Atrial septal defect in adults: cardiopulmonary exercise capacity before and 4 months and 10 years after defect closure

Long term outcome after surgical ASD-closure at young age: Longitudinal follow-up up to 50 years after surgery

OBJECTIVES

To describe the clinical outcome and quality of life up to 50 years after surgical atrial septal defect (ASD) closure at young age. Primary outcome is defined as MACE (all-cause mortality, cardiac re-interventions, ischemic stroke, endocarditis, heart failure and symptomatic arrhythmia).

METHODS

Single-center, longitudinal cohort-study evaluating 135 consecutive patients who underwent ASD-closure before the age of 15 years between 1968 and 1980. Participants were invited for extensive cardiac evaluation and assessment of quality-of-life every 10 years.

RESULTS

Eighty patients (86%) of 93 eligible survivors were included in this study (mean age 52 ± 5 years (range 41-63), 40% male). Median follow-up since surgery was 45 years (range 40-51). Cumulative survival after 50 years was 86% and comparable to the normal Dutch population. Cumulative event-free survival after 45 and 50-years was 59% and 46% respectively (re-intervention in 6, symptomatic arrhythmia in 25, and pacemaker implantation in 10 patients). Right ventricular ejection fraction on CMR was diminished in 6%. Exercise capacity was normal in 77%. There was no pulmonary hypertension. NT-proBNP was elevated in 61%. Quality of life was comparable with the general population. No predictors for late events were identified.

CONCLUSION

Long-term survival after surgical ASD-closure in childhood is good and not statistically different at 50 years compared to the normal Dutch population. Re-intervention rate is low, there is no pulmonary hypertension. Right ventricular function was diminished in 6%, exercise capacity was good and stable over time with quality of life comparable to the general population. However, supraventricular tachycardia is common.

Late recovery of the cardiopulmonary exercise capacity after transcatheter amplatzer device closures for atrial septal defects in adults

Transcatheter atrial septal defect (ASD) closures using an Amplatzer Septal Occluder (ASO) have been widely performed. Compared to children, we sometimes experience late recovery of exercise performance in adult patients. Our study aimed to evaluate the change in the cardiopulmonary exercise capacity in asymptomatic or mildly symptomatic adult patients after a transcatheter ASD closure using an ASO. The subjects consisted of 29 patients (age 39.5 ± 13.6 years) that underwent cardiopulmonary exercise testing (CPX) before, 3, 6, and 12 months after a transcatheter secundum ASD closure using an ASO. The peak oxygen consumption (peak VO₂), anaerobic threshold (AT), and slope of the correlation between the ventilation and carbon dioxide production (VE/VCO₂ slope) were evaluated. We also evaluated the left-ventricular end-diastolic diameter (LVEDD), right-ventricular end-diastolic dimension (RVEDD) by echocardiography, and hemodynamic values by cardiac catheterization before the ASO procedure. The peak VO₂ did not show any improvement 3 months after the ASO procedure; however, a significant improvement was displayed 6 and 12 months (baseline: 23.4 ± 6.3, 3 months: 23.6 ± 6.4, 6 months: 25.1 ± 5.6, 12 months: 26.4 ± 5.3 mL/kg/min; p < 0.001) after the ASO. The LVEDD (before: 38.1 ± 3.6, 3 months: 43.4 ± 3.4 mm; p < 0.001) and RVEDD (before: 33.6 ± 5.3, 3 months: 26.3 ± 2.6 mm; p < 0.001) on echocardiography quickly improved 3 months after the ASO. Although the LVEDD and RVEDD normalized 3 months after the ASO, the peak VO₂ still decreased; however, the peak VO₂ improved to almost a normal range 6 months after the ASO.

A prospective 5-year study of exercise performance following Melody valve implant

BACKGROUND

The long-term benefits of Melody valve implant for right ventricular outflow tract conduit obstruction or insufficiency on exercise capacity are undefined.

METHODS

As part of the Melody valve clinical trial, 136 patients with congenital heart disease underwent serial cardiopulmonary exercise testing prior to, 6 months after, and annually for up to 5 years postimplant.

RESULTS

Mean age at Melody valve implantation was 22.4 ± 0.9 years (range 7-53 years). The 95 patients who completed the study protocol provide the basis of this report. An initial improvement in % predicted workload was present at 6 months postimplant; however, at the final (5 year) follow-up, sustained or further improvements in workload were not demonstrated for the entire cohort compared to baseline. By subgroup analysis, age <17 years at implant and pulmonary regurgitation as the primary lesion were variables associated with sustained improvement in exercise performance. There were sustained improvements in the ventilatory equivalents for O₂ (minute ventilation/O₂ intake, P = .01) and CO₂ (minute ventilation/CO₂ output, P < .01) at the ventilatory anaerobic threshold at the study conclusion. Improvements in forced vital capacity were also observed during the study but not sustained at the final follow-up.

CONCLUSIONS

A cautious appraisal of the cardiovascular benefits of Melody valve implant on sustained improvements in exercise performance appears warranted. Although the observed changes in pulmonary function suggest improved restrictive lung physiology and more efficient gas exchange, after an initial increase in % predicted performance, neither sustained nor further improvements in exercise performance were observed, except in specific patient subgroups.

Strengths, Limitations, and Geographical Discrepancies in the Eligibility Criteria for Sport Participation in Young Patients With Congenital Heart Disease

OBJECTIVE

Benefits of physical activity has been shown in children with congenital heart disease (CHD). In several forms of CHD, the risk of sudden death remains a major concern both for parents and clinicians, who in turn will have to consider the risk-benefit ratio of sport participation versus restriction.

DATA SOURCE

A literature search was performed within the National Library of Medicine using the keywords: Sport, CHD, and Eligibility. The search was further refined by adding the keywords: Children, Adult, and Criteria.

MAIN RESULTS

Fifteen published studies evaluating sport eligibility criteria in CHD were included. Seven documents from various scientific societies have been published in the past decade but which of them should be adopted remains unclear. Our research highlighted accuracy and consistency of the latest documents; however, differences have emerged between the US and European recommendations. Eligibility criteria were consistent between countries for simple congenital heart defects, whereas there are discrepancies for borderline conditions including moderate valvular lesions and mild or moderate residual defects after CHD repair. Furthermore, some of the more severe defects were not evaluated. Multiple recommendations have been made for the same CHD, and cut-off values used to define disease severity have varied. Published eligibility criteria have mainly focused on competitive sports. Little attention was paid to recreational activities, and the psychosocial consequences of activity restriction were seldom evaluated.

CONCLUSIONS

Comprehensive consensus recommendations for sport eligibility evaluating all CHD types and stages of repair are needed. These should include competitive and recreational activities, use standardized classifications to grade disease severity, and address the consequences of restriction.

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.

Improvement of physical capacity in patients undergoing transcatheter closure of atrial septal defects

INTRODUCTION

Atrial septal defect (ASD) is the most common congenital cardiac anomaly diagnosed in adults. It often remains asymptomatic until the fourth or fifth decade of life. Significant left-to-right interatrial shunting is associated with the risk of heart failure, pulmonary hypertension and atrial fibrillation. Percutaneous ASD closure is a recognized method of treatment.

AIM

To evaluate the clinical outcomes and physical capacity in patients undergoing transcatheter closure of ostium secundum ASD.

MATERIAL AND METHODS

One hundred and twenty adult patients (75 females and 45 males) with a mean age of 43.1 ±13.3 (17-78) years who underwent transcatheter device closure of ostium secundum ASD were analyzed. Clinical evaluation and transthoracic color Doppler echocardiographic study were repeated in all patients before as well as 1 and 24 months after the procedure. To assess the physical capacity symptom-limited treadmill exercise tests with respiratory gas-exchange analysis were performed in all patients before the procedure and after 24 months of follow-up.

RESULTS

The devices were successfully implanted in all patients. During 24 months of follow-up all patients showed significant clinical and spiroergometric improvement of exercise capacity, and a significant decrease of right heart chamber overload features on echocardiography.

CONCLUSIONS

Transcatheter closure of ASD in patients with significant shunt resulted in significant clinical and hemodynamic improvement regardless of the baseline functional class.

Impaired ventilatory efficiency after closure of atrial or ventricular septal defect

OBJECTIVES

Atrial and ventricular septal defects are the most common congenital heart defects and the closing procedures share important similarities. Generally, the postoperative outcome is considered benign, but there is growing concern regarding late ventilatory function. Therefore, the aim of this review was to describe the ventilatory function in patients with open as well as percutaneously or surgically closed atrial and ventricular septal defects.

METHODS

We performed a search protocol based on the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" (PRISMA) guidelines. A data collection form was specifically developed and data were extracted from the included studies by a primary reviewer and cross-checked by the secondary reviewer.

RESULTS

We found an increasing evidence of late impairment in ventilatory efficiency, and despite that ventilatory function is commonly normal at rest, abnormalities were disclosed during exercise. There are indices that surgical closure plays an important role.

DISCUSSION

Atrial septal defect and ventricular septal defect patients have persisting, long-term impairment in ventilatory efficiency during exercise. Although the pathogenesis behind this finding may be multifactorial, there are indices that the surgical procedure may play an important role. Nevertheless, the literature is this field is sparse, and additional studies are needed.

Relationship between atrial septal defects and asthma-like dyspnoea: the impact of transcatheter closure

BACKGROUND

Patients with atrial septal defects (ASD) are often misdiagnosed as asthma patients and accordingly receive erroneous bronchodilator treatment. In order to characterise their symptoms of dyspnoea to explain this clinical observation, we investigated the prevalence of asthma-like symptoms in patients with secundum ASD who then underwent successful percutaneous closure.

METHODS

A total of 80 ASD patients (74 % female, mean age 46.7 ± 16.8 years, median follow-up 3.0 [2.0-5.0] years) retrospectively completed dyspnoea questionnaires determining the presence and extent of cough, wheezing, chest tightness, effort dyspnoea and bronchodilator use on a 7-point scale (0 = none, 6 = maximum) before and after ASD closure. The Mini Asthma Quality of Life (Mini-AQLQ) and Asthma Control Questionnaire with bronchodilator use (ACQ6) were administered.

RESULTS

A total of 48 (60 %) patients reported cough, 27 (34 %) wheezing, 26 (33 %) chest tightness and 62 (78 %) effort dyspnoea. Symptom resolution or reduction was found in 64 (80 %) patients after ASD closure. Asthma symptom scores decreased significantly on the Mini-AQLQ and ACQ6 (both p < 0.001). The number of patients using bronchodilators decreased from 16 (20 %) to 8 (10 %) patients after ASD closure (p = 0.039) with less frequent use of bronchodilators (p = 0.015).

CONCLUSIONS

A high prevalence of asthma-like symptoms and bronchodilator use is present in ASD patients, which exceeds the low prevalence of bronchial asthma in this study population. Future prospective research is required to confirm this phenomenon. The presence of an ASD should be considered in the differential diagnosis of patients with asthma-like symptoms, after which significant symptom relief can be achieved by ASD closure.

[Interventional closure of atrial septal defects, patent oval foramen and ventricular septal defects]

Percutaneous transcatheter closure techniques and devices for congenital intracardiac shunts have considerably improved; therefore, catheter closure is now the treatment of choice for atrial septal defects (ASD). This is technically feasible in more than 80% of patients with a secundum ASD and the success rate is higher than 99%. General anesthesia is as a rule unnecessary and the hospital stay is very short. A patent oval foramen (POF) is a potential cause of cryptogenic stroke and peripheral embolisms. The catheter occlusion has many advantages in comparison to lifelong anticoagulation therapy and for some patients it is the only therapeutic option. Randomized trials have shown that interventional closure leads to results which are comparable to drug therapy and for some occlusion systems even evidence of significant advantages compared to drug therapy was found. Even ventricular septal defects (VSD), including perimembraneous and post-myocardial infarction VSDs can be closed by catheter techniques with a high success rate.

Why exercise capacity does not improve after pulmonary valve replacement

Optimal timing of pulmonary valve replacement (PVR) for pulmonary regurgitation is a debated topic. It is logical that maximal aerobic capacity (VO2peak) would decline when a PVR is needed, but a diminished VO2peak is not always present before PVR, and previous studies show no improvement in VO2peak after PVR. This study aimed to evaluate changes in resting spirometry from pre- to post-PVR sternotomy, to determine the limiting factors of VO2peak before and after PVR, and to determine whether changes in resting lung function after PVR may explain the lack of improvement in VO2peak after surgery. For 26 patients (age, 19.7 ± 7.8 years) with a history of right ventricular outflow tract revision, the study prospectively evaluated echocardiograms, resting spirometry, and maximal exercise tests before PVR and then an average of 15 months after PVR. Flow volume loops were reviewed by a pulmonologist and categorized as obstructive, restrictive, both obstructive and restrictive, or normal. Exercise tests were interpreted using Eschenbacher's algorithm to determine the primary factors limiting exercise. No change in VO2peak or spirometry after PVR was observed. Before PVR, many patients had abnormal resting lung functions (85 % abnormal), which was unchanged after PVR (86 5 % abnormal). The majority of the patients had a ventilatory limitation to VO2peak before PVR (66.7 %), whereas 28.5 % had a cardiovascular limitation, and 4.8 % had no clear limitation. After PVR, 65.2 % of the patients had a ventilatory limitation, whereas 30.4 % had a cardiovascular limitation, and 4.4 % had no clear limitation to VO2peak. Pulmonary function did not change up to 15 months after surgical PVR. The frequency of pulmonary limitation to VO2peak after PVR did not increase. The effect of pulmonary function on exercise-related symptoms must be considered in this patient population. Improved cardiac hemodynamics are unlikely to improve VO2peak in a primarily pulmonary-limited patient.

Latent pulmonary hypertension in atrial septal defect: Dynamic stress echocardiography reveals unapparent pulmonary hypertension and confirms rapid normalisation after ASD closure

Objective

Closure of atrial septal defects (ASD) prevents pulmonary hypertension, right heart failure and thromboembolic stroke. The exact timing for ASD closure is controversial.

Methods

In a prospective study to address the question whether unapparent pulmonary hypertension can be revealed prior to right ventricular (RV) remodelling, patients were investigated before and 6, 12, and 24 months after ASD closure using exercise stress echocardiography (ESE) and ergospirometry (n = 24).

Results

At rest, RV systolic pressure (RVSP) was normal in 58.8 %, slightly elevated in 26.5 %, and moderately elevated in 11.8 %. One patient showed severe pulmonary hypertension. During ESE, all patients with normal RVSP at rest exhibited an increase (25.7 ± 1.2 mmHg vs. 45.3 ± 2.3 mmHg, p < 0.001). After closure the RVSP was lower, both at rest and ESE. RV diameters decreased too. Tricuspid annulus plane systolic excursion (TAPSE) at rest remained lower after closure (24.0 ± 0.9 vs. 22.0 ± 0.9 mm, p < 0.05). TAPSE in ESE was elevated, and stayed stable after closure (30.1 ± 1.8 mm vs. 29.3 ± 1.6 mm). Before closure, RV systolic tissue velocities (s^a) at rest were normal and decreased after closure (14.0 ± 1.0 cm/s vs. 11.5 ± 0.7 (6 month) vs. 10.6 ± 0.5 cm/s (12 month), p < 0.05). During ESE, s^a velocity was similar before and after closure (23.0 ± 1.3 cm/s vs. 23.3 ± 1.9 cm/s). Maximal oxygen uptake (VO₂/kg) did not differ between baseline and follow-ups.

Conclusion

Latent pulmonary hypertension may become apparent in ESE. ASD closure leads to a significant reduction in this stress-induced pulmonary hypertension and to a decrease in the right heart diameters indicating reverse RV remodelling. RV functional parameters at rest did not improve. The VO₂/kg did not change after ASD closure.

Noninvasive cardiac output measurement at rest and during exercise in pediatric patients after interventional or surgical atrial septal defect closure

In the majority of patients, secundum atrial septal defects (ASDs) are treated interventionally or surgically, before the onset of clinical symptoms, between 3 and 6 years of age. Because right-ventricular dimensions usually normalize after ASD closure, it has been assumed that cardiac function and exercise performance also normalize at long-term follow-up. The aim of our study was to determine cardiac index (CI) at rest and during exercise at medium-term follow-up of children who had undergone surgical or interventional closure of ASD because no such reports have been published thus far. Seventeen patients (age range 8.8-17.3 years) who underwent surgical correction were included together with 17 subjects who received an interventional procedure with Amplatzer and Helex occluders (age range 12.2-17.3 years). The study was performed after a median interval of 8.6 years (range 6.5-11.6) after the procedure. Twelve healthy children of comparable age served as controls. CI measurements were performed based on the inert gas-rebreathing method with the Innocor system. For exercise testing, the standard treadmill protocol of the German Society of Pediatric Cardiology was used. CI, stroke volume (SV), and heart rate (HR) were determined at rest and at two standardized submaximal exercise levels (levels 3 and 6). CI increased in all subjects under exercise conditions. Neither SV nor HR displayed significant differences between the three groups either at rest or under exercise conditions. Although HR increased continuously, no increase of indexed SV occurred beyond level 3. Noninvasive determination of CI at rest and during exercise with the IGR method is feasible in the pediatric age group. At medium-term follow-up, we found no significant differences between patients who underwent surgical or interventional ASD closure compared with normal controls.

Cardiopulmonary exercise function among patients undergoing transcatheter pulmonary valve implantation in the US Melody valve investigational trial

OBJECTIVES

We assessed the hypothesis that there is an improvement in clinical and physiologic parameters of cardiopulmonary exercise testing (CPET) after implantation of a transcatheter pulmonary valve (TPV).

BACKGROUND

Transcatheter pulmonary valve provides a new tool for treating conduit stenosis and regurgitation in patients with right ventricle (RV) to pulmonary artery conduit dysfunction.

METHODS

Patients who underwent a TPV placement between January 2007 and January 2010 (N = 150) were investigated with a standardized CPET protocol before and at 6 months after TPV placement. Cardiopulmonary exercise testing was performed on a mechanically braked cycle ergometer with respiratory gas exchange analysis.

RESULTS

Six months post TPV, small but statistically significant improvements were observed in the maximum workload (65.0% ± 18.8% to 68.3% ± 20.3% predicted, P < .001) and the ratio of minute ventilation to CO(2) production at the anaerobic threshold (30.8 ± 4.7 to 29.1 ± 4.1, P < .001). There was no significant change in peak oxygen consumption (VO(2)). Patients with pre-TPV hemodynamics consistent with RV dysfunction and patients with a lower pre-TPV peak VO(2) tended to have the greatest improvement in peak VO(2). The correlation between TPV-related improvements in peak VO(2) and baseline clinical variables were weak, however, and these variables could not be used to reliably identify patients likely to have improved peak VO(2) after TPV.

CONCLUSION

In patients with RV to pulmonary artery conduit dysfunction, TPV is associated with modest improvement in exercise capacity and gas exchange efficiency during exercise.

Canadian Cardiovascular Society 2009 Consensus Conference on the management of adults with congenital heart disease: shunt lesions

With advances in pediatric cardiology and cardiac surgery, the population of adults with congenital heart disease (CHD) has increased. In the current era, there are more adults with CHD than children. This population has many unique issues and needs. Since the 2001 Canadian Cardiovascular Society Consensus Conference report on the management of adults with congenital heart disease, there have been significant advances in the field of adult CHD. Therefore, new clinical guidelines have been written by Canadian adult CHD physicians in collaboration with an international panel of experts in the field. Part I of the guidelines includes recommendations for the care of patients with atrial septal defects, ventricular septal defects, atrioventricular septal defects and patent ductus arteriosus. Topics addressed include genetics, clinical outcomes, recommended diagnostic workup, surgical and interventional options, treatment of arrhythmias, assessment of pregnancy risk, and follow-up requirements. The complete document consists of four manuscripts, which are published online in the present issue of The Canadian Journal of Cardiology. The complete document and references can also be found at www.ccs.ca or www.cachnet.org.

Percutaneous closure of atrial septal defects: echocardiographic and functional results in patients older than 60 years

BACKGROUND

Percutaneous closure of atrial septal defects is well established in children and adults and has been found to improve symptoms and positively influence right-heart remodeling. The aim of this study was to evaluate the efficacy and long-term outcome in adult patients older than 60 years.

METHODS AND RESULTS

The study population comprised 96 patients in the age group of 60 to 84 years. Percutaneous closure was performed effectively in all patients. Functional capacity according to New York Heart Association functional class and peak oxygen uptake (VO(2)max) in the cardiopulmonary exercise testing improved significantly after atrial septal defects closure, especially in patients with a pulmonary-to-systemic flow ratio >2. Echocardiographic measurements of the right ventricular end-diastolic diameter showed a significant decrease. No device-associated complications were observed, but in 16 patients, paroxysmal atrial fibrillation occurred after device implantation.

CONCLUSIONS

Percutaneous atrial septal defects closure can be performed safely and with minimal risk even in elderly patients. They profit in terms of symptom reduction, improvement of exercise capacity, and right-heart remodeling.

Atrial septal defect: spectrum of care

Atrial septal defect (ASD) is a common congenital heart defect. Variability in management of this lesion exists among clinicians. A review of the literature reveals that there is lack of standard guidelines for the evaluation and management of patients with different types of ASDs. This survey-based study was conducted to test the uniformity of diagnostic and therapeutic approach to management of children with secundum, sinus venosus, and primum ASDs. Survey questionnaires were prepared to include questions regarding follow-up, diagnosis, and therapeutic intervention of different types and sizes of ASDs. Questions addressed follow-up visitations, type and frequency of investigative studies, pharmacological therapy, and choice of repair method. Surveys were sent out to all pediatric cardiology academic programs in the United States (n=48) and randomly selected international programs from Europe, Asia, and Australia (n=19). A total of 23 programs (34%) responded to the survey (15 from the United States and 8 internationally). A separate questionnaire was prepared for secundum, primum, and sinus venosus ASD. In each questionnaire, lesion types were subdivided into small, moderate, and large defect sizes to address differences of management approaches to each defect type and size. Results indicate that in secundum ASD, most participants use size of the defect and/or evidence of right-sided volume overload as criteria for defining small, moderate, and large defects. Frequency of follow-up does not vary with the type of lesion but is more frequent with larger defects. Most participants see patients with small defects at intervals of 6 months to 1 year and those with large defects at 3- to 6-month intervals. Age of patient and presence of symptoms determined the frequency of follow-up across all defects. Echocardiography was the most frequently used investigative modality in all defect sizes and types during follow-up visits (used by >80% for follow-up), followed by electrocardiography (ECG). There is a striking preference for the use of pharmacological therapy in primum ASD compared with secundum and sinus venosus ASD. The timing of repair was mainly dependent on patient age and symptomatology in different defects, with the presence of associated anomalies contributing to that in primum and sinus venosus ASD. Most participants use percutaneous approach to close secundum ASD (either as a first choice or as one of two choices depending on the presence of certain features). Before repair, participants use MRI or cardiac catheterization to fully evaluate a secundum ASD if it is large. These investigative modalities are not commonly used in primum and sinus venosus ASD. There is agreement on postoperative follow-up in different types of defects, with most participants continuing follow-up indefinitely, especially in larger defects.

Long-term cardio-respiratory consequences of heart disease in childhood

The dynamic interaction between the heart and lungs leads to a degree of respiratory co-morbidity including both restrictive and obstructive airway abnormalities, which may be overlooked in children with congenital and acquired heart disease. The improving imaging techniques of the heart, both foetal and post-natal coupled with minimally invasive techniques for device implantation and better operative techniques for complex congenital heart disease have resulted in more children with longitudinally documented structural heart disease surviving into their adult years. Children presenting with cardiomyopathy or arrhythmias, as well as those with repaired cardiac disease, can be offered advice with regard to formal exercise testing and participation in sports, which may be particularly helpful in the adolescent years. Furthermore, through the interest of some adult cardiologists in paediatric heart disease over the past 20 years, facilities for the smooth transition of care to adult services are improving.

Long-term impact of transcatheter atrial septal defect closure in adults on cardiac function and exercise capacity

BACKGROUND

The long-term impact of transcatheter atrial septal defect (ASD) closure on right ventricular (RV) remodeling and exercise capacity is unknown.

METHODS

We studied with cardiopulmonary exercise testing and transthoracic echocardiography 29 adults (age 42.3+/-16.4 years) with hemodynamically significant ASD just before transcatheter defect closure and after 6 and >36 months from closure.

RESULTS

Compared to 6 months after closure, a further improvement of peak oxygen uptake (p<0.001) and of the slope of ventilation/carbon dioxide production (p<0.001) was observed 3 years after the procedure, so that peak oxygen uptake appeared to be within the normal range in 23/29 patients (79%). Right ventricular short-axis (p<0.05) and long-axis (p<0.05) diameters further decreased beyond the 6-month period. The long-term improvement in exercise capacity correlated with pulmonary-to-systemic flow ratio (R=0.55, p=0.003) and with percentage decrease in RV short-axis diameter (R=0.59, p=0.002), but it did not correlate with age at closure (R=0.25, p=0.46). All patients who did not achieve a normal exercise capacity after 3 years from closure had a severely depressed pre-closure peak oxygen uptake (<50% of predicted).

CONCLUSIONS

Adults who undergo transcatheter ASD closure may experience a further improvement in exercise capacity in the long term. The long-term improvement in exercise capacity is associated to an improvement in cardiac form and function and is not influenced by age at closure. Even if the majority of patients may reach a normal exercise capacity after ASD closure, an abnormal exercise capacity may persist in those patients that had a peak oxygen uptake below 50% of predicted value before the procedure.

Evaluation of Exercise Capacity with Cardiopulmonary Exercise Testing and Type B Natriuretic Peptide Concentrations in Adult Patients with Patent Atrial Septal Defect

Adults with patent atrial septal defect (ASD) usually find their exercise capacity satisfactory, and therefore hesitate to accept proposed surgical treatment of the heart disease. The aim of our study was to evaluate both the exercise capacity, using the cardio-pulmonary stress test, and brain natriuretic peptide (BNP) levels in asymptomatic adults with ASD. Thirty-six patients with patent secundum type ASD (aged mean 44.7 +/- 8.2 years) were studied. The control group consisted of 25 healthy subjects at the mean age of 45.6 +/- 6.1 years. Echocardiography and CPST were performed and BNP levels measured in all subjects. Oxygen uptake (VO2 max) was lower in ASD patients than in controls (22.1 +/- 5.6 vs. 30.0 +/- 6.8 ml/kg/min, p = 0.00001); the VE/VO2 slope was elevated in ASD patients compared with healthy subjects (31.3 +/- 6.6 vs. 26.9 +/- 3.3, p = 0.001), and exceeded 34 in 5 patients. VO2 max showed a negative correlation with the pulmonary to systemic flow ratio Qp:Qs (r = -0.46, p = 0.004), and a positive correlation was found between the VE/VO2 slope and Qp:Qs (r = 0.32, p = 0.05). BNP levels were higher in the ASD group than in the controls (60.6 +/- 49.9 vs. 32.6 +/- 24.5 pg/ml, p = 0.02). BNP correlated positively with RV diameter and Qp:Qs (r = 0.38 and 0.39 respectively, p = 0.03) and negatively with maximum VO2 (r = -0.5, p = 0.004) and VO2% (r = -0.32, p = 0.07).

CONCLUSIONS

Although most adult patients with ASD perceive their exercise capacity as satisfactory, objective assessment reveals that in fact it is significantly decreased. BNP levels are increased comparing to healthy individuals. Decreased exercise capacity and increased BNP levels seem to result from right ventricular volume overload.

Impact of cardiac rehabilitation on the exercise function of children with serious congenital heart disease

OBJECTIVES

The exercise capacity of children with congenital heart disease (CHD) is often depressed. This depression is thought to be attributable to (1) residual hemodynamic defects and (2) deconditioning secondary to physical inactivity. We hypothesized that this latter component would be ameliorated by a formal cardiac rehabilitation program designed specifically for children. The objective of this study was to characterize the effect of a cardiac rehabilitation program on the exercise performance of children with CHD and to define the physiologic mechanisms that might account for any improvements that are observed.

METHODS

Nineteen patients with CHD who were referred for exercise testing and found to have a peak oxygen consumption (VO2) and/or peak work rate <80% of predicted were enrolled in the study. Sixteen patients (11 Fontan patients, 5 with other CHD) completed the program and had postrehabilitation exercise tests, results of which were compared with the prerehabilitation studies.

RESULTS

Improvements were found in 15 of 16 patients. Peak VO2 rose from 26.4 +/- 9.1 to 30.7 +/- 9.2 mL/kg per min; peak work rate from 93 +/- 32 to 106 +/- 34 W, and the ventilatory anaerobic threshold from 14.2 +/- 4.8 to 17.4 +/- 4.5 mL/kg per min. The peak heart rate and peak respiratory exchange ratio did not change, suggesting that the improvements were not attributable merely to an increased effort. In contrast, the peak oxygen pulse rose significantly, from 7.6 +/- 2.8 to 9.7 +/- 4.1 mL/beat, an improvement that can be attributed only to an increase in stroke volume and/or oxygen extraction at peak exercise. No patient experienced rehabilitation-related complications.

CONCLUSION

Cardiac rehabilitation can improve the exercise performance of children with CHD. This improvement is mediated by an increase in stroke volume and/or oxygen extraction during exercise. Routine use of formal cardiac rehabilitation may greatly reduce the morbidity of complex CHD.

Transcatheter closure of atrial septal defects improves right ventricular volume, mass, function, pulmonary pressure, and functional class: a magnetic resonance imaging study

OBJECTIVE

To characterise prospectively by magnetic resonance imaging (MRI) changes in right ventricular (RV) volume, function, and mass after transcatheter closure of atrial septal defects (ASDs) and to evaluate the course of pulmonary pressure and functional class criteria.

METHODS

In 20 patients with secundum-type ASD and dilated RV diameter, MRI was performed to quantify RV end diastolic (RVEDV) and end systolic volumes (RVESV), RV mass, tricuspid annular diameter, and RV ejection fraction before and 6 and 12 months after transcatheter closure of the ASD. RV systolic pressure was measured during follow up by transthoracic echocardiography.

RESULTS

Functional class improved in the majority of patients after ASD closure. RVESV (from 81 (18) ml/m2 to 53 (15) ml/m2, p < 0.001), RVEDV (from 127 (17) ml/m2 to 99 (18) ml/m2, p < 0.001), and RV mass (from 79 (10) g to 63 (8) g, p < 0.01) decreased significantly during follow up, although tricuspid annular diameter did not. RV ejection fraction improved (by 9% compared with baseline, p < 0.05) and RV systolic pressure decreased significantly (from 33 (8) mm Hg to 24 (6) mm Hg, p < 0.001) after closure.

CONCLUSION

MRI studies showed significant improvement of RV volumes, mass, and function after transcatheter closure of ASDs. Restoration of the RV leads to decreased pulmonary pressure resulting in a better functional class in the majority of patients.

Sinus Venosus Atrial Septal Defect

Background— Sinus venosus atrial septal defect (SVASD) differs from secundum atrial septal defect by its atrial septal location and its association with anomalous pulmonary venous connection (APVC). Data on long-term outcome after surgical repair are limited.

Methods and Results— We reviewed outcomes of 115 patients (mean age±SD 34±23 years) with SVASD who had repair from 1972 through 1996. APVC was present in 112 patients (97%). Early mortality was 0.9%. Complete follow-up was obtained for 108 patients (95%) at 144±99 months. Symptomatic improvement was noted in 83 patients (77%), and deterioration was noted in 17 patients (16%). At follow-up, 7 (6%) of 108 patients had sinus node dysfunction, a permanent pacemaker, or both, and 15 (14%) of 108 patients had atrial fibrillation. Older age at repair was predictive of postoperative atrial fibrillation ( P =0.033). No reoperations were required during follow-up. Survival was not different from expected for an age- and sex-matched population. Clinical improvement was more common with older age at surgery ( P =0.014). Older age at repair ( P =0.008) and preoperative New York Heart Association class III or IV ( P =0.038) were independent predictors of late mortality.

Conclusions— Operation for SVASD is associated with low morbidity and mortality, and postoperative subjective clinical improvement occurs irrespective of age at surgery. Postoperative atrial fibrillation appears to be related to older age at operation. SVASD repair achieves survival similar to that of a matched population and should be considered whenever repair may impact survival or symptoms.

Comparison of strain rate imaging for quantitative evaluation of regional left and right ventricular function after surgical versus percutaneous closure of atrial septal defect

For the first time, peak systolic strain and strain rate (SR) were used to assess right ventricular (RV) and left ventricular (LV) regional function in children after transcatheter and surgical atrial septal defect (ASD) closure. Fifteen patients with successful ASD device closure (the ASD-D group, mean age 9 +/- 3 years), 15 age- and gender-matched patients with successful ASD surgical closure (the ASD-S group, mean age 9 +/- 3 years), and 15 age- and gender-matched controls were enrolled. Regional RV and LV longitudinal function was significantly reduced in the ASD-S group compared with controls in all the studied segments. The ASD-D group presented significantly (p <0.001) reduced strain and SR values only on the basal and mid segments of the septal wall compared with controls. In the ASD-D group, only the RV basal segment showed significantly (p <0.001) reduced strain and SR values compared with controls but significantly greater values than those measured in the ASD-S group. SR imaging indexes could provide new, noninvasive, clinically relevant insight into regional changes in RV function and support the transcatheter approach to ASD for its less negative impact on RV and LV function.

Late outcomes in patients with surgically treated congenital heart disease

Optimizing late outcomes should be the end result of improvements in medical and surgical care for congenital heart disease (CHD). In addition to mortality, significant morbidities after surgery for CHD need to be considered. These include the need for reintervention, cardiovascular complications, exercise limitations, neurocognitive morbidities, effects on pregnancy, difficulty obtaining insurance, need for chronic medications, and impaired functional status and quality of life. Long-term outcome studies are difficult to perform, and their interpretation is complicated by intervening changes in management. Specific discussion of long-term follow-up of tetralogy of Fallot, D-transposition of the great arteries, and hypoplastic left heart syndrome illustrates the myriad management changes over the last three decades, the challenges in predicting outcomes for recent patients, and the need for ongoing initiation of long-term follow-up studies.

Three-dimensional color Doppler echocardiography for assessing shunt volume in atrial septal defects

Background Three-dimensional color Doppler echocardiography has been used to assess cardiac blood flow in experimental settings. We tested whether this technique can be applied to assess transatrial shunt flow in patients with atrial septal defect in a clinical setting. Methods In 46 consecutive patients with atrial septal defects, shunt flow was assessed during cardiac catheterization using the Fick method and by conventional 2-D quantitative transesophageal Doppler echocardiography. The averaged values for shunt flow obtained by both methods were used as a reference. Transesophageal 3-D color Doppler echocardiography was performed for analysis of the 3-D flow velocity field of transatrial shunt flow. Shunt volume was calculated by application of the Gauss theorem. Results We found a close correlation between shunt volume (L/min) obtained by either 3-D color Doppler echocardiography or the reference methods ( r = 0.981, P < .001). Using 3-D color Doppler data to predict the reference values, 95% confidence limits were -11.5 to +11.6%. Conclusions Shunt flow in patients with atrial septal defects can be assessed in a clinical setting by transesophageal 3-D color Doppler echocardiography.

Symptomatic atrial arrhythmias and transcatheter closure of atrial septal defects in adult patients

OBJECTIVE

To determine whether transcatheter device closure of a secundum atrial septal defect (ASD) will reduce the risk of developing subsequent atrial arrhythmias.

DESIGN

The incidence and predictors of symptomatic atrial tachyarrhythmias (AT) were examined in adults undergoing transcatheter closure of ASDs.

SETTING

Toronto Congenital Cardiac Centre for Adults.

PATIENTS

132 consecutive patients, mean (SD) age 44 (16) years; 74% female.

MAIN OUTCOME MEASURE

Sustained or symptomatic atrial arrhythmias at early follow up (six weeks; n = 115) and intermediate follow up (last clinic visit 17 (11) months post surgery; n = 121).

RESULTS

15% of the patients (20 of 132) had AT before the procedure (14 paroxysmal, six persistent). Patients without a history of arrhythmia had a low incidence of AT during early follow up (6%) and intermediate follow up (1%/year), while all patients with persistent AT before closure remained in atrial fibrillation or flutter. Of patients in sinus rhythm but with a previous history of AT, two thirds remained arrhythmia-free at follow up, with overall incidences of paroxysmal and persistent AT of 17%/year and 11%/year. A history of AT before closure (risk ratio (RR) 35.0, 95% confidence interval (CI) 7.2 to 169.0) and age > or = 55 years at the time of device insertion (RR 5.6, 95% CI 1.2 to 25.0) predicted AT after closure.

CONCLUSIONS

Device closure of an ASD before the onset of atrial arrhythmias may protect against the subsequent development of arrhythmia, in particular in patients less than 55 years of age.

[Percutaneous closure of the inter-auricular communications, well defined indications]

POSSIBLITIES FOR PROGNOSTIC IMPROVEMENT: The inter-auricular communication (IAC) is the most frequent of congential malformations in adults and is responsible for enhanced morbidity and rduction in life expectancy. The closure of an IAC with volumic overload eradicates such morbidity and mortality. The technical progress in the conception of prosthesises that obstrue the interauricular communications via the percutaneous route make this technique a reliable alternative to surgery that, itself, leads to a certain degree of discomfort and considerable morbidity. DEPENDING ON THE ECHOCARDIOGRAPHICAL DATA: The selection of patients is crucial and relies on trans-thoracic echocardiography. It is indicated in isolated ostium secundum-type inter-auricular communications with a border of at least 4 mm separating it from the adjacent structures of the heart; the size on the echocardiography must not exceed 30 mm. FROM A TECHNICAL POINT OF VIEW: The closure is made under fluoroscopic and echocardiographic control via the trans-oesophageal route. It is rapid, simple, and induces a low rate of morbidity. With Amplatz's prosthesis, the percentage of complete closure is equivalent to that obtained with surgery but with less morbidity with regard to arrhythmia. Today the reliable percutaneous closure of an IAC will probably permit the extension of the indications for the closure of this congenital abnormality in adults.

Determinants of cardiopulmonary functional improvement after transcatheter atrial septal defect closure in asymptomatic adults

OBJECTIVES

We sought to evaluate the course of cardiopulmonary function after transcatheter atrial septal defect (ASD) closure and to identify the physiopathologic mechanisms leading to this change.

BACKGROUND

Conflicting reports exist on cardiopulmonary functional improvement in asymptomatic adults after transcatheter closure of a secundum ASD.

METHODS

Thirty-two consecutive adults (13 males; age 42.6 +/- 16.7 years) underwent maximal cardiopulmonary exercise testing and transthoracic echocardiography both on the day before and six months after transcatheter ASD closure. Mean pulmonary artery pressure, pulmonary to systemic flow ratio (Qp/Qs), and ASD diameter were measured before closure.

RESULTS

Peak oxygen uptake (Vo(2)) (p < 0.001), peak oxygen pulse (p = 0.0027), and vital capacity (p = 0.0086) improved after ASD closure, although peak heart rate did not. A significant correlation was found between peak Vo(2) improvements and Qp/Qs (p = 0.0013). Left ventricular ejection fraction (LVEF) (p < 0.0001) and left ventricular end-diastolic diameter (LVEDD) (p < 0.0001) significantly increased after six months, although left ventricular end-systolic diameter did not. Right ventricular long- and short-axis dimensions decreased (both p < 0.0001). Peak Vo(2) and of peak oxygen pulse improvements correlated to both LVEF (p = 0.0009 and 0.0019, respectively) and LVEDD (p < 0.0001 and 0.032, respectively) increments. The decrease of both long- and short-axis right ventricular dimensions positively correlated to both LVEF and LVEDD improvements. The improvement in LVEF correlated to Qp/Qs (p = 0.0026).

CONCLUSIONS

Transcatheter ASD closure leads to a significant improvement in cardiopulmonary function within six months, via an increase in peak oxygen pulse. An increase in both left ventricular stroke volume and cardiac output due to a positive ventricular interaction is the mechanism leading to improved peak Vo(2).

Clinical update on adults with congenital heart disease

The number of patients with congenital cardiac disease reaching adulthood is increasing steadily. Many adults with such disease face both medical and surgical difficulties. Most clinicians know very little about basic cardiac defects, their natural history, complications after surgery, and adequate management of these patients. We aim to provide an overview of the most frequently encountered cardiac lesions and long-term complications and to outline an up-to-date approach to their management. We present a series of hypothetical cases and discuss their management.

Improvement in exercise capacity in asymptomatic and mildly symptomatic adults after atrial septal defect percutaneous closure

BACKGROUND

Controversy exists as to whether secundum atrial septal defects (ASDs) in asymptomatic or mildly symptomatic New York Heart Association (NYHA) class I or II adult patients should be closed.

METHODS AND RESULTS

Thirty-seven patients (24 females; mean age 49.4 years, range 19 to 76) with a mean pulmonary to systemic flow ratio (Qp:Qs) of 2.1 (1.2 to 3.4) had a maximal oxygen uptake (VO2max) determination and echocardiographic measurement of right ventricular dimensions before and 6 months after elective percutaneous closure of ASD. At baseline, mean VO2max was 23.5+/-6.4 mL/kg per minute and was higher in the 15 NYHA I patients than in the 22 NYHA II patients (27+/-6.9 versus 20.8+/-4.6 mL/kg per minute; P=0.0015). VO2max increased significantly at 6 months (23.5+/-6.4 to 26.9+/-6.9 mL/kg per minute; P<0.0001). Improvement was as marked in NYHA I (+22%; P<0.0001) as in NYHA II patients (+12%; P<0.0001), in patients with Qp:Qs 1.2 to 2.0 (+16%; P<0.0001) as in those with Qp:Qs >2 (+12%; P<0.0001), and in patients > or =40 years of age (+14%; P<0.0001) as in those <40 years of age (+16%; P<0.0001). Compared with 15 of 37 patients before closure, 35 of 37 patients were in NYHA I at 6 months. Right ventricular dimensions decreased significantly (P<0.0001).

CONCLUSIONS

Adult ASD patients significantly increase their functional capacity after percutaneous defect closure. This is observed even in patients classified as asymptomatic, in those with lesser shunts, and in older patients. These findings suggest that ASD closure in an adult population should be considered even in the absence of symptoms.

Percutaneous closure with Amplatzer device is a safe and efficient alternative to surgery in adults with large atrial septal defects

BACKGROUND

In adults with atrial septal defect (ASD) and large right-to-left shunt, closure of the defect is recommended. Percutaneous closure is still rarely used in this population. This study presents the results of transcatheter closure with the Amplatzer occluder in such patients.

METHODS AND RESULTS

We studied 44 consecutive adult patients with a secundum ASD and 2 of the 3 following criteria: QP/QS >/=2 by oximetry, echocardiographic right ventricle overload, and ASD size >20 mm. Forty-two patients had a successful implantation. In 1 patient an unstable device was withdrawn; in another one, the device embolized in the pulmonary artery. At 6-month median follow-up, 95% had a complete closure; 2 patients with an additional defect had a small residual shunt. Major complications were the aforementioned embolization and a cerebrovascular accident in a patient with atrial fibrillation treated with aspirin. Others were minor and transitory: premature atrial beats in 3 patients, and paroxysmal atrial fibrillation and pulmonary edema in 1 patient each.

CONCLUSIONS

Transcatheter closure of large ASDs with the Amplatzer device is efficient with less morbidity than surgical closure.