The 30-Year Outcomes of Tetralogy of Fallot According to Native Anatomy and Genetic Conditions.

BACKGROUND: The reported survival of tetralogy of Fallot (TOF) is > 97%. Patients with pulmonary atresia and/or genetic conditions have worse outcomes, but long-term estimates of survival and morbidity for these TOF subgroups are scarce. The objective of this study was to describe the 30-year outcomes of TOF according to native anatomy and the coexistence of genetic conditions. METHODS: The TRIVIA (Tetralogy of Fallot Research for Improvement of Valve Replacement Intervention: A Bridge Across the Knowledge Gap) study is a retrospective population-based cohort including all TOF subjects born from 1980 to 2015 in Québec. We evaluated all-cause mortality by means of Cox proportional hazards regression, and cumulative mean number of cardiovascular interventions and unplanned hospitalisations with the use of marginal means/rates models. We computed 30-year estimates of outcomes according to TOF types, ie, classic TOF (cTOF) and TOF with pulmonary atresia (TOF-PA), and the presence of genetic conditions. RESULTS: We included 960 subjects. The median follow-up was 17 years (interquartile range, 8-27). Nonsyndromic cTOF subjects had a 30-year survival of 95% and had undergone a mean of 2.8 interventions and 0.5 hospitalisations per subject. In comparison, TOF-PA subjects had a lower 30-year survival of 78% and underwent a mean of 8.1 interventions, with 4 times as many hospitalisations. The presence of a genetic condition was associated with lower survival (< 85% for cTOF and < 60% for TOF-PA) but similar numbers of interventions and hospitalisations. CONCLUSIONS: The anatomic types and the presence of genetic conditions strongly influence the long-term outcomes of TOF. We provided robust 30-year estimates for key markers of prognosis that may be used to improve risk stratification and provide more informed counselling to families.

Long-Term Follow-Up of Patients With Tetralogy of Fallot and Implantable Cardioverter Defibrillator: The DAI-T4F Nationwide Registry.

BACKGROUND: Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease, and sudden cardiac death represents an important mode of death in these patients. Data evaluating the implantable cardioverter defibrillator (ICD) in this patient population remain scarce. METHODS: A Nationwide French Registry including all patients with tetralogy of Fallot with an ICD was initiated in 2010 by the French Institute of Health and Medical Research. The primary time to event end point was the time from ICD implantation to first appropriate ICD therapy. Secondary outcomes included ICD-related complications, heart transplantation, and death. Clinical events were centrally adjudicated by a blinded committee. RESULTS: A total of 165 patients (mean age, 42.2±13.3 years, 70.1% males) were included from 40 centers, including 104 (63.0%) in secondary prevention. During a median (interquartile range) follow-up of 6.8 (2.5-11.4) years, 78 (47.3%) patients received at least 1 appropriate ICD therapy. The annual incidence of the primary outcome was 10.5% (7.1% and 12.5% in primary and secondary prevention, respectively; P=0.03). Overall, 71 (43.0%) patients presented with at least 1 ICD complication, including inappropriate shocks in 42 (25.5%) patients and lead dysfunction in 36 (21.8%) patients. Among 61 (37.0%) patients in primary prevention, the annual rate of appropriate ICD therapies was 4.1%, 5.3%, 9.5%, and 13.3% in patients with, respectively, 0, 1, 2, or ≥3 guidelines-recommended risk factors. QRS fragmentation was the only independent predictor of appropriate ICD therapies (hazard ratio, 3.47 [95% CI, 1.19-10.11]), and its integration in a model with current criteria increased the 5-year time-dependent area under the curve from 0.68 to 0.81 (P=0.006). Patients with congestive heart failure or reduced left ventricular ejection fraction had a higher risk of nonarrhythmic death or heart transplantation (hazard ratio, 11.01 [95% CI, 2.96-40.95]). CONCLUSIONS: Patients with tetralogy of Fallot and an ICD experience high rates of appropriate therapies, including those implanted in primary prevention. The considerable long-term burden of ICD-related complications, however, underlines the need for careful candidate selection. A combination of easy-to-use criteria including QRS fragmentation might improve risk stratification. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03837574.

Peritoneal dialysis in an adult patient with tetralogy of Fallot diagnosed with incomplete Alagille syndrome.

BACKGROUND: Alagille syndrome is an autosomal dominant disorder usually caused by pathogenic variants of the JAG1 gene. In the past, cholestasis was a condition sine qua non for diagnosis of the syndrome. However, recent advancements in genetic testing have revealed that clinical presentations vary from lack of symptoms, to multiorgan involvement. Tetralogy of Fallot, the most frequent complex congenital heart defect in Alagille Syndrome, very rarely leads to renal failure requiring dialysis - there are only single reports of such cases in the literature, with none of them in Alagille Syndrome. CASE PRESENTATION: A 41-year-old woman suffering from cyanosis, dyspnea and plethora was admitted to the hospital. The patient suffered from chronic kidney disease and tetralogy of Fallot and had been treated palliatively with Blalock-Taussig shunts in the past; at admission, only minimal flow through the left shunt was preserved. These symptoms, together with impaired mental status and dysmorphic facial features, led to extensive clinical and genetic testing including whole exome sequencing. A previously unknown missense variant c.587G > A within the JAG1 gene was identified. As there were no signs of cholestasis, and subclinical liver involvement was only suggested by elevated alkaline phosphatase levels, the patient was diagnosed with incomplete Alagille Syndrome. End-stage renal disease required introduction of renal replacement therapy. Continuous ambulatory peritoneal dialysis was chosen and the patient's quality of life significantly increased. However, after refusal of further treatment, the patient died at the age of 45. CONCLUSIONS: Tetralogy of Fallot should always urge clinicians to evaluate for Alagille Syndrome and offer patients early nephrological care. Although tetralogy of Fallot rarely leads to end-stage renal disease requiring dialysis, if treated palliatively and combined with renal dysplasia (typical of Alagille Syndrome), it can result in severe renal failure as in the presented case. There is no standard treatment for such cases, but based on our experience, peritoneal dialysis is worth consideration. Finally, clinical criteria for the diagnosis of Alagille Syndrome require revision. Previously, diagnosis was based on cholestasis - however, cardiovascular anomalies are found to be more prevalent. Furthermore, the criteria do not include renal impairment, which is also common.

Short to medium term outcomes of right ventricular outflow tract stenting as initial palliation for symptomatic infants with complete atrioventricular septal defect with associated tetralogy of Fallot.

OBJECTIVES: To assess the impact of right ventricular outflow tract (RVOT) stenting as the primary palliation in infants with complete atrioventricular septal defect with associated tetralogy of Fallot (cAVSD/TOF). BACKGROUND: Historically, palliation of symptomatic patients with cAVSD/TOF has been achieved through surgical systemic to pulmonary artery shunting. More recently RVOT stenting has evolved as an acceptable alternative in patients with tetralogy of Fallot. METHODS: Retrospective review of all patients with cAVSD/TOF who underwent RVOT stenting as palliation over a 13-year period from two large tertiary referral centers. RESULTS: Twenty-six patients underwent RVOT stenting at a median age of 57 days (interquartile range [IQR] 25.5-106.5). Median weight for stent deployment was 3.7 kg (IQR 2.91-5.5 kg). RVOT stenting improved oxygen saturations from a median of 72% (IQR 70-76%) to 90% (IQR 84-92%), p < .001. There was a significant increase in the median Z-score for both branch pulmonary arteries at median follow-up of 255 days (IQR 60-455). Eight patients required RVOT stent balloon dilatations and 8 patients required re-stenting for progressive desaturation. The median duration between reinterventions was 122 days (IQR 53-294 days). Four patients died during the follow-up period. No deaths resulted from the initial intervention. To date, definitive surgical intervention was achieved in 19 patients (biventricular repair n = 15) at a median age of 369 days (IQR 223-546 days). CONCLUSION: RVOT stenting in cAVSD/TOF is a safe and effective palliative procedure in symptomatic infants, promoting pulmonary artery growth and improving oxygen saturations.

Initiation of peritoneal dialysis in a patient with chronic renal failure associated with tetralogy of Fallot: a case report.

BACKGROUND: Tetralogy of Fallot is the most common cyanotic congenital heart disease. Patients with the condition have a high risk of developing chronic kidney disease. Treatment of kidney disease in patients with complex hemodynamics presents unique challenges. However, there are very few reports on the treatment of end-stage renal failure in patients with tetralogy of Fallot. CASE PRESENTATION: We present a rare case of peritoneal dialysis in a 47-year-old man with tetralogy of Fallot who had not undergone intracardiac repair. Peritoneal dialysis successfully removed fluids and solutes without adversely affecting the patient's hemodynamics. Our patient was managed with peritoneal dialysis for 5 years before he succumbed to sepsis secondary to digestive tract perforation. CONCLUSIONS: In this paper, we discuss the importance of monitoring acid-base balance, changes in cyanosis, and hyperviscosity syndrome during peritoneal dialysis in patients with tetralogy of Fallot. Lower leg edema and B-type natriuretic peptide level were useful monitoring parameters in this case. This case illustrates that with attention to the patient's unique requirements, peritoneal dialysis can provide successful renal replacement therapy without compromising hemodynamics in patients with tetralogy of Fallot.

First reported case of unrepaired tetralogy of Fallot complicated with coronavirus disease-19 (COVID-19).

The incidence of novel coronavirus disease-19 (nCoV-19) and its associated complications is higher in high-risk groups. In this article, we explain the symptoms and course of the disease and the treatment for an adult patient with CHD who has been infected with novel nCoV-19.

Defibrillators in adult congenital heart disease: Long-term risk of appropriate shocks, inappropriate shocks, and complications.

AIMS: Sudden cardiac death (SCD) accounts for up to 25% of deaths in the adult congenital heart disease (ACHD) population. Current guidelines for defibrillator implantation are either extrapolated from acquired cardiac disease or are based upon single lesion studies, predominantly Tetralogy of Fallot (TOF). Defibrillator-related morbidity appears to be substantially higher in ACHD patients. METHODS: We retrospectively evaluated all patients in our ACHD database who received an implantable cardioverter-defibrillator (ICD) between 2000 and 2019, and who were ≥16 years old at time of implant. Patients were followed for appropriate shocks, inappropriate shocks, and complications. RESULTS: Of 4748 patients in our database, 59 patients (1.2%) underwent ICD implantation. ICDs were for primary prevention in 63% and secondary prevention in 37%. Over a median follow-up of 6.6 years, 24% received an appropriate shock, 27% an inappropriate shock, and 42% suffered a device-related complication (annualized risks of 3.2%, 3.6%, and 5.7%, respectively). There were no significant predictors of appropriate shocks or inappropriate shocks. All appropriate shocks in primary prevention patients occurred in TOF or transposition of the great arteries (TGA) with atrial switch, typically in the presence of multiple SCD risk factors. The majority of inappropriate shocks were due to supraventricular arrhythmias. Device-related mortality was 1.7% (0.3% per annum). CONCLUSIONS: Appropriate shocks were relatively common in an ACHD ICD population followed in the long term. Device-related morbidity was significant. Although risk factors have been established for TOF, and to a lesser extent TGA, risk stratification for ICD implantation in ACHD remains challenging.

Management of Unoperated Tetralogy of Fallot in a 59-Year-Old Patient.

Tetralogy of Fallot is the most common cyanotic congenital heart defect consisting of an overriding aorta, right ventricular outflow obstruction, ventricular septal defect, and right ventricular hypertrophy. Without surgical management, approximately only 3% of patients survive past the age of 40 years. Cases of unoperated patients reaching adulthood have been reported; however, few studies describe treatment guidelines for surgical or therapeutic management. In this article, we report the case of a 59-year-old Hispanic male with unoperated tetralogy of Fallot presenting to our cardiology clinic for initial workup and management.

Third trimester predictors of interventional timing and accuracy of fetal anticipatory guidance in tetralogy of Fallot: A multi-center study.

OBJECTIVE: The objective was to evaluate and improve accuracy of anticipatory counseling regarding neonatal intervention for prenatally diagnosed tetralogy of Fallot (TOF) by assessing new and previously published predictors of neonatal intervention. METHODS: This is a multi-center, retrospective study from three centers of 112 fetal TOF patients undergoing third trimester fetal echocardiograms from 2004 to 2017. Additional cardiac defects requiring neonatal intervention were excluded. Fetal echocardiographic, clinical, and consultation data were compared between neonatal and late intervention. Optimal echocardiographic values were determined. RESULTS: Twenty-six infants (23%) required neonatal intervention. Those infants had significantly different pulmonary valve (PV) z-scores, PV:aortic valve (AoV) ratios, PV:AoV z-score differences (absolute difference between z-scores), and increased likelihood of abnormal ductal flow. Counseling during fetal echocardiogram regarding interventional timing was accurate for 50% needing neonatal intervention and 86% undergoing late intervention (P = .002). The best neonatal intervention predictors were PV:AoV ratio of <0.6 and counseling for neonatal intervention. PV:AoV z-score difference ≥5 provided 89% negative predictive value for excluding patients from neonatal repair. CONCLUSIONS: Third trimester fetal echocardiograms can predict interventional timing. The best predictors of neonatal intervention are PV:AoV ratio <0.6, PV:AoV z-score difference ≥5, and cardiologist counseling that neonatal intervention was likely.

Early palliative balloon pulmonary valvuloplasty in neonates and young infants with tetralogy of Fallot.

We aim to clarify the efficacy of early palliative balloon pulmonary valvuloplasty (BPV) in neonates and young infants (< 60 days) with tetralogy of Fallot (TOF). We performed palliative BPV in 31 subjects, regardless of the presence of cyanosis, with Z score of the pulmonary valve diameter (PVD) less than - 2.00. Primary and secondary endpoints were to avoid early surgical interventions for subjects within 6 months of age and to undergo the pulmonary valve-sparing procedure at corrective surgery, respectively. We studied factors associated with these outcomes among them. BPV was performed at 19 days (14-33) of age and with a weight of 3.34 kg (3.02-3.65). Systemic oxygen saturation, Z score of the PVD, and pulmonary arterial index (PAI) were 87% (81-91), - 3.56 (- 4.15 to - 2.62), and 128 mm2/m2 (102-157), respectively. There were 16 and 13 subjects who avoided early surgical interventions and transannular repair, respectively. At the primary endpoint, there was no significant difference in age, weight, systemic oxygen saturation, and Z score of the PVD and PAI between the groups. However, there was a significant difference in the infundibular morphology (severe: mild-to-moderate, 8:8 vs 13:2, P = 0.029) between the groups. We performed prophylactic BPV within 30 days after birth in 7 acyanotic TOF patients with severe infundibular obstruction, among whom 5 avoided early surgical intervention. At the secondary endpoint, there were no significant difference in weight, systemic oxygen saturation, but in sex, age at BPV, and Z score of the PVD. Early palliative BPV prevented early surgical intervention in half of the neonates and young infants with TOF, which depended upon the degree of infundibular obstruction. However, early palliative BPV did not contribute to avoid transanular patch right-ventricular outflow repair among them.

Cardiac Implantable Electronic Devices in Adults with Tetralogy of Fallot.

Patient with repaired tetralogy of Fallot (TOF) sometimes require cardiac implantable electronic devices (CIED) for tachy/bradyarrhythmias. There are no population-based studies of CIED-related outcomes in the adult TOF population. We reviewed the Nationwide/National Inpatient Sample to determine trends in CIED-related admissions in adults with TOF repair. This is a retrospective review of the Nationwide/National Inpatient Sample database from January 1, 2000 to December 31, 2014. There were 18,353 admissions in adults with TOF diagnosis, and of these, CIED were implanted in 792 (4.3%) admissions (CIED-related admissions). Of these 792 CIED-related admissions, pacemakers were implanted in 242 (30.7%) yielding an incidence of 1.3% and implantable cardioverter-defibrillators were implanted in 550 (69.4%) yielding an incidence of 3.0%. In-hospital mortality occurred in 14 (1.8%) of the CIED-related admissions. The mean hospital length of stay was 7.7 ± 1.3 days and inflation-adjusted hospitalization cost was $141,860 ± $127,516. In 5-year intervals (2000 to 2004, 2005 to 2009, and 2010 to 2014), there was a temporal increase in the incidence of CIED-related admissions (3.7% vs 4.4% vs 4.9%, p = 0.006). There was a similar trend in the age at the time of implantation (37.7 ± 14.2 vs 38.2 ± 13.1 vs 39.0 ± 14.5 years, p < 0.001) and Charlson Comorbidity Index (1.1 ± 1.4 vs 1.4 ± 1.8 vs 1.3 ± 1.7, p < 0.001). In conclusion, the incidence of CIED-related admissions was 4.3% and increased over time. Further studies are required to determine if the observed temporal increase in incidence of CIED implantations (particularly implantable cardioverter-defibrillators) is associated with a concomitant increase in incidence of aborted sudden cardiac death.

Tetralogy of Fallot with concurrent patent foramen ovale and tricuspid valve dysplasia in a dog.

The echocardiographic findings of a young Pomeranian-cross dog with tetralogy of Fallot, patent foramen ovale, and tricuspid valve dysplasia are described. Ongoing medical management of hypoxemia and erythrocytosis was carried out and the dog survived to 2 years of age. Treatment options for tetralogy of Fallot are discussed.

Tétralogie de Fallot avec persistance du foramen ovale et dysplasie de la valve tricuspide concomitante chez un chien. Les constatations écho-cardiographiques chez un chien Poméranien de race croisée atteint de la tétralogie de Fallot, de la persistance du foramen ovale et d'une dysplasie de la valve tricuspide sont décrites. Une gestion médicale constante de l'hypoxémie et de l'érythrocytose a été réalisée et le chien a survécu jusqu'à l'âge de 2 ans. Les options de traitement pour la tétralogie de Fallot sont discutées.(Traduit par Isabelle Vallières).

Bilateral Hypoglossal Nerve Palsy in an Adult Patient With Repaired Tetralogy of Fallot.

INTRODUCTION: Spontaneous cervical artery dissection (sCAD) is a major cause of ischemic stroke in young and middle-aged adults, but the occurrence of multiple sCADs could suggest the presence of an underlying arteriopathy. Bilateral hypoglossal nerve palsy caused by extracranial internal carotid artery dissections have been rarely described. We present the case of a 3-vessel sCAD in a patient with repaired tetralogy of Fallot (ToF). CASE REPORT: A 50-year-old man was admitted to our stroke unit for a sudden onset of left cervical pain, mild left ptosis, dysarthria, and dysphagia. His medical history was remarkable for surgically repaired ToF. Neurological examination showed left Claude-Bernard-Horner syndrome and bilateral hypoglossal palsy. Diffusion-weighted magnetic resonance imaging excluded parenchymal lesions while magnetic resonance angiography showed a pattern of bilateral extracranial internal carotid and right vertebral dissection. CONCLUSIONS: This is the first case of multiple-vessel sCAD, and more associated with an unusual clinical presentation, in a patient with surgically repaired ToF, supporting the hypothesis that defective large artery elastogenesis plays a role in this congenital disorder, and suggesting the importance of continuous long-term vascular follow-up.

Quality Indicator Completion Rates for Adults with Tetralogy of Fallot.

Quality indicators for adult congenital heart disease (ACHD) were recently published due to a lack of consensus regarding delivery of care to adults with congenital heart disease (CHD). The objective of this study was to examine adherence to quality indicators for the care of patients with tetralogy of Fallot. Adults with tetralogy of Fallot seen in outpatient cardiology clinics at a tertiary care facility between July 2014 and June 2015 were included, and electronic medical records for each visit were reviewed. Completion rates for eight proposed quality indicator metrics were recorded and results for ACHD and non-ACHD cardiologists were compared. A total of 96 eligible patients completed 179 cardiology visits (134 ACHD and 45 non-ACHD). The quality indicator completion rates were over 80% for 7 of the 8 indicators. Metric 5 (cardiac magnetic resonance imaging every five years) had the lowest completion rate at 38.7%. Compared to non-ACHD cardiologists, ACHD cardiologists had higher completion rates for QRS assessment (88.1% vs. 75.6%, p = 0.04), echocardiogram by CHD expert (97.8% vs. 80.0%, p < 0.001), and infective endocarditis counseling (95.9% vs. 77.4%, p = 0.001). In this single center study, there was a wide range of quality indicator completion rates for tetralogy of Fallot. Routine cardiac MRI by an expert in CHD was identified as an area for improvement. There were significant differences in quality indicator completion between ACHD and non-ACHD cardiologists.

Primary repair versus surgical and transcatheter palliation in infants with tetralogy of Fallot.

OBJECTIVES: Treatment of infants with tetralogy of Fallot (ToF) has evolved in the last two decades with increasing use of primary surgical repair (PrR) and transcatheter right ventricular outflow tract palliation (RVOTd), and fewer systemic-to-pulmonary shunts (SPS). We aim to report contemporary results using these treatment options in a comparative study. METHODS: This a retrospective study using data from the UK National Congenital Heart Disease Audit. All infants (n=1662, median age 181 days) with ToF and no other complex defects undergoing repair or palliation between 2000 and 2013 were considered. Matching algorithms were used to minimise confounding due to lower age and weight in those palliated. RESULTS: Patients underwent PrR (n=1244), SPS (n=311) or RVOTd (n=107). Mortality at 12 years was higher when repair or palliation was performed before the age of 60 days rather than after, most significantly for primary repair (18.7% vs 2.2%, P<0.001), less so for RVOTd (10.8% vs 0%, P=0.06) or SPS (12.4% vs 8.3%, P=0.2). In the matched groups of patients, RVOTd was associated with more right ventricular outflow tract (RVOT) reinterventions (HR=2.3, P=0.05 vs PrR, HR=7.2, P=0.001 vs SPS) and fewer pulmonary valve replacements (PVR) (HR=0.3 vs PrR, P=0.05) at 12 years, with lower mortality after complete repair (HR=0.2 versus PrR, P=0.09). CONCLUSIONS: We found that RVOTd was associated with more RVOT reinterventions, fewer PVR and fewer deaths when compared with PrR in comparable, young infants, especially so in those under 60 days at the time of the first procedure.

Exercise training in adults with repaired tetralogy of Fallot: A randomized controlled pilot study of continuous versus interval training.

INTRODUCTION: Adults with repaired tetralogy of Fallot (ToF) have impaired exercise capacity, vascular and cardiac autonomic function, and quality of life (QoL). Specific effects of high-intensity interval or moderate continuous exercise training on these parameters in adults with repaired ToF remain unknown. METHODS AND RESULTS: Thirty adults with repaired ToF were randomized to either high-intensity interval, moderate intensity continuous training (36 sessions, 2-3 times a week) or usual care (no supervised exercise). Exercise capacity, flow-mediated vasodilation, pulse wave velocity, NT-proBNP and fibrinogen levels, heart rate variability and recovery, and QoL (SF-36 questionnaire) were determined at baseline and after the intervention period. Twenty-seven patients (mean age 39±9years, 63% females, 9 from each group) completed this pilot study. Both training groups improved in at least some parameters of cardiovascular health compared to no exercise. Interval-but not continuous-training improved VO2peak (21.2 to 22.9ml/kg/min, p=0.004), flow-mediated vasodilation (8.4 to 12.9%, p=0.019), pulse wave velocity (5.4 to 4.8m/s, p=0.028), NT-proBNP (202 to 190ng/L, p=0.032) and fibrinogen levels (2.67 to 2.46g/L, p=0.018). Conversely, continuous-but not interval-training improved heart rate variability (low-frequency domain, 0.32 to 0.22, p=0.039), heart rate recovery after 2min post-exercise (40 to 47 beats, p=0.023) and mental domain of SF-36 (87 to 95, p=0.028). CONCLUSION: Both interval and continuous exercise training modalities were safe. Interval training seems more efficacious in improving exercise capacity, vascular function, NT-proBNP and fibrinogen levels, while continuous training seems more efficacious in improving cardiac autonomic function and QoL. (Clinicaltrials.gov, NCT02643810).

Stenting of the Right Ventricular Outflow Tract Promotes Better Pulmonary Arterial Growth Compared With Modified Blalock-Taussig Shunt Palliation in Tetralogy of Fallot-Type Lesions.

OBJECTIVES: This study sought to compare pulmonary arterial (PA) growth during palliation after right ventricular outflow tract (RVOT) stenting versus modified Blalock-Taussig shunt (mBTS) in patients coming forward for complete repair of tetralogy of Fallot-type lesions. BACKGROUND: RVOT stenting is a recent alternative to mBTS in the initial palliation of selected patients with Fallot-type lesions. METHODS: This was a retrospective, single-center study of nonrandomized, consecutive palliated Fallot patients over a 10-year period. Differential left PA (LPA) and right PA (RPA) growth was assessed by serial echocardiograms in 67 patients after mBTS (n = 28) or RVOT stent (n = 39). Statistical data analysis was performed using mixed model analysis. RESULTS: RPA z-scores in the mBTS group improved from median -2.41 (interquartile range [IQR]: -2.97 to -1.32) to -1.13 (IQR: -1.68 to -0.59). LPA z-scores improved from -1.89 (IQR: -2.33 to -1.12) to -0.32 (IQR: -0.88 to -0.05). In the RVOT stenting group RPA z-scores improved from -2.28 (IQR: -3.28 to -1.82) to -0.72 (IQR: -1.27 to +0.48), and LPA z-scores from -2.08 (IQR: -2.90 to -0.61) to -0.05 (IQR: -0.88 to +0.48). Mixed model analysis showed significantly better RPA and LPA growth after RVOT stenting. The benefit of RVOT stenting versus mBTS was 0.599 z-scores for the LPA and 0.749 z-scores for the RPA. Rise in oxygen saturations was greater with RVOT stenting (p = 0.012). Median time to complete repair was shorter in the RVOT stent group (227 [142 to 328] days) compared with the mBTS group (439 [300 to 529] days; p < 0.0003). CONCLUSIONS: RVOT stenting promotes better pulmonary arterial growth and oxygen saturations compared with mBTS in the initial palliation of Fallot-type lesions.

Conventional and right-sided screening for subcutaneous ICD in a population with congenital heart disease at high risk of sudden cardiac death.

BACKGROUND: Information regarding suitability for subcutaneous defibrillator (sICD) implantation in tetralogy of Fallot (ToF) and systemic right ventricle is scarce and needs to be further explored. The main objective of our study was to determine the proportion of patients with ToF and systemic right ventricle eligible for sICD with both, standard and right-sided screening methods. Secondary objectives were: (i) to study sICD eligibility specifically in patients at high risk of sudden cardiac death, (ii) to identify independent predictors for sICD eligibility, and (iii) to compare the proportion of eligible patients in a nonselected ICD population. METHODS: We recruited 102 patients with ToF, 33 with systemic right ventricle, and 40 consecutive nonselected patients. Conventional electrocardiographic screening was performed as usual. Right-sided alternative screening was studied by positioning the left-arm and right-arm electrodes 1 cm right lateral of the xiphoid midline. The Boston Scientific ECG screening tool was utilized. RESULTS: In high-risk patients with ToF, eligibility was higher with right-sided screening in comparison with standard screening (61% vs. 44%; p = .018). Eligibility in high-risk right ventricle population was identical with both screening methods (77%, p = ns). The only independent predictor for sICD eligibility was QRS duration. CONCLUSION: In high-risk patients with ToF, right-sided implantation of the sICD could be an alternative to a conventional ICD. In patients with a systemic right ventricle, implantation of a sICD is an alternative to a conventional sICD.