TY  - EJOU
AU  - Udholm, Sebastian 
AU  - Rex, Christian 
AU  - Eckerström, Filip 
AU  - Onat, Mine 
AU  - Nyboe, Camilla 
AU  - Hjortdal, Vibeke E. 

TI  - Small unrepaired atrial septal defects display impaired exercise capacity compared with healthy peers
T2  - Structural and Congenital Heart Disease

PY  - 2019
VL  - 14
IS  - 3
SN  - 3071-1738

AB  - Objective: Adult patients with small, unrepaired atrial septal defects have an in‐
creased risk of pneumonia, atrial fibrillation, and stroke. Furthermore, they have 
higher late mortality than the background population. The functional capacity is un‐
known 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, di‐
agnosed 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 ca‐
pacity demonstrated in these patients remain unexplained and will be a target for 
future work.
KW  - cardiopulmonary exercise test
KW  -  exercise capacity
KW  -  grown‐up with congenital heart disease (GUCH)
KW  -  simple lesions
KW  -  small atrial septal defect

DO  - 10.1111/chd.12740