Lymphoscintigraphy Findings are Associated with Outcome in Children with Chylothorax After Cardiac Surgery.

Postoperative chylothorax in patients with congenital heart diseases (CHD) results in poor outcomes if anatomical and functional abnormalities of the lymphatic system are present. While these abnormalities are typically diagnosed by intranodal lymphangiography and dynamic contrast magnetic resonance lymphangiography, the usefulness of lymphoscintigraphy in these patients has not been evaluated. Between January 2019 and December 2021, 28 lymphoscintigraphies were performed in our institution for investigating prolonged pleural effusion after cardiac surgery. The images were assessed by three board-certified pediatric cardiologists retrospectively to determine the likelihood of a central lymphatic flow disorder. The likelihood was scored (range 1-3) based on structural abnormalities and congestive flow in the lymphatic system. Those scores were summed and the likelihood was categorized as low to intermediate (< 8 points) or high (8 or 9 points). Median age at lymphoscintigraphy was 129 days (IQR, 41-412 days), it was performed at a median of 22 days (IQR, 17-43) after surgery, and median score was 6 points (IQR, 4-7.5). Kendall's coefficient of concordance (0.867; p < 0.05) indicated high inter-rater reliability. Overall survival at 6 months after surgery was 92.5% in the low-to-intermediate group but 68.6% in the high group (p < 0.05), and duration of postoperative thoracic drainage was 27 and 58 days, respectively (p < 0.05). Lymphatic abnormalities detected by lymphoscintigraphy were associated with poorer outcomes. Lymphoscintigraphy was thought to be useful in assessing anatomic and functional lymphatic abnormalities, despite its minimal invasiveness.

Case Report: Retroaortic Innominate Vein With Supracardiac Total Anomalous Pulmonary Venous Connection.

A retroaortic innominate vein (RAIV) is a rare anomaly that passes posterior to the ascending aorta to join the superior vena cava and is associated with congenital heart disease (CHD). The RAIV and normal left innominate vein (LIV) rarely duplicate. The etiology of the RAIV and its relationship with CHD remains unknown. We report a case involving a 1-month-old baby girl with RAIV and supracardiac total anomalous pulmonary venous connection (TAPVC). Transthoracic echocardiogram demonstrated a pulmonary venous confluence (CPV) posterior to the left atrium, an abnormal vertical vein (VV) that originated from the CPV, and a normally positioned LIV. Three-dimensional cardiac computed tomography revealed the VV and RAIV to which it merged. This is the first reported case of a combination of RAIV and isolated TAPVC. We speculate that the VV is connected to the CPV during fetal life, thus leaving the RAIV behind. The RAIV may be detected in various forms with the development of new diagnostic imaging methods. Although a RAIV itself does not require treatment, establishing a correct diagnosis before invasive tests and procedures are performed can help prevent unexpected complications.

The Impact of the Pulmonary Artery Index and Aortopulmonary Collateral Artery Coil Embolization on Intractable Pleural Effusions After a Fontan Surgery.

An intractable pleural effusion is a common comorbidity of a Fontan operation, occasionally leading to undesirable outcomes. The preventive effect of aortopulmonary collateral (APC) coil embolization against a pleural effusion before a Fontan operation is still controversial.This is a retrospective single-center study; among 227 Fontan cases, 57 cases with complete MRI data were analyzed at first. Factors associated with the duration of pleural drainage (median: 6 (2-41) days) and that of postoperative hospital stay (median: 25 (14-91) days) were analyzed using a multiple regression analysis. The pulmonary artery index (PAI; Nakata index) was associated with both the pleural drainage duration (P < 0.05, r2 = 0.17) and postoperative hospital stay (P < 0.05, r2 = 0.10).Thereafter, all the 227 patients were classified into the following three groups: Group A (12 patients in whom the embolization was performed within 30 days before the Fontan surgery), Group B (131 patients in whom the embolization was performed more than 30 days before the Fontan surgery), and Group C (84 patients in whom the embolization was not performed). Patients in Group A were found to be associated with the shortest length of both periods (P < 0.05).Lower PAI values were related to a prolonged pleural drainage duration and postoperative hospital stay. APC coil embolizations may reduce the risk if they are performed shortly (less than 30 days) before the operation.

Pulmonary vasodilators can lead to various complications in pulmonary "arterial" hypertension associated with congenital heart disease.

Congenital heart disease-associated pulmonary arterial hypertension (CHD-PAH) is one of the major complications in patients with CHD. A timely closure of the left-to-right shunt will generally result in the normalization of the pulmonary hemodynamics, but a few patients have severe prognosis in their early childhood. We hypothesized that wide-ranging pathological mechanism in PAH could elucidate the clinical state of severe CHD-PAH. Using electronic medical records, we retrospectively analyzed six infants with severe CHD-PAH who had treatment-resistant PH. All patients were born with congenital malformation syndrome. After starting on a pulmonary vasodilator, five of the six patients developed complications including pulmonary edema and interstitial lung disease (ILD), and four patients had alveolar hemorrhage. After steroid therapy, the clinical condition improved in four patients, but two patients died. The autopsy findings in one of the deceased patients indicated the presence of recurrent alveolar hemorrhage, pulmonary venous hypertension, ILD, and PAH. Based on the clinical course of these CHD-PAH in patients and the literature, CHD-PAH can occur with pulmonary vascular obstructive disease (PVOD)/pulmonary capillary hemangiomatosis (PCH), ILD, and/or alveolar hemorrhage. The severity of CHD-PAH may depend on a genetic disorder, respiratory infection, and upper airway stenosis. Additionally, pulmonary vasodilators may be involved in the development of PVOD/PCH and ILD. When patients with CHD-PAH show unexpected deterioration, clinicians should consider complications associated with PVOD/PCH and/or pulmonary disease. In addition, the choice of upfront combination therapy for pediatric patients with CHD-PAH should be selected carefully.

Study design for control of HEART rate in inFant and child tachyarrhythmia with heart failure Using Landiolol (HEARTFUL): A prospective, multicenter, uncontrolled clinical trial.

BACKGROUND: Persistent tachycardia in pediatric patients after congenital heart surgery further deteriorates their hemodynamic condition, and may become fatal. Therefore, immediate control of the tachycardia is mandatory in these patients. For this purpose, quick-acting, short-acting, titratable intravenous agents are required. However, there are no agents with such characteristics among the drugs approved for control of pediatric arrhythmias in Japan, and thus novel and effective medications for these patients are awaited. Landiolol, an ultrashort-acting ß-blocker, was approved in 2013 for tachyarrhythmias in adult patients with heart failure. However, its efficacy and safety in pediatric patients remain unclear. The aim of this prospective, multicenter, open-label phase IIb/III study is to investigate the efficacy and safety of landiolol in pediatric patients with tachyarrhythmias as well as heart failure. METHODS: Eligible patients are aged ≥ 3 months and <15 years, and have tachyarrhythmia (atrial fibrillation, atrial flutter, supraventricular tachycardia) as well as heart failure. The primary endpoint of the study is ≥20% reduction from baseline heart rate or return to normal sinus rhythm within 2h after starting intravenous administration of landiolol. Patients will receive intravenous infusion of landiolol, starting at 1µg/kg/min. The dose will be increased by 1µg/kg/min every 15-20min until the tachycardia rate has decreased by >20% or tachycardia has terminated, and the dose will then be maintained or further increased depending on the patient's condition. The study was started in April 2015 and will end within a few years. CONCLUSIONS: The study was designed and designated the "HEARTFUL study" in the hope of establishing a basis for control of HEART rate in inFant and child tachyarrhythmia Using Landiolol in children with heart failure.

Results of extracardiac conduit total cavopulmonary connection in 500 patients.

OBJECTIVES: This single-institution study aimed to evaluate the early to mid-term outcomes of extracardiac conduit total cavopulmonary connection (EC-TCPC). METHODS: Between March 1994 and March 2014, 500 patients (median age, 3.4 years) underwent EC-TCPC at our hospital. One hundred and twenty-three patients (24.6%) showed heterotaxy, and fenestration was created in 6 patients (1.2%). The standard institutional treatment policy included postoperative anticoagulation and individualized cardiovascular medication. The mortality and morbidity rates, haemodynamic status, cardiopulmonary exercise capacity and liver examination results during the follow-up period (median, 6.7 years) were retrospectively reviewed. RESULTS: There were 2 early and 17 late deaths. The Kaplan-Meier estimated survival rate was 96.2% at 10 years and 92.8% at 15 years. Bradyarrhythmia and tachyarrhythmia occurred in 19 and 13 patients, respectively. Other late-occurring morbidities included protein-losing enteropathy in 8, thromboembolism in 5, bleeding complications in 6 and liver cirrhosis in 1 patient. The rate of freedom from late-occurring morbidities was 82.1% at 15 years. In the multivariate analysis, heterotaxy was found to be a predictor for mortality (P = 0.02), whereas age at operation was a predictor for new-onset arrhythmias (P = 0.048). In the cardiopulmonary exercise test (n = 312), the peak VO2 was 84.9 ± 17.3% of the predicted value, which tended to decrease with age (R(2) = 0.32) and elapsed time since operation (R(2) = 0.21). Postoperative cardiac catheterization (n = 468; time from surgery, 3.6 ± 4.3 years) showed central venous pressure of 9.9 ± 2.4 mmHg, ventricular end-diastolic pressure of 5.2 ± 3.3 mmHg, cardiac index of 3.4 ± 0.8 l/min/m(2) and arterial oxygen saturation of 94.2 ± 4.8%. In 101 patients who were followed up for ≥10 years, amino-terminal type III procollagen peptide and collagen type IV levels exceeded the normal ranges in 52.9 and 75.2% of patients, respectively, and liver ultrasonography revealed hyper-echoic spots in 43.3% of patients. CONCLUSIONS: The early to mid-term outcomes of post-EC-TCPC patients managed with individualized pharmacotherapy were excellent, with low mortality and morbidity rates; however, development of late-occurring morbidities specific to Fontan physiology, including exercise intolerance and liver disease, must be carefully monitored during the long-term follow-up.

Acute rupture of chordae tendineae of the mitral valve in infants: a nationwide survey in Japan exploring a new syndrome.

BACKGROUND: Recently, infant cases of acute heart failure attributable to rupture of the mitral chordae tendineae have been reported. However, little is known about the pathogenesis and clinical course of this condition. METHODS AND RESULTS: Ninety-five children with rupture of mitral chordae tendineae were identified in nationwide surveys of Japan diagnosed from 1995 to 2013. The clinical manifestations, management strategies, and prognosis were investigated. Eighty-one (85%) patients were between 4 and 6 months (median, 5 months) of age. In 63 (66%) patients, rupture occurred during the spring or summer. The underlying conditions before rupture included Kawasaki disease (10 cases), maternally derived anti-SSA antibodies (2 cases), and infective endocarditis (1 case). Surgery was performed in 80 patients (94 operations), and the final operations included plasty of mitral chordae in 52 cases and mechanical valve replacement in 26 cases. The histopathologic examinations of the mitral valves and chordae (n=28) revealed inflammatory reactions with predominant mononuclear cell infiltration in 18 cases (64%) and increased fibrous and myxoid tissue in 11 cases (39%), suggesting that nonbacterial infectious or autoimmune endocarditis and myxoid changes are involved in the pathogenesis. Eight patients (8.4%) died before (n=6) and shortly after (n=2) the operation, and significant neurological complications persisted in 10 cases (11%). CONCLUSIONS: Acute heart failure attributable to rupture of the mitral chordae tendineae in infants is a unique disease resulting from diverse causes. This condition should be recognized as a significant cardiovascular disorder that may cause sudden onset of cardiogenic shock and death in infants.

Midterm surgical results of total cavopulmonary connection: clinical advantages of the extracardiac conduit method.

OBJECTIVE: We evaluated the midterm surgical outcomes of intra-atrial lateral tunnel and extracardiac conduit total cavopulmonary connection to clarify the clinical superiority. METHODS: Patients (n = 167) underwent total cavopulmonary connection (88 with lateral tunnel and 79 with extracardiac conduit) from November 1991 to March 1999. Survival, incidence of reoperation and late complications, exercise tolerance, hemodynamic variables, and plasma concentration of natriuretic peptide type A were compared. In the lateral tunnel group, time-related change in lateral tunnel size was investigated for its relationship to postoperative arrhythmias. RESULTS: The 8-year survival was 93.2% in the lateral tunnel group and 94.9% in the extracardiac conduit group. Seven reoperations were performed in the lateral tunnel group but none in the extracardiac conduit group. Supraventricular arrhythmias developed in 14 patients (15.9%) in the lateral tunnel group and in 4 patients (5.1%) in the extracardiac conduit group (P =.003). Freedom from cardiac-related events was 72.5% in the lateral tunnel group and 89.8% in the extracardiac conduit group at 8 years (P =.0098). Hemodynamic variables and exercise tolerance were similar in both groups but plasma natriuretic peptide type A concentration, a parameter of atrial wall tension, was higher in the lateral tunnel group. In the lateral tunnel group, intra-atrial tunnel size increased by 19.4% during the 44.2-month interval and the percent increase in tunnel size was an independent predictor of supraventricular arrhythmias. CONCLUSIONS: The midterm survival, hemodynamic variables, and exercise tolerance were similar and satisfactory in both lateral tunnel and extracardiac conduit groups; however, the incidence of cardiac-related events was significantly less frequent in the extracardiac conduit group. In the lateral tunnel group, careful observation is required to monitor the relationship of the dilating tendency of the intra-atrial tunnel and the development of late complications.

Left atrial appendage aneurysm in a child.

We report a case of left atrial appendage aneurysm in a 1-year-old child. The patient was asymptomatic, and a mediastinal liquid mass that was confirmed to be an aneurysm of the left atrial appendage was incidentally revealed by transthoracic echocardiography. Aneurysmectomy was performed during cardioplegic arrest under the support of cardiopulmonary bypass. The postoperative course was uneventful.