Rare and private variations in neural crest, apoptosis and sarcomere genes define the polygenic background of isolated Tetralogy of Fallot.

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease. Its genetic basis is demonstrated by an increased recurrence risk in siblings and familial cases. However, the majority of TOF are sporadic, isolated cases of undefined origin and it had been postulated that rare and private autosomal variations in concert define its genetic basis. To elucidate this hypothesis, we performed a multilevel study using targeted re-sequencing and whole-transcriptome profiling. We developed a novel concept based on a gene's mutation frequency to unravel the polygenic origin of TOF. We show that isolated TOF is caused by a combination of deleterious private and rare mutations in genes essential for apoptosis and cell growth, the assembly of the sarcomere as well as for the neural crest and secondary heart field, the cellular basis of the right ventricle and its outflow tract. Affected genes coincide in an interaction network with significant disturbances in expression shared by cases with a mutually affected TOF gene. The majority of genes show continuous expression during adulthood, which opens a new route to understand the diversity in the long-term clinical outcome of TOF cases. Our findings demonstrate that TOF has a polygenic origin and that understanding the genetic basis can lead to novel diagnostic and therapeutic routes. Moreover, the novel concept of the gene mutation frequency is a versatile measure and can be applied to other open genetic disorders.

Cardiac outcomes in adults with supravalvar aortic stenosis.

AIMS: Supravalvar aortic stenosis is a rare form of left ventricular outflow tract obstruction that is often progressive in childhood. Little data are available on outcomes in the adult population. Our aim was to define cardiac outcomes in adults with supravalvar aortic stenosis. METHODS AND RESULTS: This is a multicentre retrospective study of cardiac outcomes in adults (≥18 years) with supravalvar aortic stenosis. We examined: (i) adverse cardiac events (cardiovascular death, myocardial infarction, stroke, heart failure, sustained arrhythmias, and infective endocarditis) and (ii) the need for cardiac surgery in adulthood. One hundred and thirteen adults (median age at first visit 19 years; 55% with Williams-Beuren syndrome; 67% with surgical repair in childhood) were identified. Adults without Williams-Beuren syndrome had more severe supravalvar aortic stenosis and more often associated left ventricular outflow tract obstructions (P < 0.001). In contrast, mitral valve regurgitation was more common in patients with Williams-Beuren syndrome. Eighty-five per cent of adults (96/113) had serial follow-up information (median follow-up 6.0 years). Of these patients, 13% (12/96) had an adverse cardiac event and 13% (12/96) had cardiac operations (7 valve repair or replacements, 4 supravalvar aortic stenosis repairs, 1 other). Cardiac surgery was more common in adults without Williams-Beuren syndrome (P = 0.007). Progression of supravalvar aortic stenosis during adulthood was rare. CONCLUSION: Adults with supravalvar aortic stenosis remain at risk for cardiac complications and reoperations, while progression of supravalvar aortic stenosis in adulthood is rare. Valve surgery is the most common indication for cardiac surgery in adulthood.

Psychosocial situation in adults with congenital heart defects today and 20 years ago: Any changes?

BACKGROUND: While diagnosis and treatment of congenital heart diseases have improved over the last two decades, data regarding the course of psychosocial parameters is missing. METHODS: In a cross-sectional study, 283 adults with congenital heart disease completed a slightly modified questionnaire that was applied in a comparable study twenty years ago. Significant differences between the two populations as well as possible predictors of psychosocial burden for the recent population were sought. RESULTS: Despite the presence of more complex heart defects in the current cohort (p < 0.001), both populations exhibited similar values in the Ability Index. Furthermore, the current cohort reported significantly improved outcomes regarding school performance, employment, and sports. Regarding psychosocial functioning, the current cohort showed better outcomes in the domains of sadness (p < 0.01), independence (p < 0.01), understanding (p < 0.001), and acceptance (p < 0.01) of heart disease. Predictors for a worse psychosocial situation in a multiple regression analysis were anxiety, lack of curiosity, and age over 33. In the current study women, as opposed to men, reported significantly more dissatisfaction with too little information provided about their illness (p < 0.05), higher anxiety levels (p < 0.01), and heightened illness-connected burden (p < 0.05). However, women showed higher levels of independence (p < 0.01) and lower alcohol consumption (p < 0.001). CONCLUSION: The psychosocial situation of adults with congenital heart disease has improved over the span of 20 years. However, particular needs and concerns should be addressed individually via doctor-patient communication. The findings here suggest that especially female patients appear to have a higher demand for counselling information, e.g. reproduction issues.

Value of Rotational Thromboelastometry and Impedance Aggregometry for Evaluating Coagulation Disorders in Patients With Cyanotic and Nongenetic Congenital Heart Disease.

Adults with cyanotic congenital heart diseases (CCHD) have a higher risk for bleeding, but also for thrombosis. Rotational thromboelastometry (RT), using tissue factor (EXTEM), a contact activator (INTEM) or cytochalasin (FIBTEM), assesses coagulation by determining the time to initiation of clotting (CT) and clot firmness (MCF) including platelet-fibrin-interaction. The aim of this study was to evaluate RT and whole blood impedance aggregometry (IA) in CCHD compared with a control group without chronic cyanosis (NCCHD). These were used to establish normal reference ranges. We prospectively included 124 patients (76 CCHD, 48 NCCHD). Mean oxygen saturation in CCHD was 81.5%, and 98% in NCCHD (p <0.001). Fifty-five CCHD and 1 NCCHD had pulmonary hypertension. Eisenmenger syndrome was present in 39 CCHD (51.3%). Hemoglobin, hematocrit, and reticulocyte levels were significantly higher in CCHD, and they also showed more thrombocytopenia. Platelet aggregation was under normal range in 89.5% of CCHD after triggering with ADP, in 85.5% after triggering with arachidonic acid (ASPI) and in 73.7% after TRAP-6. RT showed significantly longer clotting times and reduced clot firmness in both EXTEM and INTEM tests. FIBTEM-MCF was also significantly reduced. Moderate inverse correlation was found between platelet count and erythrocytes (r = -0.608, p <0.001). Significant correlations were found between platelet number and RT-parameters as well as with all IA parameters. In conclusion, according to RT and IA, CCHD present hypocoagulable disorders. No signs of hypercoagulability were found.

Non-invasive assessment of liver alterations in Senning and Mustard patients.

BACKGROUND: Adults with congenital heart disease and ventricular dysfunction are prone to liver congestion, leading to fibrosis or cirrhosis but little is known about the prevalence of liver disease in atrial switch patients. Liver impairment may develop due to increased systemic venous pressures. This prospective study aimed to assess non-invasively hepatic abnormalities in adults who underwent Senning or Mustard procedures. METHODS: Hepatic involvement was assessed non-invasively clinically by laboratory analysis, hepatic fibrotic markers, sonography, and liver stiffness measurements [transient elastography (TE) and acoustic radiation force impulse imaging (ARFI)]. RESULTS: Overall, 24 adults who had undergone atrial switch operation (13 Senning, 11 Mustard; four female; median age 27.8 years; range 24-45 years) were enrolled. In liver stiffness measurements, only three patients had values within the normal reference. All other patients showed mild, moderate or severe liver fibrosis or cirrhosis, respectively. Using imaging and laboratory analysis, 71% of the subjects had signs of liver fibrosis (46%) or cirrhosis (25%). CONCLUSIONS: Non-invasive screening for liver congestion, fibrosis or cirrhosis could be meaningful in targeted screening for hepatic impairment in patients with TGA-ASO. As expert knowledge is essential, patients should be regularly controlled in highly specialised centres with cooperations between congenital cardiologists and hepatologists.

Characterization of TBX20 in human hearts and its regulation by TFAP2.

The T-box family of transcription factors has been shown to have major impact on human development and disease. In animal studies Tbx20 is essential for the development of the atrioventricular channel, the outflow tract and valves, suggesting its potential causative role for the development of Tetralogy of Fallot (TOF) in humans. In the presented study, we analyzed TBX20 in cardiac biopsies derived from patients with TOF, ventricular septal defects (VSDs) and normal hearts. Mutation analysis did not reveal any disease causing sequence variation, however, TBX20 is significantly upregulated in tissue samples of patients with TOF, but not VSD. In depth analysis of TBX20 transcripts lead to the identification of two new exons 3' to the known TBX20 message resembling the mouse variant Tbx20a, as well as an extended 5'UTR. Functional analysis of the human TBX20 promoter revealed a 100 bp region that contains strong activating elements. Within this core promoter region we recognized functional binding sites for TFAP2 transcription factors and identified TFAP2 as repressors of the TBX20 gene in vitro and in vivo. Moreover, decreased TFAP2C levels in cardiac biopsies of TOF patients underline the biological significance of the pathway described. In summary, we provide first insights into the regulation of TBX20 and show its potential for human congenital heart diseases.

Non-invasive assessment of liver changes in Eisenmenger patients.

BACKGROUND: Eisenmenger syndrome as a severe form of cyanotic congenital heart disease results in a complex multisystemic disorder. Due to increased systemic venous pressure and the inability to ensure systemic perfusion and metabolic requirements, the liver may develop congestion, fibrosis or cirrhosis. This study aimed to assess hepatic abnormalities in Eisenmenger patients non-invasively. METHODS AND RESULTS: 10 adults with Eisenmenger syndrome (six female; median age 44.2years; range 23-62years) were enrolled and hepatic involvement was assessed - using clinical assessment, laboratory analysis, hepatic fibrotic markers, abdominal sonography and liver stiffness measurements (transient elastography (TE) and acoustic radiation force impulse imaging (ARFI)). Using imaging and laboratory analysis, 60% (6/10) of the Eisenmenger patients had signs of liver fibrosis (5/10) or cirrhosis (1/10). While TE, however, showed no relevant liver abnormalities in any Eisenmenger patient, ARFI detected liver fibrosis in 5/10 and cirrhosis and 1/10 patients. CONCLUSIONS: Adult Eisenmenger patients are at increased risk of hepatic impairment. Non-invasive screening could be helpful in detecting liver alterations. In our small series, however, TE could not detect fibrosis or cirrhosis in any affected patient, while ARFI was very reliable. Patients should be transferred to centres, where a multidisciplinary expert knowledge is available and a close collaboration between cardiologists and hepatologists exists.

Identification and functional analysis of CITED2 mutations in patients with congenital heart defects.

Recent reports have demonstrated that mice lacking the transcription factor Cited2 die in utero showing various cardiac malformations. We present for the first time functionally relevant mutations of CITED2 in patients with congenital heart defects (CHDs). CITED2 encodes a CREBBP/EP300 interacting transcriptional modulator of HIF1A and TFAP2. To study the potential impact of sequence variations in CITED2 for CHDs in humans, we screened a cohort of 392 well-characterized patients and 192 control individuals using DHPLC, sequencing, and Amplifluor genotyping techniques. We identified 15 CITED2 nucleotide alterations. Seven of these alterations were found only in CHD patients and were not detected in controls, including three mutations leading to alterations of the amino acid sequence (p.Ser170_Gly178del, p.Gly178_Ser179ins9, and p.Ser198_Gly199del). All three of these amino acid changing mutations cluster in the serine-glycine-rich junction of the protein, to which no functionality had heretofore been assigned. Here we show that these mutations significantly reduce the capacity of CITED2 to transrepress HIF1A, and that the p.Ser170_Gly178del mutation significantly diminishes TFAP2C coactivation. This reveals a modifying role for the serine-glycine-rich region in CITED2 function. In summary, the observation of these mutations in patients with septal defects indicates that CITED2 has a causative impact in the development of CHD in humans.

Genome-wide array analysis of normal and malformed human hearts.

BACKGROUND: We present the first genome-wide cDNA array analysis of human congenitally malformed hearts and attempted to partially elucidate these complex phenotypes. Most congenital heart defects, which account for the largest number of birth defects in humans, represent complex genetic disorders. As a consequence of the malformation, abnormal hemodynamic features occur and cause an adaptation process of the heart. METHODS AND RESULTS: The statistical analysis of our data suggests distinct gene expression profiles associated with tetralogy of Fallot, ventricular septal defect, and right ventricular hypertrophy. Applying correspondence analysis, we could associate specific gene functions to specific phenotypes. Furthermore, our study design allows the suggestion that alterations associated with primary genetic abnormalities can be distinguished from those associated with the adaptive response of the heart to the malformation (right ventricular pressure overload hypertrophy). We provide evidence for the molecular transition of the hypertrophic right ventricle to normal left ventricular characteristics. Furthermore, we present data on chamber-specific gene expression. CONCLUSIONS: Our findings propose that array analysis of malformed human hearts opens a new window to understand the complex genetic network of cardiac development and adaptation. For detailed access, see the online-only Data Supplement.

d-matrix - database exploration, visualization and analysis.

BACKGROUND: Motivated by a biomedical database set up by our group, we aimed to develop a generic database front-end with embedded knowledge discovery and analysis features. A major focus was the human-oriented representation of the data and the enabling of a closed circle of data query, exploration, visualization and analysis. RESULTS: We introduce a non-task-specific database front-end with a new visualization strategy and built-in analysis features, so called d-matrix. d-matrix is web-based and compatible with a broad range of database management systems. The graphical outcome consists of boxes whose colors show the quality of the underlying information and, as the name suggests, they are arranged in matrices. The granularity of the data display allows consequent drill-down. Furthermore, d-matrix offers context-sensitive categorization, hierarchical sorting and statistical analysis. CONCLUSIONS: d-matrix enables data mining, with a high level of interactivity between humans and computer as a primary factor. We believe that the presented strategy can be very effective in general and especially useful for the integration of distinct data types such as phenotypical and molecular data.

Effect of bosentan therapy on ventricular and atrial function in adults with Eisenmenger syndrome. A prospective, multicenter study using conventional and Speckle tracking echocardiography.

BACKGROUND: The effect of bosentan on the ventricular and atrial performance in patients with Eisenmenger syndrome is unclear. In adult patients with Eisenmenger syndrome, we aimed to evaluate the midterm effect of bosentan on physical exercise, ventricular and atrial function, and pulmonary hemodynamics. METHODS: Forty adult patients before and after 24 weeks bosentan therapy underwent 6 min walk test, two-dimensional speckle tracking echocardiography, plasma NT-proBNP measurement and cardiac catheterization. RESULTS: After 24 weeks, bosentan therapy an improvement was observed regarding the 6 min walk distance from a median (quartile 1-quartile 3) of 382.5 (312-430) to 450 (390-510) m (p = 0.0001), NT-proBNP from 527.5 (201-1,691.25) to 369 (179-1,246) pg/ml (p = 0.021), right ventricular mean longitudinal systolic strain from 18 (13-22) to 19 (14.5-25) % (p = 0.004), left ventricular mean longitudinal systolic strain from 16 (12-21) to 17 (16-22) % (p = 0.001), right atrial mean peak longitudinal strain from 26 (18-34) to 28 (22-34) % (p = 0.01) and right atrial mean peak contraction strain from 11 (8-16) to 13 (11-16) % (p = 0.005). The invasively obtained Qp:Qs and Rp:Rs did not significantly change under bosentan therapy. CONCLUSIONS: In adult patients with Eisenmenger syndrome, bosentan therapy improves ventricular and atrial functions resulting in enhancement of physical exercise and reduction in the NT-proBNP level, while the pulmonary vascular resistance does not change substantially.

Treatment of pulmonary arterial hypertension (PAH): updated Recommendations of the Cologne Consensus Conference 2011.

The 2009 European Guidelines on Diagnosis and Treatment of Pulmonary Hypertension have been adopted for Germany. The guidelines contain detailed recommendations on the diagnosis of pulmonary hypertension (PH). However, the practical implementation of the European Guidelines in Germany requires the consideration of several country-specific issues and already existing novel data. This requires a detailed commentary to the guidelines, and in some aspects an update already appears necessary. In June 2010, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany. This conference aimed to solve practical and controversial issues surrounding the implementation of the European Guidelines in Germany. To this end, a number of working groups was initiated, one of which was specifically dedicated to the treatment of pulmonary arterial hypertension (PAH). This commentary describes in detail the results and recommendations of the working group on treatment of PAH which were last updated in October 2011.

The Adult Patient with Eisenmenger Syndrome: A Medical Update after Dana Point Part II: Medical Treatment - Study Results.

Eisenmenger syndrome is the most severe form of pulmonary arterial hypertension and arises on the basis of congenital heart disease with a systemic-to-pulmonary shunt. Due to the chronic slow progressive hypoxemia with central cyanosis, adult patients with the Eisenmenger syndrome suffer from a complex and multisystemic disorder including coagulation disorders (bleeding complications and paradoxical embolisms), renal dysfunction, hypertrophic osteoarthropathy, heart failure, reduced quality of life and premature death.For a long time, therapy has been limited to symptomatic options or lung or combined heart-lung transplantation. As new selective pulmonary vasodilators have become available and proven to be beneficial in various forms of pulmonary arterial hypertension, this targeted medical treatment has been expected to show promising effects with a delay of deterioration also in Eisenmenger patients. Unfortunately, data in Eisenmenger patients suffer from small patient numbers and a lack of randomized controlled studies.To optimize the quality of life and the outcome, referral of Eisenmenger patients to spezialized centers is required. In such centers, specific interdisciplinary management strategies of physicians specialized on congenital heart diseases and PAH should be warranted. This medical update emphasizes the current diagnostic and therapeutic options for Eisenmenger patients with particularly focussing on the medical treatment and corresponding study results.

The adult patient with eisenmenger syndrome: a medical update after dana point part I: epidemiology, clinical aspects and diagnostic options.

Eisenmenger syndrome is the most severe form of pulmonary arterial hypertension and arises on the basis of congenital heart disease with a systemic-to-pulmonary shunt. Due to the chronic slow progressive hypoxemia with central cyanosis, adult patients with the Eisenmenger syndrome suffer from a complex and multisystemic disorder including coagulation disorders (bleeding complications and paradoxical embolisms), renal dysfunction, hypertrophic osteoarthropathy, heart failure, reduced quality of life and premature death.For a long time, therapy has been limited to symptomatic options or lung or combined heart-lung transplantation. As new selective pulmonary vasodilators have become available and proven to be beneficial in various forms of pulmonary arterial hypertension, this targeted medical treatment has been expected to show promising effects with a delay of deterioration also in Eisenmenger patients. Unfortunately, data in Eisenmenger patients suffer from small patient numbers and a lack of randomized controlled studies.To optimize the quality of life and the outcome, referral of Eisenmenger patients to spezialized centers is required. In such centers, specific interdisciplinary management strategies of physicians specialized on congenital heart diseases and PAH should be warranted. This medical update emphasizes the current diagnostic and therapeutic options for Eisenmenger patients with particularly focussing on epidemiology, clinical aspects and specific diagnostic options.

The Adult Patient with Eisenmenger Syndrome: A Medical Update after Dana Point Part III: Specific Management and Surgical Aspects.

Eisenmenger syndrome is the most severe form of pulmonary arterial hypertension and arises on the basis of congenital heart disease with a systemic-to-pulmonary shunt. Due to the chronic slow progressive hypoxemia with central cyanosis, adult patients with the Eisenmenger syndrome suffer from a complex and multisystemic disorder including coagulation disorders (bleeding complications and paradoxical embolisms), renal dysfunction, hypertrophic osteoarthropathy, heart failure, reduced quality of life and premature death.For a long time, therapy has been limited to symptomatic options or lung or combined heart-lung transplantation. As new selective pulmonary vasodilators have become available and proven to be beneficial in various forms of pulmonary arterial hypertension, this targeted medical treatment has been expected to show promising effects with a delay of deterioration also in Eisenmenger patients. Unfortunately, data in Eisenmenger patients suffer from small patient numbers and a lack of randomized controlled studies.To optimize the quality of life and the outcome, referral of Eisenmenger patients to spezialized centers is required. In such centers, specific interdisciplinary management strategies of physicians specialized on congenital heart diseases and PAH should be warranted. This medical update emphasizes the current diagnostic and therapeutic options for Eisenmenger patients with particularly focussing on specific management and surgical aspects.

Regulation of muscle development by DPF3, a novel histone acetylation and methylation reader of the BAF chromatin remodeling complex.

Chromatin remodeling and histone modifications facilitate access of transcription factors to DNA by promoting the unwinding and destabilization of histone-DNA interactions. We present DPF3, a new epigenetic key factor for heart and muscle development characterized by a double PHD finger. DPF3 is associated with the BAF chromatin remodeling complex and binds methylated and acetylated lysine residues of histone 3 and 4. Thus, DPF3 may represent the first plant homeodomains that bind acetylated lysines, a feature previously only shown for the bromodomain. During development Dpf3 is expressed in the heart and somites of mouse, chicken, and zebrafish. Morpholino knockdown of dpf3 in zebrafish leads to incomplete cardiac looping and severely reduced ventricular contractility, with disassembled muscular fibers caused by transcriptional deregulation of structural and regulatory proteins. Promoter analysis identified Dpf3 as a novel downstream target of Mef2a. Taken together, DPF3 adds a further layer of complexity to the BAF complex by representing a tissue-specific anchor between histone acetylations as well as methylations and chromatin remodeling. Furthermore, this shows that plant homeodomain proteins play a yet unexplored role in recruiting chromatin remodeling complexes to acetylated histones.