Advance care planning and palliative care in ACHD: the healthcare providers' perspective.

BACKGROUND: Advance care planning and palliative care are gaining recognition as critical care components for adults with CHD, yet these often do not occur. Study objectives were to evaluate ACHD providers' 1) comfort managing patients' physical symptoms and psychosocial needs and 2) perspectives on the decision/timing of advance care planning initiation and palliative care referral. METHODS: Cross-sectional study of ACHD providers. Six hypothetical patients were described in case format, followed by questions regarding provider comfort managing symptoms, initiating advance care planning, and palliative care referral. RESULTS: Fifty providers (72% physicians) completed surveys. Participants reported low levels of personal palliative care knowledge, without variation by gender, years in practice, or prior palliative care training. Providers appeared more comfortable managing physical symptoms and discussing prognosis than addressing psychosocial needs. Providers recognised advance directives as important, although the percentage who would initiate advance care planning ranged from 18 to 67% and referral to palliative care from 14 to 32%. Barriers and facilitators to discussing advance care planning with patients were identified. Over 20% indicated that advance care planning and end-of-life discussions are best initiated with the development of at least one life-threatening complication/hospitalisation. CONCLUSIONS: Providers noted high value in advance directives yet were themselves less likely to initiate advance care planning or refer to palliative care. This raises the critical questions of when, how, and by whom discussion of these important matters should be initiated and how best to support ACHD providers in these endeavours.

Heart University: a new online educational forum in paediatric and adult congenital cardiac care. The future of virtual learning in a post-pandemic world?

Online learning has become an increasingly expected and popular component for education of the modern-day adult learner, including the medical provider. In light of the recent coronavirus pandemic, there has never been more urgency to establish opportunities for supplemental online learning. Heart University aims to be "the go-to online resource" for e-learning in CHD and paediatric-acquired heart disease. It is a carefully curated open access library of paedagogical material for all providers of care to children and adults with CHD or children with acquired heart disease, whether a trainee or a practising provider. In this manuscript, we review the aims, development, current offerings and standing, and future goals of Heart University.

Learning strategies among adult CHD fellows.

OBJECTIVE: Subspecialisation is increasingly a fundamental part of the contemporary practice of medicine. However, little is known about how medical trainees learn in the modern era, and particularly in growing and relatively new subspecialties, such as adult CHD. The purpose of this study was to assess institutional-led and self-directed learning strategies of adult CHD fellows. METHODS: This international, cross-sectional online survey was conducted by the International Society for Adult Congenital Heart Disease and consisted primarily of categorical questions and Likert rating scales. All current or recent (i.e., those within 2 years of training) fellows who reported training in adult CHD (within adult/paediatric cardiology training or within subspecialty fellowships) were eligible. RESULTS: A total of 75 fellows participated in the survey: mean age: 34 ± 5; 35 (47%) female. Most adult CHD subspecialty fellows considered case-based teaching (58%) as "very helpful", while topic-based teaching was considered "helpful" (67%); p = 0.003 (favouring case-based). When facing a non-urgent clinical dilemma, fellows reported that they were more likely to search for information online (58%) than consult a faculty member (29%) or textbook (3%). Many (69%) fellows use their smartphones at least once daily to search for information during regular clinical work. CONCLUSIONS: Fellows receiving adult CHD training reported a preference for case-based learning and frequent use of online material and smartphones. These findings may be incorporated into the design and enhancement of fellowships and development of online training resources.

Cardiac resynchronization therapy in adults with congenital heart disease.

Aims: In adults with congenital heart disease (CHD) heart failure is one of the leading causes of morbidity and mortality but experience with and reported outcome of cardiac resynchronization therapy (CRT) is limited. We investigated the efficacy of CRT in adults with CHD. Methods and results: This was a retrospective study including 48 adults with CHD who received CRT since 2003 in four tertiary referral centres. Responders were defined as patients who showed improvement in NYHA functional class and/or systemic ventricular ejection fraction by at least one category. Ventricular function was assessed by echocardiography and graded on a four point ordinal scale. Median age at CRT was 47 years (range 18-74 years) and 77% was male. Cardiac diagnosis included tetralogy of Fallot in 29%, (congenitally corrected) transposition of great arteries in 23%, septal defects in 25%, left sided lesions in 21%, and Marfan syndrome in 2% of the patients. The median follow-up duration after CRT was 2.6 years (range 0.1-8.8). Overall, 37 out of 48 patients (77%) responded to CRT either by improvement of NYHA functional class and/or systemic ventricular function. There were 11 non-responders to CRT. Of these, three patients died and four underwent heart transplantation. Conclusion: In this cohort of older CHD patients, CRT was accomplished with a success rate comparable to those with acquired heart disease despite the complex anatomy and technical challenges frequently encountered in this population. Further studies are needed to establish appropriate guidelines for patient selection and long term outcome.

Sudden cardiac death in adult congenital heart disease: can the unpredictable be foreseen?

AIMS: Sudden cardiac death (SCD) is a major cause of mortality in adults with congenital heart disease (CHD). Several risk factors for SCD including conduction disturbances and ventricular dysfunction have been described previously. However, electrocardiogram (ECG) and echocardiographic parameters may change over time, and the predictive value of such temporal changes, rather than their point estimates, for SCD remains unknown. METHODS AND RESULTS: This was a retrospective case-control study in adults with CHD and proven or presumed SCD and matched controls. Data were obtained from three databases including 25 000 adults with CHD. Sequential measurements were performed on electrocardiograms and echocardiograms. Ventricular function was assessed by echocardiography and graded on a four-point ordinal scale: 1, normal [ejection fraction (EF) ≥50%]; 2, mildly impaired (EF 40-49%); 3, moderately impaired (EF 30-39%); and 4, severely impaired (EF < 30%). Overall, 131 SCDs (mean age 36 ± 14 years, 67% male) and 260 controls (mean age 37 ± 13 years, 63% male) were included. At baseline, median QRS duration was 108 ms (range 58-168 ms) in SCDs and 97 ms (range 50-168 ms) in controls and increased over time at a rate of 1.6 ± 0.5 vs. 0.5 ± 0.2 ms/year in SCDs and controls, respectively (P = 0.011). QT dispersion at baseline was 61 ms (range 31-168 ms) in SCDs and 50 ms (range 21-129 ms) in controls. QT dispersion increased at a rate of 1.1 ± 0.4 ms/year in SCD victims and decreased at a rate of 0.2 ± 0.2 ms/year in controls (P = 0.004). Increase of QRS duration ≥5 ms/year was associated with an increased risk of SCD [OR 1.9, 95% confidence interval (CI) 1.1-3.3, P = 0.013]. Change from any baseline systemic ventricular function (normal, mild, or moderately impaired) to severe ventricular dysfunction over time was associated with the highest risk of SCD (OR 16.9, 95% CI 1.8-120.1, P = 0.008). CONCLUSION: In adults with CHD, QRS duration and ventricular dysfunction progress over time. Progression of QRS duration and the rate of impairment of ventricular function served to identify those at increased risk of SCD.

Revision: review of non-elective hospitalisations of adults with CHD.

Introduction The adult CHD population is increasing and ageing and remains at high risk for morbidity and mortality. In a retrospective single-centre study, we conducted a comprehensive review of non-elective hospitalisations of adults with CHD and explored factors associated with length of stay. METHODS: We identified adults (⩾18 years) with CHD admitted during a 12-month period and managed by the adult CHD service. Data regarding demographics, cardiac history, hospital admission, resource utilisation, and length of stay were extracted. RESULTS: There were 103 admissions of 91 patients (age 37±10 years; 52% female). Of 91 patients, 96% had moderate or complex defects. Of 103 admissions, 45% were through the emergency department. The most common reasons for admission were arrhythmia (37%) and heart failure (28%); 29% of admissions included a stay in the ICU. The mean number of consultations by other services was 2.0. Electrophysiology and anaesthesiology departments were most frequently consulted. After removing outliers, the mean length of stay was 7.9±7.4 days (median=5 days). The length of stay was longer for patients admitted for heart failure (12.2±10.3 days; p=0.001) and admitted directly to the ward (9.6±8.9 days; p=0.009). CONCLUSIONS: Among non-electively hospitalised adults with CHD in a tertiary-care centre, management often entails an interdisciplinary approach, and the length of stay is longest for patients admitted with heart failure. The healthcare system must ensure optimal resources to maintain high-quality care for this expanding patient population.

Surgical outcome of discrete subaortic stenosis in adults: a multicenter study.

BACKGROUND: Discrete subaortic stenosis is notable for its unpredictable hemodynamic progression in childhood and high reoperation rate; however, data about adulthood are scarce. METHODS AND RESULTS: Adult patients who previously underwent surgery for discrete subaortic stenosis were included in this retrospective multicenter cohort study. Mixed-effects and joint models were used to assess the postoperative progression of discrete subaortic stenosis and aortic regurgitation, as well as reoperation. A total of 313 patients at 4 centers were included (age at baseline, 20.2 years [25th-75th percentile, 18.4-31.0 years]; 52% male). Median follow-up duration was 12.9 years (25th-75th percentile, 6.2-20.1 years), yielding 5617 patient-years. The peak instantaneous left ventricular outflow tract gradient decreased from 75.7±28.0 mm Hg preoperatively to 15.1±14.1 mm Hg postoperatively (P<0.001) and thereafter increased over time at a rate of 1.31±0.16 mm Hg/y (P=0.001). Mild aortic regurgitation was present in 68% but generally did not progress over time (P=0.76). A preoperative left ventricular outflow tract gradient ≥80 mm Hg was a predictor for progression to moderate aortic regurgitation postoperatively. Eighty patients required at least 1 reoperation (1.8% per patient-year). Predictors for reoperation included female sex (hazard ratio, 1.53; 95% confidence interval, 1.02-2.30) and left ventricular outflow tract gradient progression (hazard ratio, 1.45; 95% confidence interval, 1.31-1.62). Additional myectomy did not reduce the risk for reoperation (P=0.92) but significantly increased the risk of a complete heart block requiring pacemaker implantation (8.1% versus 1.7%; P=0.005). CONCLUSIONS: Survival is excellent after surgery for discrete subaortic stenosis; however, reoperation for recurrent discrete subaortic stenosis is not uncommon. Over time, the left ventricular outflow tract gradient slowly increases and mild aortic regurgitation is common, although generally nonprogressive over time. Myectomy does not show additional advantages, and because it is associated with an increased risk of complete heart block, it should not be performed routinely.

Evaluation of a comprehensive cardiovascular magnetic resonance protocol in young adults late after the arterial switch operation for d-transposition of the great arteries.

BACKGROUND: In adults with prior arterial switch operation (ASO) for d-transposition of the great arteries, the need for routine coronary artery assessment and evaluation for silent myocardial ischemia is not well defined. In this observational study we aimed to determine the value of a comprehensive cardiovascular magnetic resonance (CMR) protocol for the detection of coronary problems in adults with prior ASO for d-transposition of the great arteries. METHODS: Adult ASO patients (≥18 years of age) were recruited consecutively. Patients underwent a comprehensive stress perfusion CMR protocol that included measurement of biventricular systolic function, myocardial scar burden, coronary ostial assessment and myocardial perfusion during vasodilator stress by perfusion CMR. Single photon emission computed tomography (SPECT) was performed on the same day as a confirmatory second imaging modality. Stress studies were visually assessed for perfusion defects (qualitative analysis). Additionally, myocardial blood flow was quantitatively analysed from mid-ventricular perfusion CMR images. In unclear cases, CT coronary angiography or conventional angiography was done. RESULTS: Twenty-seven adult ASO patients (mean age 23 years, 85% male, 67% with a usual coronary pattern; none with a prior coronary artery complication) were included in the study. CMR stress perfusion was normal in all 27 patients with no evidence of inducible perfusion defects. In 24 cases the coronary ostia could conclusively be demonstrated to be normal. There was disagreement between CMR and SPECT for visually-assessed perfusion defects in 54% of patients with most disagreement due to false positive SPECT. CONCLUSIONS: Adult ASO survivors in this study had no CMR evidence of myocardial ischemia, scar or coronary ostial abnormality. Compared to SPECT, CMR provides additional valuable information about the coronary artery anatomy. The data shows that the asymptomatic and clinically stable adult ASO patient has a low pre-test probability for inducible ischemia. In this situation it is likely that routine evaluation with stress CMR is unnecessary.

Natural history of discrete subaortic stenosisin adults: a multicentre study.

AIMS: Discrete subaortic stenosis (DSS) is often diagnosed early in life and known for its sometimes rapid haemodynamic progression in childhood and strong association with aortic regurgitation (AR). However, data about the evolution of DSS in adulthood are scarce. Therefore, we aimed to evaluate the natural history of DSS, and identify risk factors for the progression of DSS, AR, and intervention-free survival. METHODS AND RESULTS: Conservatively managed adult DSS patients were included in this retrospective multicentre cohort study. Mixed-effects and joint models were used to assess the progression of DSS and AR, and intervention-free survival. Longitudinal natural history data were available for 149 patients [age 20 (IQR: 18-34) years, 48% male]. Sixty patients (40.3%) had associated congenital heart defects (CHDs). The median follow-up duration was 6.3 (IQR: 3.0-12.4) years. The baseline peak left ventricular outflow tract (LVOT) gradient was 32.3 ± 17.0 mmHg and increased by 0.8 ± 0.1 mmHg/year. While the baseline LVOT gradient (P = 0.891) or age (P = 0.421) did not influence the progression rate, the presence of associated CHD was associated with faster progression (P = 0.005). Mild AR was common (58%), but did not significantly progress over time (P = 0.701). The median intervention-free survival was 16 years and associated with the baseline LVOT gradient [hazard ratio (HR) = 3.9 (95% CI: 2.0-7.6)], DSS progression [HR = 2.6 (95% CI: 2.0-3.5)], and AR [HR = 6.4 (95% CI 2.6-15.6)]. CONCLUSION: In contrast to children, DSS progresses slowly in adulthood. In particular, patients with associated CHD are at risk for faster progression and should be monitored cautiously. Discrete subaortic stenosis progression is not influenced by the baseline LVOT gradient or age. Mild AR is common, but non-progressive over time.

The value of stress perfusion cardiovascular magnetic resonance imaging for patients referred from the adult congenital heart disease clinic: 5-year experience at the Toronto General Hospital.

BACKGROUND: Vasodilator stress perfusion cardiovascular magnetic resonance imaging is a clinically useful tool for detection of clinically significant myocardial ischaemia in adults. We report our 5-year retrospective experience with perfusion cardiovascular magnetic resonance in a large, quarternary adult congenital heart disease centre. METHODS: We reviewed all cases of perfusion cardiovascular magnetic resonance in patients referred from the adult congenital heart disease service. Dipyridamole stress perfusion cardiovascular magnetic resonance was undertaken on commercially available 1.5 and 3 T cardiovascular magnetic resonance scanners. Late gadolinium enhancement imaging was performed 8-10 minutes after completion of the rest perfusion sequence. Navigator whole-heart coronary magnetic resonance angiography was also performed where feasible. RESULTS of stress cardiovascular magnetic resonance were correlated with complementary imaging studies, surgery, and clinical outcomes. RESULTS: Over 5 years, we performed 34 stress perfusion cardiovascular magnetic resonance examinations (11 positive). In all, 84% of patients had further investigations for ischaemia in addition to cardiovascular magnetic resonance. Within a subgroup of 19 patients who had definitive alternative assessment of their coronary arteries, stress perfusion cardiovascular magnetic resonance demonstrated a sensitivity of 82% and specificity of 100%. Of the 34 studies, two were false negatives, in which the aetiology of ischaemia was extrinsic arterial compression rather than intrinsic coronary luminal narrowing. Coronary abnormalities were identified in 71% of cases who had coronary magnetic resonance angiography. CONCLUSION: Stress perfusion cardiovascular magnetic resonance is a useful and accurate tool for investigation of myocardial ischaemia in an adult congenital heart disease population with suspected non-atherosclerotic coronary abnormalities.

Sudden cardiac death in adult congenital heart disease.

BACKGROUND: Sudden cardiac death (SCD) is a major cause of mortality in adults with congenital heart disease (CHD). The aim of this study was to determine the adult CHD population at risk of SCD and the clinical parameters associated with SCD. METHODS AND RESULTS: We performed a multicenter case-control study. Patients who died suddenly as a result of proven or presumed arrhythmia were included (cases). For each case, 2 controls matched on diagnosis, type of surgical intervention, age, and gender were included. From 3 databases including 25 790 adults with CHD, 1189 deaths (5%) were identified, of whom 213 patients (19%) died suddenly. Arrhythmic death occurred in 171 of 1189 patients. The underlying cardiac lesions were mild, moderate, and severe CHD in 12%, 33%, and 55% of the SCD cases, respectively. Clinical variables associated with SCD were supraventricular tachycardia (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.5-7.9; P=0.004), moderate to severe systemic ventricular dysfunction (OR, 3.4; 95% CI, 1.1-10.4; P=0.034), moderate to severe subpulmonary ventricular dysfunction (OR, 3.4; 95% CI, 1.1-10.2; P=0.030), increased QRS duration (OR, 1.34 [per 10-ms increase]; 95% CI, 1.10-1.34; P=0.008), and QT dispersion (OR, 1.22 [per 10-ms increase]; 95% CI, 1.22-1.48; P=0.008). CONCLUSIONS: The clinical parameters found to be associated with SCD in adults with a broad spectrum of CHD, including systemic right ventricles, are similar to those in ischemic heart disease. Moreover, even those patients with mild cardiac lesions are potentially at risk for SCD. This highlights the need for further prospective studies as well as vigilant ongoing follow-up of the adult with CHD.

Cardiac outcomes in adults with supravalvar aortic stenosis.

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

Patterns of cardiac and extracardiac anomalies in adults with tetralogy of fallot.

BACKGROUND: tetralogy of Fallot (TOF) is a complex congenital heart disease with clinical and genetic heterogeneity. Of the few known causes, 22q11.2 deletion syndrome (22q11DS) is the most common. We sought to define other clinical subgroups by focusing on cardiac and extracardiac features. METHODS: we prospectively screened a cohort of adults with TOF using an established protocol by which subjects were categorized as "syndromic" if they had at least 2 of 3 features: dysmorphic facies, learning difficulties, or voice abnormalities. We then compared the prevalence of cardiac and extracardiac features between subjects in the syndromic group (n = 56) and 112 age- and gender-matched subjects who did not meet our syndromic criteria. RESULTS: the syndromic group was more likely than the nonsyndromic group to have pulmonary atresia and/or major aortopulmonary collateral arteries (25% vs 13%, P = .04). There was a trend toward a higher prevalence of one or more major congenital extracardiac anomalies, primarily involving the musculoskeletal and genitourinary systems (25% vs 13%, P = .06). Later-onset conditions, including neuropsychiatric disorders (32% vs 17%, P = .03), thyroid disorders (20% vs 4%, P = .001), and hearing deficits (20% vs 0, P < .001), were more common in the syndromic group. The syndromic group tested (n = 50) had neither 22q11.2 deletions nor karyotypic anomalies. CONCLUSION: similar to 22q11DS, adults with TOF meeting screening criteria for a possible genetic syndrome are enriched for more severe cardiac disease and late-onset extracardiac features. Increased awareness of this subgroup with a multisystem condition may be helpful for identifying individuals for referral to medical genetics and optimizing management.

Healthcare needs of adults with congenital heart disease: study of the patient perspective.

BACKGROUND: More than 90% of infants born with congenital heart disease reach adulthood. International medical recommendations outline patient care needs in an effort to optimize patient health. There are, however, limited data focusing on the patient perspective. OBJECTIVES: This study investigated adult congenital heart disease patient-reported (1) barriers to medical care, (2) healthcare behaviors, and (3) concerns regarding medical, psychosocial, and lifestyle matters. METHODS: In this cross-sectional study, a questionnaire was distributed to all patients who attended a patient education conference. RESULTS: There were 123 adult congenital heart disease participants (58% female; mean age, 37 [SD, 13] years). The most common self-reported cardiac diagnoses were tetralogy of Fallot and transposition of the great arteries. Most patients did not report transportation or financial barriers to care, but did report the following: not wanting further surgery even if it was recommended (18%), not liking to think or talk about one's heart (17%), and not understanding doctors' information; 8% of patients inaccurately considered themselves to be "cured." With regard to healthcare behaviors, more than 80% of patients reported annual family physician and dentist visits, but 34% of patients were unaware when to seek urgent medical attention. Patients reported moderate to extreme concern about the following medical topics: heart rhythm problems (82%), infections (74%), and understanding treatment options (71%). Patients most often reported moderate to extreme concern about the following lifestyle and psychosocial topics: physical activity (77%), insurance (72%), assuming increased health responsibility (73%), diet (71%), mental health (60%), and death and dying (57%). CONCLUSIONS: This study provides important information about 3 specific areas. First, there are potential barriers to care beyond financial and transportation challenges. Second, many patients require education regarding when to seek urgent medical attention. Third, the concerns of this patient population are not limited to medical information. A patient-centered educational program is recommended.

Veno-venous bridges: the forerunners of the sinus venosus defect.

BACKGROUND: Differentiation of the so-called sinus venosus defect from other defects permitting shunting between the atrial chambers remains problematic. The lesion is not a true septal defect, and current theories to explain the existence of the sinus venosus defect fall short. The presence of persistent systemic to pulmonary venous connections has been proposed to explain the existence of the sinus venosus defect. METHODS: Clinical histories and radiological findings of six patients are reviewed. Three patients have veno-venous bridges, two have partial anomalous pulmonary venous connections, and one patient has a sinus venosus defect. The clinical information is reviewed, along with current developmental and morphological considerations. DISCUSSION: We provide radiographic, developmental, and morphological evidence to support the theory that a so-called sinus venosus defect is the consequence of persistence of foetal systemic to pulmonary veno-venous bridges, rather than of deficiencies in atrial septation.

Augmentation of pulmonary blood flow and cardiac output by non-invasive external ventilation late after Fontan palliation.

OBJECTIVES: Although a life-preserving surgery for children with single ventricle physiology, the Fontan palliation is associated with striking morbidity and mortality with advancing age. Our primary objective was to evaluate the impact of non-invasive, external, thoraco-abdominal ventilation on pulmonary blood flow (PBF) and cardiac output (CO) as measured by cardiovascular magnetic resonance (CMR) imaging in adult Fontan subjects. METHODS: Adults with a dominant left ventricle post-Fontan palliation (lateral tunnel or extracardiac connections) and healthy controls matched by sex and age were studied. We evaluated vascular flows using phase-contrast CMR imaging during unassisted breathing, negative pressure ventilation (NPV) and biphasic ventilation (BPV). Measurements were made within target vessels (aorta, pulmonary arteries, vena cavae and Fontan circuit) at baseline and during each ventilation mode. RESULTS: Ten Fontan subjects (50% male, 24.5 years (IQR 20.8-34.0)) and 10 matched controls were studied. Changes in PBF and CO, respectively, were greater following BPV as compared with NPV. In subjects during NPV, PBF increased by 8% (Δ0.20 L/min/m2 (0.10-0.53), p=0.011) while CO did not change significantly (Δ0.17 L/min/m2 (-0.11-0.23), p=0.432); during BPV, PBF increased by 25% (Δ0.61 L/min/m2 (0.20-0.84), p=0.002) and CO increased by 16% (Δ0.47 L/min/m2 (0.21-0.71), p=0.010). Following BPV, change in PBF and CO were both significantly higher in subjects versus controls (0.61 L/min/m2 (0.2-0.84) vs -0.27 L/min/m2 (-0.55-0.13), p=0.001; and 0.47 L/min/m2 (0.21-0.71) vs 0.07 L/min/m2 (-0.47-0.33), p=0.034, respectively). CONCLUSION: External ventilation acutely augments PBF and CO in adult Fontan subjects. Confirmation of these findings in larger populations with longer duration of ventilation and extended follow-up will be required to determine sustainability of haemodynamic effects.

Role of amiodarone in the management of atrial arrhythmias in adult Fontan patients.

BACKGROUND: Patients with Fontan circulation are known to be at high risk for developing atrial tachyarrhythmias (AAs). Our objective was to examine the efficacy and safety of amiodarone in the management of ATs in adult Fontan patients. METHODS: Primary outcomes of this single-centre, retrospective study included freedom from AAs and incidence of adverse effects of amiodarone on Fontan patients. Heart failure (HF) events and composite outcomes of death from any cause, Fontan revision and heart transplantation were evaluated as secondary outcomes. Predictors of HF and discontinuing amiodarone were also evaluated. RESULTS: A total of 61 patients (mean age 31.6±11.3 years, 40.9% female), who were treated with amiodarone in between 1995 and 2018, were included. AAs free survival at 1, 3 and 5 years were 76.2%, 56.9% and 30.6%, respectively. During a median follow-up of 50.5 months, 34 (55.7%) patients developed side effects, and 20 (32.8%) patients discontinued amiodarone due to side effects. Thyroid dysfunction was the most common side effect (n=26, 76.5%), amiodarone-induced thyrotoxicosis (AIT) (n=16, 27.1%) being most common thyroid dysfunction. Young age (age <28.5 years) was associated with discontinuing amiodarone (HR 5.50, 95% CI 1.19 to 25.4, p=0.029). AIT significantly increased risk of HF (HR 4.82, 95% CI 1.71 to 13.6, p=0.003). CONCLUSIONS: Short-term efficacy of amiodarone in Fontan physiology is acceptable. However, long-term administration is associated with a reduction of efficacy and a significant prevalence of non-cardiac side effects. AIT is associated with exacerbation of HF. The judicious use of amiodarone administration should be considered in this population.

Safety and Long-term Outcomes of Defibrillator Therapy in Patients With Right-Sided Implantable Cardiac Devices in Adults With Congenital Heart Disease.

BACKGROUND: Implantable cardioverter-defibrillators (ICDs) have been proven to prevent sudden cardiac death in adult congenital heart disease (ACHD) patients. Although the left side is chosen by default, implantation from the right side is often required. However, little is known about the efficacy and safety of right-sided ICDs in ACHD patients. METHODS: In this study we reviewed a total of 191 ACHD patients undergoing ICD/cardioverter resynchronisation therapy-defibrillator (CRT-D) implantation at our hospital between 2001 and 2019 (134 men and 57 women; age [mean ± standard deviation], 41.5 ± 14.8 years). RESULTS: Twenty-seven patients (14.1%) had right-sided devices. The most common causes of right-sided implantation were persistent left superior vena cava and vein occlusion (37.0%). Although procedure time (202.8 ± 60.5 minutes vs 143.8 ± 69.1 minutes, P = 0.008) was longer and the procedural success was lower (92.6% vs 99.4%, P = 0.008) for right-sided devices, no difference in R-wave and pacing threshold were noted. Among the 47 patients (24.6%) who underwent defibrillation threshold testing (DFT), no difference in DFT was observed (25.2 ± 5.3 J vs 23.8 ± 4.1 J, P = 0.460). During the median follow-up of 42.4 months, appropriate ICD therapy was observed in 5 (18.5%) and 30 (18.3%) patients for right- and left-sided ICDs/CRTDs, respectively (P = 0.978). No significant difference was seen in complications between them. CONCLUSIONS: Implantation of an ICD on the right side is technically challenging, but it is feasible as an alternative approach for ACHD patients with contraindications to left-sided device implantation.

Impact of Catheter Ablation for Atrial Arrhythmias on Repeat Cardioversion in Adults With Congenital Heart Disease.

BACKGROUND: Atrial tachyarrhythmias (AAs) are the main source of morbidity and mortality in adult congenital heart disease (ACHD). Direct-current cardioversion (DCCV) is an effective method to acutely terminate AAs, but many patients require repeated DCCV. Little is known about the impact of radiofrequency catheter ablation (RFCA) of AAs on the incidence of repeated DCCV in patients with ACHD. The purpose of this study was to evaluate the impact of RFCA on the incidence of DCCV in patients with ACHD. METHODS: A total of 157 patients with ACHD undergoing DCCV in our hospital from 2011 to 2018 (female n = 76 [48.4%], mean age 37.8 ± 12.5 y), were reviewed. The median follow-up period was 31.8 months (interquartile range 16.3-55.1 mo). RESULTS: Out of the total of 157 patients, 102 (65.0%) underwent RFCA for AAs, and 55 (35.0%) were treated without RFCA. Successful RFCA with termination of AAs during ablation was 62.7%. More than one-half of the patients had complex forms of CHD (62.4%). During follow-up, 57 patients (55.9%) who had RFCA developed recurrence of AAs, and 36 patients (35.2%) underwent repeated DCCV. Thirty-three (60.0%) out of 55 patients without RFCA required repeated cardioversion. Compared with patients without RFCA, RFCA significantly reduced the need for repeated DCCV by 40% (hazard ratio [HR] 0.60, 95% confidence interval [CI] 0.23-0.80; P = 0.009). In multivariate analysis, successful RFCA was associated with reduced risk of DCCV (HR 0.41, 95% CI 0.19-0.92; P = 0.031). CONCLUSIONS: AAs remain common despite RFCA in patients with ACHD. Nevertheless, RFCA is associated with a marked reduction in the need for repeated DCCV.

The Role of Ablation in Prevention of Recurrent Implantable Cardioverter Defibrillator Shocks in Patients With Tetralogy of Fallot.

BACKGROUND: Implantable cardioverter defibrillators (ICDs) are effective in preventing arrhythmic sudden cardiac death in patients with tetralogy of Fallot (TOF). Although ICD therapies for malignant ventricular arrhythmias can be life-saving, shocks could have deleterious consequences. Substrate-based ablation therapy has become the standard of care to prevent recurrent ICD shocks in patients with ischemic cardiomyopathy. However, the efficacy and safety of this invasive therapy in the prevention of recurrent ICD shocks in patients with TOF has not been well evaluated. METHODS: Records of a total of 47 consecutive TOF patients (mean age: 43.1 ± 13.2 years, male sex: n = 34 [72.3%]) who underwent ICD implantation for secondary prevention between 2000 and 2018 were reviewed. RESULTS: Twenty (42.6%) patients underwent invasive therapy (radiofrequency catheter ablation, n = 8; surgical ablation with pulmonary valve replacement, n = 12) before ICD implantation. Twenty-seven patients (57.4%) were managed noninvasively. During follow-up (median 80.5 [interquartile range, 28.5-131.0] months), 2 (10.0%) patients in the invasive group and 10 (37.0%) patients in the noninvasive group received appropriate ICD shocks (P = 0.036). Logistic regression analysis showed that invasive therapy was associated with a decreased risk of ICD shocks by 81.1% (odds ratio, 0.189; 95% confidence interval, 0.036-0.990; P = 0.049). Furthermore, invasive therapy was associated with decreased risk of the composite outcomes of ICD shock, death, cardiac transplantation, and hospital admission (odds ratio, 0.090; 95% confidence interval, 0.025-0.365; P = 0.013) compared with noninvasive therapy. CONCLUSIONS: Invasive substrate modification therapy was associated with a lower likelihood of ICD shocks and improvement of long-term outcomes in TOF patients.

CONTEXTE: Les défibrillateurs cardioverteurs implantables (DCI) sont efficaces pour prévenir la mort cardiaque subite provoquée par une arythmie chez les patients présentant une tétralogie de Fallot (TF). Bien que le traitement des arythmies ventriculaires malignes par DCI puisse sauver des vies, les chocs administrés peuvent avoir des conséquences délétères. L'ablation du substrat est devenue le traitement de référence pour prévenir l'administration à répétition de chocs par DCI chez les patients atteints d'une cardiomyopathie ischémique. L'efficacité et l'innocuité de ce traitement invasif pour prévenir l'administration de chocs répétés chez les patients présentant une TF n'ont toutefois pas été bien évaluées. MÉTHODOLOGIE: Nous avons examiné les cas consécutifs de 47 patients présentant une TF (âge moyen : 43,1 ± 13,2 ans; hommes : n = 34 [72,3 %]) ayant reçu un DCI en prévention secondaire entre 2000 et 2018. RÉSULTATS: Au total, 20 (42,6 %) patients ont subi un traitement invasif (ablation par cathéter par radiofréquence, n = 8; ablation chirurgicale et remplacement de la valve pulmonaire, n = 12) avant l'implantation d'un DCI. Vingt-sept patients (57,4 %) ont été pris en charge de façon non invasive. Au cours de la période de suivi (durée médiane de 80,5 [intervalle interquartile : 28,5 à 131,0] mois), 2 (10,0 %) patients du groupe ayant subi une intervention invasive et 10 (37,0 %) patients du groupe ayant subi une intervention non invasive ont reçu un choc approprié par DCI (p = 0,036). Les résultats de l'analyse par régression logistique montrent que le traitement invasif est associé à une réduction du risque de choc par DCI de 81,1 % (rapport des cotes : 0,189; intervalle de confiance à 95 % : de 0,036 à 0,990; p = 0,049). En outre, le traitement invasif est associé à une réduction du risque de survenue d'un des événements du paramètre d'évaluation composé, soit un choc administré par DCI, le décès, une transplantation cardiaque ou une hospitalisation (rapport des cotes : 0,090; intervalle de confiance à 95 % : de 0,025 à 0,365; p = 0,013) par rapport au traitement non invasif. CONCLUSIONS: La modification invasive du substrat a été associée à une probabilité plus faible de choc administré par DCI et à une amélioration des résultats à long terme chez les patients présentant une TF.