Incidence and risk factors of post-operative arrhythmias and sudden cardiac death after atrioventricular septal defect (AVSD) correction: Up to 47 years of follow-up

Outcomes of atrioventricular septal defects with and without down syndrome: analysis of the national inpatient database

BACKGROUND

Controversial data exist about the impact of Down syndrome on outcomes after surgical repair of atrioventricular septal defect.

AIMS

(A) assess trends and outcomes of atrioventricular septal defect with and without Down syndrome and (B) determine risk factors associated with adverse outcomes after atrioventricular septal defect repair.

METHODS

We queried The National Inpatient Sample using International Classification of Disease codes for patients with atrioventricular septal defect < 1 year of age from 2000 to 2018. Patients' characteristics, co-morbidities, mortality, and healthcare utilisation were evaluated by comparing those with versus without Down syndrome.

RESULTS

In total, 2,318,706 patients with CHD were examined; of them, 61,101 (2.6%) had atrioventricular septal defect. The incidence of hospitalisation in infants with atrioventricular septal defect ranged from 4.5 to 7.5% of all infants hospitalised with CHD per year. A total of 33,453 (54.7%) patients were associated with Down syndrome. Double outlet right ventricle, coarctation of the aorta, and tetralogy of Fallot were the most commonly associated with CHD in 6.9, 5.7, and 4.3% of patients, respectively. Overall atrioventricular septal defect mortality was 6.3%. Multivariate analysis revealed that prematurity, low birth weight, pulmonary hypertension, and heart block were associated with mortality. Down syndrome was associated with a higher incidence of pulmonary hypertension (4.3 versus 2.8%, p < 0.001), less arrhythmia (6.6 versus 11.2%, p < 0.001), shorter duration for mechanical ventilation, shorter hospital stay, and less perioperative mortality (2.4 versus 11.1%, p < 0.001).

CONCLUSION

Trends in atrioventricular septal defect hospitalisation had been stable over time. Perioperative mortality in atrioventricular septal defect was associated with prematurity, low birth weight, pulmonary hypertension, heart block, acute kidney injury, and septicaemia. Down syndrome was present in more than half of atrioventricular septal defect patients and was associated with a higher incidence of pulmonary hypertension but less arrhythmia, lower mortality, shorter hospital stay, and less resource utilisation.

Catheter ablation of atrial tachyarrhythmias in patients with atrioventricular septal defect

AIMS

The incidence of atrial tachyarrhythmias is high in patients with atrioventricular septal defect (AVSD). No specific data on catheter ablation have been reported so far in this population. We aimed to describe the main mechanisms of atrial tachyarrhythmias in patients with AVSD and to analyse outcomes after catheter ablation.

METHODS AND RESULTS

This observational multi-centric cohort study enrolled all patients with AVSD referred for catheter ablation of an atrial tachyarrhythmia at six tertiary centres from 2004 to 2022. The mechanisms of the different tachyarrhythmias targeted were described and outcomes were analysed. Overall, 56 patients (38.1 ± 17.4 years, 55.4% females) were included. A total of 87 atrial tachyarrhythmias were targeted (mean number of 1.6 per patient). Regarding main circuits involved, a cavo-annular isthmus-dependent intra-atrial re-entrant tachycardia (IART) was observed in 41 (73.2%) patients and an IART involving the right lateral atriotomy in 10 (17.9%) patients. Other tachyarrhythmias with heterogeneous circuits were observed in 13 (23.2%) patients including 11 left-sided and 4 right-sided tachyarrhythmias. Overall, an acute success was achieved in 54 (96.4%) patients, and no complication was reported. During a mean follow-up of 2.8 ± 3.8 years, 22 (39.3%) patients had at least one recurrence. Freedom from atrial tachyarrhythmia recurrences was 77.5% at 1 year. Among 15 (26.8%) patients who underwent repeated ablation procedures, heterogeneous circuits including bi-atrial and left-sided tachyarrhythmias were more frequent.

CONCLUSION

In patients with AVSD, most circuits involve the cavo-annular isthmus, but complex mechanisms are frequently encountered in patients with repeated procedures. The acute success rate is excellent, although recurrences remain common during follow-up.

Does Down syndrome influence the outcomes of congenital cardiac surgery? A systematic review and meta-analysis

BACKGROUND

Congenital cardiac surgery for individuals with Down syndrome (DS) has historically occurred at a reduced frequency. Little data are available regarding long-term post-congenital cardiac surgical outcomes. Limited sample sizes and clinical heterogeneity require a pooled analysis approach.

AIMS

To compare long-term outcomes post-congenital heart surgery between adults with and without DS.

METHODS

Databases (Medline, Embase, and PubMed) were searched utilizing terms related to DS and congenital heart disease.Studies that enrolled adults (>18 years) with operated congenital heart disease and compared long-term outcomes with respect to DS presence were included. All study designs were included, but those with limited/peri-operative follow-up, non-English texts, case studies, and literature reviews were excluded.Blinded screening, data extraction, and quality assessment were independently conducted by two reviewers. QUIPS criteria were used for risk of bias analysis. Both random- and fixed-effects models were used for meta-analysis.

RESULTS

A total of 23 studies (n = 10 466) were included. Risk of bias was frequently high due to unblinded retrospective study designs and analyses limited in adjustment for other prognostic factors.Meta-analysis demonstrated no effect of DS on long-term mortality [hazard ratio (HR) 0.86, 95% confidence interval (95% CI) 0.6-1.23], to a maximum described follow-up of 38 years. Lower cardiac reoperation risk (HR 0.6, 95% CI 0.46-0.78) for individuals with DS was found on pooled analysis. Meta-analysis was limited by between-study variation.

CONCLUSION

DS does not affect post-congenital cardiac surgical survival in adulthood. Reduced reoperation may reflect challenges in assessing functional and symptomatic status and/or concerns regarding perceived reoperation difficulties or likely benefits.

Cardiovascular Complications of Down Syndrome: Scoping Review and Expert Consensus

Cardiovascular disease is a leading cause of morbidity and mortality in individuals with Down syndrome. Congenital heart disease is the most common cardiovascular condition in this group, present in up to 50% of people with Down syndrome and contributing to poor outcomes. Additional factors contributing to cardiovascular outcomes include pulmonary hypertension; coexistent pulmonary, endocrine, and metabolic diseases; and risk factors for atherosclerotic disease. Moreover, disparities in the cardiovascular care of people with Down syndrome compared with the general population, which vary across different geographies and health care systems, further contribute to cardiovascular mortality; this issue is often overlooked by the wider medical community. This review focuses on the diagnosis, prevalence, and management of cardiovascular disease encountered in people with Down syndrome and summarizes available evidence in 10 key areas relating to Down syndrome and cardiac disease, from prenatal diagnosis to disparities in care in areas of differing resource availability. All specialists and nonspecialist clinicians providing care for people with Down syndrome should be aware of best clinical practice in all aspects of care of this distinct population.

The influence of age and weight on the outcomes of complete atrioventricular septal defect repair

Background

The appropriate age and weight for surgical repair of atrioventricular septal defect (AVSD) is an area of controversy. We aimed to study the effect of weight and age at the time of surgical repair for complete AVSD in children less than 2 years of age on postoperative outcomes. A retrospective data review was performed for patients who underwent the AVSD repair from 2012 to 2019 at our institutions. Our primary outcome was the postoperative in-hospital length of stay (LOS). Secondary outcomes included total positive pressure ventilation (PPV), ventilation time, maximum vasoactive–inotropic score (max VIS), and other postoperative complications.

Results

The study included fifty patients. The median age was 191 days, and the median weight was 4.38 kg at the time of surgery. Weight < 4 kg was associated with longer PPV time and postoperative in-hospital LOS (p value of 0.033 and 0.015, respectively). Additionally, they had higher max VIS at 24 h and 48 h than the other groups with bodyweight 4–5.9 kg or ≥ 6 kg (p value of 0.05 and 0.027, respectively). Patients with older age or lower weight at operation had a longer in-hospital LOS and total length of PPV after surgery. There were no postoperative in-hospital deaths.

Conclusions

Older age and lower weight at the time of surgical repair of atrioventricular septal defect could be independent predictors of prolonged postoperative in-hospital length of stay and total length of positive pressure ventilation.

Canadian Cardiovascular Society 2022 Guidelines for Cardiovascular Interventions in Adults With Congenital Heart Disease

Interventions in adults with congenital heart disease (ACHD) focus on surgical and percutaneous interventions in light of rapidly evolving ACHD clinical practice. To bring rigour to our process and amplify the cumulative nature of evidence ACHD care we used the ADAPTE process; we systematically adjudicated, updated, and adapted existing guidelines by Canadian, American, and European cardiac societies from 2010 to 2020. We applied this to interventions related to right and left ventricular outflow obstruction, tetralogy of Fallot, coarctation, aortopathy associated with bicuspid aortic valve, atrioventricular canal defects, Ebstein anomaly, complete and congenitally corrected transposition, and patients with the Fontan operation. In addition to tables indexed to evidence, clinical flow diagrams are included for each lesion to facilitate a practical approach to clinical decision-making. Excluded are recommendations for pacemakers, defibrillators, and arrhythmia-directed interventions covered in separate designated documents. Similarly, where overlap occurs with other guidelines for valvular interventions, reference is made to parallel publications. There is a paucity of high-level quality of evidence in the form of randomized clinical trials to support guidelines in ACHD. We accounted for this in the wording of the strength of recommendations put forth by our national and international experts. As data grow on long-term follow-up, we expect that the evidence driving clinical practice will become increasingly granular. These recommendations are meant to be used to guide dialogue between clinicians, interventional cardiologists, surgeons, and patients making complex decisions relative to ACHD interventions.

Incidence, Risk Factors, and Outcomes of Atrial Arrhythmias in Adult Patients With Atrioventricular Septal Defect

OBJECTIVES

This study aimed to assess the incidence, associated factors, and outcomes of atrial arrhythmias in adults with atrioventricular septal defect (AVSD).

BACKGROUND

Data regarding atrial arrhythmias in adults with AVSD are particularly scarce.

METHODS

Data were analyzed from a multicentric cohort of adult patients with AVSD. Lifetime cumulative incidences of atrial arrhythmias were studied. Multiple logistic regression models were used to identify risk factors.

RESULTS

A total of 391 patients (61.6% women) were enrolled with a mean age of 36.3 ± 16.3 years and a mean follow-up of 17.3 ± 14.2 years after initial surgical repair. Overall, 98 patients (25.1%) developed at least 1 episode of atrial arrhythmia at a mean age of 39.2 ± 17.2 years. The mean ages of patients at first episode of intra-atrial re-entrant tachycardia (IART)/ focal atrial tachycardia (FAT) and atrial fibrillation were 33.7 ± 15.3 and 44.3 ± 16.5 years, respectively. The lifetime risks for developing atrial arrhythmia to ages 20, 40, and 60 years were 3.7%, 17.8%, and 55.3%, respectively. IART/FAT was the leading arrhythmia until the age of 45, then atrial fibrillation surpassed IART/FAT. Age (odds ratio [OR]: 1.4; 95% confidence interval [CI]: 1.2-1.6), number of cardiac surgeries (OR: 4.1; 95% CI: 2.5-6.9), left atrial dilatation (OR: 3.1; 95% CI: 1.4-6.8), right atrial dilatation (OR: 4.1; 95% CI: 1.7-10.3), and moderate or severe left atrioventricular valve regurgitation (OR: 3.7; 95% CI: 1.2-11.7) were independently associated with a higher risk of atrial arrhythmias, whereas the type of AVSD and the age at repair were not. The occurrence of atrial arrhythmias was associated with pacemaker implantation (41.8% vs. 8.5%; P < 0.001), heart failure (24.5% vs. 1.0%; P < 0.001), and cerebrovascular accidents (11.2% vs. 3.4%; P = 0.007).

CONCLUSIONS

The lifetime risk of atrial arrhythmias in patients with AVSD is considerable with more than half of patients developing ≥1 atrial arrhythmia by the age of 60 and is associated with a significant morbidity. The risk in partial/intermediate AVSD is as high as in complete AVSD and is not impacted by age at repair.

Altered ascending aortic wall shear stress in patients with corrected atrioventricular septal defect: a comprehensive cardiovascular magnetic resonance and 4D flow MRI evaluation

AIM

In patients after atrioventricular septal defect correction, altered geometry leads to a changed position and subsequent flow over the left ventricular outflow tract. We hypothesised that this altered flow may influence haemodynamics in the ascending aorta.

METHODS

In total, 30 patients after atrioventricular septal defect correction (age 27.6 ± 12.8 years) and 28 healthy volunteers (age 24.8 ± 13.7 years) underwent 4D flow cardiovascular magnetic resonance. Left ventricular ejection fraction and mean and peak wall shear stress calculated at ascending aortic peak systole were obtained from cardiovascular magnetic resonance. Left ventricular outflow tract data including velocity and diameter were obtained from echocardiography.

RESULTS

Patients showed a higher mean (911 ± 173 versus 703 ± 154 mPa, p = 0.001) and peak ascending aortic wall shear stress (1264 ± 302 versus 1009 ± 240 mPa, p = 0.001) compared to healthy volunteers. Increased blood flow velocities over the left ventricular outflow tract (1.49 ± 0.30 m/s versus 1.22 ± 0.20 m/s, p &lt; 0.001) correlated well with mean and peak ascending aortic wall shear stress (r = 0.67, p &lt; 0.001 and r = 0.77, p &lt; 0.001).

CONCLUSION

After atrioventricular septal defect correction, increased wall shear stress was observed, which correlated to velocities over the left ventricular outflow tract. These findings imply that altered outflow tract geometry contributes to changed aortic haemodynamics.

Dysrhythmias in patients with a complete atrioventricular septal defect: From surgery to early adulthood

Objective

Outcomes after surgical repair of complete atrioventricular septal defect (cAVSD) have improved. With advancing age, the risk of development of dysrhythmias may increase. The aims of this study were to (1) examine development of sinus node dysfunction (SND), atrial and ventricular tachyarrhythmias, and (2) study progression of atrioventricular conduction abnormalities in young adult patients with repaired cAVSD.

Study design

In this retrospective multicenter study, 74 patients (68% female) with a cAVSD repaired in childhood were included. Patients’ medical files were evaluated for occurrence of SND, atrioventricular conduction block (AVB), atrial and ventricular tachyarrhythmias.

Results

Median age at repair was 6 months (interquartile range 3‐10) and median age at last follow‐up was 24 years (interquartile range 21‐28). SND occurred after a median of 17 years (interquartile range 11‐19) after repair in 23% of patients, requiring pacemaker implantation in two patients (12%). Regular supraventricular tachycardia was observed in three patients (4%). Atrial fibrillation and ventricular tachyarrhythmias were not observed. Twenty‐seven patients (36%) had first‐degree AVB, which was self‐limiting in 16 (59%) and persistent in 10 (37%) patients. One patient developed third‐degree AVB 7 days after left atrioventricular valve replacement. Spontaneous type II second‐degree AVB occurred in a 28‐year‐old patient. Both patients underwent pacemaker implantation.

Conclusions

Clinically significant dysrhythmias were uncommon in young adult patients after cAVSD repair. However, three patients required pacemaker implantation for either progression of SND or spontaneous type II second‐degree AVB. Longer follow‐up should point out whether dysrhythmias will progress or become more prevalent with increasing age.

Cardiovascular disease in Down syndrome

PURPOSE OF REVIEW

In the last 40 years, with a better understanding of cardiac defects, and with the improved results of cardiac surgery, the life expectancy of persons with Down syndrome has significantly increased. This review article reports on advances in knowledge of cardiac defects and cardiovascular system of persons with trisomy 21.

RECENT FINDINGS

New insights into the genetics of this syndrome have improved our understanding of the pathogenetic mechanisms of cardiac defects. Recent changes in neonatal prevalence of Down syndrome suggest a growing number of children with cardiac malformations, in particular with simple types of defects. Ethnic and sex differences of the prevalence of specific types of congenital heart disease (CHD) have also been underlined. A recent study confirmed that subclinical morphologic anomalies are present in children with trisomy 21, also in the absence of cardiac defects, representing an internal stigma of Down syndrome. The results of cardiac surgery are significantly improved in terms of immediate and long-term outcomes, but specific treatments are indicated in relation to pulmonary hypertension. Particular aspects of the cardiovascular system have been described, clarifying a reduced sympathetic response to stress but also a 'protection' from atherosclerosis and arterial hypertension in these patients.

SUMMARY

Continuing dedication to clinical and basic research studies is essential to further improve survival and the quality of life from childhood to adulthood of patients with trisomy 21.