The effect of the conduit size on middle-term outcomes in patients with extracardiac total cavopulmonary connection.

OBJECTIVES: The 18- and 16-mm conduits in extracardiac total cavopulmonary connection (eTCPC) were reported to be optimal based on energy loss and flow stagnation at the relatively early phase. However, because the artificial conduit lacks growth potential, we have recently encountered some cases in which the conduit needs to be changed several years after eTCPC. These cases prompted us to reconsider the surgical strategy for eTCPC. METHODS: We reviewed our 20-year single-centre experience with eTCPC patients (n = 256) to compare the 18-mm conduit (n = 195) and 16-mm conduit (n = 61) in terms of mortality and morbidity. RESULTS: The 16-mm conduit was used significantly more frequently in patients whose main chamber was right ventricle (P < 0.001). There was also a significant difference in preoperative inferior vena cava pressure (P = 0.008). There was a significant difference in the actuarial rate of freedom from late-occurring complications, including mortality, between the 2 groups (P = 0.003). There was a significant difference in the actuarial rate of reoperation-free survival (P = 0.042); however, there was no significant difference in resurgical intervention for the conduit (P = 0.333). In multivariate analysis, preoperative inferior vena cava pressure was an independent predictor for late-occurring complications (hazard ratio 1.19; P = 0.026). Conduit size (18 or 16 mm) itself was not an independent predictive factor for late-occurring complications (P = 0.690). CONCLUSIONS: The mid-term clinical outcomes in patients who underwent eTCPC were excellent with low mortality. Preoperative inferior vena cava pressure was the only predictive risk factor for postoperative morbidity, and the 16 mm conduit was not predictive thereof.

Mitral and tricuspid valve repair using interannular bridging in children.

OBJECTIVES: In children, it is difficult to control mitral valve (MV) or tricuspid valve (TV) regurgitation with conventional procedures alone because complex factors hamper easy improvement of valve coaptation. We investigated interannular bridging in children with MV/TV regurgitation. METHODS: The subjects were 9 patients who underwent interannular bridging to control TV or MV regurgitation between January 2014 and December 2021. We analysed reintervention for the valve, progression of stenosis/regurgitation and valve growth. RESULTS: The TV and MV groups included 4 and 5 patients, respectively. At operation, the median age was 5.8 (1.4-14) years in TV and 3.6 (0.3-7.0) years in MV. The median weight was 13.0 (8.4-41.2) kg in TV and 11.0 (4.8-18.3) kg in MV. The median follow-up periods were 78 (11-94) months for TV and 30 (4-34) months for MV. None of the patients in either group underwent reintervention. Moderate or greater regurgitation recurred in 1 TV patient but subsequently improved to mild regurgitation. Valve stenosis (mean diastolic pressure gradient >10 mmHg) was not detected. The median valve diameter (Z-score) ranged from -1.17 (-3.7 to 0.85) at discharge to -0.59 (-1.2 to 2.01) at the latest follow-up in TV patients. In MV patients, valve diameter changed from 1.14 (-1.68 to 1.46) to 0.72 (-0.23 to 1.36). After bridging, the coaptation height was maintained at the same value over time. CONCLUSIONS: Interannular bridging could be a useful approach for complicated TV/MV regurgitation in children.

Hepatic-to-azygos vein redirection after a failed bifurcated graft Fontan conversion.

A successful hepatic-to-azygos vein redirection was performed in a patient with absent inferior vena cava using a long vascular graft to address a pulmonary arterio-venous fistula after a failed Fontan conversion. No exacerbation was observed 5 years postoperatively.

Catheter Intervention for Flow Regulatory Clips on Palliative Shunts and Conduits in Patients with Congenital Heart Disease.

Catheter intervention (CI) for a Blalock-Taussig shunt (BTS) or a ventricle-to-pulmonary artery conduit (VPC) is often required after a palliative surgery for congenital heart disease. Flow regulatory clips help improve interstage mortality; their use necessitates CIs to prevent cyanosis. To study the CI outcomes in patients who underwent palliative surgery with either BTSs or VPCs with flow regulatory clips. This single-center retrospective study evaluated demographic characteristics and interventional outcomes of 49 consecutive pediatric patients who required CI for BTS (BTS group) or VPC (VPC group) between January 2008 and September 2018. Overall, 34 and 18 procedures were performed in the BTS and VPC groups, respectively. Moreover, 19/32 (59.3%) and 12/17 (70.1%) patients from the BTS and VPC groups had flow regulatory clips, respectively. All clips were unclipped successfully; one patient in each group underwent staged unclipping. A higher proportion of "clipped patients" underwent CI due to desaturation [clipped vs. non-clipped: BTS, 10/20 (50.0%) vs. 3/14 (21.4%), p = 0.092; VPC, 9/13 (69.2%) vs. 1/5 (20.0%), p = 0.060]. Most clipped patients successfully progressed to the next stage [BTS, 19/20 (95.0%); VPC, 12/13 (92.3%)]. Severe adverse events (SAEs) were more frequent in the VPC group than in the BTS group [3/13 (23.1%) vs. 0/20 (0%), p = 0.024]. Two patients developed an atrioventricular block (requiring an atropine infusion), while one died due to pulmonary overcirculation. While the indication of CI was cyanosis for a higher proportion of clipped patients, all clips were unclipped successfully. The incidence of CI-related SAEs was higher in the VPC group than in the BTS group.

Simplified primum ASD closure technique in complete VSD repair: shallow suture crossing on the AV node.

The primum atrial septal defect suture line adjacent to the crux is performed carefully with various techniques to avoid atrioventricular block in repair of complete atrioventricular septal defect. We describe our technical modification to simplify the shallow suture line only into the endocardium above the atrioventricular node without conduction disturbance.

The Ventricular Hypokinesis at the Apical Pacing Site due to the Early Shortening and Rebound Stretch in a Case with Fontan Procedure.

The left ventricular (LV) apex is recommended as the first choice for positioning the epicardial pacing. We encountered a patient with congenital heart disease (CHD) showing hypokinesis of the LV apical pacing site after implantation of a pacemaker with epicardial leads. This phenomenon was revealed by the early shortening and systolic rebound stretch of the same lesion on two-dimensional speckle tracking echocardiography, which developed in the intraventricular dyssynchrony between the LV apex and base. Cardiac resynchronization therapy provided an excellent result around the hypokinetic lesion. It is wise to arrange detailed evaluations in each patient with complicated CHD, aiming at a successful treatment to enable ventricular synchronicity.

[Current Surgical Treatment for Patients with Hypoplastic Left Heart Syndrome, from the Viewpoint of Emergent Operation].

The treatment of hypoplastic left heart syndrome has improved dramatically with the development of treatment strategies due to improved understanding of hemodynamics, improved surgical methods, and the widespread use of fetal diagnosis. However, cases of early closure of the foramen ovale require emergency surgery immediately after birth, and further improvement of treatment results is needed. The right ventricular pulmonary artery shunt reported from Japan is well known worldwide and has greatly contributed to improved outcomes up to six months after the Norwood procedure. Also contributing to the improved results of the Norwood procedure is the widespread use of bilateral pulmonary artery banding to avoid palliative open heart surgery in the neonatal period. Although this method is widely used in Japan, there is still room for improvement in such areas as postoperative left pulmonary artery stenosis and aortic arch reconstruction after stenting of the ductus arteriosus. Now that the results of the Norwood procedure have stabilized, there is a need to improve treatment methods to establish a better Fontan circulation in the future.

Risk factors for mortality after cardiovascular surgery in patients with functional single ventricle and right isomerism.

OBJECTIVES: Cardiac malformations are a major component of heterotaxy syndrome that results in significant mortality and morbidity, especially in patients with a single ventricle and right isomerism (RI). The goal of this study was to evaluate the mortality after cardiovascular surgery in patients with a functional single ventricle and RI over a long follow-up period (∼40 years) and to determine the predicted risk factors for mortality. METHODS: We performed a retrospective review of the medical records of 129 consecutive patients with functional single ventricle and RI who underwent pulmonary flow control operations at Mt. Fuji Shizuoka Children's Hospital between 1979 and 2020. To evaluate mortality rates, the patients were divided into 2 groups (era 1: 1979-1999 and era 2: 2000-2020) based on the date of the first-stage palliation. RESULTS: The estimated survival rate at 10 years was 36.4% in era 1 and 57.8% in era 2. The estimated survival rate improved significantly (P = 0.0268) between the 2 eras. The rate of Fontan procedure completion was also significantly better in the current era (P = 0.0392; 22/59 in era 1 and 38/66 in era 2). In the multivariable analysis, the date of the first-stage palliation was the only predictor of mortality. CONCLUSIONS: The mortality rate after cardiovascular surgery in patients with a functional single ventricle and RI has improved over the past 20 years; however, it still remains high. This improvement may be attributed to our current surgical strategy and clinical management; however, further investigations are needed to prove this observation.

Pulmonary atresia with intact ventricular septum in the setting of D-transposition of the great arteries associated with hypoplastic left ventricle and severe mitral regurgitation.

We report the first successful Glenn procedure for pulmonary atresia with intact ventricular septum in the setting of D-transposition of the great arteries. This case was complicated by hypoplastic left ventricle and severe mitral regurgitation. Partial closure of the mitral valve at the time of Blalock-Taussig shunting resulted in improvement of heart failure.

Primary central pulmonary artery plasty for right atrial isomerism with pulmonary coarctation.

OBJECTIVE: Patients with unbalanced pulmonary artery growth resulting from pulmonary coarctation are considered unsuitable candidates for the Fontan procedure. Particularly, patients with right isomerism pose a challenge. We aimed to investigate the use of primary central pulmonary artery plasty at initial palliation in patients with right isomerism. METHODS: We recruited 34 right isomerism patients with pulmonary atresia and pulmonary coarctation who underwent modified Blalock-Taussig shunt with or without primary central pulmonary artery plasty between 1998 and 2014. We classified them into the primary central pulmonary artery plasty (group P) and no primary central pulmonary artery plasty (group N) groups. We retrospectively analyzed reintervention for pulmonary artery after initial palliation, difference in size between the left and right pulmonary arteries, overall survival, success of the Fontan procedure. RESULTS: The group P and group N included 25 and 9 patients, respectively. Five (20%) and six (67%) patients in group P and group N, respectively, required reintervention for pulmonary artery after initial palliation (p = 0.017). No patient underwent reintervention for the pulmonary artery before bidirectional cavopulmonary shunt in group P. There was a significant difference in the bilateral pulmonary artery size balance between the groups before bidirectional cavopulmonary shunt (p = 0.041). The two-lung Fontan procedure was successful in 14 (56%) and 1 (11%) patient in group P and group N. CONCLUSION: Primary central pulmonary artery plasty may contribute toward improving the balance in the size of the PA and preclude the need for reintervention for PA.

Open-sleeve technique: A new approach for aortic valve leaflet reconstruction in small children.

A boy was diagnosed with a unicuspid aortic valve with severe stenosis at birth. Percutaneous balloon aortic valvuloplasty was performed four times; however, he had severe heart and growth failure. Thus, aortic valve repair was performed at age 2 years and 6 months. He weighed 6.6 kg. The aortic valve annulus diameter was 9.8 mm (z value = 0.43). We report on a small toddler with congenital aortic stenosis who was successfully treated with autologous pericardial aortic valve leaflet reconstruction using the open-sleeve technique.

Truncal valve leaflet reconstruction with autologous pericardium in a neonate.

A boy diagnosed with persistent truncus arteriosus and severe truncal valve regurgitation had uncontrollable heart failure. Thus, truncal valve repair, ventricular septal defect closure, and right ventricular outflow tract reconstruction were performed on the second day of life. We report about a neonate with severe truncal valve regurgitation who was successfully treated with autologous pericardial truncal valve leaflet reconstruction.

[Fontan Procedure in Hypoplastic Left Heart Syndrome:for Better Establishment of Fontan Circulation].

Recently, the number of patients with hypoplastic left heart syndrome reaching the final stage of Fontan operation is increasing due to the systematization of staged therapies including bilateral pulmonary artery banding. However, in case, the systemic and pulmonary circulatory pathways initially formed by the Norwood procedure are not always sufficient to obtain a good Fontan circulation. In particular, depending on the method of reconstruction of the aortic arch, aortic re-coarctation may result in increased ventricular afterload. Furthermore, inadequate aortopulmonary space causes pulmonary artery stenosis, which increases the resistance of the pulmonary artery. In addition, tricuspid regurgitation and increased collateral circulation due to the synergistic effects of multiple reoperations and cyanosis can worsen cardiac function due to increased volume load and further increase pulmonary vascular resistance, preventing the establishment of a good Fontan circulation. In order to resolve these factors before Fontan operation and establish a better Fontan circulation, it is important to develop a comprehensive treatment strategy as well as a step-by-step surgical treatment strategy.

Outcomes of primary sternal closure for postoperative mediastinitis in children.

OBJECTIVES: We retrospectively analysed outcomes of debridement and primary sternal closure for postoperative mediastinitis in children. METHODS: Between January 2007 and July 2019, 1285 patients under the age of 20 years underwent congenital heart surgery at the Iwate Medical University. Of these, 22 children had postoperative mediastinitis (1.7%). We performed adequate debridement and primary sternal closure with pectoralis major muscle advancement flaps. We evaluated hospital survival rates, reintervention, duration of intravenous antibiotic treatment, intensive care unit (ICU) stay and hospital stay. RESULTS: The median age and weight at surgery were 12.5 months (range 0-228 months) and 7.8 kg (range 2.2-64.2 kg), respectively. Two patients (9%) had a history of delayed sternal closure. Staphylococcus was the most common causative agent for infection (82%). All cases were categorized as Robicsek's classification type II mediastinitis. The hospital survival rate was 95%, and freedom from reintervention for infectious complications was observed in 91% of the patients. The median durations of intravenous antibiotic treatment, ICU stay and hospital stay were 18 days (range 9-46 days), 4 days (range 1-87 days) and 22.5 days (range 11-87 days). The median follow-up time was 89 months (range 2-148 months), and there was no evidence of recurrent mediastinitis, musculoskeletal growth, physical deformity, breast development and upper trunk or limb movement. CONCLUSIONS: Primary sternal closure is an effective procedure for children as it can significantly shorten treatment duration and reduce physical and psychological burdens. Its results compare favourably with those of conventional therapy in terms of mortality and complications.

Fatal septic embolism due to Staphylococcus lugdunensis-induced bacteremia.

Staphylococcus lugdunensis infective endocarditis (IE) is very rare in children. A female neonote presented with fever on the 29th postoperative day after undergoing a modified Norwood procedure (right ventricular-pulmonary artery [RV-PA] conduit). Blood cultures were positive for S. lugdunensis. Echocardiography did not demonstrate vegetation. Therefore, we made a diagnosis of catheter-related bacteremia instead of IE. Cultures were negative 3 days after treatment initiation with intravenous vancomycin. One month after discharge, she developed acute hypoxia and could not be revived because of obstruction of RV-PA conduit with large vegetation. Even in S. lugdunensis bacteremia without IE, surgical treatment should be considered early.

Adult case of tetralogy of Fallot associated with atrioventricular septal defect.

The patient was a 28-year-old woman who was misdiagnosed with tetralogy of Fallot and straddling mitral valve after birth. She underwent a left modified Blalock-Taussig shunt at the age of 1 year. At age 28, she presented with fatigue and progressive cyanosis. Finally, she was diagnosed with tetralogy of Fallot and complete atrioventricular septal defect. To measure the exact biventricular volumes, we performed cardiac magnetic resonance imaging in addition to cardiac angiography and ensured adequate volume capacity. We eventually decided to perform biventricular repair. Her postoperative course was uneventful, and she returned to full-time work.

Intra-Extracardiac Total Cavopulmonary Connection for Patients With Anatomical Complexity.

BACKGROUND: Currently, the extracardiac conduit total cavopulmonary connection (eTCPC) is the most widely used for Fontan modification worldwide. Nevertheless, there have been some cases that are difficult for performing eTCPC because of their anatomical complexity, such as apicocaval juxtaposition. For such cases, in 2002, we introduced the intra-extracardiac TCPC (ieTCPC). METHODS: We reviewed our 20-year single-center experience with 316 TCPC patients to compare eTCPC (n = 277) and ieTCPC (n = 39) in terms of mortality and morbidity. ieTCPC was indicated for the cases in which there was concern that the TCPC conduit would be too curved for ordinary eTCPC. RESULTS: Early death occurred in 1 patient and late death occurred in 15 patients. The actuarial survival rate in the eTCPC and the ieTCPC groups at 10 years were 95.1% and 100.0%, respectively. There was no significant difference in actuarial survival between eTCPC and ieTCPC patients. In the multivariate analysis, preoperative superior vena cava pressure and preoperative oxygen saturation were found to be the independent predictor for postoperative mortality. There was also no significant difference in actuarial rate of freedom from late-occurring complications between eTCPC and ieTCPC groups. In the multivariate analysis, dominant right ventricle and preoperative SVC pressure were independent predictors for late-occurring complications. CONCLUSIONS: The clinical outcomes in patients who undergo eTCPC and ieTCPC appear to be excellent, with low mortality and morbidity rates in the midterm. ieTCPC may be a good option for TCPC cases with anatomical complexity such as apicocaval juxtaposition and separated hepatic vein drainage.

[Surgical Strategy for Pulmonary Atresia with Ventricular Septal Defect with Major Aortopulmonary Collateral Artery].

Although the characteristics and pathophysiology of major aortopulmonary collateral artery (MAPCA) have been better understood, treatment of pulmonary atresia and ventricular septal defect with MAPCA remains challenging. The difficulty in treating this disease is the lack of availability of pulmonary homografts required for pulmonary angioplasty in Japan and the need for manipulation of the posterior mediastinum region, which is not performed in normal cardiac surgery. It is important to build an appropriate surgical strategy by means of preoperative computed tomography( CT) and selective angiography. For treatment, unifocalization or rehabilitation is selected depending on the condition of MAPCA and central pulmonary artery. Because unifocalization is highly invasive, it would be performed at 6 months of age and weigh 5 kg. As a procedure, extensive dissection is performed, and anastomoses between tissue to tissue are basically performed, and reconstruction of the right ventricular outflow tract is performed using a valved conduit that can secure anterograde pulmonary blood flow that is not affected by the condition of the lung. It is effective to confirm postoperative lung perfusion scan and CT, perform a cardiac catheterization test approximately 6 months after surgery, and maintain the pulmonary vessels with catheter intervention if necessary. The ultimate goal of treating this disease is not only to improve cyanosis, but also to maintain pulmonary circulation at lower right ventricular pressure.