A novel autosomal dominant condition consisting of congenital heart defects and low atrial rhythm maps to chromosome 9q

Congenital heart defects (CHDs) occur mostly sporadic, but familial CHD cases have been reported. Mutations in several genes, including NKX2.5, GATA4 and NOTCH1, were identified in families and patients with CHD, but the mechanisms underlying CHD are largely unknown. We performed genome-wide linkage analysis in a large four-generation family with autosomal dominant CHD (including atrial septal defect type I and II, tetralogy of Fallot and persistent left superior vena cava) and low atrial rhythm, a unique phenotype that has not been described before. We obtained phenotypic information including electrocardiography, echocardiography and DNA of 23 family members. Genome-wide linkage analysis on 12 affected, 5 unaffected individuals and 1 obligate carrier demonstrated significant linkage only to chromosome 9q21-33 with a multipoint maximum LOD score of 4.1 at marker D9S1690, between markers D9S167 and D9S1682. This 48-cM critical interval corresponds to 39 Mb and contains 402 genes. Sequence analysis of nine candidate genes in this region (INVS, TMOD1, TGFBR1, KLF4, IPPK, BARX1, PTCH1, MEGF9 and S1PR3) revealed no mutations, nor were genomic imbalances detected using array comparative genomic hybridization. In conclusion, we describe a large family with CHD and low atrial rhythm with a significant LOD score to chromosome 9q. The phenotype is representative of a mild form of left atrial isomerism or a developmental defect of the sinus node and surrounding tissue. Because the mechanisms underlying CHD are largely unknown, this study represents an important step towards the discovery of genes implied in cardiogenesis.

Turning 18 with congenital heart disease: prediction of infective endocarditis based on a large population

AIMS

The risk of infective endocarditis (IE) in adults with congenital heart disease is known to be increased, yet empirical risk estimates are lacking. We sought to predict the occurrence of IE in patients with congenital heart disease at the transition from childhood into adulthood.

METHODS AND RESULTS

We identified patients from the CONCOR national registry for adults with congenital heart disease. Potential predictors included patient characteristics, and complications and interventions in childhood. The outcome measure was the occurrence of IE up to the age of 40 and 60. A prediction model was derived using the Cox proportional hazards model and bootstrapping techniques. The model was transformed into a clinically applicable risk score. Of 10 210 patients, 233 (2.3%) developed adult-onset IE during 220 688 patient-years. Predictors of IE were gender, main congenital heart defect, multiple heart defects, and three types of complications in childhood. Up to the age of 40, patients with a low predicted risk (<3%) had an observed incidence of less than 1%; those with a high predicted risk (≥3%) had an observed incidence of 6%. The model also yielded accurate predictions up to the age of 60.

CONCLUSION

Among young adult patients with congenital heart disease, the use of six simple clinical parameters can accurately predict patients at relatively low or high risk of IE. After confirmation in other cohorts, application of the prediction model may lead to individually tailored medical surveillance and educational counselling, thus averting IE or enabling timely detection in adult patients with congenital heart disease.

Mutations in the sarcomere gene MYH7 in Ebstein anomaly

BACKGROUND

Ebstein anomaly is a rare congenital heart malformation characterized by adherence of the septal and posterior leaflets of the tricuspid valve to the underlying myocardium. An association between Ebstein anomaly with left ventricular noncompaction (LVNC) and mutations in MYH7 encoding β-myosin heavy chain has been shown; in this report, we have screened for MYH7 mutations in a cohort of probands with Ebstein anomaly in a large population-based study.

METHODS AND RESULTS

Mutational analysis in a cohort of 141 unrelated probands with Ebstein anomaly was performed by next-generation sequencing and direct DNA sequencing of MYH7. Heterozygous mutations were identified in 8 of 141 samples (6%). Seven distinct mutations were found; 5 were novel and 2 were known to cause hypertrophic cardiomyopathy. All mutations except for 1 3-bp deletion were missense mutations; 1 was a de novo change. Mutation-positive probands and family members showed various congenital heart malformations as well as LVNC. Among 8 mutation-positive probands, 6 had LVNC, whereas among 133 mutation-negative probands, none had LVNC. The frequency of MYH7 mutations was significantly different between probands with and without LVNC accompanying Ebstein anomaly (P<0.0001). LVNC segregated with the MYH7 mutation in the pedigrees of 3 of the probands, 1 of which also included another individual with Ebstein anomaly.

CONCLUSIONS

Ebstein anomaly is a congenital heart malformation that is associated with mutations in MYH7. MYH7 mutations are predominantly found in Ebstein anomaly associated with LVNC and may warrant genetic testing and family evaluation in this subset of patients.

The changing epidemiology of congenital heart disease

Congenital heart disease is the most common congenital disorder in newborns. Advances in cardiovascular medicine and surgery have enabled most patients to reach adulthood. Unfortunately, prolonged survival has been achieved at a cost, as many patients suffer late complications, of which heart failure and arrhythmias are the most prominent. Accordingly, these patients need frequent follow-up by physicians with specific knowledge in the field of congenital heart disease. However, planning of care for this population is difficult, because the number of patients currently living with congenital heart disease is difficult to measure. Birth prevalence estimates vary widely according to different studies, and survival rates have not been well recorded. Consequently, the prevalence of congenital heart disease is unclear, with estimates exceeding the number of patients currently seen in cardiology clinics. New developments continue to influence the size of the population of patients with congenital heart disease. Prenatal screening has led to increased rates of termination of pregnancy. Improved management of complications has changed the time and mode of death caused by congenital heart disease. Several genetic and environmental factors have been shown to be involved in the etiology of congenital heart disease, although this knowledge has not yet led to the implementation of preventative measures. In this Review, we give an overview of the etiology, birth prevalence, current prevalence, mortality, and complications of congenital heart disease.

Rationale and design of a trial on the effect of angiotensin II receptor blockers on the function of the systemic right ventricle

BACKGROUND

Angiotensin II receptor blockers have been proven to be beneficial in left ventricular failure. In patients with a morphologic right ventricle supporting the systemic circulation, its efficacy has not yet been established.

METHODS

We designed a multicenter, prospective, randomized, double-blind, placebo-controlled trial studying the effect of valsartan in patients with a systemic right ventricle due to a congenitally or surgically corrected transposition of the great arteries. The primary end point is the change in right ventricular ejection fraction as measured by cardiovascular magnetic resonance or multidetector row cardiac computed tomography in case of pacemaker patients.

CONCLUSION

This large prospective, double-blind, randomized, placebo-controlled trial will establish the role of angiotensin II receptor blockers (valsartan) in the treatment of patients with a systemic right ventricle.

Sexuality in adult patients with congenital heart disease and their partners

Data on relational and sexuality issues in adult patients with congenital heart disease (CHD) are scarce. The present study aimed to evaluate relational and sexual behaviors, satisfaction, and functioning in a representative sample of patients with CHD and their partners. In addition, we aimed to evaluate the relation between sexuality parameters and quality of life. Relational and sexuality issues were assessed using a sexuality questionnaire in 133 patients (52% men, 37 ± 13 years old) with CHD (43 with coarctation of the aorta, 42 with transposition of great arteries, 36 with Marfan syndrome, and 12 with Eisenmenger syndrome), and 74 partners. Quality of life was assessed using the Dutch translation of the Medical Outcomes Study Short Form 36-Item Health Survey. Data were compared to an age- and gender-matched control group (n = 3,642). Seventy-one percent of patients with CHD were involved in a relationship, which was significantly less compared to controls (79%, p < 0.05). Nonetheless, patients perceived their relationship as more satisfactory compared to controls (p < 0.05). Overall, sexual satisfaction was equal in patients compared to controls, although they perceived lower body esteem (p < 0.001), decreased sexual esteem (p < 0.05), and more distress during sex (p < 0.001). Patients reported no more erectile and lubrication problems compared to partners and to controls. We found significant associations between most relational and sexual parameters and quality of life. In conclusion, many aspects of sexuality are affected in adult patients with CHD, whereas their partners remain relatively unaffected. Moreover, sexuality is an important aspect of quality of life in these patients. We advise physicians to be receptive to discuss sexuality issues and provide patients with adequate therapy.

Aortic aneurysm formation following coarctation repair by Dacron patch aortoplasty

We describe the finding of an aortic aneurysm in an asymptomatic 43-year-old male, who was managed by Dacron patch aortoplasty for native coarctation of the aorta 25 years before. The role of magnetic resonance angiography as standard imaging technique in lifelong postoperative surveillance is discussed subsequently. (Neth Heart J 2010;18:376-7.).

22q11.2 Deletion Syndrome is under-recognised in adult patients with tetralogy of Fallot and pulmonary atresia

BACKGROUND

Three quarters of patients with 22q11.2 Deletion Syndrome (22q11.2DS) have congenital heart disease (CHD), typically conotruncal heart defects. Although it is currently common practice to test all children with typical CHD for 22q11.2DS, many adult patients have not been tested in the past and therefore 22q11.2DS might be under-recognised in adults.

OBJECTIVES

To determine the prevalence of 22q11.2DS in adults with tetralogy of Fallot (TOF) and pulmonary atresia (PA)/ventricular septal defect (VSD) and to assess the level of recognition of the syndrome in adult patients.

METHODS

Patients were identified from CONCOR, a nationwide registry for adult patients with CHD. Inclusion criteria were diagnosis of TOF or PA/VSD and the availability of DNA. Patients with syndromes other than 22q11.2DS were excluded. Multiplex ligation-dependent probe amplification was used to detect 22q11.2 microdeletions.

RESULTS

479 patients with TOF and 79 patients with PA/VSD (56% male, median age 34.7 years) were included and analysed. Twenty patients were already known to have 22q11.2DS. A 22q11.2 microdeletion was detected in a further 24 patients. Thirty-one patients with TOF (6.5%) had 22q11.2DS, whereas 13 patients with PA/VSD had 22q11.2DS (16.5%). Of all 22q11.2 microdeletions, 54% (24/44) were unknown before this study.

CONCLUSION

This study shows that although the prevalence of 22q11.2DS in adults with TOF and PA/VSD is substantial, it is unrecognised in more than half of patients. As the syndrome has important clinical and reproductive implications, a diagnostic test should be considered in all adult patients with TOF and PA/VSD.

Pregnancy outcome in women with repaired versus unrepaired isolated ventricular septal defect

OBJECTIVE

To compare the risks of pregnancy complications in women with repaired and unrepaired isolated ventricular septal defect (VSD).

DESIGN

A retrospective multicentre study.

SETTING

Tertiary centres in the Netherlands and Belgium.

METHODS

Women were identified using two congenital heart disease registries. Eighty-eight women were identified who had experienced 202 pregnancies, including 46 miscarriages and nine terminations of pregnancy. Information on each completed pregnancy (n = 147; unrepaired VSD, n = 104; repaired VSD, n = 43) was obtained using medical records and telephone interviews. Data from the Generation R database (prospective cohort study; n = 9667) were used to determine the background risk (controls). Odds ratios and 95% CI were estimated using general estimation equation analysis adjusted for multiple pregnancies per woman, maternal age and parity status.

MAIN OUTCOME MEASURES

Adjusted odds ratios (AORs) for developing pregnancy complications in relation to corrective status.

RESULTS

Pregnancies in women with an unrepaired VSD were associated with a higher risk of pre-eclampsia (AOR 4.59, 95% CI 2.01-10.5, P < 0.001) compared with controls. No differences were observed when comparing women with repaired VSD and controls. Pregnancies in women with repaired VSD were associated with a higher risk of premature labour (AOR 4.02, 95% CI 1.12-14.4, P = 0.03) and small-for-gestational-age (SGA) births (AOR 4.09, 95% CI 1.27-13.2, P = 0.02) compared with women with unrepaired VSD.

CONCLUSIONS

Women with unrepaired VSD are at increased risk of pre-eclampsia, which suggests that it is not a benign condition. In addition, women with repaired VSD are at increased risk of premature labour and SGA births compared with women with unrepaired VSD.

Losartan therapy in adults with Marfan syndrome: study protocol of the multi-center randomized controlled COMPARE trial

BACKGROUND

Marfan syndrome (MFS) is one of the most common systemic disorders of connective tissue with the incidence of approximately 2-3 per 10 000 individuals. Aortic disease, leading to progressive aneurysmal dilatation and dissection is the main cause of morbidity and mortality of Marfan patients. Current treatment (e.g. beta blockers and elective surgery) does postpone but cannot prevent aortic complications in these patients. Recent studies have found transforming growth factor beta (TGF beta) to be involved in the aortic aneurysm formation. Losartan, an angiotensin II type 1 receptor blocker inhibits TGFbeta in a mouse model of Marfan syndrome leading to inhibition of aortic growth. The main objective of this trial is to assess whether losartan treatment leads to a clinically relevant decrease of aortic dilatation in adult patients with Marfan syndrome.

METHODS/DESIGN

COMPARE study (COzaar in Marfan Patients Reduces aortic Enlargement) is an open-label, randomized, controlled trial with blinded end-points. Treatment with losartan will be compared with no additional treatment after 3 years of follow-up. We will enroll 330 patients with MFS who will be randomly assigned to receive losartan or not. Patients taking beta-blockers will continue taking their standard treatment. The primary end-point is the largest change in aortic diameter at any aortic level measured by means of MRI. Secondary end-points are change in mortality, incidence of dissection, elective aortic surgery, aortic volume, aortic stiffness and ventricular function. We will also investigate gene and protein expression change in the skin under losartan therapy and create prediction models for losartan-treatment response and aortic dilatation.

DISCUSSION

The COMPARE study will provide important evidence of effects of losartan treatment in adult Marfan patient population. We expect losartan to significantly reduce the occurrence and progression of aortic dilatation. This trial investigates a wide spectrum of clinical, genetic and biochemical effects of losartan aiming to provide further insight in the pathogenesis and treatment of Marfan syndrome.

TRIAL REGISTRATION

Netherlands Trial Register NTR1423.

Intra-observer and interobserver variability of biventricular function, volumes and mass in patients with congenital heart disease measured by CMR imaging

Cardiovascular magnetic resonance (CMR) imaging provides highly accurate measurements of biventricular volumes and mass and is frequently used in the follow-up of patients with acquired and congenital heart disease (CHD). Data on reproducibility are limited in patients with CHD, while measurements should be reproducible, since CMR imaging has a main contribution to decision making and timing of (re)interventions. The aim of this study was to assess intra-observer and interobserver variability of biventricular function, volumes and mass in a heterogeneous group of patients with CHD using CMR imaging. Thirty-five patients with CHD (7-62 years) were included in this study. A short axis set was acquired using a steady-state free precession pulse sequence. Intra-observer and interobserver variability was assessed for left ventricular (LV) and right ventricular (RV) volumes, function and mass by calculating the coefficient of variability. Intra-observer variability was between 2.9 and 6.8% and interobserver variability was between 3.9 and 10.2%. Overall, variations were smallest for biventricular end-diastolic volume and highest for biventricular end-systolic volume. Intra-observer and interobserver variability of biventricular parameters assessed by CMR imaging is good for a heterogeneous group of patients with CHD. CMR imaging is an accurate and reproducible method and should allow adequate assessment of changes in ventricular size and global ventricular function.

Prevalence of congenital heart defects in neuroblastoma patients: a cohort study and systematic review of literature

Data on the prevalence of congenital heart defects (CHD) in neuroblastoma patients are inconsistent. If CHD are more common in neuroblastoma patients than in the general population, cardiac screening might be warranted. In this study we used echocardiography to determine the prevalence of CHD in a single centre cohort of surviving neuroblastoma patients. In addition, we performed a systematic review of the literature. Echocardiography was performed in 119 of 133 patients (89.5%). Only two patients (1.7%) had CHD. The prevalence of CHD was not significantly different from a previously published control group of 192 leukaemia patients examined by echocardiography (P = 0.49). Literature search revealed 17 studies, showing prevalence rates of CHD in neuroblastoma patients ranging from 0 to 20%. Prevalence was less than 3.6% in the majority of studies. Most studies lacked information on validity. We conclude that current evidence does not support standard cardiac screening in all patients with neuroblastoma.

Comparison of pregnancy outcomes in women with repaired versus unrepaired atrial septal defect

OBJECTIVE

To compare the risks of complications during pregnancy in women with repaired and unrepaired atrial septal defects (ASDs) without associated complex cardiac lesions.

DESIGN

A retrospective multicentre study.

SETTING

Tertiary centres in the Netherlands and Belgium.

POPULATION

Women with ASD without associated complex cardiac lesions.

METHODS

Women were identified using two congenital heart disease registries. One hundred women were identified who had 243 pregnancies, including 49 miscarriages and six terminations of pregnancy. Detailed information on each completed pregnancy (n = 188; unrepaired ASD, n = 133; repaired ASD, n = 55) was obtained using medical records and telephone interviews. In addition, data from the Generation R database (a prospective cohort study; n = 9667) were used to determine the background risk (control group).

MAIN OUTCOME MEASURES

Adjusted odds ratios (AORs) for cardiac, obstetric and neonatal events controlled for multiple pregnancies per woman using general estimating equation analysis.

RESULTS

Women with an unrepaired ASD had a higher risk of neonatal events (AOR = 2.99, 95% confidence interval [CI] 1.14-7.89, P = 0.027) than women with a repaired ASD. The risk of cardiac and obstetric complications was comparable between women with unrepaired and repaired ASDs. Compared with the general population, women with an unrepaired ASD had higher risks of pre-eclampsia (AOR = 3.54, 95% CI 1.26-9.98, P = 0.017), small-for-gestational-age births (AOR = 1.95, 95% CI 1.15-3.30, P = 0.013) and fetal mortality (AOR = 5.55, 95% CI 1.77-17.4, P = 0.003). By contrast, no differences were observed when comparing women with a repaired ASD versus controls.

CONCLUSIONS

Women with an unrepaired ASD are at increased risk of neonatal events in comparison with women with a repaired ASD. Compared with the general population, women with an unrepaired ASD are at increased risk of pre-eclampsia, small-for-gestational-age births and fetal mortality.

An Unusual Cause of Hypertension in Pregnancy

Aortic coarctation is an unusual cause of hypertension in pregnancy. We report the case of a 34-year-old woman with severe hypertension after surgical repair of aortic coarctation in childhood. An MRI showed a residual stenosis of the aortic arch and a small aneurysm. Pregnant postcoarctectomy patients are at an increased risk for developing hypertension during pregnancy due to residual aortic gradients and abnormal vascular reactivity of the precoarctation vessels. Women after repair of aortic coarctation should be closely monitored for blood pressure during pregnancy.

Down syndrome: a cardiovascular perspective

This review focuses on the heart and vascular system in patients with Down syndrome. A clear knowledge on the wide spectrum of various abnormalities associated with this syndrome is essential for skillful management of cardiac problems in patients with Down syndrome. Epidemiology of congenital heart defects, cardiovascular aspects and thyroid-related cardiac impairment in patients with Down syndrome will be discussed.

Down syndrome: a cardiovascular perspective

This review focuses on the heart and vascular system in patients with Down syndrome. A clear knowledge on the wide spectrum of various abnormalities associated with this syndrome is essential for skillful management of cardiac problems in patients with Down syndrome. Epidemiology of congenital heart defects, cardiovascular aspects and thyroid-related cardiac impairment in patients with Down syndrome will be discussed.

Tricuspid valve surgery in adults with a dysfunctional systemic right ventricle: repair or replace?

BACKGROUND

In patients with a right ventricle (RV) in the systemic position, tricuspid valve surgery for regurgitation beyond adolescence is a subject of debate. The aim of the present study was to evaluate the complications, survival, and benefit of tricuspid surgery in adult patients with an atrium-level correction for transposition of the great arteries or congenitally corrected transposition of the great arteries.

METHODS AND RESULTS

All adult patients (n=16; 7 men, 9 women; age 35+/-11 years) who underwent tricuspid valvuloplasty (n=8) or replacement (n=8) in the period 1999 to 2008 were included. Complications and survival were analyzed, and postoperative changes in RV function and functional class were evaluated. Tricuspid regurgitation was graded 1 to 4 according to its severity, RV dysfunction was graded as 1 to 4 (1=no dysfunction to 4=severe dysfunction), and functional status was determined according to New York Heart Association class. Although complications occurred in 11 patients, all could be managed adequately. Three patients died 109, 180, and 659 days after surgery, respectively, the first patient after tricuspid valve replacement and the latter 2 after tricuspid valvuloplasty. Overall, tricuspid valve function improved (from grade 3.1+/-0.8 to 0.9+/-1.0; P=0.001) and functional class improved (from 2.7+/-0.6 to 2.1+/-0.8; P=0.007), whereas RV function remained unchanged. After tricuspid valvuloplasty, however, recurrent moderate tricuspid valve regurgitation was observed frequently (n=3; 37%).

CONCLUSIONS

Mortality is rather low after tricuspid surgery in adult patients with mild to moderate RV dysfunction. In general, tricuspid valve function and functional class improve significantly after surgery, and systemic RV function is preserved. Tricuspid valvuloplasty, however, is associated with a high rate of recurrence of regurgitation.

Mechanisms for cardiac output augmentation in patients with a systemic right ventricle

BACKGROUND

Conflicting data have been published on the differences in cardiac response to exercise between patients with an atrially switched transposition of the great arteries (TGA), and patients with a congenitally corrected TGA (ccTGA). The purpose of our study was to evaluate the differences in cardiac response to exercise in these 2 patient groups with a systemic right ventricle (RV).

METHODS

Thirty four patients (62% male; mean 35, range 21-69 years) with a systemic RV (20 with an atrially switched TGA and 14 with a ccTGA) were included. Exercise tests with Portapres measurements were performed to assess maximal exercise capacity (V'O(2peak)), cardiac index, stroke volume index, and heart rate augmentation. Cardiac function was assessed by Cardiovascular Magnetic Resonance or Computed Tomography, and serum NT-proBNP levels.

RESULTS

We found that both groups were able to significantly augment cardiac index during exercise. Cardiac index augmentation during exercise was positively related to V'O(2peak) (r=0.37, p<0.05), and independent of resting cardiac function. Although the increase in cardiac index during exercise was similar in both patients with TGA and with ccTGA, mechanisms to achieve this increase differed between groups. ccTGA patients increased both stroke volume and heart rate during exercise. Atrially switched TGA patients augmented heart rate during exercise, but failed to increase stroke volume.

CONCLUSION

Mechanisms to achieve cardiac output augmentation differ between ccTGA patients and TGA patients. We suggest that therapeutic approaches should be tailored to the specific patient group to avoid counterproductive effects.

Recurrence of cerebrovascular events in young adults with a secundum atrial septal defect

BACKGROUND

The recurrence rate for cerebrovascular ischemic events in patients after a first TIA or CVA with an atrial septal defect type 2 (ASD2) remains unknown. At present, there are no guidelines with respect to appropriate treatment. The aim of this study was to determine incidence rates of recurrent cerebrovascular events in patients with ASD2.

METHODS

A multicenter, retrospective study was performed at selected centres in The Netherlands, United Kingdom and United States. All patients with ASD2 and a prior cerebrovascular event were identified from available databases. Clinical data were retrieved from medical files, electronic databases and radiographic charts.

RESULTS

Fifty-six adult patients born between 1950 and 1990 (median age at first cerebrovascular event 37.5, range 15-53 years) were recruited. Recurrent events (9 TIA, 2 CVA) were recorded in 11 patients (19.6%) during a median follow-up time of 5.3 years (range 0.2-28.9). Non-closure of the defect was the only significant predictor of a recurrent event (p=0.01).

CONCLUSION

Patients with an ASD2 and a history of a cerebrovascular ischemic event have a substantial risk for recurrent events. Closure of the ASD2 seems to substantially decrease the risk of recurrence. However, prospective randomized trials are needed to confirm our findings.

False heart rate feedback and the perception of heart symptoms in patients with congenital heart disease and anxiety

Background

Little is known about the mechanisms explaining an increased perception of heart symptoms in congenital heart disease (ConHD). In the present study, it was suggested that a combination of high trait anxiety and disease history increases the perception of heart symptoms.

Purpose

It was tested whether false heart cues will result in an increased perception of heart symptoms in patients with ConHD and anxiety.

Method

Thirty-six patients with ConHD and 44 healthy controls performed two exercise tasks. During one of the exercise tasks, participants were exposed to a false heart cue consisting of false heart rate feedback (regular or irregular). Perceived heart symptoms were assessed and heart rate, arterial partial pressure of CO₂, and respirator rate were monitored continuously.

Results

In line with the predictions, false heart rate feedback resulted in an increased perception of heart symptoms in high trait anxious patients with ConHD that could not be explained by acute heart dysfunction. However, unexpectedly, this effect was not observed immediately after the false heart rate feedback task but after a second exercise task without false feedback.

Conclusion

The results suggest that not the sole presence of ConHD but ConHD in combination with high trait anxiety results in a vulnerability to overperceive heart symptoms.