Exercise Capacity Long-Term after Arterial Switch Operation for Transposition of the Great Arteries

Decreased cardiac reserve in asymptomatic patients after arterial switch operation for transposition of the great arteries

BACKGROUND

Exercise capacity is impaired in patients after arterial switch operation (ASO) for complete transposition of the great arteries. Maximal oxygen consumption is related with outcome.

OBJECTIVES

This study assessed ventricular function by advanced echocardiography and cardiac magnetic resonance (CMR) imaging at rest and during exercise, to determine exercise capacity in ASO patients, and to correlate exercise capacity with ventricular function as potential early marker of subclinical impairment.

METHODS

Forty-four patients (71% male, mean age 25 ± 4 years - range 18-40 years) were included during routine clinical follow-up. Assessment involved physical examination, 12‑lead ECG, echocardiography, and cardiopulmonary exercise test (CPET) (day 1). On day 2 CMR imaging at rest and during exercise was performed. Blood was sampled for biomarkers.

RESULTS

All patients reported New York Heart Association class I, the overall cohort had an impaired exercise capacity (80 ± 14% of predicted peak oxygen consumption). Fragmented QRS was present in 27%. Exercise CMR showed that 20% of patients had abnormal contractile reserve (CR) of the left ventricle (LV) and 25% had reduced CR of the right ventricle (RV). CR LV and CR RV were significantly associated with impaired exercise capacity. Pathological patterns on myocardial delayed enhancement and hinge point fibrosis were detected. Biomarkers were normal.

CONCLUSION

This study found that in some asymptomatic ASO patients electrical, LV and RV changes at rest, and signs of fibrosis are present. Maximal exercise capacity is impaired and seems to be linearly related to the CR of the LV and the RV. Therefore, exercise CMR might play a role in detecting subclinical deterioration of ASO patients.

Exercise Capacity After Arterial Switch Operation in Patients with D-Transposition of Great Arteries: Does the Coronary Artery Anatomy Matter?

Variant coronary anatomy (VarCA) is frequent in D-Transposition of the great arteries (d-TGA). There are a paucity of data on the effect of the VarCA on the exercise capacity (XC) in patients with repaired d-TGA. This retrospective study included patients with d-TGA who underwent an arterial switch operation (ASO) and had at least one cardiopulmonary exercise test (CPET). Data from the treadmill CPET and simultaneously performed spirometry were collected. The parameters of CPET were compared between patients with usual anatomy vs. VarCA. Longitudinal changes in XC in patients with ASO were also analyzed. A total of 44 patients with either usual coronary anatomy (n = 27, 61%) or VarCA (n = 17, 39%) met inclusion criteria. There was no significant difference in oxygen consumption (%VO₂) at initial CPET (104 vs. 100%, p = 0.53) between the two groups. Abnormal %VO₂ (< 85%) was uncommon in both groups (n = 2, 7.4% vs. n = 4; 23.5%; p = ns). For longitudinal changes, there was no significant decline in %VO₂ in either group: (i) usual coronary anatomy (n = 15, median follow-up 4.8 years, %VO₂ 111 vs. 108%; p = 0.306) and (ii) VarCA (n = 10, median follow-up 6.6 years, %VO₂ 106 vs. 92%; p = 0.441). Spirometry was abnormal in 25 (59.5%) patients [restrictive (n = 8, 19.0%), obstructive (n = 15, 35.7%), and mixed (n = 2, 4.8%)] butabnormal spirometry had no impact on the XC. Patients with d-TGA who underwent neonatal ASO uniformly exhibited good XC without any longitudinal decline on medium-term follow-up, regardless of coronary artery anatomy. Although frequent (60%), abnormal spirometry was not associated with reduced exercise capacity.

Guidelines for physical activity in children with heart disease

Justification

In recent years, there has been increasing recognition of children with heart disease in our country. These children belong to different age groups and have untreated, partially treated, or completely treated heart disease. The role of physical activity for optimal physical, emotional, and psychosocial well-being for children is well understood. There is a challenge for the parents and the medical professionals to take a decision regarding the type of physical activity safe for the child as heart disease may affect the hemodynamic demands. Most of the existing international guidelines focus on competitive sports in operated heart disease children. This may be of limited use when we have a mixed population of children with heart disease, different types of sports in our country and where a larger subset is looking for recommendations to leisure time activities.

Process

The Pediatric Cardiac Society of India decided to formulate recommendations for physical activity in children with heart diseases. A committee of experts, who were well-versed with the subject of physical activity in children with heart disease, volunteered to take up the task of writing the guidelines. The recommendations emerged following deliberations of the committee members, on the virtual platform as well as mails. The final version of manuscript was approved by all committee members and all members are co-authors of this manuscript. The different types of physical activities were defined including leisure sports and competitive sports. The exercise was classified based on the mechanical action of muscles involved into dynamic and static components. Each type of exercise was then classified based on the intensity into low, medium, and high. Recommendations for the type of physical activity for individual heart lesions were decided based on the rationale available.

Objectives

The recommendations here are made with an intention to provide general guidelines for physical activity in children with operated and unoperated heart diseases, not excluding a need for individualizing a plan, serial assessment, and comprehensive checkup in special situations.

Recommendations

We hope the recommendations mentioned below would provide basic clarity in planning physical activity in children with heart disease. This is with the hope to encourage physically active life, at the same time ensuring a safety net.

Exercise Capacity in Children and Adolescents With Congenital Heart Disease: A Systematic Review and Meta-Analysis

Background

Congenital heart disease (CHD) entails structural defects in the morphogenesis of the heart or its main vessels. Analyzing exercise capacity of children and adolescents with CHD is important to improve their functional condition and quality of life, since it can allow timely intervention on poor prognostic factors associated with higher risk of morbidity and mortality.

Objective

To describe exercise capacity in children and adolescents with CHD compared with healthy controls.

Methods

A systematic review was carried out. Randomized clinical trials and observational studies were included assessing exercise capacity through direct and indirect methods in children and adolescents between 5 and 17 years-old. A sensitive analysis was performed including studies with CHD repaired participants. Additionally, it was sub-analyzed by age range (< and ≥ 12 years old). Two independent reviewers analyzed the studies, extracted the data, and assessed the quality of the evidence.

Results

5619 articles were found and 21 were considered for the review. Eighteen articles used the direct exercise capacity measurement method by cardiopulmonary exercise test (CPET). The CHD group showed significant differences in peak oxygen consumption (VO₂peak) with a value of −7.9 ml/Kg/min (95% CI: −9.9, −5.9, p = 0.00001), maximum workload (Wmax) −41.5 (95% CI: −57.9, −25.1 watts, p = 0.00001), ventilatory equivalent (VE/VCO₂) slope 2.6 (95% CI: 0.3, 4.8), oxygen pulse (O₂ pulse)−2.4 ml/beat (95% CI: −3.7, −1.1, p = 0.0003), and maximum heart rate (HRmax) −15 bpm (95% CI: −18, −12 bpm, p = 0.00001), compared with healthy controls. Adolescents (≥ 12 yrs) with CHD had a greater reduction in VO₂peak (−10.0 ml/Kg/min (95% CI: −12.0, −5.3), p < 0.00001), Wmax (−45.5 watts (95% CI: −54.4, −36.7), p < 0.00001) and HRmax (−21 bpm (95% CI: −28, −14), p<0.00001).

Conclusion

Suffering CHD in childhood and adolescence is associated with lower exercise capacity as shown by worse VO₂peak, Wmax, VE/VCO₂ slope, O₂ pulse, and HRmax compared with matched healthy controls. The reduction in exercise capacity was greater in adolescents.

Systematic Review Registration

www.crd.york.ac.uk/prospero/display_record.php?RecordID=208963, identifier: CRD42020208963.

Oxygen Uptake Efficiency Slope is Strongly Correlated to VO2peak Long-Term After Arterial Switch Operation

After the arterial switch operation (ASO) for transposition of the great arteries (TGA), many patients have an impaired exercise tolerance. Exercise tolerance is determined with cardiopulmonary exercise testing by peak oxygen uptake (VO_2peak). Unlike VO_2peak, the oxygen uptake efficiency slope (OUES) does not require a maximal effort for interpretation. The value of OUES has not been assessed in a large group of patients after ASO. The purpose of this study was to determine OUES and VO_2peak, evaluate its interrelationship and assess whether exercise tolerance is related to ventricular function after ASO. A cardiopulmonary exercise testing, assessment of physical activity score and transthoracic echocardiography (fractional shortening and left/right ventricular global longitudinal peak strain) were performed to 48 patients after ASO. Median age at follow-up after ASO was 16.0 (IQR 13.0-18.0) years. Shortening fraction was normal (36 ± 6%). Left and right global longitudinal peak strain were reduced: 15.1 ± 2.4% and 19.5 ± 4.5%. This group of patients showed lower values for all cardiopulmonary exercise testing parameters compared to the reference values: mean VO_2peak% 75% (95% CI 72-77) and mean OUES% 82(95% CI 77-87); without significant differences between subtypes of TGA. A strong-to-excellent correlation between the VO_2peak and OUES was found (absolute values: R = 0.90, p < 0.001; normalized values: R = 0.79, p < 0.001). No correlation was found between cardiopulmonary exercise testing results and left ventricle function parameters. In conclusion, OUES and VO_2peak were lower in patients after ASO compared to reference values but are strongly correlated, making OUES a valuable tool to use in this patient group when maximal effort is not achievable.

Abnormal Pulmonary Artery Bending Correlates With Increased Right Ventricular Afterload Following the Arterial Switch Operation

PURPOSE

In transposition of great arteries, increased right ventricular (RV) afterload is observed following arterial switch operation (ASO), which is not always related to pulmonary artery (PA) stenosis. We hypothesize that abnormal PA bending from the Lecompte maneuver may affect RV afterload in the absence of stenosis. Thus, we sought to identify novel measurements of three-dimensional cardiac magnetic resonance (CMR) images of the pulmonary arteries and compare with conventional measurements in their ability to predict RV afterload.

METHODS

Conventional measurements and novel measurements of the pulmonary arteries were performed using CMR data from 42 ASO patients and 13 age-matched controls. Novel measurements included bending angle, normalized radius of curvature (R_c), and normalized weighted radius of curvature (R_c-w). Right ventricular systolic pressures (as the surrogate for RV afterload) were measured by either recent echocardiogram or cardiac catheterization.

RESULTS

Conventional measurements of proximal PA size correlated with differential pulmonary blood flow (r = 0.49, P = .001), but not with RV peak systolic pressures (r = -0.26, P = .18). In ASO patients, R_c-w correlated with higher RV systolic pressures (r = -0.57, P = .002). Larger neoaortic areas and rightward bending angles correlated with smaller right pulmonary artery R_c (r = -0.48, P = .001; r = 0.41, P = .01, respectively). Finally, both pulmonary arteries had significantly smaller R_c compared to normal controls.

CONCLUSIONS

Pulmonary arteries exhibit abnormal bends following ASO that correlate with increased RV afterload, independent of PA stenosis. Future work should focus on clinical and hemodynamic contributions of these shape parameters.

Impact of congenital heart surgery on quality of life in children and adolescents with surgically corrected Ventricular Septal Defect, Tetralogy of Fallot, and Transposition of the Great Arteries

OBJECTIVE

To describe the impact of CHD surgery in early childhood on quality of life in children aged 10-16 years with surgically corrected Ventricular Septal Defect, Transposition of the Great Arteries, and Tetralogy of Fallot.

METHOD

A cross-sectional survey study of quality of life survey on 161 children and adolescents aged 10-16 years with surgically corrected Ventricular Septal Defect, Transposition of the Great Arteries, and Tetralogy of Fallot. The international Paediatric Quality of Life 4.0 quality of life questionnaires were applied and collected for assessment from patients and parents. The endpoints were total, physical, emotional, social, and school quality of life scores.

RESULTS

The quality of life total and school scores was significantly lower in children with CHD than their healthy peers. There was no significant difference in quality of life between the three CHD groups. All three CHD groups had a significantly lower total (7.7-13.2%, p<0.001) and school scores (21.1-31.6%, p<0.001) than the control group. The tetralogy of Fallot group was the only group that had significantly lower scores in the physical subscale (p<0.001) than the controls.

CONCLUSION

Children and adolescents with surgically corrected CHD show losses in quality of life in total and school scores compared to healthy controls. The tetralogy of Fallot group was the only CHD group that had significantly lower physical score than the controls.

Pregnancy outcomes and mid-term prognosis in women after arterial switch operation for dextro-transposition of the great arteries - Tertiary hospital experiences and review of literature

OBJECTIVE

Arterial switch operation (ASO) for dextro-transposition of the great arteries (d-TGA) has gradually replaced the atrial switch operation and has become the standard operation. To date, the outcomes of pregnant women with d-TGA after this new operation have not been investigated. In this study, we investigated the impact of ASO on pregnant outcomes and mid-term prognosis in women with d-TGA and compared with the atrial switch operation through the literature review.

METHODS AND RESULTS

There were 20 pregnancies in 10 women with d-TGA after ASO and 6 resulted in abortion. Among 14 successful pregnancies in 10 women, 11 pregnancies achieved the term delivery and 3 pregnancies, including 1 twin pregnancy, resulted in preterm labor. Maternal cardiovascular events occurred in 4 (heart failure and arrhythmias in 3 and arrhythmia in 1), and all were controllable with medications. Risk factors for the peripartum cardiac events were older age at ASO and delivery, and higher concentration of brain natriuretic peptide (BNP) at first trimester (p<0.05). In 7-60 month-follow-up after delivery, no case showed deterioration of functional class and systemic ventricular function. According to the literature review, women after ASO demonstrated a better prognosis than those after the atrial switch operation.

CONCLUSIONS

The majority of women with d-TGA after ASO tolerated pregnancy and delivery well. The older age at ASO, an elderly pregnancy, and higher BNP levels at the first trimester were possibly risk factors of peripartum cardiovascular events among the group. The literature reviews and this study may indicate the advantage of systemic left ventricle compared with systemic right ventricle in long-term outcomes after delivery.

Long-term Outcomes of the Arterial Switch Operation for d-Transposition of the Great Arteries

Dextrotransposition of the great arteries (d-TGA) is a relatively rare form of complex childhood congenital heart disease, which occurs in approximately 0.2 in 1000 live births (Long et al, 2010). The most common palliative procedure for this anatomy has become the arterial switch operation (ASO). We will review in this paper the evidence that is currently available regarding the clinical management following the ASO. Individuals with d-TGA who undergo ASO at a young age thus far have excellent long-term outcomes. Long-term complications for the ASO should be monitored for and patients should have routine follow-up with specialists in adult congenital heart disease.

Long-term Management of the Arterial Switch Patient

PURPOSE OF REVIEW

This review paper describes the management of patients with dextro-transposition of the great arteries (D-TGA) with a focus on the complications seen and the appropriate care required to identify and prevent adverse events.

RECENT FINDINGS

D-TGA is a form of cyanotic congenital heart disease (CHD) representing ~ 3% of all CHD and almost 20% of all cyanotic CHD. Since the late 1980s, standard of care is to repair these patients with an arterial switch operation (ASO) as opposed to a Mustard/Senning operation. The long-term survival and complication rates are superior in the ASO. Long-term follow-up is recommended for all D-TGA patients and includes management with adult congenital heart disease specialists and the use of echocardiography and advanced imaging with CT or MRI. The most common complications seen are pulmonary stenosis, coronary artery stenosis, and neo-aortic regurgitation. Careful evaluation of new symptoms or declining function is essential in preventing and treating these long-term sequelae.