The relationship between perceived parenting practices and anxiety in adults with congenital heart disease.

BACKGROUND: Patients with congenital heart disease (CHD) and their parents face challenges throughout their lives that can lead to anxiety lasting into adulthood. We aim to assess the association between perceived parenting practices and anxiety beyond pediatric medical-surgical histories in adults with CHD. METHODS: A cross-sectional study of adults with CHD was conducted at the Montreal Heart Institute (MHI). Perception of parental practices during childhood was retrospectively assessed using validated self-report questionnaires, while anxiety in adulthood was assessed with the Hospital Anxiety and Depression Scale (HADS). Sociodemographic and medical information were collected from a questionnaire and medical records. Hierarchical multiple linear regression was conducted. RESULTS: Of the 223 participants, 59% were female, and the mean age was 46 ± 14 years. Perceived parenting practices explained more variance (11%) in the anxiety score than pediatric medical-surgical history (2%). In our final model, anxiety was significantly associated with age, parental history of anxiety, and positive parenting practices, but not with overprotection. CONCLUSIONS: Parenting practices are associated with anxiety in adults with CHD beyond pediatric medical-surgical history and sociodemographic. Positive parenting practices may be protective against anxiety in adulthood. Longitudinal studies are needed to determine causality.

Pulmonary vascular disease and optical coherence tomography imaging in patients with Fontan palliation.

INTRODUCTION: The Fontan procedure is the palliative procedure of choice for patients with single ventricle physiology. Pulmonary vascular disease (PVD) is an important contributor to Fontan circulatory failure. AREAS COVERED: We review the pathophysiology of PVD in patients with Fontan palliation and share our initial experience with optical coherence tomography (OCT) in supplementing standard hemodynamics in characterizing Fontan-associated PVD. In the absence of a sub-pulmonary ventricle, low pulmonary vascular resistance (PVR; ≤2 WU/m2) is required to sustain optimal pulmonary blood flow. PVD is associated with adverse pulmonary artery (PA) remodeling resulting from the non-pulsatile low-shear low-flow circulation. Predisposing factors to PVD include impaired PA growth, endothelial dysfunction, hypercoagulable state, and increased ventricular end-diastolic pressure. OCT parameters that show promise in characterizing Fontan-associated PVD include the PA intima-to-media ratio and wall area ratio (i.e. difference between the whole-vessel area and the luminal area divided by the whole-vessel area). EXPERT OPINION: OCT carries potential in characterizing PVD in patients with Fontan palliation. PA remodeling is marked by intimal hyperplasia, with medial regression. Further studies are required to determine the role of OCT in informing management decisions and assessing therapeutic responses.

Impact of Fontan Fenestration on Adverse Cardiovascular Outcomes: A Multicentre Study.

BACKGROUND: Fenestrating a Fontan baffle has been associated with improved perioperative outcomes in patients with univentricular hearts. However, longer-term potential adverse effects remain debated. We sought to assess the impact of a fenestrated Fontan baffle on adverse cardiovascular events including all-cause mortality, cardiac transplantation, atrial arrhythmias, and thromboemboli. METHODS: A multicentre North American retrospective cohort study was conducted on patients with total cavopulmonary connection Fontan baffle, with and without fenestration. All components of the composite outcome were independently adjudicated. Potential static and time-varying confounders were taken into consideration, along with competing risks. RESULTS: A total of 407 patients were followed for 10.4 (7.1-14.4) years; 70.0% had fenestration of their Fontan baffle. The fenestration spontaneously closed or was deliberately sealed in 79.9% of patients a median of 2.0 years after Fontan completion. In multivariable analysis in which a persistent fenestration was modelled as a time-dependent variable, an open fenestration did not confer a higher risk of the composite outcome (hazard ratio, 1.18; 95% confidence interval, 0.71-1.97; P = 0.521). In secondary analyses, an open fenestration was not significantly associated with components of the primary outcome: that is, mortality or transplantation, atrial arrhythmias, or thromboemboli. However, sensitivity analyses to assess the possible range of error resulting from imprecise dates for spontaneous fenestration closures could not rule out significant associations between an open fenestration and atrial arrhythmias or thromboemboli. CONCLUSIONS: In this multicentre study, no significant association was identified between an open fenestration in the Fontan baffle and major adverse cardiovascular events.

Design of the Prospective Comparison of Angiotensin Receptor-Neprilysin Inhibitor Versus Placebo in Patients With Congenital Systemic Right Ventricle Heart Failure (PARACYS-RV) Trial.

The presence of a systemic right ventricle (sRV) with biventricular physiology (biV) is associated with increased patient morbidity and mortality. To date, no pharmacologic therapy for heart failure has been proven effective for patients with systolic dysfunction of the sRV-biV. We designed a randomized, double-blind, placebo-controlled crossover trial to compare sacubitril/valsartan treatment to placebo in adults (aged ≥ 18 years) with moderate-to-severe sRV-biV dysfunction and New York Heart Association functional class II to III symptoms. Two primary efficacy endpoints are assessed in the trial: exercise capacity (submaximal exercise duration) and neurohormonal activation (N-terminal prohormone brain natriuretic peptide). Secondary objectives include assessing a change in the Kansas City Cardiomyopathy Questionnaire score and evaluating the safety and tolerance of sacubitril/valsartan. A 6-week open run-in phase identifies the maximum tolerated dose of sacubitril/valsartan, up to 97 mg/103 mg twice daily. After a 2-week washout period, patients are randomized 1:1 to sacubitril/valsartan treatment vs placebo for a 24-week phase, followed by another 2-week washout period and subsequent crossover to the alternative treatment arm for an additional 24-week phase. Data to assess primary and secondary endpoints are collected at baseline and at the end of each phase. A total of 48 patients is required to provide > 80% power to detect a 30% difference in distance walked and in N-terminal prohormone brain natriuretic peptide levels with sacubitril/valsartan treatment vs placebo, each with a 2-sided P-value of 0.025. In summary, the Prospective Comparison of Angiotensin Receptor-Neprilysin Inhibitor vs Placebo in Patients With Congenital Systemic Right Ventricular Heart Failure Trial (PARACYS-RV) should determine the role of sacubitril/valsartan in treating heart failure in patients with sRV-biV and carries the potential to alter management of this patient population.

La présence d'un ventricule droit systémique (VDs) avec physiologie biventriculaire (PbiV) est associée à une morbidité et une mortalité accrues chez les patients. À ce jour, aucune pharmacothérapie de l'insuffisance cardiaque ne s'est révélée efficace chez les patients atteints d'une dysfonction systolique du VDs-PbiV. Nous avons conçu un essai croisé, à répartition aléatoire et à double insu, contrôlé par placebo pour comparer la bithérapie sacubitril-valsartan au placebo chez les adultes (≥ 18 ans) ayant une dysfonction modérée ou sévère du VDs-PbiV et des symptômes de la classe fonctionnelle II à III de la New York Heart Association. Deux paramètres d'évaluation principaux de l'efficacité sont définis pour l'essai : tolérance à l'effort (durée d'effort sous-maximal) et activation neurohormonale (propeptide natriurétique de type B N-Terminal [NT-proBNP]). La mesure d'une variation du score au questionnaire sur la cardiomyopathie de Kansas City de même que l'évaluation de l'innocuité et de la tolérance de la bithérapie sacubitril-valsartan sont des objectifs secondaires. Une phase préparatoire de six semaines en mode ouvert permet d'établir la dose maximale tolérée de sacubitril-valsartan, jusqu'à concurrence de 97 mg/103 mg deux fois par jour. Après une période de repos thérapeutique de deux semaines, les patients sont affectés au hasard, dans un rapport 1:1, à la bithérapie sacubitril-valsartan ou au placebo pendant une phase de traitement de 24 semaines, suivie d'une autre période de repos thérapeutique de deux semaines et d'un passage subséquent à l'autre groupe de traitement pendant une phase additionnelle de 24 semaines. Les données sur les paramètres d'évaluation principaux et secondaires sont recueillies au début de l'essai et à la fin de chaque phase. Il faut un total de 48 patients afin d'obtenir une puissance supérieure à 80 % pour détecter une différence de 30 % entre la bithérapie sacubitril-valsartan et le placebo quant à la distance parcourue à la marche et aux taux de NT-proBNP, la valeur p bilatérale étant de 0,025 pour les deux valeurs. En résumé, l'essai PARACYS-RV (Prospective Comparison ofAngiotensinReceptor-Neprilysin Inhibitor vs Placebo in Patients WithCongenital SystemicRightVentricular Heart Failure) doit déterminer le rôle de la bithérapie sacubitril-valsartan dans le traitement de l'insuffisance cardiaque chez les patients ayant un VDs-PbiV et pourrait modifier la prise en charge de cette population de patients.

Time in Therapeutic Range With Vitamin K Antagonists in Congenital Heart Disease: A Multicentre Study.

BACKGROUND: Vitamin K antagonists (VKAs) are frequently prescribed to patients with congenital heart disease (CHD) for atrial arrhythmias or Fontan palliation, but there is a paucity of data regarding time spent in the therapeutic range (TTR). We sought to determine the TTR in patients with CHD and atrial arrhythmias or Fontan palliation prescribed VKAs and explore associations with thromboembolic and bleeding events. METHODS: A multicentre North American cohort study was conducted on patients with CHD who received VKAs for sustained atrial arrhythmia or Fontan palliation. TTR was calculated using the Rosendaal linear interpolation method. Generalized estimating equations were used to explore factors associated with time outside the therapeutic range. RESULTS: A total of 567 patients, aged 33 ± 17 years, 56% female, received VKAs for 11.5 ± 8.4 years for atrial arrhythmias (63.0%) or Fontan palliation (58.0%). CHD was simple, moderate, and complex in 10.8%, 20.3%, and 69.0%, respectively. Site investigators perceived good control over international normalized ratio (INR) levels in most patients (75.3%), with no or minor compliance or adherence issues (85.6%). The mean TTR was 41.9% (95% confidence interval [CI], 39.0%-44.8%). Forty-seven (8.3%) and 34 (6.0%) patients had thromboembolic and bleeding events, respectively. Thromboembolic events were associated with a higher proportion of time below the therapeutic range (31.3% vs 19.1%, P = 0.003) and bleeding complications with a higher proportion of time above the therapeutic range (32.5% vs 19.5%, P = 0.006). CONCLUSIONS: Patients with CHD who receive VKAs spend < 42% of their time with INR levels in the therapeutic range, with repercussions regarding thromboembolic and bleeding complications.

The Fontan Circulation: From Ideal to Failing Hemodynamics and Drug Therapies for Optimization.

Fontan palliation results in a hemodynamically complex circulation with multisystem consequences, which in the long term adversely affect many body processes. Systemic venous hypertension, nonpulsatile low-shear pulmonary blood flow, and low cardiac output are the 3 main characteristics of a Fontan circulation, leading to unavoidable slowly progressive failure. An appreciation of how the hemodynamics of a Fontan circulation change with time and relate to the various modes of Fontan circulatory failure is important. Accurate hemodynamic assessment aid this understanding and may permit early identification of potentially treatable drivers of decline. While no evidence-based or guideline-directed pharmacologic management strategy has been established in Fontan patients, understanding the hemodynamics of Fontan circulation failure will assist in the rational selection of potentially helpful drug therapies for individual patients. In this review, we present hemodynamic concepts of the optimal Fontan physiology and Fontan circulatory failure, review practical aspects of invasive hemodynamic assessment, and discuss the role of drug therapies in increasing systemic venous blood flow return and decreasing ventricular filling pressures in Fontan circulation. Often complementary to catheter-based or surgical interventions, pharmacologic management aims at preserving patency of the circuit, adequate systolic and diastolic ventricular function, atrioventricular valve function, an unobstructed ventricular outflow tract, and pulmonary vascular integrity in order to maintain an acceptable cardiac output.

Sudden cardiac death in congenital heart disease.

Sudden cardiac death (SCD) accounts for up to 25% of deaths in patients with congenital heart disease (CHD). To date, research has largely been driven by observational studies and real-world experience. Drawbacks include varying definitions, incomplete taxonomy that considers SCD as a unitary diagnosis as opposed to a terminal event with diverse causes, inconsistent outcome ascertainment, and limited data granularity. Notwithstanding these constraints, identified higher-risk substrates include tetralogy of Fallot, transposition of the great arteries, cyanotic heart disease, Ebstein anomaly, and Fontan circulation. Without autopsies, it is often impossible to distinguish SCD from non-cardiac sudden deaths. Asystole and pulseless electrical activity account for a high proportion of SCDs, particularly in patients with heart failure. High-quality cardiopulmonary resuscitation is essential to improve outcomes. Pulmonary hypertension and CHD complexity are associated with lower likelihood of successful resuscitation. Risk stratification for primary prevention implantable cardioverter-defibrillators (ICDs) should consider the probability of SCD due to a shockable rhythm, competing causes of mortality, complications of ICD therapy, and associated costs. Risk scores to better estimate probabilities of SCD and CHD-specific guidelines and consensus-based recommendations have been proposed. The subcutaneous ICD has emerged as an attractive alternative to transvenous systems in those with vascular access limitations, prior device infections, intra-cardiac shunts, or a Fontan circulation. Further improving SCD-related outcomes will require a multidimensional approach to research that addresses disease processes and triggers, taxonomy to better reflect underlying pathophysiology, high-risk features, early warning signs, access to high-quality cardiopulmonary resuscitation and specialized care, and preventive therapies tailored to underlying mechanisms.

Palpitations Revealing a Primary Pulmonary Artery Sarcoma.

Primary pulmonary artery sarcoma is an exceedingly rare and aggressive malignancy that carries poor prognosis. Clinical manifestations are nonspecific and include chest pain, dyspnea, syncope, palpitations, and asthenia, among others. Delay to diagnosis is common and compromises the prognosis. Here, we report an interesting case of primary pulmonary artery sarcoma presenting with frequent monomorphic premature ventricular contractions arising from the right/left ventricle outflow tract. Cardiac imaging is key in the evaluation of patients with frequent premature ventricular contractions to rule out rare pathologies such as tumour compression.

Le sarcome primaire de l'artère pulmonaire est une tumeur maligne extrêmement rare et agressive de mauvais pronostic. Les manifestations cliniques sont non spécifiques et peuvent inclure de la douleur thoracique, de la dyspnée, des syncopes, des palpitations et de l'asthénie. Le retard diagnostic est fréquent et compromet le pronostic. Nous rapportons ici un cas intéressant de sarcome primaire de l'artère pulmonaire pour lequel le patient présentait des extrasystoles ventriculaires prématurées monomorphes qui provenaient des chambres de chasse des ventricules gauche et droit. L'imagerie est essentielle à l'évaluation des patients présentant de fréquentes extrasystoles ventriculaires afin d'écarter des pathologies rares comme la compression tumorale d'une chambre cardiaque.

Life-threatening arrhythmias with autosomal recessive TECRL variants.

AIMS: Sudden death and aborted sudden death have been observed in patients with biallelic variants in TECRL. However, phenotypes have only begun to be described and no data are available on medical therapy after long-term follow-up. METHODS AND RESULTS: An international, multi-centre retrospective review was conducted. We report new cases associated with TECRL variants and long-term follow-up from previously published cases. We present 10 cases and 37 asymptomatic heterozygous carriers. Median age at onset of cardiac symptoms was 8 years (range 1-22 years) and cases were followed for an average of 10.3 years (standard deviation 8.3), right censored by death in three cases. All patients on metoprolol, bisoprolol, or atenolol were transitioned to nadolol or propranolol due to failure of therapy. Phenotypes typical of both long QT syndrome and catecholaminergic polymorphic ventricular tachycardia (CPVT) were observed. We also observed divergent phenotypes in some cases despite identical homozygous variants. None of 37 heterozygous family members had a cardiac phenotype. CONCLUSION: Patients with biallelic pathogenic TECRL variants present with variable cardiac arrhythmia phenotypes, including those typical of long QT syndrome and CPVT. Nadolol and propranolol may be superior beta-blockers in this setting. No cardiac disease or sudden death was present in patients with a heterozygous genotype.

Arrhythmias in adults with congenital heart disease and heart failure.

Arrhythmias and heart failure are among the most common complications encountered by adults with congenital heart disease (CHD). In this contemporary review, we explore the interactions between arrhythmias and heart failure and discuss management strategies. Major knowledge gaps are highlighted throughout. Interactions between arrhythmias and heart failure are complex and bidirectional, with one begetting the other. Arrhythmias can provoke heart failure through various mechanisms: conduction disturbances may contribute to inefficient ventricular filling and contraction patterns; bradyarrhythmias and tachyarrhythmias can result in a reduction in cardiac output; hypoxemia may be exacerbated by right-to-left shunting; and tachycardia-induced cardiomyopathy has potentially devastating consequences if the diagnosis is delayed. In turn, heart failure promotes arrhythmogenesis through various structural (eg, fibrosis, chamber dilation, hypertrophy) and electrical remodeling effects that include changes to ion currents and channels and connexin expression, along with shortening of atrial and ventricular refractory periods with increased heterogeneity. Several shared comorbidities can contribute to, and modulate the impact of, arrhythmias and heart failure. Preemptive arrhythmia management can potentially mitigate effects on heart failure exacerbations. Similarly, optimal heart failure control could curtail its impact on arrhythmogenesis. Treatment strategies to prevent or treat heart failure in adults with CHD encompass pharmacological agents, catheter ablation, and device therapies including defibrillators, cardiac resynchronization therapy, and His bundle pacing. High-priority research avenues with major knowledge gaps include tachycardia-induced cardiomyopathy, catheter ablation of atrial fibrillation, defibrillator indications in high-risk subsets, and the role of cardiac resynchronization therapy and His bundle pacing in diverse forms of CHD.

Machine Learning Identifies Clinical and Genetic Factors Associated With Anthracycline Cardiotoxicity in Pediatric Cancer Survivors.

BACKGROUND: Despite known clinical risk factors, predicting anthracycline cardiotoxicity remains challenging. OBJECTIVES: This study sought to develop a clinical and genetic risk prediction model for anthracycline cardiotoxicity in childhood cancer survivors. METHODS: We performed exome sequencing in 289 childhood cancer survivors at least 3 years from anthracycline exposure. In a nested case-control design, 183 case patients with reduced left ventricular ejection fraction despite low-dose doxorubicin (≤250 mg/m2), and 106 control patients with preserved left ventricular ejection fraction despite doxorubicin >250 mg/m2 were selected as extreme phenotypes. Rare/low-frequency variants were collapsed to identify genes differentially enriched for variants between case patients and control patients. The expression levels of 5 top-ranked genes were evaluated in human induced pluripotent stem cell-derived cardiomyocytes, and variant enrichment was confirmed in a replication cohort. Using random forest, a risk prediction model that included genetic and clinical predictors was developed. RESULTS: Thirty-one genes were differentially enriched for variants between case patients and control patients (p < 0.001). Only 42.6% case patients harbored a variant in these genes compared to 89.6% control patients (odds ratio: 0.09; 95% confidence interval: 0.04 to 0.17; p = 3.98 × 10-15). A risk prediction model for cardiotoxicity that included clinical and genetic factors had a higher prediction accuracy and lower misclassification rate compared to the clinical-only model. In vitro inhibition of gene-associated pathways (PI3KR2, ZNF827) provided protection from cardiotoxicity in cardiomyocytes. CONCLUSIONS: Our study identified variants in cardiac injury pathway genes that protect against cardiotoxicity and informed the development of a prediction model for delayed anthracycline cardiotoxicity, and it also provided new targets in autophagy genes for the development of cardio-protective drugs. (Preventing Cardiac Sequelae in Pediatric Cancer Survivors [PCS2]; NCT01805778).

Eisenmenger Syndrome: A Multisystem Disorder-Do Not Destabilize the Balanced but Fragile Physiology.

Eisenmenger syndrome is the most severe and extreme phenotype of pulmonary arterial hypertension associated with congenital heart disease. A large nonrestrictive systemic left-to-right shunt triggers the development of pulmonary vascular disease, progressive pulmonary arterial hypertension, and increasing pulmonary vascular resistance at the systemic level, which ultimately results in shunt reversal. Herein, we review the changing epidemiological patterns and pathophysiology of Eisenmenger syndrome. Multiorgan disease is an integral manifestation of Eisenmenger syndrome and includes involvement of the cardiac, hematological, neurological, respiratory, gastrointestinal, urinary, immunological, musculoskeletal, and endocrinological systems. Standardized practical guidelines for the assessment, management, risk stratification, and follow-up of this very fragile and vulnerable population are discussed. Multidisciplinary care is the best clinical practice. An approach to the prevention and management of a broad spectrum of complications is provided. Relevant therapeutic questions are discussed, including anticoagulation, noncardiac surgery, physical activity, transplantation, and advanced-care planning (palliative care). Advanced pulmonary arterial hypertension therapies are indicated in patients with Eisenmenger syndrome and World Health Organization functional class II or higher symptoms to improve functional capacity, quality of life, and-less well documented-survival. Specific recommendations regarding monotherapy or combination therapy are provided according to functional class and clinical response. The ultimate challenge for all care providers remains early detection and management of intracardiac and extracardiac shunts, considering that Eisenmenger syndrome is a preventable condition.

Lead Extraction With Baffle Stenting in Adults With Transposition of the Great Arteries.

OBJECTIVES: This study sought to assess the feasibility, safety, and outcomes of a stepwise combined percutaneous approach that includes transvenous lead extraction (TLE) followed by baffle stenting and device reimplantation in patients with D-transposition of the great arteries (D-TGA) and atrial baffle dysfunction. BACKGROUND: Management of baffle leak or stenosis in patients with D-TGA and atrial switch surgery is challenging in the presence of transvenous cardiac implantable electronic devices. Baffle complications hinder device-related interventions and addressing baffle dysfunction often requires TLE. METHODS: All consecutive patients with D-TGA and TLE followed by a percutaneous baffle intervention at the Montreal Heart Institute between 2009 and 2018 were enrolled. RESULTS: Ten patients, median 38.6 years of age (range 15.2 to 50.6 years), 5 males (50.0%) were included. Procedures were performed for a device-related indication in 5 patients (50.0%) and for baffle dysfunction in 5 patients (50.0%). A total of 19 leads (17 pacing, 2 defibrillation) were targeted, with a median time from implantation of 8.7 (range 4.3 to 22.1) years. A laser sheath was most frequently required for successful TLE, which was achieved in all patients. Immediate baffle stenting was performed in 9 patients (90.0%) and immediate device reimplantation in 6 (60.0%). During a median follow-up of 3.0 (range 0.1 to 8.2) years, the only complication was subpulmonary atrioventricular valve damage requiring surgery in 1 patient, 8 months after the procedure. CONCLUSIONS: A combined approach with TLE followed by baffle stenting and reimplantation appears to be safe and feasible in D-TGA patients with atrial switch, baffle dysfunction, and transvenous leads.

Sudden death in transposition of the great arteries with atrial switch surgery: Autopsy evidence of acute myocardial ischemia despite normal coronary arteries.

BACKGROUND: Sudden death is the leading cause of mortality in patients with transposition of the great arteries (TGA) and atrial switch surgery. Understanding underlying mechanisms could contribute to identifying high-risk patients and preventing such catastrophic deaths. METHODS: A total of 144 adults (≥18 years) with TGA and atrial switch surgery were followed at our adult congenital center since 1989. Four patients were excluded: two with double-outlet right ventricles and two with subsequent arterial switch surgery in childhood. RESULTS: Of the remaining 140 patients, age 37.6 ±â€¯7.8 years, 37.1% female, 8 (6%) had a cardiac arrest of presumed arrhythmic etiology of whom 3 were resuscitated. The arrests occurred in 3 women and 5 men at age 30.5 ±â€¯8.6 (range 22 to 50) years. None had established coronary artery disease, sustained ventricular arrhythmias, or syncope. Four (50%) had atrial arrhythmias and 6 (75%) had at least moderate systemic right ventricular dysfunction. For 5 patients in whom circumstances surrounding the arrests were documented, 3 occurred on exertion, 1 after consuming recreational methamphetamine, and 1 in the context of an atrial tachyarrhythmia. Autopsies were performed in 2 of 5 patients. Both revealed acute massive myocardial infarction of the hypertrophied systemic right ventricle with normal coronary arteries and chronic subendocardial ischemic lesions. CONCLUSION: This is the first report to provide histopathological evidence in support of a myocardial ischemia hypothesis as a cause of sudden death in this patient population, despite the absence of coronary atherosclerosis.

Variability in the Echocardiographic Evaluation of the Systemic Right Ventricle.

BACKGROUND: Echocardiographic evaluation of the systemic right ventricle (sRV) remains challenging in patients with transposition of the great arteries (TGA) corrected by an atrial switch (AS) and with congenitally corrected TGA (ccTGA). The aim of this study was to determine the interobserver and intraobserver variability of echocardiographic parameters for sRV size and systolic function. METHODS: Six independent observers retrospectively interpreted 44 previously acquired echocardiograms (25 patients with TGA/AS and 19 patients with ccTGA). Quantitative parameters included inlet and longitudinal diameters, systolic and diastolic areas, fractional area change (FAC), and wall thickness. sRV dilatation and systolic function were qualitatively graded as normal, mild, moderate, or severe. sRV hypertrophy was graded as present or absent. Intraclass correlation coefficients (ICCs) and Kappa statistics were computed to assess interobserver variability. Images from 10 patients (5 TGA/AS and 5 ccTGA) were reinterpreted at a 1-month interval, and ICC and Kendall tau b statistics were computed to assess intraobserver variability. RESULTS: Interobserver and intraobserver agreement were good to excellent for sRV diameters, areas and FAC (ICC, 0.49-0.97), except for the sRV wall thickness (ICC < 0) and the FAC for 1 observer. Interobserver agreement was poor for the qualitative assessment of sRV size and systolic function (Kappa < 0.25), but with a good to excellent intraobserver agreement. CONCLUSIONS: These findings suggest that overall appreciation of sRV size and systolic function relies on variable interpretation of measurements by observers. Readers experienced in CHD and with clear thresholds for quantitative parameters, along with a validated algorithm, are required to guide the evaluation of sRV.

Transvenous Lead Extraction in Adults With Congenital Heart Disease: Insights From a 20-Year Single-Center Experience.

BACKGROUND: Safety and feasibility data on transvenous lead extraction (TLE) in the challenging population of adults with congenital heart disease (A-CHD) are limited. Herein, we report the results of TLE in A-CHD during a 20-year period. METHODS AND RESULTS: All consecutive TLE procedures in A-CHD were included in a monocentric prospective registry from 1996. A total of 121 leads were extracted in 49 A-CHD (median age, 38 years; 51% men) during 71 TLE procedures. Twenty-four (49%) patients had transposition of the great arteries. Main indications for extraction were infection in 34 (48%) and lead failure in 22 (31%). A laser sheath was required for 56 (46%) leads and a femoral approach for 10 (8%). Complete TLE was achieved for 111 leads (92%). In multivariable analysis, lead duration (odds ratio, 1.02; 95% confidence interval, 1.00-1.04; P<0.01) and number of previous cardiac surgeries (odds ratio, 2.65; 95% confidence interval, 1.52-4.67; P<0.01) were predictive of TLE failure. No perioperative death or pericardial effusion was observed. Subpulmonary atrioventricular valve regurgitation increased in 8 patients (5 with transposition of the great arteries) and was independently associated with an implantable cardioverter defibrillator lead (odds ratio, 9.69; 95% confidence interval, 1.31-71.64; P=0.03) and valvular vegetation (odds ratio, 7.29; 95% confidence interval, 1.32-40.51; P=0.02). After a median of 54 (19-134) months of follow-up after the first TLE, 3 deaths occurred independently from lead management. CONCLUSIONS: Despite complex anatomic issues, TLE can be achieved successfully in most A-CHD using advanced extraction techniques. Subpulmonary atrioventricular valve regurgitation is a prevalent complication, particularly in patients with transposition of the great arteries.

Late Onset Postcapillary Pulmonary Hypertension in Patients With Transposition of the Great Arteries and Mustard or Senning Baffles.

BACKGROUND: There is a paucity of data regarding late-onset pulmonary hypertension (PH) in patients with transposition of the great arteries and atrial switch surgery. METHODS AND RESULTS: A retrospective cohort study was conducted on 140 adults with transposition of the great arteries and atrial switch surgery, age 37.3±7.8, 37.1% female, in order to assess the prevalence and characteristics of late-onset PH and explore associated factors. Patients were followed for a median of 32.3 years after atrial switch surgery and 10.0 years after their first referral visit. PH was detected in 18 of 33 (54.5%) patients who had invasive hemodynamic studies. Average age at diagnosis of PH was 33.9±8.1 years. PH was postcapillary in all, with a mean pulmonary artery pressure of 36±12 mm Hg and mean pulmonary capillary wedge pressure of 28±8 mm Hg. PH was diagnosed in 13 of 17 (76.5%) patients who had cardiac catheterization for heart failure or decreased exercise tolerance. In multivariable analyses, systemic hypertension (odds ratio 9.4, 95% confidence interval 2.2-39.4, P=0.002) and heart failure or New York Heart Association class III or IV symptoms (odds ratio 49.8, 95% confidence interval 8.6-289.0, P<0.001) were independently associated with PH. Patients with PH were more likely to develop cardiovascular comorbidities including atrial (P=0.001) and ventricular (P=0.008) arrhythmias, require hospitalizations for heart failure (P<0.001), and undergo tricuspid valve surgery (P<0.001). Mortality was significantly higher in patients with PH (hazard ratio 9.4, 95% confidence interval 2.1-43.0], P<0.001). CONCLUSIONS: Late-onset postcapillary PH is highly prevalent in adults with transposition of the great arteries and atrial switch surgery and is associated with an adverse prognosis.

Characterization of a Human Induced Pluripotent Stem Cell-Derived Cardiomyocyte Model for the Study of Variant Pathogenicity: Validation of a KCNJ2 Mutation.

BACKGROUND: Long-QT syndrome is a potentially fatal condition for which 30% of patients are without a genetically confirmed diagnosis. Rapid identification of causal mutations is thus a priority to avoid at-risk situations that can lead to fatal cardiac events. Massively parallel sequencing technologies are useful for the identification of sequence variants; however, electrophysiological testing of newly identified variants is crucial to demonstrate causality. Long-QT syndrome could, therefore, benefit from having a standardized platform for functional characterization of candidate variants in the physiological context of human cardiomyocytes. METHODS AND RESULTS: Using a variant in Kir2.1 (Gly52Val) revealed by whole-exome sequencing in a patient presenting with symptoms of long-QT syndrome as a proof of principle, we demonstrated that commercially available human induced pluripotent stem cell-derived cardiomyocytes are a powerful model for screening variants involved in genetic cardiac diseases. Immunohistochemistry experiments and whole-cell current recordings in human embryonic kidney cells expressing the wild-type or the mutant Kir2.1 demonstrated that Kir2.1-52V alters channel cellular trafficking and fails to form a functional channel. Using human induced pluripotent stem cell-derived cardiomyocytes, we not only confirmed these results but also further demonstrated that Kir2.1-52V is associated with a dramatic prolongation of action potential duration with evidence of arrhythmic activity, parameters which could not have been studied using human embryonic kidney cells. CONCLUSIONS: Our study confirms the pathogenicity of Kir2.1-52V in 1 patient with long-QT syndrome and also supports the use of isogenic human induced pluripotent stem cell-derived cardiomyocytes as a physiologically relevant model for the screening of variants of unknown function.