Kisaburo Sakamoto

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.

Atrioventricular valve repair in patients with functional single ventricle

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.

Functional single ventricle with extracardiac total anomalous pulmonary venous connection

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.

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.

Surgical treatment of coronary sinus orifice atresia with hypoplastic left heart syndrome after total cavo-pulmonary connection

Atresia of the coronary sinus orifice is rare. We describe the surgical treatment of coronary orifice atresia in an infant with a persistent left superior vena cava after total cavo-pulmonary connection for hypoplastic left heart syndrome. The diagnosis was made by cardiac catheterization after total cavo-pulmonary connection at 8 months of age. After surgery, cardiac performance deteriorated. At reoperation, the coronary sinus was fenestrated to the left atrium. The patient survived surgical treatment of coronary sinus ostial atresia unroofed to the left atrium, guiding the placement of the fenestration with a probe placed through the open cardiac end of left superior vena cava.

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.

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

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.