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Habitual exercise correlates with exercise performance in patients with conotruncal abnormalities.
Michael L O'Byrne1, Laura Mercer-Rosa, Eitan Ingall
1Division of Pediatric Cardiology, Children's Hospital of Philadelphia, 34th Street and Civic Center Boulevard, Philadelphia, PA 19147, USA. obyrnem@email.chop.edu
Maximal oxygen consumption (VO2max) in patients with palliated congenital heart disease (CHD) correlates more strongly with habitual exercise than cardiac function. This suggests noncardiac factors influence exercise capacity in this population.
Area of Science:
- Cardiology
- Exercise Physiology
- Pediatric Cardiology
Background:
- Maximal oxygen consumption (VO2max) from cardiopulmonary exercise testing (CPET) is used to evaluate outcomes in palliated congenital heart disease (CHD).
- Previous research suggested VO2max reflects cardiac performance, but the influence of habitual exercise remains understudied in this cohort.
Purpose of the Study:
- To investigate the correlation between habitual exercise and VO2max in patients with palliated CHD.
- To compare the association of habitual exercise with VO2max against cardiac function measures obtained via cardiac magnetic resonance imaging (CMR).
Main Methods:
- Retrospective assessment of habitual exercise behavior via questionnaire in 208 subjects with conotruncal abnormalities.
- Analysis of data collected during previously performed CPET and CMR.
- Statistical testing to determine the association between VO2max, exercise duration, and CMR-derived ventricular function parameters.
Main Results:
- A significant correlation was found between hours of habitual exercise per week and VO2max (r² = 0.14, p < 0.001).
- No significant association was observed between VO2max and left or right ventricular ejection fraction, cardiac index, or right ventricular end-diastolic volume.
- VO2max correlated more strongly with habitual exercise duration than with ventricular function metrics.
Conclusions:
- Habitual exercise is a stronger correlate of VO2max than cardiac function in relatively healthy patients with palliated CHD.
- Noncardiac factors significantly influence exercise capacity in this population and should be considered during interpretation of CPET data.
- Further research is warranted to explore the impact of these factors on clinical outcomes.
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