Noritaka Ota

Improving Outcomes of the Surgical Management of Right Atrial Isomerism

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.

Feasibility of the extracardiac conduit Fontan procedure in patients weighing less than 10 kilograms

OBJECTIVE The extracardiac conduit Fontan procedure has led to improved outcomes. We performed the procedure in patients weighing less than 10 kg and evaluated its feasibility. METHODS Since January 1999, 72 patients weighing less than 20 kg underwent extracardiac conduit Fontan procedure with polytetrafluoroethylene conduits. The patients were divided into 2 groups: 36 patients weighing less than 10 kg in group S and 36 weighing more than 10 kg in group L. Mean weight, median age, and median follow-up period in groups S and L were 8.5 +/- 1.1 and 14.0 +/- 3.0 kg, 18.9 and 42.0 months, and 29.2 (1.7-79.7) and 42.1 (2.8-94.2) months, respectively. Postoperatively, most patients received peritoneal drainage catheters. We reviewed data precatheterization and postcatheterization and postoperative course. RESULTS Conduit sizes in groups S and L were 17.0 +/- 1.3 and 17.9 +/- 1.9 mm, respectively (P = .03). Five patients required fenestrations. There were 2 hospital deaths, 1 in each group, and 2 late deaths in group S. The postoperative course was identical in both groups, except for median length of stay in the intensive care unit and peritoneal drainage volume. Group S versus L: ventilator support, 11 versus 7 hours; pleural drainage, 9 days each; pleural drainage greater than 14 days, 6 versus 5 cases; peritoneal drainage, 8 versus 7 days; intensive care unit stay, 7 versus 4 days (P = .01), peritoneal drainage volume, 26.1 versus 14.1 mL x kg x d(-1) (P = .0007). CONCLUSIONS The early outcome of the extracardiac conduit Fontan procedure was satisfactory in patients weighing less than 10 kg. However, the required size of the conduit remains debatable.

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

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.

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

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.

Improving results of atrioventricular valve repair in challenging patients with heterotaxy syndrome.

OBJECTIVES Heterotaxy syndrome, which is often associated with atrioventricular valvar regurgitation, has been considered a risk factor for the surgical repair for Fontan candidates. The results of atrioventricular valve repair in this challenging patient population remain largely unknown. METHODS From July, 1994 to January, 2007, 25 patients with the heterotaxy syndrome consisting of 22 right isomerism and three left isomerism presented to the Shizuoka Childrens Hospital Japan with significant (3-4+) atrioventricular valvar regurgitation necessitating atrioventricular valve repair. The clinical and Doppler/echocardiographic data were retrospectively reviewed to determine the efficacy of the repair and patient outcome. RESULTS Patients were divided into two groups on the basis of atrioventricular valvar regurgitation at the most recent follow-up: those with a successful late outcome, (0-2) and those with a poor outcome (3-4). There were 17 (67%) patients with a successful outcome and 8 (33%) with a poor outcome. The repair technique including leaflet apposition was predictive of a successful outcome (p = 0.003). Overall survival was 64% (16/25). Survival was 88.2% (15/17) for patients with a successful result versus 12.5% (1/8) for those with a poor outcome (p = 0.0007). Of the 15 survivors, 13 have reached final completion of the Fontan circulation, and two currently remain at the bi-directional Glenn shunt stage. CONCLUSION Atrioventricular valve repair can be accomplished in this challenging patient population with excellent results. The combination of the leaflet apposition technique and the Kay suture can be performed with an excellent outcome in the majority of patients with heterotaxy syndrome, even with significant atrioventricular valvar regurgitation.

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

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.

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

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.

Suprasternal approach for impending tracheo-innominate artery fistula

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.

Pulmonary haemorrhage due to an aortopulmonary collateral artery after arterial switch

A neonate with transposition of the great arteries and intact ventricular septum presented without pulmonary over-circulation, and subsequently developed pulmonary haemorrhage after corrective surgery. Postoperative CT revealed an aortopulmonary collateral artery arising from the descending aorta, and we performed successful embolisation on postoperative day 9. Aggressive imaging modalities such as angiography and/or CT imaging with contrast can detect unexpected extra-pulmonary blood supply and guide further management.

Primary Arterial Switch Operation for Late Referral of Transposition of the Great Arteries with Intact Ventricular Septum in the Current Era: Do We Still Need a Rapid Two-Stage Operation?

Objective: We introduced primary arterial switch operation for the patient with transposition of great arteries and intact ventricular septum (TGA-IVS) who had more than 3.5 mm of posterior left ventricle (LV) wall thickness. Methods: Between January 2013 and June 2015, a total of 116 patients underwent arterial switch operation. Of the 116 patients, 26 with TGA-IVS underwent primary arterial switch operation at more than 30 days of age. Results: The age and body weight (mean ± SD) at the operation were 120.4 ± 93.8 days and 4.1 ±1.0 kg, respectively. There was no hospital mortality. The thickness of posterior LV wall (preoperation vs postoperation; mm) was 4.04 ± 0.71 versus 5.90 ± 1.3; P < .0001; interval: 11.8 ± 6.5 days. The left atrial pressure (mm Hg; postoperative day 0 vs 3) was 20.0 ± 3.2 versus 10.0 ± 2.0; P < .0001; and the maximum blood lactate level (mmol/dL) was 4.7 ± 1.4 versus 1.4 ± 0.3; P < .0001, which showed significant improvement in the postoperative course. All cases had delayed sternal closure. The patients who belonged to the thin LV posterior wall group (<4 mm [preoperative echo]: n = 13) had significantly longer ventilation time (days; 10.6 ± 4.8 vs 4.8 ± 1.7, P = .0039), and the intensive care unit stay (days) was 14 ± 9.2 versus 7.5 ± 3.5; P = .025, compared with thick LV wall group (≥4.0 mm: n = 13). Conclusions: The children older than 30 days with TGA-IVS can benefit from primary arterial switch operation with acceptable results under our indication. However, we need further investigation for LV function.