Probiotics may alleviate intestinal damage induced by cardiopulmonary bypass in children.

OBJECTIVES: Intestinal ischaemia-reperfusion injury induced by cardiopulmonary bypass causes intestinal epithelial barrier dysfunction, leading to dysbiosis and bacterial translocation. We conducted a randomized prospective study with 2 objectives: (i) to investigate epithelial barrier dysfunction and bacterial translocation induced by cardiopulmonary bypass and changes in the gut microbiota and (ii) to verify whether probiotics can improve these conditions. METHODS: Between 2019 and 2020, patients 0-15 years old scheduled to undergo cardiac surgery using cardiopulmonary bypass were enrolled and randomly allocated to 2 groups: the intervention group received probiotics and the control group did not receive probiotics. We analysed the microbiota in faeces and blood, organic acid concentrations in faeces, plasma intestinal fatty acid-binding protein and immunological responses. RESULTS: Eighty-two patients were enrolled in this study. The characteristics of the patients were similar in both groups. The total number of obligate anaerobes was higher in the intervention group than in the control group after postoperative day 7. We identified 4 clusters within the perioperative gut microbiota, and cluster changes showed a corrective effect of probiotics on dysbiosis after postoperative day 7. Organic acid concentrations in faeces, incidence of bacterial translocation, intestinal fatty acid-binding protein levels and immunological responses, except for interleukin -17A, were not markedly different between the 2 groups. CONCLUSIONS: Administration of probiotics was able to correct dysbiosis but did not sufficiently alleviate the intestinal damage induced by cardiopulmonary bypass. More effective methods should be examined to prevent disturbances induced by cardiac surgery using cardiopulmonary bypass. CLINICAL TRIAL REGISTRATION NUMBER: https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000037174 UMIN000035556.

Diagnosis of Carney complex following multiple recurrent cardiac myxomas.

Carney complex is a rare syndrome caused by a genetic mutation leading to multiple endocrine abnormalities and a variety of tumors. Here, we report a case of Carney complex diagnosed due to recurrent multiple myxomas in the right atrium of a patient 16 years after the resection of the primary left atrial myxoma. Surgical excision was performed for the multiple recurrent right atrial tumors under cardiopulmonary bypass. The patient remained complication-free after surgery and was discharged on the 14th day. He was scheduled to continue echocardiographic follow-up and periodic systemic review by an endocrinologist. This case emphasizes the fact that if cardiac myxomas tend to be multiple and recurrent at a relatively young age, the possibility of Carney complex should be considered, even in the absence of any other related feature other than cardiac tumors.

Application of the Konno procedure for infective endocarditis in native bicuspid aortic valve with annular abscess extending into the interventricular septum.

Annular abscess is a serious complication of infective endocarditis, which often requires complex surgery and has a very high post-operative mortality rate. The Konno procedure involves valve annuloplasty for a narrow aortic annulus or left ventricular outflow tract stenosis in children; it is also performed for various cardiac conditions in adults. Here, we report a case of the Konno procedure performed in a patient with aortic valve infective endocarditis, with an annular abscess extending into the interventricular septum (IVS). A 58-year-old man who presented to our hospital with fever was diagnosed with aortic valve infective endocarditis caused by Streptococcus saccharolyticus. On echocardiography, an annular abscess in the direction of the IVS was detected, and surgery was planned. The Konno procedure was performed to secure an adequate surgical field and to debride and reconstruct the cavity created by the interventricular septal abscess. The patient was discharged uneventfully 29 days after surgery.

Iatrogenic diversion of the inferior vena cava into the left atrium diagnosed 43 years after surgical atrial septal defect closure.

The diversion of the inferior vena cava into the left atrium after surgical atrial septal defect closure is a fatal complication. Cases of atrial septal defect with no inferior rim should be treated with this complication in mind.

Surgical repair of a right coronary aneurysm with a coronary artery fistula to the right atrium.

A coronary artery fistula is a rare condition caused by abnormal coronary artery embryological development. Although most cases are asymptomatic, in some, the large shunt volume and the myocardial ischemia due to the steal phenomenon require surgical treatment. We present the case of a 40-year-old woman who presented with angina on exertion. Enhanced computed tomography showed a giant right coronary artery (RCA) aneurysm with an RCA-to-right atrium fistula. Because of the presence of symptoms and the presence of large fistulous tract, the patient was considered a surgical candidate. The procedure was performed under cardiopulmonary bypass. Ligation and closure of the fistula were performed in combination with dissection of the enlarged main trunk of the RCA and coronary artery bypass using the internal thoracic artery because of its potential for long-term patency. The postoperative course was uneventful.

Concomitant septal myectomy and mitral valve repair in a child with Noonan syndrome.

We successfully performed concomitant septal myectomy and mitral valve repair in a child with Noonan syndrome.

Congenital vascular ring.

A vascular ring is a rare congenital cardiovascular anomaly, which encircles and compresses the trachea or esophagus, or both. In this review we discuss the pathophysiology, theoretical embryopathogenesis, diagnostic modalities, and surgical treatment of the different types of vascular ring. Knowledge of the normal embryonic development of the aortic arch and related structures is important for understanding and classifying the various forms of vascular ring. The development of a vascular ring begins with the embryonic aortic arch system. The persistence, involution, or regression of the arches determines the multiple variations of vascular ring. With the development of new technologies, multi-detector computed tomography (MDCT) has become a good diagnostic modality for pre- and postoperative evaluation. MDCT provides an excellent image of aortic arch abnormalities and the related anatomy, as well as the tracheal pathology. For patients with symptoms, surgical division of the vascular ring usually achieves excellent outcomes with marked resolution of symptoms and a low risk of morbidity and mortality. Symptomatic vascular rings require early surgical intervention to prevent prolonged vascular compression of the airway and serious complications.

[Redo Right Ventricular Outflow Tract Reconstruction in Adult Patients with Congenital Heart Disease].

Between April 2005 and February 2019, 11 adult patients underwent redo reconstruction of the right ventricular outflow tract. The primary malformation was Fallot's tetralogy in 8, transposition of the great arteries in 2, and pulmonary atresia with intact ventricular septum in 1. Mean age at redo operation was 27.4 years. Right ventricular outflow tract was reconstructed with expanded polytetrafluoroethylene conduits with bulging sinuses and a fan-shaped valve in 9, transannular patch in 1, and right ventricular outflow patch in 1. There were no early and late deaths. One patient had residual branch pulmonary stenosis, while other 10 patients had no significant pulmonary stenosis and no significant pulmonary regurgitation. Signs and symptoms were improved in these 10 patients. Re-operation should be done before the development of right ventricular dysfunction, while it can be performed with satisfactory results in adult patients.

Systemic Atrioventricular Valve Replacement in Patients With Functional Single Ventricle.

To review the outcome after atrioventricular valve replacement in single ventricle patients. The medical records of 37 consecutive patients who underwent initial valve replacement between 2001 and 2016 were reviewed. Actuarial survival rates were 73%, 65%, and 59% at 1, 5, and 10 years, respectively. Multivariate analysis indicated body surface area <0.28 m2 (P = 0.007; hazard ratio, 31.1), preoperative inotropic support (P < 0.001; hazard ratio, 24.5), primary valve replacement (P = 0.044; hazard ratio, 6.1), oversized prosthesis (P = 0.001; hazard ratio, 14.5), and intra- or postoperative extracorporeal membrane oxygenation support (P < 0.001; hazard ratio, 53.2) were the risk factors for mortality. Cumulative incidences of redo replacement were 11%, 17%, and 17% at 1, 5, and 10 years, respectively. There was no risk factor for redo replacement. Among 11 patients undergoing valve replacement before or at the time of bidirectional cavopulmonary shunt, all 4 patients who reached Fontan completion survived. Among 13 patients undergoing valve replacement after bidirectional cavopulmonary shunt, only 3 patients reached Fontan completion. Among 11 patients undergoing valve replacement after Fontan completion, there were 3 operative mortalities and 2 late mortalities. For 7 of 8 hospital survivors, cardiac index improved from 2.2 L/min/m2 (interquartile range, 2.0-2.4) to 3.4 (2.8-3.7) (P = 0.002). Atrioventricular valve replacement was a reasonable choice of treatment for single ventricle patients. For small patients with impaired ventricular function who had no choice other than valve replacement, commercially available valves were oversized and outcomes remained poor.

Utility of a super-flexible three-dimensional printed heart model in congenital heart surgery.

OBJECTIVES: The objective of this study was to assess the utility of 3D printed heart models of congenital heart disease for preoperative surgical simulation. METHODS: Twenty patient-specific 3D models were created between March 2015 and August 2017. All operations were performed by a young consultant surgeon who had no prior experience with complex biventricular repair. All 15 patients with balanced ventricles had outflow tract malformations (double-outlet right ventricle in 7 patients, congenitally corrected transposition of great arteries in 5, transposition of great arteries in 1, interrupted aortic arch Type B in 1, tetralogy of Fallot with pulmonary atresia and major aortopulmonary collateral arteries in 1). One patient had hypoplastic left heart complex, and the remaining 4 patients had a functional single ventricle. The median age at operation was 1.4 (range 0.1-5.9) years. Based on a multislice computed tomography data set, the 3D models were made of polyurethane resins using stereolithography as the printing technology and vacuum casting as the manufacturing method. RESULTS: All but 4 patients with a functional single ventricle underwent complete biventricular repair. The median cardiopulmonary bypass time and aortic cross-clamp time were 345 (110-570) min and 114 (35-293) min, respectively. During the median follow-up period of 1.3 (0.1-2.5) years, no mortality was observed. None of the patients experienced surgical heart block or systemic ventricular outflow tract obstruction. CONCLUSIONS: Three-dimensional printed heart models showed potential utility, especially in understanding the relationship between intraventricular communications and great vessels, as well as in simulation for creating intracardiac pathways.

Application of hybrid Stage I palliation for patients with two ventricular cavities and hypoplastic left heart structures.

OBJECTIVES: To assess the feasibility of hybrid Stage I palliation consisting of bilateral pulmonary artery bandings and ductal stenting for patients with 2 ventricular cavities and hypoplastic left heart structures. METHODS: Eleven consecutive patients who underwent hybrid Stage I palliation between 2010 and 2017 were enrolled. The diagnoses were interrupted aortic arch/coarctation of the aorta, ventricular septal defect and significant left ventricular (LV) outflow tract obstruction in 5 patients, critical aortic stenosis and reduced LV contraction in 3 patients and hypoplastic left heart complex in 3 patients. RESULTS: The median age at definitive surgery was 12 months (range 6-22 months). During the mean follow-up period of 24 months (range 9-83 months) following the definitive surgery, there was 1 death. Two patients with interrupted aortic arch/coarctation of the aorta did not undergo the Yasui operation but underwent arch repair and ventricular septal defect closure after the growth of the aortic valve and LV outflow tract. For 2 of the 3 patients with critical aortic stenosis, biventricular repair was performed. Of the 3 patients with hypoplastic left heart complex, 2 patients showed growth of the mitral valve and left ventricle following LV rehabilitation by balloon pulmonary artery dilatation or surgical debanding of the banded pulmonary arteries and subsequently underwent biventricular repair, which resulted in 1 death. CONCLUSIONS: Hybrid Stage I palliation would be a safe and beneficial treatment for patients with 2 ventricles, as a bridge to decide whether and how to achieve a biventricular repair and whether it should be preceded by a preliminary LV rehabilitation.

Neonatal repair of left atrial diverticulum with gigantic thrombus without cardiopulmonary bypass.

A 5-day-old neonate with coarctation of the aorta, hypoplastic aortic arch, large apical muscular ventricular septal defect, and patent ductus arteriosus developed pulmonary over-circulation and systemic hypoperfusion underwent bilateral pulmonary artery banding through median sternotomy as a part of hybrid stage I palliation. At operation, left atrial diverticulum with gigantic thrombus formation at the base of the left atrial appendage was incidentally detected by intraoperative direct echocardiography, and therefore, was successfully resected with the whole thrombus inside it without use of cardiopulmonary bypass. Histopathological finding was compatible with diverticulum. The patient was free from atrial arrhythmia and recurrent thrombus formation.

Can Fontan Conversion for Patients Without Late Fontan Complications be Justified?

BACKGROUND: Fontan conversion from a classic Fontan operation such as atriopulmonary connection to total cavopulmonary connection with antiarrhythmia surgery is currently not indicated for patients without any late Fontan complications. METHODS: Thirty-two consecutive patients who underwent Fontan conversion between 1991 and 2012 were divided into 2 groups by the presence (group 1: n = 25, atrial tachyarrhythmia [AT] in 24 and protein-losing enteropathy in 4) or absence (group 2: n = 7) of late Fontan complications, and the surgical outcomes were retrospectively compared. During the study period, heart transplantation was not indicated for patients with failed Fontan circulation in Japan. RESULTS: The mean follow-up period was 6.2 ± 3.7 years in group 1 and 4.6 ± 3.8 years in group 2 (p = 0.29). Overall survival rate at 10 years after conversion was 71% in group 1 and 100% in group 2 (p = 0.12). Whereas preoperative AT and protein-losing enteropathy remained after conversion in 8 patients (33%) and all 4 patients (100%), respectively, in group 1, neither were observed in group 2. Cardiac catheter examinations presurgery (n = 32) at 1 year (n = 28), and at 5 years (n = 19) after the conversion showed that the cardiac index significantly and similarly improved in both groups after the conversion, and maintained for at least 5 years. CONCLUSIONS: Cardiac output similarly improved after Fontan conversion in patients with or without late Fontan complications by elimination of venous blood congestion on Fontan pathways. Although long-term follow-up is mandatory, newly onset AT was not observed after prophylactic Fontan conversion.

Efficacy of "Awake ECMO" for critical respiratory failure after pediatric open-heart surgery.

A 4-year-old boy with atrioventricular discordance, double-outlet right ventricle, pulmonary stenosis, and mitral regurgitation, was undergoing anatomical repair consisting of Senning, Rastelli, Damus-Kaye-Stansel procedures, and a mitral valve repair, complained of post-operative excessive airway tract secretion, which ultimately developed into acute respiratory distress syndrome (ARDS) 28 days after the operation. The cause of the ARDS was thought to be frequent manual positive pressure recruitment and prolonged inhalation of pure oxygen. At 45 days after the operation, hypercapnia and respiratory acidosis turned out to be irreversible, and therefore, veno-arterial extracorporeal membrane oxygenation (ECMO) was established utilizing the Endumo(®)4000 system. Pulmonic interstitial inflammation gradually improved while resting the lung under ECMO support; however, effective ventilation volume decreased critically because a massive pulmonary hemorrhage occurred at 2 and 9 days after the initiation of ECMO. To maximize the effectiveness of respiratory physical therapy, "Awake ECMO" was started and tidal volume dramatically increased with a regained cough reflex. Five days later, he was successfully weaned off from ECMO, and discharged 7 months after the operation without any neurological and physiological sequelae.

Dopamine release via the vacuolar ATPase V0 sector c-subunit, confirmed in N18 neuroblastoma cells, results in behavioral recovery in hemiparkinsonian mice.

A 16-kDa proteolipid, mediatophore, in Torpedo electric organs mediates Ca(2+)-dependent acetylcholine release. Mediatophore is identical to the pore-forming stalk c-subunit of the V0 sector of vacuolar proton ATPase (ATP6V0C). The function of ATP6V0C in the mammalian central nervous system is not clear. Here, we report transfection of adeno-associated viral vectors harboring rat ATP6V0C into the mouse substantia nigra, in which high potassium stimulation increased overflow of endogenous dopamine (DA) measured in the striatum by in vivo microdialysis. Next, in the striatum of 6-hydroxydopamine-lesioned mice, a model of Parkinson's disease (PD), human tyrosine hydroxylase, aromatic l-amino-acid decarboxylase and guanosine triphosphate cyclohydrolase 1, together with or without ATP6V0C, were expressed in the caudoputamen for rescue. Motor performance on the accelerating rotarod test and amphetamine-induced ipsilateral rotation were improved in the rescued mice coexpressing ATP6V0C. [(3)H]DA, taken up into cultured N18 neuronal tumor cells transformed to express ATP6V0C, was released by potassium stimulation. These results indicated that ATP6V0C mediates DA release from nerve terminals in the striatum of DA neurons of normal mice and from gene-transferred striatal cells of parkinsonian mice. The results suggested that ATP6V0C may be useful as a rescue molecule in addition to DA-synthetic enzymes in the gene therapy of PD.