Cardiac remodeling and effects on exercise capacity after interventional closure of atrial septal defects in different adult age groups

Brazilian Guideline for Exercise Testing in Children and Adolescents - 2024

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LEVELS OF EVIDENCE

The Prevalence of and Predisposing Factors for Late Atrial Arrhythmias after Transcatheter Closure of Secundum Atrial Septal Defects in Children

BACKGROUND

A 24 h Holter study in children after transcatheter secundum ASD (ASD II) closure was conducted to detect the prevalence of defects and/or device-related late atrial arrhythmias (LAAs). ASD II closure with an Amplatzer septal occluder (ASO) is an established procedure. Little is known about LAAs after device implantation.

METHODS

The eligible participants were children who had undergone ASO implantation, with a follow-up of ≥5 years, as well as one pre- and at least one post-procedural Holter ECG.

RESULTS

In total, 161 patients (mean age: 6.2 ± 4.3 years), with a mean follow-up of 12.9 ± 3.1 years (range 5-19), were included. A median of four Holter ECGs per patient were available. LAAs occurred before intervention in four patients (2.5%), and it was peri-interventional in four patients (2.5%), sustained in three patients (1.9%), and developed in three patients (1.9%). In patients with pre- and peri-interventional LAAs, the Qp/Qs ratio was higher (6.4 ± 3.9 vs. non-AA: 2.0 ± 1.1 (p = 0.002)) and the IAS/ASO ratio was lower (1.18 ± 0.27 vs. non-AA: 1.7 ± 0.4 (p < 0.001)). The patients with LAAs differed from those without LAAs in their Qp/Qs (6.8 ± 3.5 vs. 2.0 ± 1.3; p < 0.0001) and IAS/ASO ratios (1.14 ± 0.19 vs. 1.73 ± 0.45; p < 0.001). The patients with LAAs had a Qp/Qs ratio ≥2.94:1, and those who developed LAAs had an IAS/ASO ratio <1.15.

CONCLUSIONS

LAAs occurred in 1.9% of patients and were sustained in another 1.9% of patients but persisted in those with large shunt defects and large occluders in relation to the atrial septal length. The predisposing factors for LAAs after ASD closure were a high Qp/Qs ratio, pre-existing atrial arrhythmias, and a low IAS/ASO ratio.

Prevalence and outcomes of pulmonary hypertension after percutaneous closure of atrial septal defect: a systematic review and meta-analysis

BACKGROUND

Atrial septal defect (ASD) is a common form of congenital heart disease. Significant shunts may increase the risk of developing pulmonary hypertension (PH). We aimed to describe current PH definitions, evaluate PH prevalence and the effect of PH on outcomes in patients undergoing percutaneous ASD closure.

METHODS

EMBASE, MEDLINE and Cochrane databases were systematically searched. Studies reporting PH prevalence or mean systolic pulmonary arterial pressure (sPAP) before and after percutaneous ASD closure in adults were included. We conducted meta-analyses to obtain summary estimates for PH prevalence and mean sPAP.

RESULTS

15 articles with a total of 1073 patients met the eligibility criteria. Studies applied variable PH definitions. PH prevalence and mean sPAP levels decreased in all studies after closure. The pooled PH prevalence decreased from 44% (95% CI 29-60%) to 18% (95% CI 8-27%). The overall standardised mean difference in sPAP was 1.12 (95% CI 0.81-1.44) and 1.62 (95% CI 1.00-2.23) in cohort and case-series studies respectively indicating a large decrease. The pooled standard mean difference among the younger and older patients were different, 1.25 (95% CI 0.78-1.71) and 0.91 (95% CI 0.56-1.27), respectively. A high degree of between-study heterogeneity was noted.

CONCLUSIONS

Both PH prevalence and mean sPAP decrease after ASD closure. Larger, prospective studies with consistent PH definitions using the recommended measurement modality are warranted.

Transcatheter closure of atrial septal defect in adults: time-course of atrial and ventricular remodeling and effects on exercise capacity

Investigate ventricular and atrial remodeling following atrial septal defect (ASD) closure and examine if pulmonary-to-systemic flow ratio (QP/QS) and right ventricular (RV) volume predict improvement, determined as percentage of predicted oxygen uptake (VO₂%). Long-term cardiovascular magnetic resonance (CMR) data on atrial and ventricular remodeling after ASD-closure is limited and treatment effect on exercise capacity is debated. Sixteen patients undergoing transcatheter ASD closure and 16 age and sexmatched controls were studied. CMR was performed before treatment, the day after and 3 and 12 months later. Exercise test with gas analysis was performed before and 12 months after treatment. QP/QS decreased from 2.1 ± 0.5 to 1.4 ± 0.3 at day 1 and 1.1 ± 0.1 at 3 and 12 months. Left ventricular (LV) volumes increased and normalized on day 1 whereas left atrial volumes were unchanged. RV and right atrial volumes decreased the first 3 months. LV and RV volumes had not equalized at 12 months (RV/LV ratio 1.2 ± 0.1, P < 0.01) and RV ejection fraction remained decreased compared to controls. Improvement of VO₂% after ASD closure (P < 0.01) was inversely related to QP/QS at rest (r = - 0.56, P < 0.05) but unrelated to RV end-diastolic volume (P = 0.16). Following transcatheter ASD closure, LV adaptation is rapid and RV adaptation is prolonged, with decreased systolic RV function. Patients with smaller shunts had larger improvement in VO₂% suggesting patients with defects of borderline hemodynamic significance might benefit from closure. This may be due to impaired LV diastolic function influencing shunt size and exercise capacity following ASD closure.

Atrial septal defect and exercise capacity: value of cardio-pulmonary exercise test in assessment and follow-up

Nearly four decades ago, the World Health Organization stated that functional capacity explorations best reflected the impact of a chronic disease on quality of life. Today, cardio-pulmonary exercise test (CPET) is recommended in the follow-up of patients with congenital heart diseases (CHDs). Indeed, the maximum oxygen uptake (VO_2max) and the ventilatory efficiency (VE/VCO₂ slope) correlate with both the prognosis and the quality of life in this population. Atrial septal defects (ASDs) represent the second most frequent CHD and are usually considered as simple CHDs. However, the exercise capacity of ASD patients may be impaired. Therefore, the CPET provides important information in assessment and follow-up of patients with ASDs, for both children and adults. Exercise capacity of patients with unrepaired ASDs depends on the importance of the shunt, the right ventricular (RV) function and volume overload, the level of pulmonary arterial pressure, and the occurrence of arrhythmias. For repaired ASDs, exercise capacity also depends on the delay before closure and the type of procedure (catheter or surgery). In most cases, the exercise capacity is nearly normal and CPET contributes to promote sports participation. In addition, a regular CPET follow-up is necessary to evaluate the occurrence, severity and physiological mechanisms of comorbidities, i.e., heart failure, pulmonary hypertension and arrhythmia. Furthermore, CPET follow-up in patients with ASDs may detect early onset of muscular deconditioning, for which cardiac rehabilitation may be considered.

Changes in blood volume shunting in patients with atrial septal defects: assessment of heart function with cardiovascular magnetic resonance during dobutamine stress

Background

The purpose of this study was to determine the effect of stress on left-to-right shunting in patients with atrial septal defect (ASD) and to investigate if the degree of shunting, cardiac output (CO), and right ventricular (RV) volumes are related to exercise capacity.

Methods

Twenty-six patients with a secundum ASD and 16 healthy volunteers were studied with rest/stress cardiac magnetic resonance using 20 µg/kg/min dobutamine and 0.25–0.75 mg atropine to quantify CO, pulmonary to systemic flow ratio (QP/QS), and left ventricular (LV) and RV volumes. Peak oxygen uptake (VO₂peak) was determined on ergospirometry.

Results

In patients with ASD the QP/QS decreased from 2.0 ± 0.2 at rest to 1.5 ± 0.1 (P < 0.001) during dobutamine stress (n = 20) and shunt volume per heartbeat decreased from 70 ± 9 to 38 ± 9 mL (P < 0.001). However, absolute shunt volume per minute was unchanged (5.1 ± 0.8 vs. 4.5 ± 1.0 L/min, P = 0.32) explained by a higher increase in systemic CO during stress (90 ± 11%) compared with pulmonary CO (43 ± 7%, P < 0.001). In ASD patients, VO₂peak correlated with aortic CO during stress (r = 0.77) and QP/QS at rest (r = −0.48) but not during stress (P = 0.09). VO₂peak did not correlate with RV volumes in patients.

Conclusion

Pulmonary to systemic flow ratio and shunt volume per heartbeat decrease during stress in ASD patients. This may be explained by an enhanced LV diastolic function during stress and may have implications to detect disturbances in LV compliance in ASD patients. A high systemic CO during stress is a strong predictor of exercise capacity.

Impaired exercise capacity following atrial septal defect closure: an invasive study of the right heart and pulmonary circulation

Patients with early repair of an isolated atrial septal defect (ASD) are expected to have unremarkable right ventricular (RV) and pulmonary circulation physiology. Some studies, however, suggest persistent functional impairment. We aimed to examine the role of abnormal RV and pulmonary vascular response to exercise in patients who had undergone ASD closure. Using a previously published data set, we reviewed invasive exercise cardiopulmonary testing with right-sided hemodynamic data for 12 asymptomatic patients who had undergone ASD closure. The 5 (42%) patients with impaired maximal oxygen uptake ([Formula: see text]) were older and exhibited a lower peak cardiac index (5.6 ± 0.8 vs. 9.0 ± 1.2 L/min/m(2); P = .005) because of abnormal stroke volume augmentation (+3.2 ± 3.9 vs. +17.4 ± 10.2 mL/m(2); P = .02). While all resting hemodynamic variables were similar, patients with low [Formula: see text] tended to have abnormal total pulmonary vascular resistance change during exercise (+11% ± 41% vs. -28% ± 26%; P = .06) and had a steeper relation between mean pulmonary arterial pressure and cardiac index (5.8 ± 0.6 vs. 2.2 ± 0.1 L/min/m(2); P = .02). The increase in peak mean RV power during exercise was also significantly lower in the impaired-[Formula: see text] patients (4.7 ± 1.6 vs. 7.6 ± 2.1 J/s; P = .04). As described in the original study, despite normal resting hemodynamics, a subset of asymptomatic patients with repaired ASD had diminished exercise capacity. Our analysis allows us to conclude that this is due to a combination of abnormal pulmonary vascular response to exercise and impaired RV function.

Interventional closure of atrial septal defects without fluoroscopy in adult and pediatric patients

BACKGROUND

Interventional closure of atrial septal defects (ASDs) with a transcatheter device is the preferred strategy in children and adults. This procedure has been proven in numerous studies, but X-ray and contrast agent exposure is still a major side effect. The aim of this study was to clarify whether the interventional closure of ASDs is possible and safe if it is guided by transesophageal echocardiography (TEE) alone.

METHODS AND RESULTS

We retrospectively selected and studied pediatric and adult patients with interventional closure of ASDs at the Deutsches Herzzentrum Berlin (DHZB) without fluoroscopy between 1999 and 2010. We included 330 out of 1,605 patients; 254 had an ASD II, 30 a PFO and 46 multiperforated atrial septum. Median age was 8.92 (0.96-76.3) years and median body weight 32.6 (8.3-156) kg. Median stretched defect size was 13 (5-29) mm. Median procedure time was 50 (20-170) min. Closure was performed in the majority of patients with the Amplatzer(®) septal occluder or Amplatzer(®) PFO occluder. The procedure succeeded in 98.2 % of cases and closure rate was 94.9 % after 48 h. Complication rate was low and procedure time was similar to that necessary with studies using fluoroscopy.

CONCLUSION

Interventional closure of ASDs is safe and effective if guided with TEE alone. The results can compete with those with the use of fluoroscopy. TEE-guided closure of ASD should be considered in more catheter laboratories to avoid unnecessary radiation exposure for the patient and the examiner.

Exercise testing and prescription in patients with congenital heart disease

The present paper provides a review of the literature regarding exercise testing, exercise capacity, and the role of exercise training in patients with congenital heart disease (CHD). Different measures of exercise capacity are discussed, including both simple and more advanced exercise parameters. Different groups of patients, including shunt lesions, pulmonary valvar stenosis, patients after completion of Fontan circulation, and patients with pulmonary arterial hypertension are discussed separately in more detail. It has been underscored that an active lifestyle, taking exercise limitations and potential risks of exercise into account is of utmost importance. Increased exercise capacity in these patients is furthermore correlated with an improvement of objective and subjective quality of life.

Incidence and predictors of atrial fibrillation following transcatheter closure of interatrial septal communications using contemporary devices

Background

Transcatheter closure of interatrial septal communications (IASC) is being increasingly performed, while less is known about predictors and incidence of new onset atrial fibrillation (AF) after device closure. Hitherto, most studies have only analyzed some parameters potentially influencing the occurrence of AF, variously omitting others and thus limiting interpretation of results.

Methods

Descriptive, single author, observational study with 68 consecutive patients [aged 53.6 ± 15.1 years; 32 females (47%)] undergoing IASC closure, being followed up for 16.8 (±9.9; 6–42) months. Two patients with AF previous to device implantation had been excluded. Parameters analyzed included age and gender as well as presence of coronary artery disease, hypertension, atrial size, body mass index, device size, and presence of residual shunt. Device size was normalized to maximal disk diameter as declared by the manufacturer.

Results

The incidence of new onset AF was 10.3% in the first 6 months after IASC closure. The only two predictors linked to AF were device size (P = 0.002) and, although not reaching significance level, right atrial dilatation (P = 0.08).

Conclusion

Occluder size was the only significant predictor of post-procedural AF, especially after PFO closure. Although there may be constraints (defect size, presence of an atrial septal aneurysm) that may dictate implantation of a larger device, it is reasonable to implant them “as large as necessary, as small as possible”. The influence of atrial dimensions on post-procedural onset of AF must be further investigated.