Introduction Heart failure (HF) is the leading cause of death in adults with a systemic right ventricle (sRV). Dapagliflozin has been shown to reduce hospitalization for HF and all-cause death in patients with HF and reduced ejection fraction. The impact of dapagliflozin in patients with a sRV remains unknown. Objective We aimed to evaluate the efficacy and safety of dapagliflozin in patients with sRV. Methods This was a prospective, observational, single-center study. All symptomatic (NYHA≥2) patients with a sRV dysfunction despite optimal medical treatment were included from March 2023 to March 2024. Patients were assessed at baseline and 3, 6 and 12months after dapagliflozin introduction. The primary endpoint was the 6-minute walk distance. Secondary endpoints included NT-proBNP, quality of life (KCCQ-12), NYHA class, systemic and sub-pulmonary ventricular systolic function, and potential treatment-related side effects. Expected results A total of 32 patients were included. Mean age was 48years (range: 19–79), 20 (62%) of patients were male, 12 (38%) had congenitally corrected transposition of the great arteries and 20 (62%) had transposition of the great arteries with atrial switch. Preliminary results at 6months were available in 20 patients. There was no statistically significant improvement in 6-minute walk distance (558.0m vs. 599.5, P=0.11) nor NT-proBNP (355.5pg/mL vs. 293.5, P=0.81). However, the quality of life of patients (80.5 vs. 92.0, P<0.01) and the right ventricle global longitudinal strain (−11.2% vs. −12.9, P<0.01) significantly improved. The drug was well tolerated with no side effects reported (Fig. 1). Perspectives These preliminary results suggest that dapagliflozin is well tolerated and associated with improved quality of life and right ventricle global longitudinal strain in patients with sRV dysfunction. Final results will bring important data on long-term outcomes associated with dapagliflozin use in this population.

BACKGROUND:In patients with transposition of the great arteries and an arterial switch operation (TGA-ASO) right ventricular outflow tract (RVOT) obstruction is a common complication requiring one or more RVOT interventions. OBJECTIVES:We aimed to assess cardiopulmonary exercise capacity and right ventricular function in patients stratified for type of RVOT intervention. METHODS:TGA-ASO patients (≥16 years) were stratified by type of RVOT intervention. The following outcome parameters were included: predicted (%) peak oxygen uptake (peak VO2), tricuspid annular plane systolic excursion (TAPSE), tricuspid Lateral Annular Systolic Velocity (TV S'), right ventricle (RV)-arterial coupling (defined as TAPSE/RV systolic pressure ratio), and N-terminal proBNP (NT-proBNP). RESULTS:447 TGA patients with a mean age of 25.0 (interquartile range (IQR) 21-29) years were included. Patients without previous RVOT intervention (n = 338, 76%) had a significantly higher predicted peak VO2 (78.0 ± 17.4%) compared to patients with single approach catheter-based RVOT intervention (73.7 ± 12.7%), single approach surgical RVOT intervention (73.8 ± 28.1%), and patients with multiple approach RVOT intervention (66.2 ± 14.0%, p = 0.021). RV-arterial coupling was found to be significantly lower in patients with prior catheter-based and/or surgical RVOT intervention compared to patients without any RVOT intervention (p = 0.029). CONCLUSIONS:TGA patients after a successful arterial switch repair have a decreased exercise capacity. A considerable amount of TGA patients with either catheter or surgical RVOT intervention perform significantly worse compared to patients without RVOT interventions.

In native aortic coarctation, as well as recoarctation with appropriate anatomy, stenting has become the treatment of first choice according to European guidelines. The objective of this study was to assess the safety as well as the short and long-term efficacy of percutaneous treatment of aortic coarctation/recoarctation in adults. This study included all adult patients with a native or post-operative aortic coarctation treated percutaneously in a single center from March 2006 to December 2022. Baseline characteristics, intra-procedural and follow-up data were analyzed. The primary outcome was acute procedural success and secondary outcomes were intra-operative and late complications. A total of 62 patients were included. The mean age was 35 years (range, 15–74), 33 (53.2%) patients were male. Thirty patients (48.3%) had a native aortic coarctation, 57 (91.9%) were hypertensive and 32 (51.6%) had a bicuspid aortic valve. Acute procedural success was achieved in all patients with a peak-to-peak gradient at the end of the procedure lower than 20 mmHg in 60 (96.7%) patients. Two (3.2%) patients had a non-fatal aortic rupture without sequelae and 2 (3.2%) had a false femoral aneurysm requiring intervention. At the follow-up visit, 55.3% patients had persistent arterial hypertension requiring medical treatment. Regarding late complications, 3 (4,8%) patients had aortic recoarctation that required a new percutaneous procedure, 1 (1,6%) patient had a type B aortic dissection that did not require invasive management, and 1 (1,6%) patient had a thrombosis of the right external iliac artery. Percutaneous treatment with stenting of aortic coarctations in adults is safe and effective when performed in expert centers. Follow-up of this cohort will bring important data on very long-term outcomes associated with this technique.

Pregnancies in patients with a Fontan circulation are high-to very high-risk pregnancies. European and American recommendations consider patients with any Fontan complications should be counseled against becoming pregnant. This study sought to evaluate maternal complications in patients with Fontan circulation according to the modified WHO (mWHO) classification. We performed a retrospective observational cohort study across 13 international centers. Maternal and fetal outcomes were reviewed according to baseline risk assessed as per the mWHO classification. Women with oxygen saturations < 85%, NYHA functional class IV, depressed ventricular function, moderate to severe atrioventricular valve regurgitation, refractory arrhythmia, plastic bronchitis, or protein-losing enteropathy (PLE) were considered at very high risk of complications (mWHO IV), those without any Fontan complication were classified at high risk (mWHO III). The risk of remaining patients who experienced other types of Fontan complications was classified as mWHO III–IV. We analyzed 84 women (median age 27 years, interquartile range 23-30) with Fontan physiology undergoing 108 complete pregnancies, average gestation of 33 ± 5 weeks. Fifty-two (48%) pregnancies were classified as mWHO III, 45 (42%) mWHO III–IV, and 11 (10%) mWHO IV (Table 1). None patients had a previous history of PLE or plastic bronchitis. There was no maternal death. Cardiovascular complications occurred in 13 (25%), 16 (35%) and 4 (36%) pregnancies classified mWHO III, III–IV, and IV respectively (P = 0.74). Cardiovascular complication rates remained not significantly different when patients with any Fontan complications were compared to patients without (36% vs. 25%, P = 0.23; Table 1). There were high rates of fetal (n = 73, 68%) and obstetrical (n = 75, 69% including 38 bleeding events) complications without significant difference between the 3 risk groups. Maternal cardiovascular complications occurred in one-third of pregnancies whatever the mWHO classification. Even if there is no reported maternal death, women with Fontan circulation should be carefully counseled on pregnancy risks.

The risk of cancer in adults with congenital heart disease (ACHD) is 23% higher than in the general population. The objective of our study was to assess cancer screening coverage in ACHD. This was a prospective, observational, bicentric study of ACHD patients. Data were collected through a self-questionnaire proposed to all consecutive patients over 25 years from September 2022 to March 2023. Information on cervical, breast and colorectal cancer screening was collected and compared with screening data provided by Santé Publique France. A total of 263 patients were included. The mean age was 44 years (range, 25–78), 122 (46%) patients were male, and 99 (38%) patients had a complex CHD. Eleven (4%) patients had a history of cancer. The screening participation rate for breast cancer was higher in ACHD patients (72%) compared to the general population from Ile de France region (39%, P < 0.001) and from the whole French population (51%, P = 0.002). For colorectal and cervical cancers, the screening participation rate were 36% and 65%, compared to 31% and 51% in Île de France region and 34% and 59% in the whole French population, respectively with no statistically significant difference (Figure 1). Cancer screening coverage in ACHD patients was greater than non-congenital patients for breast cancer, but comparable for colorectal and cervical cancers. The screening participation rate remained however lower than European objectives for all cancers. Our data call for specific actions to better screen this aging population at high risk for cancer.

Abstract Background The arterial switch operation (ASO) is the current technique of choice for the repair of the transposition of the great arteries (d-TGA). Its main advantage is that the left ventricle (LV) sustains the systemic circulation, thus diminishing the risk of late systolic dysfunction as seen in the atrial switch technique. Purpose To study the systolic LV performance in a large cohort of adult patients after ASO and to explore clinical determinants of reduced left ventricular systolic function (LVSF). Methods EPOCH-ASO is an ongoing prospective, multicentre, international cohort study involving 11 reference centres from 5 different countries, that includes adult d-TGA patients after ASO. We conducted a cross-sectional analysis of clinical and echocardiographic data from all patients enrolled in EPOCH-ASO. LVSF was considered reduced when ejection fraction (EF) by Simpson’s method was < 54% in women or <52% in men, or by visual assessment when EF could not be obtained. Results 513 patients have been included in EPOCH-ASO, with a median age of 25.3 years [IQR: 21 – 28 years] at the time of enrolment. At baseline, 41% had history of at least one reintervention (23.2% at the right ventricular outflow tract (RVOT), 5.1% at the left ventricular outflow tract (LVOT), 4.5% at the aortic arch, 3.3% pacemaker implantation). Echocardiographic data were obtained in 450 patients (88 % of the total cohort). Left ventricular ejection fraction (LVEF) by biplane Simpson method was available in 316 patients (mean LVEF 58.3 ± 7.2%), while visual assessment of LVSF was performed in 134 patients. For the total cohort with echocardiographic data available, 62 (13.8%) had a reduced LVSF. Global longitudinal strain (GLS) analysis was available in 145 patients (28.2% of the total cohort), with a mean value of -17.4% ±2.7%. GLS was impaired (>-18%) in 53% of the patients. Furthermore, 48% of the 117 patients with normal LVEF had a reduced GLS. Older age at the time of the echocardiography, late repair (>12th day), a previous pulmonary banding or having a pacemaker implanted were factors associated with an impaired LVSF. In the multivariate analysis, age at the time of the echocardiography (OR 1.06 per year, CI 1.01-1.12; p<0.001) and late repair (OR 1.85, CI 1.11-3.06, p=0.03) remained significant. As for the speckle tracking analysis, a significantly lower GLS was found in patients after LVOT intervention (-15% vs -17.6%, p=0.005) and with a neo-aortic root above the median (37.5 mm) (GLS -17% vs -18%, p=0.03). In the multivariate analysis only LVOT intervention remained significant (p=0.016). Conclusions Left ventricular systolic dysfunction is not exceptional in patients after ASO and it may become a concern as this population ages. Speckle tracking analysis might identify earlier stages of ventricular dysfunction. Large comprehensive longitudinal studies are needed to better characterize the left ventricular systolic function in this patient population.

The extent and significance of cardiac remodeling in Fontan patients are unclear. The aim of this study was to measure myocardial fibrosis in single ventricle (SV) and to determine its relationship with Fontan failure. A prospective cross-sectional study was performed in 25 patients (mean age 32 ± 9 years, 48% male) with SV. Echocardiography, cardiopulmonary exercise test, BNP measurement and cardiac magnetic resonance imaging (CMR) were performed within the same day. Assessment of late gadolinium enhancement in combination with T1 mapping to quantify diffuse myocardial fibrosis with assessment of myocardial extracellular volume (ECV) were performed. Associations between parameters of SV remodeling, BNP and exercise performances were evaluated. Ten patients (40%) showed clinical signs of Fontan failure. SV volumes and mass were significantly increased in these patients compared to asymptomatic patients (P < 0.01), while there was no difference in SV ejection fraction. Compared to asymptomatic Fontan patients, those with failing Fontan had significantly higher native T1 (1030 ± 29 ms vs. 982 ± 25 ms, P < 0.001) and ECV (32% (interquartile range (IQR) 30–36) vs. 27% IQR [25–30], P = 0.002). Amongst CMR parameters, only native T1 was significantly correlated with the peak VO2 [r = −0.49, P = 0.017] and BNP (r = 0.41, P = 0.046). No association was observed with echocardiographic parameters of SV systolic and diastolic function. Diffuse myocardial fibrosis is a determinant of Fontan circulation failure independently of systolic ventricular function.

We aimed to evaluate the safety and efficacy of non-vitamin K antagonist oral anticoagulants (NOACs) in adults with congenital heart disease (CHD) who underwent a pulmonary valve replacement (PVR). This is an international, multicenter, prospective study using data from the NOTE registry. All adults with a history of PVR taking NOACs constituted our study population. Follow-up took place at 6 months and yearly thereafter. The primary endpoint were thromboembolic (TE) events and major bleeding (MB). The secondary endpoint was minor bleeding. From January 2013 to June 2021, 29 patients (median age 52 years, interquartile range [43–58], 58% male) with a history of PVR (59% moderately and 31% severely complex CHD) on NOACs were included in the NOTE registry and constituted our study population. Atrial arrhythmia was the exclusive indication for anticoagulant therapy. During a median follow-up of 2 years (IQR 0.8–3.2), no patient experienced TE event. One MB (3.5%) which led to death and 6 minor bleedings (20.7%) occurred on NOACs alone (Fig. 1). The annual incidence rate was 1.6% (95% CI 0.04 to 9.2%) for MB and 8.4% (96% CI 2.7 to 19.6%) for minor bleeding. The overall survival free from TE and MB was 100% and 87.5% respectively at 2.5 years of follow-up. Three invasive cardiac procedures, including 2 percutaneous PVR, were safely performed during the follow-up. On univariate analysis, increase in BLED score (HR 3.5; 95% CI 1.2–10.2, P = 0.02) and female gender (HR (male) 0.08; 95% CI 0.01–0.7; P = 0.02) were predictive factors of bleeding. This prospective study demonstrated excellent efficacy of NOACs at mid-term in patients with CHD and PVR, but suggested an increased risk of bleeding, particularly in women and patients with high BLED score.

A substantial number of patients experiences late Fontan circulation failure. Previous concepts of Fontan failure implicate increasing pulmonary vascular resistance (PVR) as a key contributor to late circulatory failure. However, data to support this assumption are sparse. We sought to characterize hemodynamic findings in adult failing Fontan patients. We performed a bicentric retrospective cohort study in adult Fontan patients, identifying patients with Fontan failure. Patients were divided into systolic dysfunction (rEF) when ejection fraction (EF) < 40%, diastolic dysfunction (pEF) when EF ≥ 40% with systemic ventricular end-diastolic pressure ≥ 12 mmHg or elevated BNP level (> 200 pg/mL) and pulmonary hypertension (PH) when indexed pulmonary vascular resistance were elevated (≥ 2 WU*m2). Hemodynamic, echocardiographic, and clinical data were recorded. Between 2000 and 2021, 55 adult patients were diagnosed with failing Fontan. Median age at diagnosis was 27 years (interquartile range (IQR), 22–30.7) i.e., 18.0 years [12.0–23.0] after Fontan surgery. The main hemodynamic cause of failing Fontan was the dysfunction of the systemic ventricle in 25 patients (45%), including 15 rEF and 10 pEF without additional hemodynamic lesions. PH was diagnosed in 6 (11%) patients and was isolated in 4 of them. Nine patients (16%) exhibited significant valvular dysfunction and 6 (11%) conduit stenosis. During a median FU of 5 years [1.25–12], Fontan failure-associated morbidity (33/55; 60%) and mortality (6/55, 11%) were substantial regardless of underlying hemodynamic lesions. Dysfunction of the systemic ventricle, systolic and/or diastolic, is frequent feature in late Fontan failure in adults, while increases in PVR were rarely observed. The intricate interplay between hemodynamic compromises in Fontan failure deserves further research to optimize treatment strategies and outcome.

Abstract Introduction One year after the beginning of the Coronavirus Disease 2019 (COVID-19) pandemic, the evidence on outcomes among adults with congenital heart disease (ACHD) is still limited. Purpose We aimed to compare patient characteristics and outcomes between the first and the subsequent COVID-19 waves and to identify overall predictors for complicated disease course among ACHD patients. Methods We collected reported COVID-19 cases among ACHD patients followed at 26 tertiary care centers in 10 European countries between March 27, 2020 and March 25, 2021. Patient characteristics, heart defect complexity and residual problems, medical history, date of diagnosis and course and outcome of COVID-19 were recorded. Cases were stratified into first vs. subsequent COVID-19 waves (cut-off date July 15, 2020). A complicated disease course was defined as hospitalization for COVID-19 requiring ventilation and/or inotropic support, extracorporeal membrane oxygenation or death. Data were reported as median (interquartile range) and counts (percentage). Results Overall, 548 cases were included (first wave: n=161; subsequent waves: n=387). Median age 33 (26–44) years, 52% female. Thirty-three patients (6%) had a complicated disease course. Between waves (first vs. subsequent), there were no statistically significant differences related to gender (women 57% vs. 49%, p=0.09), body mass index (BMI) category (p=0.7), heart defect complexity (p=0.08) and residual heart defect-related problems (p=0.6). Patients in the first wave were older, had more often ≥2 comorbidities and a complicated disease course (37 vs 33 years, p=0,001; 17% vs. 7%, p=0.0003; and 9% vs. 5%, p=0.04, respectively). The proportion of deaths did not significantly differed between waves (4% vs 2%, p=0.2). A detailed comparison of the above-reported characteristics is depicted in table 1. From multivariable models, adjusted odds ratios (OR) (95% confidence interval) for the prediction of complicated COVID-19 course are depicted in table 2. Main independent predictors for a complicated disease course were: cyanotic heart disease, including unrepaired cyanotic defects or severe pulmonary hypertension with Eisenmenger syndrome (OR 8.49 [3.14–22.94], p<0.001), BMI >25 kg/m2 (OR 3.91 [1.62–9.43], p=0.002), having ≥2 comorbidities (OR 2.63 [1.05–6.62], p=0.04) and age per five years (OR 1.21 [1.05–1.42], p=0.01). Conclusion Complicated COVID-19 course among ACHD patients is rare. Outcomes in the first wave were worse when compared to subsequent waves, mainly because patients of the first wave were older and had more comorbidities. Age, cyanotic heart disease (including unrepaired cyanotic defects or severe pulmonary hypertension with Eisenmenger syndrome), having ≥2 comorbidities and a BMI >25 kg/m2 were the main predictors for a complicated disease course. Funding Acknowledgement Type of funding sources: None.

Abstract Introduction Partial anomalous pulmonary venous connection (PAPVC) is a rare congenital heart disease, which is characterized by one or some but not all pulmonary veins anomalously connected to the right atrium or a systemic vein. PAPVC is either an isolated shunt lesion or associated with an atrial septal defect (ASD). The only curative treatment is surgery, however the indication for surgery can be challenging. This study compares the outcome of patients treated surgically with those clinically monitored. Method Clinical, surgical, imaging and invasive data were retrospectively reviewed from 7 centers from the Swiss Adult Congenital HEart Registry (SACHER) and a French center. Results A total of 168 patients with partial anomalous pulmonary venous connection were identified. The majority (77%) of patients underwent surgery and the remaining (23%) were treated conservatively with clinical monitoring. The operated group (OG) had a significantly higher proportion of associated ASD (N=106, 82%) (p<0.001) and a higher prevalence of anomalous pulmonary veins leading to a mean Qp:Qs at 2.5±1.2 before surgery. Latest follow-up was 12 years after surgery. Mean age was 40±17 years. Patients in the non-operated group (NOG) were significantly more dyspneic than the OG (p=0.002). However, the need for medical treatment did not differ between groups: 58% of the NOG and 48% in the OG (p=0.203). Right ventricular (RV) ejection fraction did not differ between groups despite a significantly larger RV end-diastolic volume and a higher Qp:Qs on cardiac magnetic resonance (CMR) in the NOG (table). On echocardiography, the NOG showed a significantly better right ventricular longitudinal function and a higher systolic pulmonary artery pressure than the OG (table). The prevalence of significant valvulopathies did not differ between groups (table). Both groups had normal exercise capacity and with no differences between groups (table). Eighteen (14%) OG patients required a re-intervention either for residual shunt and/or stenosis of the pulmonary veins, superior and inferior vena cava. Conclusion PAPVC patients after surgical correction, show a favorable outcome in terms of imaging parameters and exercise capacity, however, a significant number presents with symptoms. PAPVC patients treated conservatively with small left to right shunting, have similar outcome justifying a conservative approach. Funding Acknowledgement Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Unrestricted grant from Actelion, Switzerland

BACKGROUND:Children with repaired congenital heart disease (CHD) have impaired maximal aerobic capacity (VO2max). Determining the causes of their VO2max alteration remains challenging. Cardiac output measure using thoracic impedancemetry during cardiopulmonary exercise tests (CPET) can help to understand the determinants of VO2max in children with open-heart repaired CHD.METHOD:We analyzed CPET in 77 children with repaired CHD. Among them, 55 patients had residual lesions. Patients with repaired CHD were compared with 44 age-matched healthy individuals. Maximal oxygen content brought to capillaries (QO2max) and oxygen muscle diffusion capacity (DO2) were assessed using cardiac output measure, Fick principle and simplified Fick law.RESULTS:In the 55 patients with residual lesion, VO2max, QO2max and DO2 were lower than those of controls (76.1 vs 86% of theoretical value, p < 0.01; 2.15 vs 2.81 L/mn, p < 0.001; 24.7 vs 28.8 ml/min/mmHg, p < 0.05). Decrease in QO2max was due to both impaired stroke volume and chronotropic insufficiency (48 vs 53 ml/m2 and p < 0.05; 171 vs 185/min p < 0.001). Patients without residual lesion (22/77) had normal VO2max with lower maximal heart rate compensated by higher SV (p < 0.05).CONCLUSION:Aerobic capacity was normal in children without residual lesions after CHD repair. Patients with residual lesion have impaired VO2max due to both lower central and peripheral determinants. Measuring cardiac performance during CPET allowed a better selection of patients with altered cardiac reserve that can benefit from residual lesion treatment and find the good timing for intervention. Detection of peripheral deconditioning can lead to a rehabilitation program.

In complete transposition of the great arteries (TGA) palliated by atrial switch operation, systemic right ventricle (sRV) failure and rhythm disturbances compromise survival. We aimed to determine predictive factors of severe cardiovascular events in this population. Forty-eight adult patients with TGA palliated (36 males, median age = 32 years, IQR [23–35]) were prospectively enrolled from 2011 to 2012. At baseline, all subjects underwent a clinical examination with ECG and exercise test, an echocardiography, a cardiac magnetic resonance imaging (cMRI) assessment and biomarkers measurements. Main adverse cardiac events (MACE) were defined by hospitalization for heart failure, arrhythmia, heart transplantation and death. At baseline, most of patients were asymptomatic (85% NYHA1, median predictive VO2 = 66% IQR [58–73]), with a relatively good sRV function (cMRI sRVEF = 52% IQR [44-58]), and tricuspid regurgitation grade was mild in 87%. Baseline concentration of BNP was 34 pg/ml (IQR [14-54]) but higher than in controls ( P < 0.01), as well as myocardial collagen biomarkers concentrations (pro-MMP1 and P3NP, P < 0.05). After a mean follow-up period of 7 ± 0.3 years, 9 MACE occurred (2.7% patient-years) 4 patients experienced HF, 4 atrial arrhythmia and 1 ventricular tachycardia. 2 patients were transplanted and none death was observed. Among baseline characteristics, NYHA functional class ≥ 2 (HR = 5.17 95%CI [1.37–19.59], P = 0.04), end-diastolic and end–systolic sRV volumes ( P ≤ 0.02) and BNP (HR = 1.02 95%CI [1.00–1.03], P = 0.01), were significantly predictive of MACE. Cumulative incidence of MACE in patients with NYHA functional class ≥ 2 or BNP≥150 pg/mL was 43% to 2 years compared to 5% in patients without ( Fig. 1 ). Patients with a TGA palliated by atrial switch are at high risk of severe cardiovascular events. Increase in NYHA functional class and BNP concentration must be regularly controlled to detect patients at risk.

Central illustration. Evolution of acute procedural success rates. Partial acute procedural success was defined as termination of clinical arrhythmia with subsequent verification of bidirectional conduction block with additional arrhythmias induced not targeted or not successfully targeted or absence of final programmed stimulation performance. Complete acute procedural success was defined as termination of clinical arrhythmia(s) with subsequent verification of bidirectional conduction block and non-inducibility of other arrhythmias or successful ablation of all secondary arrhythmias induced (except inducible atrial fibrillation [AF]). Final programmed stimulation performance was not required to consider complete acute procedural success when the targeted arrhythmia was AF, premature ventricular contraction or atrioventricular node. The red line represents the rate of final programmed stimulation. FAT: focal atrial tachycardia; IART: intra-atrial reentrant tachycardia.

Abstract Background The arterial switch operation (ASO) has replaced atrial switch procedures for D-transposition of the great arteries (D-TGA), with 90% of patients now reaching adulthood. However, patients may have residual lesions and/or sequelae, some of which may remain unrecognized, necessitating lifelong specialist surveillance. We examined the cardiac outcomes of a large number of contemporary ASO patients under tertiary adult congenital heart disease (ACHD) care. Methods We examined late major adverse cardiovascular events (MACE) in adult TGA patients (>16 years) who underwent an ASO between 1981 and 2003 and continued their follow-up in 2 tertiary ACHD centers. MACE were defined as death, re-intervention, myocardial ischemia, arrhythmia, stroke/TIA, infective endocarditis and heart failure. Results Overall, 199 patients (66% male, mean age 27±5 years) were followed in adult life for a median of 10 years [IQR 7–15] and were included in this study. Overall survival during this period was 99.5% (95% confidence interval [CI]: 94.4%-99.8%). Sixty-two (31.2%) patients experience MACE, including 52 reinterventions. MACE and reintervention-free survival at 20, 30 and 35 years were 87.6%, 58.6%, 50.6% and 89.5%, 69.1, 61%, respectively. Atrial arrhythmia was the most frequent cardiac event with an incidence of 5.5 cases per 1000 patient-years, whereas incidence of ventricular tachycardia and sudden cardiac death was 1.8‰ and 0.9‰ patient-years, respectively. Coronary artery disease was diagnosed in 6 (3%) patients, of whom 4 had symptoms, 1 had ST depression on ECG at rest and 3 had abnormal wall motion on echocardiography. The most frequent indication for reoperation was right ventricular outflow tract obstruction (n=35/52, 63.7%), whereas left ventricular outflow tract (LVOT) re-interventions rate increased significantly during adulthood compared to childhood from 1% to 5%, p=0.03 (Figure 1). On multivariate analysis, history of cardiac complications during infancy (HR 2.3, 95% CI:1.3–4.0, p<0.01) and uncommon coronary patterns (HR for type A versus B/C/D/E 0.47, 95% CI:0.26–0.83, p<0.01) were independent predictors of MACE in adulthood. At the latest follow-up, 90.9% of patients were functional class I, left ventricular ejection fraction was 59.6±6.5% and peak oxygen uptake 71.1±24.9% predicted. At least moderate neoaortic regurgitation and aortic dilatation (≥40mm) were present in 8.0% and 35.2%, respectively, with more than mild pulmonary stenosis in 19.6%. Conclusion Adult patients with ASO for TGA have a low late mortality. However, MACE are common requiring reintervention, particularly for RVOT obstruction and neo-aortic valve dysfunction, the latter with rising rates during adulthood. Patients with cardiovascular complications during childhood are at the highest risk for MACE. All patients merit life-long tertiary care. Figure 1 Funding Acknowledgement Type of funding source: Public hospital(s). Main funding source(s): Assistance Publique des Hôpitaux de Paris

Abstract Introduction Total anomalous pulmonary venous connection is a rare cyanotic congenital heart disease, where all pulmonary veins aberrantly connect to a systemic vein or the right atrium. The only curative treatment is surgery allowing the patients to reach adulthood. This study describes the long-term outcome of these individuals focusing on arrhythmias. Methods Clinical, surgical, imaging and invasive data were retrospectively reviewed from 7 centers participating in the Swiss Adult Congenital Heart disease Registry (SACHER) and one French center. Results A total of 57 patients were identified and analyzed 22±8 years after surgery. At last follow-up, 21% of patients presented cardiac symptoms, mainly palpitations. No patient had pulmonary hypertension or a relevant valvulopathy. Echocardiography revealed in 5 (8.8%) patients a dilated right ventricle (RV) and in 3 (5.3%) patients a diminished RV systolic function. Exercise capacity was normal in most patients (table). Cardiac magnetic resonance imaging found in 2 (4%) had a residual shunt with an mean Qp:Qs of 1.25, due to a single anomalously connected pulmonary vein. Holter recordings revealed arrhythmias in 23% of patient. Ten (17.5%) had atrial fibrillation, flutter or tachycardia. Three (5%) patients presented ventricular arrhythmias: two patients showed non-sustained ventricular tachycardia and one patient complex ventricular extrasystoles. Four patients (7%) were on antiarrhythmic medication for supraventricular arrhythmias. Three patients (5%) underwent an electrophysiological study with a mean time since surgery of 20 years. Three (5%) patients underwent pacemaker implantation within 3 weeks to 36 months after surgical correction, which were removed in 2 patients after 7 years. Age and the presence of a valvulopathy at follow-up predicted tachyarrhythmia on binomial logistic regression analysis (p<0.03). Conclusions In adult survivors after TAPVC repair, supraventricular but also ventricular arrhythmias are frequently observed which appears to be related to age and valvular lesions at follow-up. This study underlies the importance of long-term follow-up as some of the patients currently without arrhythmia will probably develop rhythm disorders in the future. Funding Acknowledgement Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Unrestricted grant by Actelion SA, Switzerland