Clinical and Echocardiographic Impact of Tafazzin Variants on Dilated Cardiomyopathy Phenotype in Left Ventricular Non-Compaction Patients in Early Infancy.

BACKGROUND: Left ventricular non-compaction (LVNC) is a cardiomyopathy morphologically characterized by 2-layered myocardium and numerous prominent trabeculations, and is often associated with dilated cardiomyopathy (DCM). Variants in the gene encoding tafazzin (TAZ) may change mitochondrial function and cause dysfunction of many organs, but they also contribute to the DCM phenotype in LVNC, and the clinical and echocardiographic features of children with this phenotype are poorly understood. Methods and Results: We enrolled 92 DCM phenotype LVNC patients and performed next-generation sequencing to identify the genetic etiology. Ten TAZ variants were identified in 15 male patients (16.3%) of the 92 patients, including 3 novel missense substitutions. The patients with TAZ variants had a higher frequency of early onset of disease (92.3% vs. 62.3%, P=0.0182), positive family history (73.3% vs. 20.8%, P=0.0001), and higher LV posterior wall thickness Z-score (8.55±2.60 vs. 5.81±2.56, P=0.0103) than those without TAZ variants, although the mortality of both groups was similar. CONCLUSIONS: This study provides new insight into the impact of DCM phenotype LVNC and emphasizes the clinical advantages available for LVNC patients with TAZ variants.

A mutant HCN4 channel in a family with bradycardia, left bundle branch block, and left ventricular noncompaction.

We found that a female infant presenting with left bundle branch block and left ventricular noncompaction carries uninvestigated gene mutations HCN4(G811E), SCN5A(L1988R), DMD(S2384Y), and EMD(R203H). Here, we explored the possible pathogenicity of HCN4(G811E), which results in a G811E substitution in hyperpolarization-activated cyclic nucleotide-gated channel 4, the main subunit of the cardiac pacemaker channel. Voltage-clamp measurements in a heterologous expression system of HEK293T cells showed that HCN4(G811E) slightly reduced whole-cell HCN4 channel conductance, whereas it did not affect the gating kinetics, unitary conductance, or cAMP-dependent modulation of voltage-dependence. Immunocytochemistry and immunoblot analysis showed that the G811E mutation did not impair the membrane trafficking of the channel subunit in the heterologous expression system. These findings indicate that HCN4(G811E) may not be a monogenic factor to cause the cardiac disorders.

Negative effect of aging on psychosocial functioning of adults with congenital heart disease.

BACKGROUND: Improvements in life expectancy among adults with congenital heart disease (ACHD) provide them with unique challenges throughout their lives and age-related psychosocial tasks in this group might differ from those of healthy counterparts. This study aimed to clarify age-related differences in psychosocial functioning in ACHD patients and determine the factors influencing anxiety and depression. METHODS AND RESULTS: A total of 133 ACHD patients (aged 20-46) and 117 reference participants (aged 20-43) were divided in 2 age groups (20 s and 30 s/40 s) and completed the Hospital Anxiety and Depression Scale, Independent-Consciousness Scale, and Problem-Solving Inventory. Only ACHD patients completed an illness perception inventory. ACHD patients over 30 showed a significantly greater percentage of probable anxiety cases than those in their 20 s and the reference group. Moreover, ACHD patients over 30 who had lower dependence on parents and friends, registered higher independence and problem-solving ability than those in their 20 s, whereas this element did not vary with age in the reference participants. Furthermore, ACHD patients may develop an increasingly negative perception of their illness as they age. The factors influencing anxiety and depression in patients were aging, independence, problem-solving ability, and NYHA functional class. CONCLUSIONS: Although healthy people are psychosocially stable after their 20 s, ACHD patients experience major differences and face unique challenges even after entering adulthood.

Predictive factors of negative outcome in initial atropine therapy for infantile hypertrophic pyloric stenosis.

BACKGROUND: The predictive factors of negative outcome in initial i.v. atropine (IA) therapy of infantile hypertrophic pyloric stenosis (IHPS) are unknown. Conservative therapy for IHPS is useful for infants because it does not have the risk of surgical and anesthetic stress, but some cases of atropine therapy result in failure. This study clarified the predictive markers of negative outcome in initial atropine therapy for IHPS. METHODS: Seventy-six patients with IHPS admitted from 1998 to 2011 were included in this study. The predictive risk factors of negative outcome in initial atropine therapy for IHPS were evaluated. RESULTS: Thirty-one patients initially underwent non-operative therapy for IHPS during the study period. Of the 31 patients, 18 (58%) ceased projectile vomiting (PV) with IA and subsequent oral atropine. Univariate analysis showed that lack of bodyweight gain before treatment, elevated urine potassium at admission, and PV occurring ≥5 times (PV ≥5) in total for 3 days from IA initiation were predictive risk factors for negative outcome in IHPS. Multivariate analysis identified only PV ≥5 in total for 3 days after IA initiation as independently associated with failure of atropine for IHPS. CONCLUSIONS: PV ≥5 in total for 3 days after IA initiation is a potential indicator of negative outcome of IA in IHPS patients. The present results provide valuable information for determining whether early surgical intervention for IHPS or initial atropine therapy is the best option.

Tailor-made circulatory management based on the stress-velocity relationship in preterm infants.

Preterm infants frequently experience pulmonary hemorrhage or cerebral intraventricular hemorrhage after birth. The immature myocardium of the left ventricle faces a high afterload after the baby is separated from the placenta. However, the preterm left ventricle has limited ability to respond to such an increase in afterload. This results in depressed cardiac function and a deterioration in hemodynamics. We speculated that the perinatal deterioration in cardiac performance would be closely related to serious hemorrhages. To prove our hypothesis, we studied the interrelationship between the perinatal changes in cardiac performance and the incidences of intraventricular and pulmonary hemorrhage. We obtained the stress-velocity relationship (rate-corrected mean fiber shortening velocity and end-systolic wall stress relationship) by M-mode echocardiography and arterial blood pressure measurement. We found that the incidences of intraventricular and/or pulmonary hemorrhages were higher in infants with an excessive afterload, which resulted in a decrease in the function of the left ventricle. We suggest that careful attention to keep the afterload at an acceptable level by vasodilator therapy and sedation may reduce or prevent these serious complications. In this review, we will discuss our data along with related literature.

Comparison of the clinical presentation, treatment, and outcome of fulminant and acute myocarditis in children.

BACKGROUND: Myocarditis (MC) is an important cause of cardiac dysfunction in children. Fulminant MC is sometimes fatal, and sequelae may develop during follow-up. We conducted a nationwide survey to determine the clinico-epidemiological features of MC in Japanese children and adolescents. METHODS AND RESULTS: Survey questionnaires were mailed to 627 hospitals, which were asked if they had treated MC patients aged between 1 month and 17 years during the period from January 1997 through December 2002. Responses were collected until December 2005, and data were collected and analyzed until January 2008. A total of 169 patients were reported: 64 fulminant cases, 89 acute cases, and 8 chronic cases. Incidence was 43.5 cases/year and 0.26 cases/100,000. Pathogens were identified in 37 patients; coxsackie virus accounted for 60%. Major cardiovascular manifestations at onset were congestive heart failure, refractory arrhythmia, and syncope in 70, 37, and 17 patients, respectively. Intravenous immunoglobulin was administered to 73 patients. Mechanical support seemed to be effective and life-saving. Among the 169 patients, 123 survived. Cardiovascular sequelae were reported in 49 patients. CONCLUSIONS: The survival rate for children with fulminant MC was disappointing. Overall, two-thirds of survivors had no sequelae. Mechanical support may reduce the mortality and the risk of clinical worsening.

A case of cor triatriatum with an abnormal P wave: the pacemaker action from the specialized tissue in the abnormal septum.

A boy presented with an abnormal P wave shown on an electrocardiogram (ECG) checkup at school. An echocardiogram and contrast-enhanced computed tomography (CT) showed cor triatriatum with a slit-like opening between the accessory chamber and the left atrium located along the interatrial septum. The boy underwent open heart surgery for excision of the anomalous membrane, and a postoperative ECG showed normal P waves. The excised tissue was examined immnunohistopathologically using antihyperpolarization-activated cyclic nucleotide-gated potassium channel 4 (HCN4) antibody and other staining. The authors confirmed the existence of cells positive to HCN4, indicating that they were sinoatrial node cells or at least cells with electrical automaticity.

Increased P-selectin expression on platelets and decreased plasma thrombomodulin in Fontan patients.

BACKGROUND: Thromboembolic events account for significant morbidity and mortality after the Fontan procedure, but the underlying mechanisms remain unclear. P-selectin on platelets indicates platelet activation. Thrombomodulin (TM), a receptor for thrombin and a major anticoagulant proteoglycan on the endothelial membrane, reflects the anticoagulant activity of the endothelium. The present study investigated the hypothesis that the balance between platelet activation and endothelial biological function is impaired in Fontan patients. METHODS AND RESULTS: Platelet P-selectin as a marker of platelet activation, plasma TM levels and protein C activity, as markers of anticoagulant activity of the endothelium, and thrombin-antithrombin complex III (TAT) were examined in 43 Fontan patients. P-selectin levels on platelets (4.5 +/-1.4 vs 3.4 +/-0.4 mean fluorescence intensity, P<0.001) and TAT levels (80.2 +/-322.6 vs 1.9 +/-0.9 ng/ml, P<0.05) were significantly higher in Fontan patients than in control subjects. On the other hand, plasma TM levels (1.5 +/-0.8 vs 2.2 +/-0.3 FU/ml, P<0.01) and protein C activity (71 +/-35 vs 118 +/-25%, P<0.001) were significantly lower in Fontan patients compared with controls. These abnormalities were not seen in patients after other surgical procedures for congenital heart disease. CONCLUSIONS: Platelet activation is enhanced and endothelial function is impaired in patients after the Fontan procedure, which may partly explain the thromboembolic complications in Fontan patients.

Percutaneous transluminal coronary angioplasty for postoperative left coronary artery stenosis following surgical reconstruction of congenital atresia of the left main coronary artery.

Congenital atresia of the left main coronary ostium is a rare coronary artery anomaly. A 3-year-old boy who was asymptomatic had a heart murmur because of mitral regurgitation. He underwent reconstruction of the left main coronary artery, but stenosis occurred in the early postoperative period. Although the patient underwent repair of the coronary artery stenosis, the distal portion of the left coronary artery re-stenosed. Percutaneous transluminal coronary angioplasty for the stenosis was performed successfully and there has not been any sign of re-stenosis for 30 months to date.

Risk factors for in-hospital mortality during infective endocarditis in patients with congenital heart disease.

Despite developments in preventative and medical therapy, infective endocarditis (IE) carries a high rate of mortality. Risk factors for mortality are unknown in pediatric and adult patients with congenital heart disease (CHD). We determined the risk factors for in-hospital mortality in pediatric and adult patients with CHD. A retrospective observational cohort study was conducted from January 1997 to December 2001 in Japan. Of the 239 patients for whom complete data were available, 216 patients with CHD were identified. Outcomes were alive or deceased. The proposed modified Duke's criteria identified 137 patients, aged 1 month to 62 years with a median of 12 years, with IE. In-hospital mortality was 10%. Four risk factors were independently associated with mortality by stepwise logistic regression analysis: (1) vegetation size > or =20 mm (odds ratio 40.6, 95% confidence interval 2.42 to 681); (2) age <1 year (odds ratio 19.5, 95% confidence interval 1.74 to 219); (3) presence of heart failure (odds ratio 7.16, 95% confidence ratio 1.34 to 38.4); and (4) Staphylococcus aureus as a causative organism (odds ratio 5.68, 95% confidence interval 1.16 to 27.9). Surgical intervention emerged as a predictive factor for lower in-hospital mortality (odds ratio 0.045, 95% confidence interval 0.003 to 0.70) by stepwise logistic regression analysis. In conclusion, surgical intervention, which decreases the risk of in-hospital mortality, should always be considered.

Nationwide survey of palivizumab for respiratory syncytial virus prevention in Japanese children with congenital heart disease.

A questionnaire study was performed to determine the current status of palivizumab prophylaxis against respiratory syncytial virus infection in Japanese children with congenital heart disease <2 years of age. Palivizumab prophylaxis decreased the respiratory syncytial virus hospitalization rate by 42.8%.

Association between sporting event attendance and self-rated health: an analysis of multiyear cross-sectional national data in Japan.

BACKGROUND: This study examined the extent to which sporting event attendance is associated with self-rated health. Drawing from an economic model of health production and psychological research on the health benefits of psychosocial resources, sporting event attendance was hypothesized to have a positive relationship with self-rated health. METHODS: A two-level multilevel ordered logistic regression was used to analyze multiyear cross-sectional data collected from national surveys in Japan. RESULTS: The results demonstrate that, controlling for the effects of personal and environmental characteristics, sporting event attendance positively correlates with self-rated health over a 12-year period. Specifically, when compared to individuals who did not attend any sporting event during the past year, those who attended a sporting event were 33% more likely to indicate a higher level of self-rated health. CONCLUSIONS: These findings provide evidence for a positive association between sport spectatorship and the perception of general health and contribute to the literature examining the relationship between sport spectatorship and health outcomes.

Elevated vascular endothelial growth factor levels are associated with aortopulmonary collateral vessels in patients before and after the Fontan procedure.

BACKGROUND: Aortopulmonary collaterals (APCs) are frequently observed before and after the Fontan procedure. However, the mechanism of the development of APCs is unknown. We hypothesized that one or several antiangiogenic and/or angiogenic growth factors might play a role in the development of APCs. METHODS: Eighty-five patients were enrolled and divided into 3 groups (Fontan group: 30 patients after the Fontan procedure, cyanotic group: 29 patients with cyanotic heart disease, and control group: 26 patients with cyanotic heart disease after biventricular repair). We measured basic fibroblast growth factor, vascular endothelial growth factor (VEGF), hepatocyte growth factor, and endostatin at catheterization. Angiographic evaluation for the presence of APCs using a 4-point scale (grade 1: absent APCs, > or = grade 2: significantly present APCs) was performed, and the relation of the serum levels of these factors to the presence of APCs was assessed. RESULTS: The grade of APCs significantly increased in the Fontan group, but it decreased in the control group. The serum VEGF levels were higher in the Fontan group (280 +/- 174 pg/mL) and the cyanotic group (302 +/- 245 pg/mL) than in the control group (111 +/- 91 pg/mL) (P = .0004), and they were higher in patients with APCs (383 +/- 204 pg/mL) than in those without APCs (115 +/- 65 pg/mL) (P < .0001). There was no significant difference in the serum basic fibroblast growth factor, hepatocyte growth factor, and endostatin levels between the 3 groups. CONCLUSIONS: Aortopulmonary collaterals increase after the Fontan procedure. Serum VEGF levels are associated with the presence of APCs. Vascular endothelial growth factor may play a role in the development of APCs in patients with cyanotic heart disease and after the Fontan procedure.

Comparison of metamotivational dominance and cultural identity between Japanese National Team and Maori All Blacks rugby players.

This pilot study used a reversal theory framework to examine metamotivational dominance of rugby players on the Maori All Blacks (MABs) squad of New Zealand and the Japanese National Team (JNT). Since the two groups have different cultural team demographics, cultural identity was also examined. Twenty six players from the MABs and 31 from the JNT completed questionnaires on metamotivational dominance and cultural identity. In terms of metamotivational dominance, the findings indicated that the MABs were more playful minded and spontaneous oriented than the JNT. Regarding cultural identity, the JNT showed a greater knowledge of their own culture and higher comfort level in their cultural context, while the MABs felt more positive and willing to sustain their own culture. The motivational personality differences between the teams may reflect the style of play that is valued within each team culture that is, flair, spontaneity and high-risk play within Maori rugby, and structure, team unity and conformity within the JNT. This suggests that metamotivational dominance of teams and players is influenced by the cultural identity of both the individuals and the group, which may have a further impact on team cohesion and performance.

Developmental changes in ventricular diastolic function correlate with changes in ventricular myoarchitecture in normal mouse embryos.

Both genetic and epigenetic factors, such as abnormal hemodynamics, affect cardiac morphogenesis and the pathogenesis of congenital heart disease. Diastolic function is an important determinant of cardiac function, and tools for evaluating diastolic function in the embryo would be very valuable for assessment of cardiac performance. Using histological measurements of ventricular myoarchitecture, Doppler assessment of ventricular inflow velocities, and direct measurement of ventricular pressure, we investigated developmental changes of ventricular diastolic function in the mouse embryos from embryonic days 9.5 to 19.5. Regression analysis showed that peak velocity of A wave (an index of passive compliance) correlated with the area of trabecular myocardium in right ventricle (RV) (r2=0.92, P<0.0001) and left ventricle (LV) (r2=0.93, P<0.0001). Peak velocity of E wave (an index of active relaxation) exponentially correlated with the area of compact myocardium in RV (r2=0.98, P<0.0001) and LV (r2=0.97, P<0.0001). We used these techniques to analyze FOG-2 null embryos. FOG-2 null embryos had thin compact myocardium, higher EDP and E/A ratio, smaller -dP/dt, and diminished sucking pressure than wild-type littermates, indicating that decreased ventricular diastolic function might be the primary cause of embryonic lethality. In conclusion, during embryogenesis the development of compact myocardium tightly regulates the development of ventricular distensibility. Our study in normal mice forms the basis for future studies of embryonic cardiac function in genetically manipulated mice with abnormalities of the cardiovascular system.

Targeted disruption of hesr2 results in atrioventricular valve anomalies that lead to heart dysfunction.

Genes involved in the Notch signaling pathway have been shown to be critical regulators of cardiovascular development. In vitro studies have revealed that the Notch signaling pathway directly regulates transcription of hairy and enhancer of split-related (hesr) genes, encoding basic helix-loop-helix transcription factors. To assess the functional role of hesr genes in cardiovascular development, we generated mice with a targeted disruption of the hesr2 gene and used echocardiography to analyze heart function of the mutant mice. In the early postnatal period, a majority of hesr2 homozygous mice die as a result of congestive heart failure accompanied by pronounced heart enlargement. Transthoracic echocardiography on 5-day-old homozygous mice revealed tricuspid and mitral valve regurgitation and a dilated left ventricular chamber with markedly diminished fractional shortening of the left ventricle. The hemodynamic anomalies were accompanied by morphological changes, such as dysplastic atrioventricular (AV) valves, a perimembranous ventricular septal defect, and a secundum atrial septal defect. AV valve regurgitations attributable to dysplasia of the AV valves were most likely responsible for the heart dysfunction in hesr2 homozygous mice. These observations indicate that the Notch signaling target hesr2 plays an important role in the formation and function of the AV valves. In addition, hesr2 activity may be important for proper development of cardiomyocytes, thereby assuring normal left ventricular contractility. Because of the unique spectrum of cardiac anomalies expressed by hesr2-null mice, they represent a useful model system for elucidating the genetic basis of heart dysfunction.

Risk factors for arrhythmia and late death in patients with right ventricle to pulmonary artery conduit repair--Japanese multicenter study.

BACKGROUND: Arrhythmia and late cardiac deaths are thought to be major complications in patients after right ventricle (RV) to pulmonary artery (PA) conduit repair, although the incidence and predictors of these complications remain unknown. The aim of this study was to clarify the incidence and risk factors for arrhythmia and late deaths in patients with the RV to PA conduit repair through a Japanese multicenter study. METHODS: Three hundred fifty-one hospital survivors who underwent the RV to PA conduit repair before 1995 were studied. RESULTS: Survival rate after repair was 92% at 10 years, 88% at 20 and 25 years, respectively. Late death was observed in 30 (8.5%) including 4 patients with sudden death (SD). Higher right ventricular pressure (p = 0.02), larger cardio-thoracic ratio after repair (p = 0.02) and higher incidence of brady- or tachy-arrhythmia and SD (9/30) were associated with late death. Six (1.7%) patients developed ventricular tachycardia or ventricular fibrillation (VT/Vf). There were 22 patients who had 23 new-onset supraventricular tachy-arrhythmia (SVT). Right ventricular hypertension (p = 0.04) was associated with VT/Vf or SD. Male sex (p < 0.01), absence of previously aorto-pulmonary shunt (p < 0.05), older age at repair (p < 0.01) or longer length of follow-up (p < 0.01) were associated with SVT. CONCLUSION: Arrhythmia and late sudden death are relatively common late after the RV to PA conduit repair. Our data support recent surgical strategies of earlier primary operation and timely reoperation for progressive right ventricular outflow stenosis that may reduce the incidence of late arrhythmias and SD.

Role of TBX1 in human del22q11.2 syndrome.

BACKGROUND: Del22q11.2 syndrome is the most frequent known chromosomal microdeletion syndrome, with an incidence of 1 in 4000-5000 livebirths. It is characterised by a 3-Mb deletion on chromosome 22q11.2, cardiac abnormalities, T-cell deficits, cleft palate facial anomalies, and hypocalcaemia. At least 30 genes have been mapped to the deleted region. However, the association of these genes with the cause of this syndrome is not clearly understood. METHODS: To test for the chromosomal deletion at 22q11.2, we did fluorescence in-situ hybridisation analysis with ten probes on 22q11.2 in 235 unrelated patients with clinically diagnosed del22q11.2 syndrome. To investigate mutations in the coding sequence of TBX1, we also did genetic analysis in 13 patients from ten families who have the 22q11.2 syndrome phenotype but no detectable deletion of 22q11.2. FINDINGS: 96% (225 of 235) of patients had a defined 1.5-3-Mb deletion at 22q11.2. We identified three mutations of TBX1 in two unrelated patients without the 22q11.2 deletion-one with sporadic conotruncal anomaly face syndrome/velocardiofacial syndrome and one with sporadic DiGeorge's syndrome-and in three patients from a family with conotruncal anomaly face syndrome/velocardiofacial syndrome. We did not record these three mutations in 555 healthy controls (1110 chromosomes; p<0.0001). INTERPRETATION: Our results suggest that the TBX1 mutation is responsible for five major phenotypes in del22q11.2 syndrome. Therefore, we conclude that TBX1 is a major genetic determinant of the del22q11.2 syndrome.

Clinical correlation and prognostic predictive value of neurohumoral factors in patients late after the Fontan operation.

AIMS: We tested the hypothesis that neurohumoral activation could correlate with exercise tolerance and have a prognostic value in patients late after Fontan operation. METHODS AND RESULTS: We studied 50 consecutive patients after the Fontan operation and 10 age-matched normal controls. We measured brain and atrial natriuretic peptides, norepinephrine (NE), plasma rennin activity, aldosterone, angiotensin II, and endothelin and investigated the relationship of neurohumoral factors with exercise tolerance and central hemodynamics. We also evaluated the prognostic predictive value of these factors. All factors were significantly higher in the patients than in controls, but no factor correlated with peak oxygen consumption (peak VO2). There were significant correlations of atrial natriuretic peptide with cardiac index, NE with left ventricular ejection fraction (LVEF), and pulmonary arterial wedge pressure. After 4 years' follow-up, univariate Cox proportional hazards analysis showed that peak VO2 and LVEF could significantly predict the long-term event-free ratio. In multivariate analysis, LVEF and NE have a significant predictive value. In Kaplan-Meier event-free curves, NE combined with peak VO2 showed a significant predictive value. CONCLUSIONS: Activated neurohumoral factors are not determinants of exercise tolerance in patients late after the Fontan operation. The plasma level of NE combined with peak VO2 has a prognostic predictive value in these patients.

Left ventricular diastolic dysfunction in Ebstein's anomaly.

This study was performed to evaluate left ventricular (LV) diastolic function in patients with Ebstein's anomaly using Doppler echocardiography. We found that LV abnormal relaxation in this anomaly cannot be explained by right ventricular volume overload alone. Furthermore, LV diastolic dysfunction persists even after intracardiac repair.