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.

Cardiac MRI for Fontan candidates after intrapulmonary-artery septation.

Intrapulmonary-artery septoplasty may be effective for establishing two-lung Fontan circulation in patients with unilateral pulmonary circulation. However, evaluation of the function of each lung by conventional modalities can be challenging in these patients due to differing sources of blood flow to the left and right lungs following intrapulmonary-artery septation. Herein, we report a case in which two-lung Fontan circulation was successfully achieved after using cardiac MRI along with conventional modalities to evaluate pulmonary circulation.

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.

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.

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.

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.

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.

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.

Interannular Bridge: A Novel Approach to Address Congenital Mitral Regurgitation.

A male infant with Kabuki syndrome had trivial congenital mitral regurgitation diagnosed at birth. At the age of 2 years and 9 months, the regurgitation worsened from mild to severe; thus, expedited surgical treatment was pursued. The primary operative finding was severe dysplastic two-leaflet disease. After completing chordal replacement as a conventional repair procedure, more-than-moderate central regurgitation caused by establishing a shallow coaptation between the anterior and posterior leaflets persisted. We report a successful case of mitral valve repair involving the novel option of interannular bridge for valvuloplasty to address congenital mitral regurgitation.

Impact of intrapulmonary-artery septation to pulmonary vein obstruction for two-lung Fontan.

OBJECTIVES: Patients with unbalanced pulmonary artery (PA) growth and decreased unilateral pulmonary circulation are considered unsuitable candidates for the Fontan procedure. Following our previous study on the utility of intrapulmonary-artery septation for patients with PA hypoplasia, we investigated its use in patients with pulmonary venous obstruction (PVO). METHODS: We recruited 42 patients who underwent intrapulmonary-artery septation for unilateral PA hypoplasia and/or PVO between 1998 and 2018 and classified them into no PVO or PVO group. We analysed overall survival, success of the Fontan procedure and data from catheterization and echocardiography. In PVO, we evaluated the functional lung area before the Fontan procedure and the relevance of this parameter to operative outcomes. RESULTS: The PVO and no-PVO group included 24 and 18 patients, respectively. One patient in the no-PVO and 6 patients in the PVO group died during follow-up; this difference was statistically significant (log-rank P = 0.040). In the no-PVO group, 15 (83%) patients achieved two-lung Fontan circulation. In the PVO group, 12 (50%) patients achieved two-lung Fontan circulation. Multivariate analysis revealed that functional lung area and shunt size [significantly larger in patients with functional lung area ≥50% in affected lung (P = 0.040)] were significant factors for successful two-lung Fontan procedure (P = 0.030). CONCLUSIONS: Intrapulmonary-artery septation may contribute to increase functional lung area after PVO release to establish two-lung Fontan circulation in patients with PVO who have unbalanced PA growth and/or decreased unilateral pulmonary circulation.

Complete repair with unifocalization of the only unilateral lung.

A boy with 22q11.2 deletion was diagnosed with pulmonary atresia with ventricular septal defect (PAVSD) and major aortopulmonary collateral arteries (MAPCAs). At 8 months, unifocalization of left MAPCAs and BT shunt was performed at another hospital. However, they occluded directly after surgery. An angiography revealed 2 MAPCAs supplying all segments of the right lung. Qp:Qs was 2.24. At 1 year 6 months, we performed VSD closure with unifocalization of the only right lung vascularity, using intraoperative PA flow study. We report a successful case of complete repair with unilateral lung in PAVSD and MAPCAs.

Midterm results and risk factors of functional single ventricles with extracardiac total anomalous pulmonary venous connection.

OBJECTIVES: To evaluate the clinical outcomes of surgical repair of an extracardiac total anomalous pulmonary venous connection (TAPVC) in a functional single-ventricle (f-SV) strategy. METHODS: This was a retrospective analysis of 48 consecutive cases of extracardiac TAPVC repair, from 1998 to 2015. Demographic and clinical variables were as follows: median age, 24 (range 0-744) days; median weight, 3.1 (range 2.0-9.6) kg; type of TAPVC-supracardiac, 21 patients, infracardiac, 8, and mixed, 19; right atrial isomerism, 45 patients; pulmonary atresia, 24 patients; and obstructed TAPVC, 30 patients. Concomitant procedures included systemic-to-pulmonary shunting in 15 patients, pulmonary artery banding in 12, ventricle-to-pulmonary artery shunting in 2, a Norwood procedure in one, a bidirectional Glenn procedure in 16, and a Fontan procedure in 1. RESULTS: The 1- and 5-year cumulative survival rates were 66.0% and 58.0%, respectively. Of the 28 survivors, 22 (78.6%) underwent Fontan completion and 4 (14.3%) a bidirectional Glenn procedure, and 1 (3.6%) was awaiting a bidirectional Glenn procedure. Recurrent pulmonary venous stenosis (PVS) was observed in 17 patients, with a 1- and 5-year rates of freedom from recurrent PVS 59.8% and 53.5%, respectively. Of the 20 post-operative deaths, only 4 were PVS related. Only pre-operative pulmonary atresia was identified as an independent risk factor of mortality after TAPVC repair. CONCLUSIONS: The midterm surgical outcomes of f-SV with extracardiac TAPVC were acceptable. Moreover, among survivors, Fontan completion can be sufficiently expected. Further improvement, with the development of a comprehensive treatment strategy, is required for this patient group.

Novel Left Atrioventricular Valvuloplasty for Atrioventricular Septal Defect.

An infant boy with 21 trisomy was diagnosed with complete atrioventricular septal defect-Rastelli type A with parachute left atrioventricular valve and absent left mural leaflet. Biventricular repair was difficult in infancy because the left ventricular volume and left atrioventricular valve annulus were too small. After 2 pulmonary artery bandings, the left atrioventricular valve annulus increased to 85% of normal mitral valve, and the left ventricular end-diastolic volume increased to 98% of normal. We report a successful instance of complete atrioventricular septal defect that achieved biventricular repair via novel left atrioventricular valvuloplasty for parachute left atrioventricular valve and absent left mural leaflet.

Aortic dissection in the outer third of the media: what is the role of the vasa vasorum in the triggering process?

OBJECTIVES: Extensive clinicopathological analyses of aortic dissection have implicated hypertension and genetic abnormalities as the major pathogenic mechanisms. However, previous findings from pathological examinations have often been inconsistent with these mechanisms. In this paper, we suggest a significant role for the vasa vasorum in the aetiology and pathogenesis of aortic dissection. METHODS: We reviewed records of patients who underwent thoracic aortic dissection repair at our institution between June 2008 and August 2011. Twenty-one patients (10 men, 11 women; mean age, 65.0 ± 12.0 years) underwent surgery with subsequent histopathological examination of the aortic wall. We evaluated the history and histopathological findings of these patients. RESULTS: Aortic medial changes were observed in all 21 patients. These changes included thinning and sometimes fragmentation of the elastic lamina, as well as atrophy of the smooth muscle cells, with surrounding accumulation of an Alcian blue-positive mucinous substance, mostly adjacent to the dissection. Importantly, the dissection was located in the outer third of the media in 20 of the 21 patients (95.2%). Of these 20, 18 showed histopathological evidence of sclerotic changes of the vasa vasorum, including muscular hyperplasia, elastosis, intimal fibrosis and/or luminal obstruction, and even rupture. These changes may have been secondary to hypertension or peri-aortic changes, leading to degenerative changes in the aortic media and even initiation of dissection. CONCLUSIONS: Most aortic dissections initially developed in the outer third of the media alongside the vasa vasorum. In this type of aortic dissection, dysfunction of the vasa vasorum may play a key role in long-standing ischaemia or malnutrition of the aortic media.