An unmet need: arrhythmia detection by implantable loop recorder in the systemic right ventricle.

AIMS: Patients with systemic right ventricles are at high risk of sudden cardiac death. Arrhythmia is a significant risk factor. Routine Holter monitoring is opportunistic with poor adherence. The aim of this study was to determine if continuous rhythm monitoring with an implantable loop recorder (ILR) could allow early detection of clinically important arrhythmias. METHODS AND RESULTS: Implantable loop recorder implantation was offered to patients with atrial switch repair for transposition of the great arteries. Recordings were made with symptoms or, automatically for pauses, significant bradycardia or tachycardia and reviewed by the multi-disciplinary team. Twenty-four out of 36 eligible patients underwent ILR implantation with no complication. Forty-two per cent had preserved ventricular function, 75% were NYHA functional class I, 88% had low sudden cardiac death risk, 33% had previous intra-atrial re-entrant tachycardia (IART), and none had known conduction disease. Eighteen out of 24 (75%) patients made 52 recordings (52% automated) over 39.5 months (1.6-72.5). Thirty-two out of 52 (62%) recordings in 15/24 (63%) of the cohort were clinically significant and included sinus node disease (two patients), atrioventricular block (two patients), IART (seven patients), and IART with sinus node disease or atrioventricular block (four patients). Implantable loop recorder recordings prompted medication change in 11 patients [beta-blockers (n = 9), anti-coagulation (n = 5), and stopping anti-coagulation (n = 1)] and device therapy recommendation in seven patients [five pacemakers (three: atrioventricular block) and two defibrillators]. Two patients declined intervention; one suffered an arrhythmic death. Intra-atrial re-entrant tachycardia and clinically relevant conduction disease were detected in patients irrespective of sudden cardiac death risk. CONCLUSION: Continuous monitoring with an ILR in patients with systemic right ventricle following atrial switch detects clinically relevant arrhythmias that impact decision-making. In this cohort, clinically relevant arrhythmias did not correlate with sudden cardiac death risk.

Post-infarction ventricular septal defect: percutaneous or surgical management in the UK national registry.

AIMS: Post-infarction ventricular septal defect (PIVSD) is a mechanical complication of acute myocardial infarction (AMI) with a poor prognosis. Surgical repair is the mainstay of treatment, although percutaneous closure is increasingly undertaken. METHODS AND RESUTS: Patients treated with surgical or percutaneous repair of PIVSD (2010-2021) were identified at 16 UK centres. Case note review was undertaken. The primary outcome was long-term mortality. Patient groups were allocated based upon initial management (percutaneous or surgical). Three-hundred sixty-two patients received 416 procedures (131 percutaneous, 231 surgery). 16.1% of percutaneous patients subsequently had surgery. 7.8% of surgical patients subsequently had percutaneous treatment. Times from AMI to treatment were similar [percutaneous 9 (6-14) vs. surgical 9 (4-22) days, P = 0.18]. Surgical patients were more likely to have cardiogenic shock (62.8% vs. 51.9%, P = 0.044). Percutaneous patients were substantially older [72 (64-77) vs. 67 (61-73) years, P < 0.001] and more likely to be discussed in a heart team setting. There was no difference in long-term mortality between patients (61.1% vs. 53.7%, P = 0.17). In-hospital mortality was lower in the surgical group (55.0% vs. 44.2%, P = 0.048) with no difference in mortality after hospital discharge (P = 0.65). Cardiogenic shock [adjusted hazard ratio (aHR) 1.97 (95% confidence interval 1.37-2.84), P < 0.001), percutaneous approach [aHR 1.44 (1.01-2.05), P = 0.042], and number of vessels with coronary artery disease [aHR 1.22 (1.01-1.47), P = 0.043] were independently associated with long-term mortality. CONCLUSION: Surgical and percutaneous repair are viable options for management of PIVSD. There was no difference in post-discharge long-term mortality between patients, although in-hospital mortality was lower for surgery.

Gender differences in the assessment, decision-making and outcomes for ventricular assist devices and heart transplantation: An analysis from a UK transplant center.

PURPOSE: There are marked gender differences in all etiologies of advanced heart failure. We sought to determine whether there is evidence of gender-specific decision making for transplant assessments, and how gender effects outcomes. METHODS: Retrospective analysis of adult heart transplant assessments at a single UK center between April 2015 and March 2020. RESULTS: Females were 32% of referrals (N = 137 females, 285 males), with marked differences between diagnoses - 11% ischemic and 43% of adult congenital. Females were younger, shorter, weighed less, and had lower pulmonary pressures. Females were much less likely to receive a ventricular assist device (13%). Blood type "O" females were relatively more likely compared to males to receive a transplant (45%). Comparing males and females who received a ventricular assist device, both had similar levels of high pulmonary pressures, indicating consistent decision-making based on hemodynamics to implant a device. Overall survival was better for females (in noncongenital patients), and this was due to female patients who were not accepted for transplant or a ventricular assist device being more often "too well for transplant," rather than in males when they were more often "unsuitable." CONCLUSIONS: Marked gender differences exist at all stages of the heart transplant assessment pathway. Appropriate decision-making based on clinical grounds is shown with less transplants in male blood type "O"s and hemodynamic criteria for ventricular assist device implantation in both genders. Further studies are needed to determine if there is a wider community bias in advanced heart failure treatments for females.

A novel approach to stenting a stenotic graft housing a Berlin Heart cannula by utilizing an adapted left ventricular assist device circuit.

BACKGROUND: A 9-year-old boy with Berlin Heart biventricular assist device for diagnosis of dilated cardiomyopathy developed progressive reduction in left ventricular assist device(VAD) emptying and evidence of low cardiac output despite alterations to the device settings. Computed tomography revealed that the Dacron graft attaching the systemic cannula to the ascending aorta was stenosed. METHOD & RESULT: A minimally invasive approach with novel circuit modification was used to achieve antegrade stenting of the stenosed graft. CONCLUSION: This proposed technique provides a large port for minimally invasive access via an adapted VAD circuit allowing stent insertion to the aortic graft with an excellent outcome.

Mechanical Circulatory Support for the Failing Sub-Aortic Right Ventricle in Adults.

Patients with ccTGA or d-TGA managed via atrial switch (Mustard or Senning operations) have biventricular circulations with a sub-aortic right ventricle (2V-RV). Other than in a tiny percentage of ccTGA patients, premature heart failure (HF) is common, driven by chronic RV dilatation and dysfunction and/or tricuspid regurgitation. These patients are different from the general HF population in that they are younger, more heterogeneous, are predisposed to pulmonary hypertension and present unique and complex surgical challenges. Despite their young age, they experience disproportionately poor access to advanced therapies and are often disqualified for transplant by pulmonary hypertension, HLA sensitization, program risk-tolerance and psychosocial issues. Mechanical support of the subaortic RV with ventricular assist device (subaortic RVAD, also known as SVAD), although technically challenging, can be an effective alternative to palliative care and offers high likelihood of bridging patients to heart transplant candidacy. In addition, temporary trans-catheter SVAD Impella support has been advantageous for stabilization of decompensated 2V-RV patients or as bridge to durable SVAD support. Improved awareness of and access to specialist ACHD-HF teams offering mechanical support (and transplantation) for 2V-RV patients is increasingly urgent for this aging population, and will improve options and outcomes for these patients as HF emerges.

Duct Stenting Versus Modified Blalock-Taussig Shunt in Neonates With Duct-Dependent Pulmonary Blood Flow: Associations With Clinical Outcomes in a Multicenter National Study.

BACKGROUND: Infants born with cardiac abnormalities causing dependence on the arterial duct for pulmonary blood flow are often palliated with a shunt usually between the subclavian artery and either pulmonary artery. A so-called modified Blalock-Taussig shunt allows progress through early life to an age and weight at which repair or further more stable palliation can be safely achieved. Modified Blalock-Taussig shunts continue to present concern for postprocedural instability and early mortality such that other alternatives continue to be explored. Duct stenting (DS) is emerging as one such alternative with potential for greater early stability and improved survival. METHODS: The purpose of this study was to compare postprocedural outcomes and survival to next-stage palliative or reparative surgery between patients undergoing a modified Blalock-Taussig shunt or a DS in infants with duct-dependent pulmonary blood flow. All patients undergoing cardiac surgery and congenital interventions in the United Kingdom are prospectively recruited to an externally validated national outcome audit. From this audit, participating UK centers identified infants <30 days of age undergoing either a Blalock-Taussig shunt or a DS for cardiac conditions with duct-dependent pulmonary blood flow between January 2012 and December 31, 2015. One hundred seventy-one patients underwent a modified Blalock-Taussig shunt, and in 83 patients, DS was attempted. Primary and secondary outcomes of survival and need for extracorporeal support were analyzed with multivariable logistic regression. Longer-term mortality before repair and reintervention were analyzed with Cox proportional hazards regression. All multivariable analyses accommodated a propensity score to balance patient characteristics between the groups. RESULTS: There was an early (to discharge) survival advantage for infants before next-stage surgery in the DS group (odds ratio, 4.24; 95% confidence interval, 1.37-13.14; P=0.012). There was also a difference in the need for postprocedural extracorporeal support in favor of the DS group (odds ratio, 0.22; 95% confidence interval, 0.05-1.05; P=0.058). Longer-term survival outcomes showed a reduced risk of death before repair in the DS group (hazard ratio, 0.25; 95% confidence interval, 0.07-0.85; P=0.026) but a slightly increased risk of reintervention (hazard ratio, 1.50; 95% confidence interval, 0.85-2.64; P=0.165). CONCLUSIONS: DS is emerging as a preferred alternative to a surgical shunt for neonatal palliation with evidence for greater postprocedural stability and improved patient survival to destination surgical treatment.

Outcome for children following admission to hospital with a first episode of heart failure, due to heart muscle disease, in the ventricular assist device (VAD) era.

AIMS: Most reports on the outcome of children who present with heart failure, due to heart muscle disease, are from an era when ventricular assist devices were not available. This study provides outcome data for the current era where prolonged circulatory support can be considered for most children. METHODS & RESULTS: Data was retrieved on 100 consecutive children, who presented between 2010 - 2016, with a first diagnosis of unexplained heart failure. Hospital outcome was classified as either death, transplantation, recovery of function or persistent heart failure. Median age at presentation was 24 months and 58% were < 5 years old. Hospital mortality was 12% and 59% received a heart transplant. Most, 79%, of the transplants were carried out on patients with a device. Recovery of function was observed in 18% and 10% stabilised on oral therapy. Eighty-four percent of the deaths occurred in the <5 year old group. Shorter duration of support was associated with survival (34 days in survivors versus 106 in non-survivors, p = 0.01) and 72% were on an assist device at time of death. CONCLUSION: Heart failure in children who require referral to a transplant unit is a serious illness with a high chance of either transplantation or death. Modifications in assist devices will be required to improve safety, especially for children < 5 years old where the donor wait may be prolonged. The identification of children who may recover function requires further study.

Leg pains in CHD: a distressing symptom of a wider problem.

PurposeAnecdotal reports suggest that children and young adults with CHD frequently experience pain in their legs. The purpose of this pilot study, performed by Little Hearts Matter patient organisation, was to assess the burden of leg pains in this group and begin to investigate associated factors and consequences for daily living. METHODS: An internet-based survey was distributed by Little Hearts Matter patient organisation. After anonymisation and collation, responses were analysed and compared with their healthy siblings. RESULTS: Of the 220 patients who responded, 94% reported leg pains compared with 30% of siblings (n=107; p<0.001). In respondents, pain was typically reported to occur in the lower legs or around the knees or ankles, often associated with crying and screaming (49.0%) and most commonly occurring at night-time (82.0%). Individuals taking aspirin and those who were more active were more likely to report leg pains. Older age was associated with leg pain that occurred with stress (p=0.02) and at night (p=0.05). Analgesia (64.1%) or massage (53.9%) was the preferred option for alleviation. There was no gender bias, association with diagnosis, surgical history, and/ or relationship with diagnosed orthopaedic issues. CONCLUSION: Leg pains are more frequent in those with CHD compared with their healthy siblings. Aetiology is uncertain, but pains share many common characteristics with benign "growing pains".

Outcome after transcatheter occlusion of patent ductus arteriosus in infants less than 6 kg: A national study from United Kingdom and Ireland.

OBJECTIVES: This study aimed to report our national experience with transcatheter patent ductus arteriosus (PDA) occlusion in infants weighing <6 kg. BACKGROUND: The technique of transcatheter PDA closure has evolved in the past two decades and is increasingly used in smaller patients but data on safety and efficacy are limited. METHODS: Patients weighing < 6 kg in whom transcatheter PDA occlusion was attempted in 13 tertiary paediatric cardiology units in the United Kingdom and Ireland were retrospectively analyzed to review the outcome and complications. RESULTS: A total of 408 patients underwent attempted transcatheter PDA closure between January 2004 and December 2014. The mean weight at catheterization was 4.9 ± 1.0 kg and mean age was 5.7 ± 3.0 months. Successful device implantation was achieved in 374 (92%) patients without major complication and of these, complete occlusion was achieved in 356 (95%) patients at last available follow-up. Device embolization occurred in 20 cases (5%). The incidence of device related obstruction to the left pulmonary artery or aorta and access related peripheral vascular injury were low. There were no deaths related to the procedure. CONCLUSIONS: Transcatheter closure of PDA can be accomplished in selected infants weighing <6 kg despite the manufacturer's recommended weight limit of 6 kg for most ductal occluders. The embolization rate is higher than previously reported in larger patients. Retrievability of the occluder and duct morphology needs careful consideration before deciding whether surgical ligation or transcatheter therapy is the better treatment option.

Atrial arrhythmia after transcatheter closure of secundum atrial septal defects in patients ≥40 years of age.

AIM: Data on arrhythmia outcome following device closure of atrial septal defect (ASD) are lacking. This study provides medium-term follow-up data on atrial arrhythmias in patients who were ≥40 years of age at the time of transcatheter ASD closure. METHODS AND RESULTS: It is a retrospective review. Mean age of the 159 patients was 57 years. Median follow-up was 3.6 years (range 6 months-10.9 years). Patients were classified, according to arrhythmia status prior to ASD closure, into Group I, no history of atrial arrhythmia (n = 119, mean age 55.5 years); Group II, paroxysmal atrial arrhythmia (n = 18, mean age 55.7 years); and Group III, persistent atrial fibrillation (n = 22, mean age 65.7 years). Group III patients were significantly older, had larger left atrial size, and had higher mean pulmonary arterial pressure than Group I and II patients (P < 0.001). Prior to closure, radiofrequency ablation was carried out in 12/18 (66%) of Group II and 3/22 (14%) of Group III. After device closure, 7 patients (6%) of Group I developed new atrial fibrillation. Fifty per cent (9/18) of Group II but only 9% (2/22) of Group III were in sinus rhythm on follow-up. CONCLUSION: Device closure alone in patients with persistent atrial arrhythmia is not likely to restore sinus rhythm in the medium term. New atrial arrhythmia occurred in 6% of patients who were in sinus rhythm prior to device closure. At least 50% of the patients with paroxysmal atrial arrhythmia continue to have significant atrial arrhythmia following device closure, and the role of ablation prior to closure in patients with a history of arrhythmia requires refinement.

Hybrid transatrial stent insertion for left atrial decompression in hypoplastic left heart syndrome with intact atrial septum.

OBJECTIVES: To describe a novel strategy for the management of infants with hypoplastic left heart syndrome (HLHS) and intact atrial septum. Antenatally diagnosed infants are delivered in cardiac theatre and immediate left atrial decompression (LAD) using hybrid transatrial stent insertion (HTSI) via sternotomy is carried out. BACKGROUND: HLHS with intact atrial septum is a condition incompatible with life following placental separation. Despite a number of reported strategies the survival of these infants remains much worse than those born with an adequate atrial communication. Immediate postnatal LAD is mandatory to allow consideration of active treatment. METHODS: Single institution retrospective review of intention to carry out HTSI for LAD in infants with an antenatal diagnosis of HLHS intact atrial septum. RESULTS: Two patients were delivered by planned caesarean section and transferred immediately to the prepared team in the adjacent cardiothoracic theatre. Birth weights were 3.2 Kg and 2.96 Kg. Clinical condition was poor with mean arterial PaO2 2.8kPa intubated with 100% inspired oxygen. HTSI was performed using premounted 7 × 17 mm stents (Visi-Pro™, eV3 Endovascular, Plymouth, MN). Mean arterial PaO2 improved to 6.2 kPa. Mean time from surgical incision to LAD was 26 min. Bilateral pulmonary artery bands (BPAB) were then placed. No procedural complications occurred and both patients underwent subsequent surgical stage 1 Norwood at 6 and 10 days. CONCLUSIONS: In this high-risk anatomical substrate, careful planning from accurate fetal diagnosis underpins the success of initial management. This early experience suggests that HTSI offers rapid and successful postnatal LAD with no procedural morbidity facilitating successful subsequent palliation. © 2015 Wiley Periodicals, Inc.

Management of the failing Fontan.

With and increasing number of early survivors after the palliation of the single ventricle physiology there is a burgeoning Fontan population worldwide that will pose unique challenges because of the inevitable sequelae related to the absence of the alleged "needless" sub-pulmonic ventricle. The increasing number and older-age single-ventricle patients highlights the results of successful contemporary surgical palliation in children, leading to the development of an adult single-ventricle population with unpredictable socio-economic and health service impacts. The wide variability in clinical status of patients with Fontan circulation reflects not only the broadened spectrum of morphological substrates involved, but also the evolving surgical techniques during the last four decades. This has come in the wake of a gradual understanding of an incredibly tricky physiology. The magnitude of the disease, the physio-pathological mechanisms, and the therapeutic options to optimize the "failing Fontan" status and to delay the irreversible deterioration of "Fontan failure" condition are discussed in this review.

UK multicenter experience using the Gore septal occluder (GSO(TM) ) for atrial septal defect closure in children and adults.

BACKGROUND: Percutaneous closure of atrial defects (ASD) has evolved as the treatment of choice for the majority of defects and patent oval foramens. The Gore Septal Occluder (GSO) is an innovative device consisting mostly of a folded thin GoreTex tube for use in the closure of septal defects. METHODS: Reviewed is the multicenter UK experience of the first 22 ASD occlusions with the GSO(TM) device. All implantations were performed by consultant operators experienced in ASD device closure. The inclusion criterion was the presence of a hemodynamically significant secundum ASD with a diameter of <18 mm. Procedural data and acute and mid-term closure rates were retrospectively matched to a cohort of patients having defect closure using the Amplatzer Septal Occluder(TM) (ASO(TM) ). RESULTS: Acute and 3-month follow-up closure rates for the GSO(TM) were 100% and 100% vs. 100% and 100% closure with the ASO(TM) implants. The difference in paired procedure times was not statistically significant (56 min: GSO(TM) ; 42 min: ASO(TM) device P = ns), nor was the paired difference in fluoroscopic screening times (12 min: GSO(TM) vs. 8.4 min: ASO(TM) , P = ns). One GSO device embolized immediately after deployment and was successfully retrieved at the same procedure. There were no other significant complications in either group. CONCLUSIONS: The GSO(TM) implant can achieve comparable closure rates to the ASO(TM) in small to moderate atrial septal defects after 3 months. Longer fluoroscopy and procedure times are a drawback; however these should improve with familiarity with the implant and deployment system. The larger sheath size was not associated with increased complications in our cohort.

Patent foramen ovale closure with the Gore septal occluder: initial UK experience.

OBJECTIVES: To report procedural outcome and short-term follow-up data for the Gore septal occluder (GSO), a new device for closure of patent foramen ovale (PFO). BACKGROUND: Transcatheter closure of PFO is an established treatment modality but no current device provides a perfect solution. The GSO has a number of design features, which make it potentially attractive for closure of defects in the atrial septum. METHODS: Data from 9 centers in the United Kingdom implanting the GSO device, submitted to an electronic registry for evaluation. RESULTS: Two hundred twenty-nine patients undergoing PFO closure from June 2011 to October 2012 were included. Indications for closure were secondary prevention of paradoxical cerebral emboli (83.4%), migraine (2.1%), platypnoea orthodeoxia (3.9%), and other (10.5%). Median PFO size was 8 mm and 34 and 39%, respectively, had long tunnel anatomy or atrial septal aneurysms. A GSO was successfully implanted in all cases. A single device was used in 98% but in 4 patients the initial device was removed and a second device required. Procedural complications occurred in 3% and later complications (e.g., atrial fibrillation, atrial ectopics, and device thrombus) in 5.7% of cases. All patients have undergone clinical and echocardiographic follow-up and all devices remain in position. Early bubble studies (median 0 months) with Valsalva maneuver in 67.2% were negative in 89%. CONCLUSIONS: The GSO is an effective occlusion device for closure of PFO of all types. Longer-term follow-up particularly to document later closure rates are required.

Paget-Schroetter Syndrome: A Case of a Young Weightlifter.

Venous thoracic outlet syndrome is a rare type of thoracic outlet disorder that is often overlooked. When an upper extremity deep vein thrombosis (UEDVT) occurs due to thoracic outlet compression, it is commonly referred to as Paget-Schroetter syndrome (PSS). The space between the first rib and the clavicle where the subclavian vein passes through is highly vulnerable to compression and injury. This space often undergoes repetitive trauma due to extrinsic compression which ultimately results in scarring and clot formation. This case report reviews the case of a 26-year-old white male who presented with the chief complaint of right arm swelling and soreness after strenuous bench pressing. He went to urgent care and the initial diagnosis was a strained muscle. An ultrasound was ordered, revealing multiple UEDVTs. At this time, the patient was referred to vascular surgery for further management. Recommended management for PSS is to initiate anticoagulation or thrombolytic therapy depending on the timing between the onset of symptoms and diagnosis. Although there is some disagreement on the next steps after thrombolysis, most physicians agree that decompression of the thoracic outlet with first rib resection is the logical next step to prevent clot recurrence. The patient received the above-mentioned therapy and is progressing well with recovery. Recognizing the thoracic outlet as a potential location for pathology and keeping in mind those who have a presentation similar to this case study is extremely important.

Autograft Reoperation Following the Ross Procedure: Evolving Strategies and Future Perspectives.

Background: Pulmonary autograft failure remains a cause of reoperation following the Ross procedure. The aim of this study is to describe our evolving approach to autograft reoperations. Methods: Retrospective study of all patients who underwent a pulmonary autograft reoperation following a Ross procedure between June 1997 and July 2022. Results: Two-hundred and thirty-five Ross procedures were performed. Thirty-six patients (15%) plus one referral underwent an autograft reoperation at a median of 7.8 years (IQR 4.6-13.6). The main indication was: neoaortic root dilatation associated with mild/moderate (n = 12) or severe (n = 8) aortic regurgitation; isolated severe aortic regurgitation (n = 6); infective endocarditis (IE) (n = 8); and aortic root pseudoaneurysm with no history of IE (n = 3). The autograft was spared in 29 cases (78%): 9 patients (24%) underwent aortic valve repair or aortic root remodeling, 15 patients (40%) aortic root reimplantation, 5 patients neoaortic root stabilization with a Personalized External Aortic Root Support (PEARS) sleeve. There were no in-hospital deaths. At a median follow up of 37 months (IQR 8-105), all patients were alive, 30 (81%) were asymptomatic. Eight patients (22%) required nine further reoperations. Estimated freedom from further reoperation was 90%, 72%, and 72% at 12-, 36-, and 60-months. Conclusions: Autograft reoperations following the Ross procedure can be safely performed and do not affect overall survival in the early and mid-term. Valve-sparing autograft replacement is technically feasible but remains at risk of further interventions. Alternative strategies, such as the PEARS sleeve, are becoming increasingly available but requires validation in the long term.

COVID-19 in congenital heart disease (COaCHeD) study.

BACKGROUND: COVID-19 has caused significant worldwide morbidity and mortality. Congenital heart disease (CHD) is likely to increase vulnerability and understanding the predictors of adverse outcomes is key to optimising care. OBJECTIVE: Ascertain the impact of COVID-19 on people with CHD and define risk factors for adverse outcomes. METHODS: Multicentre UK study undertaken 1 March 2020-30 June 2021 during the COVID-19 pandemic. Data were collected on CHD diagnoses, clinical presentation and outcomes. Multivariable logistic regression with multiple imputation was performed to explore predictors of death and hospitalisation. RESULTS: There were 405 reported cases (127 paediatric/278 adult). In children (age <16 years), there were 5 (3.9%) deaths. Adjusted ORs (AORs) for hospitalisation in children were significantly lower with each ascending year of age (OR 0.85, 95% CI 0.75 to 0.96 (p<0.01)). In adults, there were 24 (8.6%) deaths (19 with comorbidities) and 74 (26.6%) hospital admissions. AORs for death in adults were significantly increased with each year of age (OR 1.05, 95% CI 1.01 to 1.10 (p<0.01)) and with pulmonary arterial hypertension (PAH; OR 5.99, 95% CI 1.34 to 26.91 (p=0.02)). AORs for hospitalisation in adults were significantly higher with each additional year of age (OR 1.03, 95% CI 1.00 to 1.05 (p=0.04)), additional comorbidities (OR 3.23, 95% CI 1.31 to 7.97 (p=0.01)) and genetic disease (OR 2.87, 95% CI 1.04 to 7.94 (p=0.04)). CONCLUSIONS: Children were at low risk of death and hospitalisation secondary to COVID-19 even with severe CHD, but hospital admission rates were higher in younger children, independent of comorbidity. In adults, higher likelihood of death was associated with increasing age and PAH, and of hospitalisation with age, comorbidities and genetic disease. An individualised approach, based on age and comorbidities, should be taken to COVID-19 management in patients with CHD.

A spatial human thymus cell atlas mapped to a continuous tissue axis.

T cells develop from circulating precursors, which enter the thymus and migrate throughout specialised sub-compartments to support maturation and selection. This process starts already in early fetal development and is highly active until the involution of the thymus in adolescence. To map the micro-anatomical underpinnings of this process in pre- vs. post-natal states, we undertook a spatially resolved analysis and established a new quantitative morphological framework for the thymus, the Cortico-Medullary Axis. Using this axis in conjunction with the curation of a multimodal single-cell, spatial transcriptomics and high-resolution multiplex imaging atlas, we show that canonical thymocyte trajectories and thymic epithelial cells are highly organised and fully established by post-conception week 12, pinpoint TEC progenitor states, find that TEC subsets and peripheral tissue genes are associated with Hassall's Corpuscles and uncover divergence in the pace and drivers of medullary entry between CD4 vs. CD8 T cell lineages. These findings are complemented with a holistic toolkit for spatial analysis and annotation, providing a basis for a detailed understanding of T lymphocyte development.

A novel approach to paraneoplastic intestinal pseudo-obstruction.

Paraneoplastic neurologic syndromes (PNS) are uncommon, affecting fewer than 1 in 10,000 patients with cancer. PNS, while rare, can cause significant morbidity and impose enormous socio-economic costs, besides severely affecting quality of life. PNS can involve any part of the nervous system and can present as limbic encephalitis, subacute cerebellar ataxias, opsoclonus-myoclonus, retinopathies, chronic intestinal pseudo-obstruction (CIPO), sensory neuronopathy, Lambert-Eaton myasthenic syndrome, stiff-person syndrome, and encephalomyelitis. The standard of care for CIPO includes the use of promotility and anti-secretory agents and the resection of the non-functioning gut segment; all of which can cause significant compromise in the quality of life. There is significant evidence that paraneoplastic neurologic syndromes are associated with antibodies directed against certain nerve antigens. We successfully treated a patient with CIPO in the setting of small cell lung cancer with a combination of rituximab and cyclophosphamide. The patient, who had failed to respond to prokinetic agents, anti-secretory therapy, and multiple resections, responded to the immunomodulatory therapy, with minimal residuals with PEG tube feeding and sustained ostomy output. The use of rituximab and cyclophosphamide should therefore be considered in patients with CIPO, especially if it can avoid complicated surgical procedures.