Common Genetic Variants Contribute to Risk of Transposition of the Great Arteries.

RATIONALE: Dextro-transposition of the great arteries (D-TGA) is a severe congenital heart defect which affects approximately 1 in 4,000 live births. While there are several reports of D-TGA patients with rare variants in individual genes, the majority of D-TGA cases remain genetically elusive. Familial recurrence patterns and the observation that most cases with D-TGA are sporadic suggest a polygenic inheritance for the disorder, yet this remains unexplored. OBJECTIVE: We sought to study the role of common single nucleotide polymorphisms (SNPs) in risk for D-TGA. METHODS AND RESULTS: We conducted a genome-wide association study in an international set of 1,237 patients with D-TGA and identified a genome-wide significant susceptibility locus on chromosome 3p14.3, which was subsequently replicated in an independent case-control set (rs56219800, meta-analysis P=8.6x10-10, OR=0.69 per C allele). SNP-based heritability analysis showed that 25% of variance in susceptibility to D-TGA may be explained by common variants. A genome-wide polygenic risk score derived from the discovery set was significantly associated to D-TGA in the replication set (P=4x10-5). The genome-wide significant locus (3p14.3) co-localizes with a putative regulatory element that interacts with the promoter of WNT5A, which encodes the Wnt Family Member 5A protein known for its role in cardiac development in mice. We show that this element drives reporter gene activity in the developing heart of mice and zebrafish and is bound by the developmental transcription factor TBX20. We further demonstrate that TBX20 attenuates Wnt5a expression levels in the developing mouse heart. CONCLUSIONS: This work provides support for a polygenic architecture in D-TGA and identifies a susceptibility locus on chromosome 3p14.3 near WNT5A. Genomic and functional data support a causal role of WNT5A at the locus.

Advocacy at the Eighth World Congress of Pediatric Cardiology and Cardiac Surgery.

The Eighth World Congress of Pediatric Cardiology and Cardiac Surgery (WCPCCS) will be held in Washington DC, USA, from Saturday, 26 August, 2023 to Friday, 1 September, 2023, inclusive. The Eighth World Congress of Pediatric Cardiology and Cardiac Surgery will be the largest and most comprehensive scientific meeting dedicated to paediatric and congenital cardiac care ever held. At the time of the writing of this manuscript, The Eighth World Congress of Pediatric Cardiology and Cardiac Surgery has 5,037 registered attendees (and rising) from 117 countries, a truly diverse and international faculty of over 925 individuals from 89 countries, over 2,000 individual abstracts and poster presenters from 101 countries, and a Best Abstract Competition featuring 153 oral abstracts from 34 countries. For information about the Eighth World Congress of Pediatric Cardiology and Cardiac Surgery, please visit the following website: [www.WCPCCS2023.org]. The purpose of this manuscript is to review the activities related to global health and advocacy that will occur at the Eighth World Congress of Pediatric Cardiology and Cardiac Surgery.Acknowledging the need for urgent change, we wanted to take the opportunity to bring a common voice to the global community and issue the Washington DC WCPCCS Call to Action on Addressing the Global Burden of Pediatric and Congenital Heart Diseases. A copy of this Washington DC WCPCCS Call to Action is provided in the Appendix of this manuscript. This Washington DC WCPCCS Call to Action is an initiative aimed at increasing awareness of the global burden, promoting the development of sustainable care systems, and improving access to high quality and equitable healthcare for children with heart disease as well as adults with congenital heart disease worldwide.

Effect of Losartan on Right Ventricular Dysfunction: Results From the Double-Blind, Randomized REDEFINE Trial (Right Ventricular Dysfunction in Tetralogy of Fallot: Inhibition of the Renin-Angiotensin-Aldosterone System) in Adults With Repaired Tetralogy of Fallot.

BACKGROUND: The effect of angiotensin II receptor blockers on right ventricular (RV) function is still unknown. Angiotensin II receptor blockers are beneficial in patients with acquired left ventricular dysfunction, and recent findings have suggested a favorable effect in symptomatic patients with systemic RV dysfunction. The current study aimed to determine the effect of losartan, an angiotensin II receptor blocker, on subpulmonary RV dysfunction in adults after repaired tetralogy of Fallot. METHODS: The REDEFINE trial (Right Ventricular Dysfunction in Tetralogy of Fallot: Inhibition of the Renin-Angiotensin-Aldosterone System) is an investigator-initiated, multicenter, prospective, 1:1 randomized, double-blind, placebo-controlled study. Adults with repaired tetralogy of Fallot and RV dysfunction (RV ejection fraction [EF] <50%) but without severe valvular dysfunction were eligible. Patients were randomly assigned between losartan (150 mg daily) and placebo with target treatment duration between 18 and 24 months. The primary outcome was RV EF change, determined by cardiovascular MRI in intention-to-treat analysis. RESULTS: Of 95 included patients, 47 patients received 150 mg losartan daily (age, 38.0±12.4 years; 74% male), and 48 patients received placebo (age, 40.6±11.4 years; 63% male). Overall, RV EF did not change in patients allocated to losartan (n=42) (44.4±5.1% to 45.2±5.0%) and placebo (n=46) (43.2±6.3% to 43.6±6.9%). Losartan did not significantly improve RV EF in comparison with placebo (+0.51%; 95% confidence interval, -1.0 to +2.0; P=0.50). No significant treatment effects were found on secondary outcomes: left ventricular EF, peak aerobic exercise capacity, and N-terminal pro-brain natriuretic peptide (P>0.30 for all). In predefined subgroup analyses, losartan did not have a statistically significant impact on RV EF in subgroups with symptoms, restrictive RV, RV EF<40%, pulmonary valve replacement, or QRS fragmentation. However, in a post hoc analysis, losartan was associated with improved RV EF in a subgroup (n=30) with nonrestrictive RV and incomplete remodeling (QRS fragmentation and previous pulmonary valve replacement) (+2.7%; 95% confidence interval, +0.1 to +5.4; P=0.045). CONCLUSIONS: Losartan had no significant effect on RV dysfunction or secondary outcome parameters in repaired tetralogy of Fallot. Future larger studies may determine whether there might be a role for losartan in specific vulnerable subgroups. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02010905.

Anomalous coronary artery originating from the opposite sinus of Valsalva (ACAOS), fractional flow reserve- and intravascular ultrasound-guided management in adult patients.

OBJECTIVES: To describe the use of fractional flow reserve (FFR) and intravascular ultrasound (IVUS) in the evaluation of patients with anomalous coronary arteries originating from the opposite sinus of Valsalva (ACAOS). BACKGROUND: ACAOS of the right and left coronary are rare, but may lead to symptoms and impose a risk for sudden cardiac death, depending on several anatomical features. Assessment and risk estimation is challenging in (nonathlete) adults, especially if they present without symptoms or with atypical complaints. METHODS: The team retrospectively studied 30 consecutive patients with ACAOS with interarterial course, who received IVUS- and FFR-guided treatment at our institution between October 2010 and September 2017. RESULTS: FFR was abnormal in only seven patients. IVUS showed the typical slit-like anatomy of the orifice in 23 patients. Based on FFR and/or IVUS results, in conjunction with the clinical presentation, clinical decision was made. A decision for intervention was made if at least two out of three entities were abnormal. Intervention implied unroofing of the coronary artery (n = 10) or coronary artery bypass grafting (n = 1). In all other patients a conservative strategy was followed. No adverse events occurred in the total population after a median of 37 (0-62) months of follow-up. CONCLUSIONS: Conservative treatment may be justifiable in adult patients with ACAOS in the presence of normal FFR and nonsuspicious symptoms, despite the presence of an interarterial course and/or slitlike orifice on IVUS. We recommend the use of FFR and IVUS in the standard work-up for adult patients with ACAOS and propose the use of a flowchart to aid in decision-making.

Tricuspid flow and regurgitation in congenital heart disease and pulmonary hypertension: comparison of 4D flow cardiovascular magnetic resonance and echocardiography.

BACKGROUND: Tricuspid valve (TV) regurgitation (TR) is a common complication of pulmonary hypertension and right-sided congenital heart disease, associated with increased morbidity and mortality. Estimation of TR severity by echocardiography and conventional cardiovasvular magnetic resonance (CMR) is not well validated and has high variability. 4D velocity-encoded (4D-flow) CMR was used to measure tricuspid flow in patients with complex right ventricular (RV) geometry and varying degrees of TR. The aims of the present study were: 1) to assess accuracy of 4D-flow CMR across the TV by comparing 4D-flow CMR derived TV effective flow to 2D-flow derived effective flow across the pulmonary valve (PV); 2) to assess TV 4D-flow CMR reproducibility, and 3) to compare TR grade by 4D-flow CMR to TR grade by echocardiography. METHODS: TR was assessed by both 4D-flow CMR and echocardiography in 21 healthy subjects (41.2 ± 10.5 yrs., female 7 (33%)) and 67 RV pressure-load patients (42.7 ± 17.0 yrs., female 32 (48%)). The CMR protocol included 4D-flow CMR measurement across the TV, 2D-flow measurement across the PV and conventional planimetric measurements. TR grading on echocardiographic images was performed based on the international recommendations. Bland-Altman analysis and intra-class correlation coefficients (ICC) were used to asses correlations and agreement. RESULTS: TV effective flow measured by 4D-flow CMR showed good correlation and agreement with PV effective flow measured by 2D-flow CMR with ICC = 0.899 (p < 0.001) and mean difference of -1.79 ml [limits of agreement -20.39 to 16.81] (p = 0.084). Intra-observer agreement for effective flow (ICC = 0.981; mean difference - 1.51 ml [-12.88 to 9.86]) and regurgitant fraction (ICC = 0.910; mean difference 1.08% [-7.90; 10.06]) was good. Inter-observer agreement for effective flow (ICC = 0.935; mean difference 2.12 ml [-15.24 to 19.48]) and regurgitant fraction (ICC = 0.968; mean difference 1.10% [-7.96 to 5.76]) were comparable. In 25/65 (38.5%) TR grade differed by at least 1 grade using 4D-flow CMR compared to echocardiography. CONCLUSION: TV effective flow derived from 4D-flow CMR showed excellent correlation to PV effective flow derived from 2D-flow CMR, and was reproducible to measure TV flow and regurgitation. Twenty-five out of 65 patients (38.5%) were classified differently by at least one TR grade using 4D-flow CMR compared to echocardiography.

Left ventricular function and exercise capacity after arterial switch operation for transposition of the great arteries: a systematic review and meta-analysis.

BACKGROUND: The arterial switch operation for transposition of the great arteries was initially believed to be an anatomical correction. Recent evidence shows reduced exercise capacity and left ventricular function in varying degrees in the long term after an arterial switch operation. OBJECTIVE: To perform a meta-analysis on long-term exercise capacity and left ventricular ejection fraction after an arterial switch operation. METHODS: A literature search was performed to cover all studies on patients who had undergone a minimum of 6 years of follow-up that reported either left ventricular ejection fraction, peak oxygen uptake, peak workload, and/or peak heart rate. A meta-analysis was performed if more than three studies reported the outcome of interest. RESULTS: A total of 21 studies reported on the outcomes of interest. Oxygen uptake was consistently lower in patients who had undergone an arterial switch operation compared with healthy controls, with a pooled average peak oxygen uptake of 87.5±2.9% of predicted. The peak heart rate was also lower compared with that of controls, at 92±2% of predicted. Peak workload was significantly reduced in two studies. Pooled left ventricular ejection fraction was normal at 60.7±7.2%. CONCLUSION: Exercise capacity is reduced and left ventricular ejection fraction is preserved in the long term after an arterial switch operation for transposition of the great arteries.

Right vEntricular Dysfunction in tEtralogy of Fallot: INhibition of the rEnin-angiotensin-aldosterone system (REDEFINE) trial: Rationale and design of a randomized, double-blind, placebo-controlled clinical trial.

Renin-angiotensin-aldosterone system (RAAS) inhibition with angiotensin II receptor blockers or angiotensin-converting enzyme inhibitors is beneficial in patients with acquired left ventricular dysfunction. Adult patients with tetralogy of Fallot (TOF) with right ventricular (RV) dysfunction are at high risk for heart failure, arrhythmias, and sudden cardiac death. However, the efficacy of RAAS inhibition has not been established in these patients. METHODS: The REDEFINE is an investigator-initiated, multicenter, prospective, randomized, double-blind, placebo-controlled trial to study the effects of the angiotensin II receptor blocker losartan (target dosage of 150 mg once daily) in adult patients with TOF. Patients with RV dysfunction in the absence of severe valvular dysfunction are eligible for inclusion. The primary end point is the change in RV ejection fraction after 18 to 24 months, as measured by cardiovascular magnetic resonance imaging. In addition, laboratory measurements, echocardiography, and cardiopulmonary exercise testing are performed. CONCLUSION: The REDEFINE trial will study the effects of RAAS inhibition with losartan in TOF patients with RV dysfunction.

Regional right ventricular remodeling and function in children with idiopathic pulmonary arterial hypertension vs those with pulmonary valve stenosis: Insights into mechanics of right ventricular dysfunction.

BACKGROUND: Right ventricular (RV) pressure overload in the context of pulmonary stenosis (PS) has a much better prognosis than in the context of idiopathic pulmonary arterial hypertension (iPAH), which may be related to differences in global and regional RV remodeling and systolic function. We compared RV mechanics in children with PS to those with iPAH, aiming to identify mechanisms and markers of RV dysfunction. METHODS: Eighteen controls, 18 iPAH and 16 PS patients were retrospectively studied. Age, BSA, and sex distribution were comparable. Two-dimensional echocardiography, blood flow and tissue Doppler, and longitudinal RV deformation were analyzed. ANCOVA-including RV systolic pressure (RVSP) and length as covariates-was used to compare patient groups. RESULTS: RV systolic pressure was higher in iPAH vs PS (96.8±25.4 vs 75.4±18.9 mm Hg, P=.011). Compared to controls, PS patients showed mild dilation (P<.01) and decreased longitudinal deformation (P<.001) at the RV apex. Compared to both PS and controls, iPAH patients showed marked spherical RV dilation (P<.001), reduced global, RV free wall and septal longitudinal deformation (iPAH -22.07%±4.35% vs controls -28.18%±1.69%; -9.98%±4.30% vs -17.45%±2.52%; P<.001) and RV postsystolic shortening (P<.001). RV transverse shortening (radial performance) was increased in PS (31.75%±10.35%; P<.001) but reduced in iPAH (-1.62%±11.11% vs controls 12.00%±7.74%; P<.001). CONCLUSION: Children with iPAH demonstrate adverse global and regional RV remodeling and mechanics compared to those with PS. Mechanisms of RV systolic dysfunction in iPAH include decreased longitudinal deformation, decreased or absent transverse shortening, and postsystolic shortening. These markers may be useful to identify children at risk of RV failure.

Secundum atrial septal defect is associated with reduced survival in adult men.

AIMS: The identification of sex differences in the prognosis of adults with a secundum atrial septal defect (ASD2) could help tailor their clinical management, as it has in other cardiovascular diseases. We investigated whether disparity between the sexes exists in long-term outcome of adult ASD2 patients. METHODS AND RESULTS: Patients with ASD2 classified as the primary defect were selected from the Dutch national registry of adult congenital heart disease. Survival stratified by sex was compared with a sex-matched general population. In a total of 2207 adult patients (mean age at inclusion 44.8 years, 33.0% male), 102 deaths occurred during a cumulative follow-up of 13 584 patient-years. Median survival was 79.7 years for men and 85.6 years for women with ASD2. Compared with the age- and sex-matched general population, survival was lower for male, but equal for female patients (P = 0.015 and 0.766, respectively). Logistic regression analyses showed that men had a higher risk of conduction disturbances (OR = 1.63; 95% CI, 1.22-2.17) supraventricular dysrhythmias (OR = 1.41; 1.12-1.77), cerebrovascular thromboembolic events (OR = 1.53; 1.10-2.12), and heart failure (OR = 1.91; 1.06-3.43). CONCLUSION: In contrast to women, adult men with an ASD2 have worse survival than a sex-matched general population. Male patients also have a greater risk of morbidity during adult life. Sex disparity in survival and morbidity suggests the need for a sex-specific clinical approach towards these patients.

Unnatural history of tetralogy of Fallot: prospective follow-up of 40 years after surgical correction.

BACKGROUND: Prospective data on long-term survival and clinical outcome beyond 30 years after surgical correction of tetralogy of Fallot are nonexistent. METHODS AND RESULTS: This longitudinal cohort study consists of the 144 patients with tetralogy of Fallot who underwent surgical repair at <15 years of age between 1968 and 1980 in our center. They are investigated every 10 years. Cumulative survival (data available for 136 patients) was 72% after 40 years. Late mortality was due to heart failure and ventricular fibrillation. Seventy-two of 80 eligible survivors (90%) participated in the third in-hospital investigation, consisting of ECG, Holter, echocardiography, cardiopulmonary exercise testing, N-terminal pro-brain natriuretic peptide measurement, cardiac magnetic resonance (including dobutamine stress testing), and the Short Form-36 questionnaire. Median follow-up was 36 years (range, 31-43 years). Cumulative event-free survival was 25% after 40 years. Subjective health status was comparable to that in the normal Dutch population. Although systolic right and left ventricular function declined, peak exercise capacity remained stable. There was no progression of aortic root dilation. A previous shunt operation, low temperature during surgery, and early postoperative arrhythmias were found to predict late mortality (hazard ratio, 2.9, 1.1, and 2.5, respectively). An increase in QRS duration and a deterioration of exercise tolerance and ventricular dysfunction did not predict mortality. Insertion of a transannular patch was a predictor for late arrhythmias (hazard ratio, 4.0; 95% confidence interval, 1.2-13.4). CONCLUSIONS: Although many patients needed a reoperation or developed arrhythmias, late mortality was low, and the clinical condition and subjective health status of most patients remained good. Previous shunt, low temperature during surgery, and early postoperative arrhythmias were found to predict late mortality.

The additional value of three-dimensional transesophageal echocardiography in complex aortic prosthetic heart valve endocarditis.

BACKGROUND: Two-dimensional transthoracic and transesophageal echocardiography (2DTTE and 2DTEE) may fail to detect signs of prosthetic heart valve (PHV) endocarditis due to acoustic shadowing. Three-dimensional (3D) TEE may have additional value; however, data are scarce. This study was performed to investigate the additional value of 3DTEE for the detection of aortic PHV endocarditis and the extent of the disease process. METHODS: Retrospective analysis of complex aortic PHV endocarditis cases that underwent 2DTTE, 2DTEE, and 3DTEE before surgery. Echocardiograms were individually assessed by 2 cardiologists blinded for the outcome. Surgical and pathological inspection served as the reference standard for vegetations and peri-annular extensions (abscesses/mycotic aneurysms). To determine if the proximal coronary arteries were involved in the inflammatory process as well, computed tomography angiography findings were added to reference standard. RESULTS: Fifteen aortic PHV endocarditis cases were identified. According to the reference standard, all 15 cases had peri-annular extensions, 13 of which had a close relationship with the proximal right and/or left coronary artery. In 6 of 15 patients, a vegetation was present. Combined 2DTTE/TEE missed 1/6 vegetations and 1/15 peri-annular extensions. After addition of 3DTEE, all vegetations (6/6) and peri-annular extensions (15/15) were detected, without adding false positives. Compared to 2DTEE, in 3/15 cases, 3DTEE resulted in better delineation of the anatomical relationship of the proximal coronary arteries to the peri-annular extensions. As a result, 3DTEE had an additional value in 5/15 cases. CONCLUSION: In complex aortic, PHV endocarditis 3DTEE may have additional value compared to 2D echocardiography.

Advances in cardiac magnetic resonance imaging of congenital heart disease.

Due to advances in cardiac surgery, survival of patients with congenital heart disease has increased considerably during the past decades. Many of these patients require repeated cardiovascular magnetic resonance imaging to assess cardiac anatomy and function. In the past decade, technological advances have enabled faster and more robust cardiovascular magnetic resonance with improved image quality and spatial as well as temporal resolution. This review aims to provide an overview of advances in cardiovascular magnetic resonance hardware and acquisition techniques relevant to both pediatric and adult patients with congenital heart disease and discusses the techniques used to assess function, anatomy, flow and tissue characterization.

The natural and unnatural history of the Mustard procedure: long-term outcome up to 40 years.

AIMS: To describe long-term survival, clinical outcome and ventricular systolic function in a longitudinally followed cohort of patients after Mustard repair for transposition of the great arteries (TGA). There is serious concern about the long-term outcome after Mustard repair. METHODS AND RESULTS: This longitudinal single-centre study consisted of 91 consecutive patients, who underwent Mustard repair before 1980, at age <15 years, and were evaluated in-hospital every 10 years. Survival status was obtained of 86 patients. Median follow-up was 35 (IQR 34-38) years. Cumulative survival was 84% after 10 years, 80% after 20 years, 77% after 30 years, and 68% after 39 years. Cumulative survival free of events (i.e. heart transplantation, arrhythmias, reintervention, and heart failure) was 19% after 39 years. Reinterventions were mainly required for baffle-related problems. Supraventricular and ventricular arrhythmias occurred in 28 and 6% of the patients, respectively. Pacemaker and/or ICD implantation was performed in 39%. Fifty survivors participated in the current in-hospital investigation including electrocardiography, 2D-echocardiography, cardiopulmonary-exercise testing, NT-proBNP measurement, Holter monitoring, and cardiac magnetic resonance. Right ventricular systolic function was impaired in all but one patient at last follow-up, and 14% developed heart failure in the last decade. NT-proBNP levels [median 31.6 (IQR 22.3-53.2) pmol/L] were elevated in 92% of the patients. Early postoperative arrhythmias were a predictor for late arrhythmias [HR 3.8 (95% CI 1.5-9.5)], and development of heart failure [HR 8.1 (95% CI 2.2-30.7)]. Also older age at operation was a predictor for heart failure [HR 1.26 (95% CI 1.0-1.6)]. CONCLUSION: Long-term survival after Mustard repair is clearly diminished and morbidity is substantial. Early postoperative arrhythmias are a predictor for heart failure and late arrhythmias.

Common genetic variants improve risk stratification after the atrial switch operation for transposition of the great arteries.

BACKGROUND: Clinical factors are used to estimate late complication risk in adults after atrial switch operation (AtrSO) for transposition of the great arteries (TGA), but heterogeneity in clinical course remains. We studied whether common genetic variants are associated with outcome and add value to a clinical risk score in TGA-AtrSO patients. METHODS AND RESULTS: This multicenter study followed 133 TGA-AtrSO patients (aged 28 [IQR 24-35] years) for 13 (IQR 9-16) years and examined the association of genome-wide single-nucleotide polymorphisms (SNPs) with a composite endpoint of symptomatic ventricular arrhythmia, heart failure hospitalization, ventricular assist device implantation, heart transplantation, or mortality. Thirty-two patients (24%) reached the endpoint. The genome-wide association study yielded one genome-wide significant (p < 1 × 10-8) locus and 18 suggestive loci (p < 1 × 10-5). A genetic risk score constructed on the basis of independent SNPs with p < 1 × 10-5 was associated with outcome after correction for the clinical risk score (HR = 1.26/point increase [95%CI 1.17-1.35]). Risk stratification improved with a combined risk score (clinical score + genetic score) compared to the clinical score alone (p = 2 × 10-16, C-statistic 0.95 vs 0.85). In 51 patients with a clinical intermediate (5-20%) 5-year risk of events, the combined score reclassified 32 patients to low (<5%) and 5 to high (>20%) risk. Stratified by the combined score, observed 5-year event-free survival was 100%, 79% and 31% for low, intermediate, and high-risk patients, respectively. CONCLUSIONS: Common genetic variants may explain some variation in the clinical course in TGA-AtrSO and improve risk stratification over clinical factors alone, especially in patients at intermediate clinical risk. These findings support the hypothesis that including genetic variants in risk assessment may be beneficial.

The prevalence of adult congenital heart disease, results from a systematic review and evidence based calculation.

PURPOSE: The prevalence of adult patients with congenital heart disease (CHD) has been reported with a high degree of variability. Prevalence estimates have been calculated using birth rate, birth prevalence, and assumed survival and derived from large administrative databases. To report more robust prevalence estimate, we performed a systematic review for studies concerning CHD prevalence in adults. Moreover, to diminish bias of calculated estimates, we conducted an evidence-based calculation for the Netherlands. METHODS: A systematic database search was performed to identify reports on the prevalence of adult CHD. Bicuspid aortic valve, mitral valve prolapse, Marfan syndrome, cardiomyopathy, congenital arrhythmia, and spontaneously closed defects were excluded. In addition, CHD prevalence was calculated using birth rate, birth prevalence, and survival estimates. RESULTS: Our search yielded 10 publications on the prevalence of CHD in adults. Four reported results from population wide cross-sectional data, whereas in 6, prevalence was calculated. Mean prevalence reported by empirical studies was 3,562 per million when unspecified lesions were included and 2,297 per million when these were excluded. Mean prevalence derived from calculation was 3,536. Our calculated estimate was 3,228 per million adults. Taking these estimates as well as the limitations inherent to their derivation into consideration, the prevalence of CHD in the adult population is approximately 3,000 per million adults. CONCLUSION: This systematic review presents a comprehensive overview of publications on the prevalence of CHD in adults. The best available evidence suggests that overall prevalence of CHD in the adult population is in the region of 3,000 per million.

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.

Results of balloon dilatation of stenotic homografts in pulmonary position in children and young adults.

OBJECTIVES: To evaluate the results of balloon dilatation of stenotic homografts in children, adolescents, and young adults and to identify factors that might influence or predict the effect of the dilatation. BACKGROUND: Homografts are widely used in congenital cardiac surgery; however, the longevity remains a problem mostly because of stenosis in the homograft. The effect of treatment by balloon dilatation is unclear. METHODS: In a retrospective study, the effect of balloon dilatation was determined by the percentage of reduction of the peak systolic pressure gradient over the homograft during catheterisation and the postponement of re-intervention or replacement of the homograft in months. Successful dilatations - defined in this study as a reduction of more than 33% and postponement of more than 18 months - were compared with unsuccessful dilatations in search of factors influencing or predicting the results. RESULTS: The mean reduction of the peak systolic pressure gradient was 30% in 40 procedures. Re-intervention or replacement of the homograft was postponed by a mean of 19 months. In all, 14 balloon dilatations (35%) were successful; the mean reduction was 49% and the mean postponement was 34 months. The time since homograft implantation, the presence of calcification, the homograft/balloon ratio, and the pressure applied during dilatation all tended to correlate with outcome, but were not statistically significant. CONCLUSIONS: Balloon dilatation is able to reduce the peak systolic pressure gradient over homografts in a subgroup of patients and can be of clinical significance to postpone re-intervention or pulmonary valve replacement.