Small unrepaired atrial septal defects display impaired exercise capacity compared with healthy peers
Sebastian Udholm1, Christian Rex1, Filip Eckerström1
1Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Aarhus, Denmark.
Objective:
Adult patients with small, unrepaired atrial septal defects have an increased risk of pneumonia, atrial fibrillation, and stroke. Furthermore, they have higher late mortality than the background population. The functional capacity is unknown in these patients. Therefore, our objective was to determine exercise capacity in adult patients diagnosed with an unrepaired atrial septal defect compared to healthy controls.
Design:
A cross-sectional study.
Patients:
Adult patients with small, unrepaired atrial septal defects, aged 18-65, diagnosed between 1953 and 2011.
Interventions:
Cardiopulmonary exercise test was performed using an incremental bicycle test and gas exchange was measured using breath-by-breath technique.
Outcome Measures:
Primary outcome was peak oxygen uptake, secondary outcome was maximal workload and ventilatory anaerobic threshold.
Results:
We included 32 patients previously diagnosed with a small, unrepaired atrial septal defect and 16 healthy, age- and gender-matched controls (age 36.3 ± 13 years). Patients were divided into two groups based on whether the atrial septal defect was open (age 36.3 ± 11 years) or spontaneously closed (age 36.8 ± 14 years) since time of diagnosis. No differences in demographic characteristics or weekly exercise levels were found. Both patient groups reached lower peak oxygen uptake (open: 31.7 ± 11 mL/kg/min; spontaneously closed: 29.7 ± 6.9 mL/kg/min) compared with controls (42.6 ± 6.1 mL/kg/min; P = .0001). Workload (open: 2.6 ± 1.0 watt/kg; spontaneously closed: 2.5 ± 0.6 watt/kg) and aerobic capacity (open: 21.4 ± 8.7 mL/kg/min; spontaneously closed: 22.5 ± 6.5 mL/kg/min) was also poorer in patients compared to controls (workload: 3.5 ± 0.5 watt/kg; P = .0006, aerobic capacity: 31.3 ± 6.8 mL/kg/min; P = .0007).
Conclusion:
Adult patients with a diagnosis of small, unrepaired atrial septal defect have significantly impaired exercise capacity when compared to healthy controls. The impairment was present even if, by the time of assessment, the defect had closed spontaneously. The pathophysiological mechanisms behind the impaired exercise capacity demonstrated in these patients remain unexplained and will be a target for future work.
Related Concept Videos
Lung Capacity
Influence of Parents and Peers on Identity
Parental Influence on Identity Development
Parents serve as primary guides and managers in an adolescent's life, offering support instrumental in decision-making and personal growth....
Lumber Defects
Shakes are minor fractures that run along or across the wood's annual rings, while wane is...
Respiratory Capacities
One key metric is the Inspiratory Capacity (IC), which represents the maximum amount of air that can be inhaled with full effort. IC is calculated by summing the tidal volume and inspiratory reserve volume, typically ranging from 2.4 to 3.6 liters.
The Functional Residual Capacity (FRC) represents the air in the...
Exercise Stress Test
Exercise stress testing, commonly known as a treadmill test, is a noninvasive procedure used to evaluate cardiovascular function and diagnose heart conditions.
Definition
An exercise stress test measures the heart's response to exertion using a treadmill or stationary bicycle. Chest electrodes record the heart's electrical activity through an ECG, and blood pressure is monitored regularly.
Purposes
Exercise and Muscle Performance
Endurance exercises
Endurance exercises involve running, swimming, or cycling, which require repetitive movements with low force output. When a person engages in endurance exercise, a few noticeable changes occur in their skeletal muscles. For instance, the number of capillaries...


