioventricular valve repair in patients with functional single ventricle

Tomohiro Nakata; Yoshifumi Fujimoto; Keiichi Hirose; Yuko Tosaka; Yujiro Ide; Maiko Tachi; Kisaburo Sakamoto

OBJECTIVE We aimed to evaluate surgical repair of atrioventricular valve regurgitation in patients with functional single ventricle. METHODS The medical records of 65 consecutive patients with functional single ventricle who underwent atrioventricular valve repair between January 1999 and October 2008 were reviewed retrospectively. Their characteristics were as follows: median age, 9.5 months; median weight, 6.0 kg; atrial isomerism, 31 patients; and hypoplastic left heart syndrome, 12 patients. Regurgitation was repaired at the palliative, Glenn, and Fontan stage in 21, 29, and 15 patients, respectively. RESULTS The overall survival was 79% and 70% at 1 and 5 years, respectively. The risk factors for mortality were age less than 3 months (P < .001), body weight less than 4 kg (P < .001), hypoplastic left heart syndrome (P = .001), concomitant Norwood (P < .001), and the palliative stage (P = .004) on the univariate analysis, and body weight less than 4 kg (P = .010, hazard ratio, 9.8; 95% confidence interval, 1.7-55.6) on the multivariate analysis. Twenty patients underwent reoperation (repairs in 15; replacements in 5), and freedom from reoperation at 1 and 5 years was 69% and 57%, respectively. Concomitant systemic-to-pulmonary shunt (P = .040) was a risk factor for reoperation on the univariate analysis. Of the 48 survivors, 38 underwent Fontan completion, 7 underwent the Glenn procedure, and 3 are awaiting the Glenn procedure. CONCLUSIONS The midterm results of atrioventricular valve repair in patients with functional single ventricle were favorable; however, young and small patients, especially those with hypoplastic left heart syndrome, still had poor outcomes.


European Journal of Cardio-Thoracic Surgery | 2009

Functional single ventricle with extracardiac total anomalous pulmonary venous connection

Tomohiro Nakata; Yoshifumi Fujimoto; Keiichi Hirose; Masaki Osaki; Yuko Tosaka; Yujiro Ide; Maiko Tachi; Kisaburo Sakamoto

OBJECTIVE The purpose of this study is to evaluate the surgical repair of functional single ventricle and extracardiac total anomalous pulmonary venous connection (TAPVC). METHODS Between January 1998 and December 2007, 26 consecutive patients underwent surgical repair of extracardiac TAPVC. Their characteristics were as follows: median age, 34 (range 0-744) days; median weight 3.2 (range 2.0-9.6) kg; supracardiac TAPVC, 11 patients; infracardiac, 5; mixed, 10; right atrial isomerism, 24; pulmonary atresia, 16; and obstructed TAPVC, 17. Concomitant procedures included systemic-to-pulmonary shunt in 9 patients, pulmonary artery banding in 5, ventricle-to-pulmonary artery shunt in 1, Norwood procedure in 1, bidirectional Glenn in 9, and Fontan procedure in 1. RESULTS The overall survival after the repair of TAPVC was 58% (95% confidence interval [CI], 39-77%) and 54% (95% CI, 34-73%) at 1 and 5 years, respectively. Of the 14 survivors (supracardiac, 9; infracardiac, 4; and mixed, 1), 12 underwent Fontan completion; 1, bidirectional Glenn; and 1 is awaiting bidirectional Glenn. Anastomotic stenosis did not occur, but recurrent pulmonary venous ostial stenosis (PVS) was observed in nine patients. Freedom from recurrent PVS was 56% (95% CI, 34-78%) at both 1 and 5 years. Reoperation for recurrent PVS was performed in six patients; of these patients, two underwent Fontan completion, but three with bilateral and multiple PVS declined. By Cox multivariate regression analysis, mixed TAPVC (p=0.001, hazard ratio, 13.4; 95% CI, 2.8-64.4) was a risk factor for mortality, and atrioventricular valve regurgitation, which required surgical intervention at the palliative stage (p=0.024, hazard ratio, 23.4; 95% CI, 1.5-363.4) was a risk factor for recurrent PVS. CONCLUSIONS The mid-term results of the surgical repair of functional single ventricle with supracardiac or infracardiac TAPVC are acceptable. The surgical treatment of patients with mixed TAPVC and with severe atrioventricular valve regurgitation is not promising, but can be improved.


The Journal of Thoracic and Cardiovascular Surgery | 2014

Is routine rapid-staged bilateral pulmonary artery banding before stage 1 Norwood a viable strategy?

Noritaka Ota; Masaya Murata; Yuko Tosaka; Yujiro Ide; Maiko Tachi; Hiroki Ito; Ai Sugimoto; Kisaburo Sakamoto

OBJECTIVE We adopted a policy of rapid-staged bilateral pulmonary artery banding (bPAB) before the Norwood (NW) procedure for all patients with hypoplastic left heart syndrome. We hypothesized that this strategy might mitigate some of the traditional risk factors and that postponing a major bypass procedure beyond the newborn period could have both short- and long-term benefits. The purpose of the present study was to evaluate the efficacy of this strategy with respect to the short-term outcomes. METHODS From 2008 to 2010, 14 patients underwent bPAB and maintenance of ductal patency with prostaglandin E1 infusion before stage 1 NW. For reference, we also reviewed the data from patients who had undergone the primary NW procedure in the 2 years immediately before the study period. RESULTS The bPAB was performed at a median age of 6 days (range, 2-39), gestational age of 38.5 weeks (range, 36-41), and weight of 2.75 kg (range, 2.3-3.6). The subsequent NW was performed at a gestational age of 43.5 weeks (range, 41-51) and weight of 3.2 kg (range, 2.2-4.9). When the NW procedure was eventually performed on the pBAB group, the maximum blood lactate levels within the first 24 hours after the NW were lower than those in the earlier primary NW group (2.8±0.9 vs 10.1±6.5 mmol/dL, P=.0002) and the urine output in the first 24 hours after the NW was greater in the pPAB group (4.1±2.1 vs 2.2±1.5 mL/kg/h; P=.0051). CONCLUSIONS These data suggest that rapid-staged bPAB before NW can reduce the challenge of postoperative management in the early postoperative period after the NW procedure and have potential to improve the outcomes.


Interactive Cardiovascular and Thoracic Surgery | 2013

Technical modification enabling pulmonary valve-sparing repair of a severely hypoplastic pulmonary annulus in patients with tetralogy of Fallot

Hiroki Ito; Noritaka Ota; Masaya Murata; Yuko Tosaka; Yujiro Ide; Maiko Tachi; Ai Sugimoto; Kisaburo Sakamoto

OBJECTIVES Although pulmonary valve-sparing repair is preferable for patients with tetralogy of Fallot, the repair of very small pulmonary valves is challenging. The present study evaluates our modification for preserving severely hypoplastic pulmonary valves in patients with tetralogy of Fallot. METHODS Sixty-eight consecutive patients who underwent complete repair of a tetralogy of Fallot between 2005 and 2011 were retrospectively reviewed. Patients with pulmonary atresia, absence of a pulmonary valve, atrioventricular septal defect and/or subarterial ventricular septal defect were excluded. There were 19 (28%) patients with a severely hypoplastic pulmonary annulus determined by preoperative echocardiography (z-score <-4). For these patients, we collected echocardiographic data and information about their postoperative course. RESULTS Valve preserving was successful in 11 of 19 (58%) of the z < -4 group, compared with 48 of 49 (98%) of the z > -4 group. In the z < -4 valve-sparing subgroup (n = 11), the preoperative pulmonary valve diameter z-score was -4.9 (range -6.3 to -4.3), and an approach involving ventriculotomy with no transannular patch was employed at a mean age of 6.9 (range 2.2-16.1) months. In this subgroup, residual right ventricular outflow tract velocity was 2.4 ± 0.6 m/s at discharge from the hospital. During a mean follow-up of 2.6 ± 2.4 years, no reintervention was necessary. Late right ventricular outflow tract velocity was 2.2 ± 0.6 m/s, and there was no severe pulmonary regurgitation. The pulmonary valve annulus grew in relation to the patients body surface area (z = -0.51, range -4.2-0.24) without any aneurysmal changes in the right ventricular outflow tract. CONCLUSIONS Although our modification of valve-sparing repair for severely hypoplastic pulmonary valves in patients with tetralogy of Fallot could not be applied in all patients, this strategy enabled acceptable growth of the valve annulus, with only mild stenosis during the early to mid-term follow-up. This modification seems to be an option, even for a very small pulmonary valve.


The Annals of Thoracic Surgery | 2012

Impact of Postoperative Hemodynamics in Patients With Functional Single Ventricle Undergoing Fontan Completion Before Weighing 10 Kg

Noritaka Ota; Yoshifumi Fujimoto; Masaya Murata; Yuko Tosaka; Yujiro Ide; Maiko Tachi; Hiroki Ito; Ai Sugimoto; Kisaburo Sakamoto

BACKGROUND Although the Fontan procedure is now being performed in younger patients, the influence of the early timing of Fontan on midterm to long-term results remains unclear. We investigated whether the timing of Fontan completion affects subsequent hemodynamics in patients with functional single ventricle followed for more than 3 years. METHODS Between January 1997 and December 2008, 163 patients with functional single ventricle underwent extracardiac total cavopulmonary connection (TCPC) at a single institution. The survivors routinely underwent postoperative catheterization at 1 year and then every 5 years after TCPC and were divided into group A (weight < 10 kg; n = 65) and group B (weight > 10 kg; n = 97), and retrospectively reviewed. RESULTS Mean follow-up was 6.6 ± 3.7 years. Mean weight and conduit size were 8.5 ± 0.8 kg and 17.1 ± 1.2 mm for group A versus 20.2 ± 13.1 kg and 18.8 ± 1.9 mm for group B, respectively (p < 0.001). There were 3 hospital deaths (group A, n = 1; group B, n = 2) and 5 late deaths (group A, n = 3; group B, n = 2). No TCPC was taken down. There were no thromboembolic events in either group. The end-diastolic volume of ventricle (eDV) (% of normal) was (232.7 ± 91.4 before TCPC versus 139.3 ± 57.2 5 years after TCPC; p < 0.001) in group A and (209.6 ± 77.7 before TCPC versus 136.7 ± 61.4 5 years after TCPC; p < 0.001) in group B. Ventricular ejection fraction and cardiac index at 5 years were similar in both groups. The end-diastolic pressure of ventricle (eDP) (mm Hg) at 1 year (p = 0.0037) and at 5 years (p = 0.047) was significantly lower in group A compared with group B. CONCLUSIONS TCPC can be performed earlier with good intermediate results. Earlier unloading of a univentricular heart by means of TCPC might be advantageous for preservation of future ventricular function.


European Journal of Cardio-Thoracic Surgery | 2010

Fontan completion in patients with atrial isomerism and separate hepatic venous drainage

Tomohiro Nakata; Yoshifumi Fujimoto; Keiichi Hirose; Masaki Osaki; Yuko Tosaka; Yujiro Ide; Maiko Tachi; Kisaburo Sakamoto

OBJECTIVE Fontan completion in patients with atrial isomerism, in which the inferior vena cava (IVC) and the hepatic vein (HV) drain separately, is technically challenging. Herein, we review our surgical approach to these patients. METHODS The medical records of 50 consecutive patients with atrial isomerism who underwent Fontan completion between 1998 and 2008 were reviewed retrospectively. RESULTS Separate HV drainage was present in 17 patients. Patients with interrupted IVC were excluded. Patient characteristics were as follows: median age, 26 months (range 15-149); median weight, 9.6 kg (range 8.1-47.2); right atrial isomerism, 16 patients; and left atrial isomerism, one. The IVC and the separate HV at the level of diaphragm were contralateral in 16 patients, and ipsilateral in one. The surgical procedures for directing blood flow from the IVC and the separate HV to the pulmonary arteries were as follows: en bloc resection of the IVC and the HV and anastomosing these veins to an extracardiac conduit in 10 patients; connecting the IVC to the HV in a side-to-side fashion before anastomosing them to an extracardiac conduit in one; and lateral tunnel in another. When the IVC and the HV were widely separated by the vertebrae, we chose an intra-extracardiac conduit (intra-atrial septation) in four patients and an extracardiac conduit for the IVC and the right HV and lateral tunnel for the separate left HV in one. There was no mortality. Five re-operations were performed (pacemaker in two patients; one each of fenestration, release of outflow obstruction and ligation of collateral arteries). Sixteen patients underwent follow-up catheterisation, which revealed central venous pressure of 12.0 + or - 2.0 mmHg and arterial oxygen saturation of 92% + or - 6%. CONCLUSIONS The mid-term results of the Fontan completion in patients with atrial isomerism and separate HV drainage were excellent. The distance between the IVC and the separate HV and the position of the vertebrae should be considered when choosing a surgical technique.


European Journal of Cardio-Thoracic Surgery | 2014

Mid- to long-term aortic valve-related outcomes after conventional repair for patients with interrupted aortic arch or coarctation of the aorta, combined with ventricular septal defect: the impact of bicuspid aortic valve

Ai Sugimoto; Noritaka Ota; Chisato Miyakoshi; Masaya Murata; Yujiro Ide; Maiko Tachi; Hiroki Ito; Hironaga Ogawa; Kisaburo Sakamoto

OBJECTIVES Bicuspid aortic valve (BAV) is a common risk factor for valve-related problems and occurs more frequently in patients with an interrupted aortic arch (IAA) or coarctation of the aorta (CoA), combined with a ventricular septal defect (VSD), than in the general population. We have been using conventional repair for patients with IAA/CoA+VSD, including those with a very small aortic valve (AV). We retrospectively investigated the outcomes of these patients from the perspective of valve morphology. METHODS Between 2000 and 2012, 50 consecutive patients underwent conventional repair for CoA/IAA with VSD [one-stage repair, 44 (88%); staged repair, 6 (12%)]. The criteria for conventional repair were as follows: an AV annulus diameter (AVD) z-score of >-6.0; mitral valve annulus diameter z-score of >-3.0; without retrograde flow in the proximal arch. Sixteen (32%) patients had BAV (Group B); the remaining 34 (68%) patients had a tricuspid AV (Group T). The surgical outcomes in both groups were investigated. RESULTS No mortality occurred in the cohort. The median follow-up times were 6 years and 3 months (6 months to 11 years and 8 months) and 6 years and 2 months (4 months to 11 years and 4 months) in Groups B and T, respectively (P > 0.05). The preoperative data (median age at repair, median body weight and median AVD) were comparable in the two groups (P > 0.05). Two patients (4%) underwent reintervention in the aortic arch: 1 patient underwent balloon angioplasty for re-coarctation; the other removal of the interposed graft because of somatic growth. In both groups, the AVD became significantly larger at the 1-year follow-up, approximating the normal value. Three (6%) patients underwent a total of eight valve-related reinterventions (balloon angioplasty, 6; Ross operation, 1; valve replacement, 1). All three had BAV, and the AVD was 3.8-5.6 mm (z-score, -3.4 to -1.6). The 5-year valve-related reintervention-free survival rate was 76% and 100% in Groups B and T, respectively (P < 0.01). CONCLUSIONS The long-term outcomes after conventional repair under our criteria were acceptable. BAV was a significant risk factor for valve-related reinterventions after conventional repair for IAA/CoA with VSD.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 2010

Suprasternal approach for impending tracheo-innominate artery fistula

Yoshifumi Fujimoto; Keiichi Hirose; Noritaka Ota; Masaya Murata; Yujiro Ide; Yuko Tosaka; Maiko Tachi; Kisaburo Sakamoto

We report preventive innominate artery division or ligation through a suprasternal approach for impending tracheo-innominate artery fistula (TIF) with recurrent airway oozing in patients with severe neuromuscular disease. Our approach is less invasive and a favorable procedure as preventive surgery for impending TIF.


European Journal of Cardio-Thoracic Surgery | 2016

Efficacy of the ‘intrapulmonary-artery septation’ surgical approach for Fontan candidates with unilateral pulmonary arterial hypoplasia

Maiko Tachi; Masaya Murata; Yujiro Ide; Hiroki Ito; Kazuyoshi Kanno; Kenta Imai; Kisaburo Sakamoto

OBJECTIVES The bilaterally unbalanced development of pulmonary arteries (PAs), as a result of unilateral pulmonary arterial hypoplasia (PAhypo) makes patients either ineligible for the Fontan operation or candidates for the one-lung Fontan operation. In the present study, we examined the efficacy of intrapulmonary-artery septation (IPAS), a technique we reported in 2007 in which a septation is constructed within the central PA, in patients with unilateral PAhypo. METHODS Sixteen patients with unilateral PAhypo and an affected PA index of ≤60 mm(2)/m(2), including non-confluent PA (NCPA), underwent IPAS between January 2000 and March 2012; patients with pulmonary venous obstruction were excluded from this study. We compared the affected PA index values before and after IPAS and after the Fontan operation as well as the bilateral pulmonary blood flow ratio using pulmonary scintigraphy. The post-Fontan operation values of central venous pressure (CVP), pulmonary vascular resistance (PVR), ventricular end-diastolic pressure (VEDP), cardiac index (CI) and arterial oxygen saturation (SaO2) at the most recent cardiac catheterization, as well as the pre-IPAS and post-Fontan New York Heart Association (NYHA) classification levels were examined. RESULTS One patient died after IPAS (survival rate, 93.8%). Thirteen (86.7%) of the surviving 15 patients underwent the Fontan operation. The mean PA indexes were 25.5 ± 18.9 mm(2)/m(2) before IPAS and 67.9 ± 34.2 mm(2)/m(2) after IPAS (P = 0.003); the mean PA index was 71.1 ± 50.0 mm(2)/m(2) after the Fontan operation. Restenosis did not occur after the Fontan operation, and the PA diameters were maintained. The mean affected/unaffected lung blood flow ratio was 0.89 ± 0.67. The most recent cardiac catheterization after the Fontan operation indicated the following values: CVP, 11.7 ± 1.8 mmHg; PVR, 1.3 ± 0.4 U m(2); EDP, 5.7 ± 2.0 mmHg; CI, 3.1 ± 0.5 l/min/m(2) and SaO2, 94.9 ± 2.0%. The mean pre-IPAS and post-Fontan NYHA levels were 2.3 ± 0.6 and 1.2 ± 0.4, respectively (P = 0.0002). CONCLUSIONS With IPAS, the affected PA diameters increased significantly, and were maintained after the Fontan operation, and continuity of the native PAs was achieved. IPAS is very effective for patients suffering from otherwise intractable diseases.

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Kisaburo Sakamoto

Boston Children's Hospital

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Yujiro Ide

Boston Children's Hospital

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Hiroki Ito

Boston Children's Hospital

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Noritaka Ota

Boston Children's Hospital

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Yuko Tosaka

Boston Children's Hospital

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Ai Sugimoto

Boston Children's Hospital

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Keiichi Hirose

Boston Children's Hospital

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Hironaga Ogawa

Boston Children's Hospital

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