Open Collections

Sha, Cindy (Hsin)

University of British Columbia

BACKGROUND: Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart defect. Infants with TOF typically receive surgical correction shortly after birth. Despite undergoing surgery, their exercise capacity (VO2peak) remains reduced. PURPOSE: This study explores the interplay between surgical, physiological and behavioural factors in adolescents with TOF. HYPOTHESIS: We hypothesised that a more complicated surgical course – indicated by having postoperative complication and extended hospital stay – along with left and right ventricular systolic dysfunction and a lack of participation in competitive sports would result in reduced % predicted VO₂peak. METHODS: A single-centre, retrospective review (January 2016 – September 2024) of TOF patients aged 11-18 who completed a maximal cardiopulmonary exercise test (CPET) within 6 months of their most recent resting echocardiogram (echo). Additional prospective data was collected: TOF adolescents aged 11 – 18 were recruited between May 2024 – October 2024. Along with standard echo, CPET, recreational physical activity levels, and sports participation data, adolescent participants also completed a motor skills (BOT-2 SF) assessment, and their parents filled out two questionnaires on their own physical activity levels. RESULTS: The median age at primary repair was 7.6 months (5.3-11.7), with the transannular patch surgical technique accounting for 65%. Participants (15.8 years, 14.2-17.5) had a lower % predicted VO₂peak (93, 64-91) compared to healthy adolescents, HRpeak (181bpm, 177-191), O₂pulse peak (10.2ml/beat, 8.7-13.4) and OUESkg (36.5,28.3—42.9). VE/VCO₂ slope was elevated (36.5,34.8 - 40.1). 64% of participants participated in recreational activity at least 2 days per week, and 18% participated in competitive sports. Statistical analysis identified the following predictor variables for % predicted VO₂peak: the occurrence of postoperative complications, hospital length of stay, body mass index (BMI), mitral valve (MV) A wave velocity, the number of recreational physical activity participation days and participation in competitive sports. The final model explained for 80.3% of the variance in % predicted VO₂peak, where BMI (p<0.001), MV A wave velocity (p=0.003) and competitive sports (<0.001) were significant predictors. CONCLUSION: Adolescents with TOF have a lower VO₂peak, which can be explained by body composition, left ventricular compliance, and participation in competitive sports.

Text

2025-01-09

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/90076

Kinesiology

University of British Columbia

UBCV

http://creativecommons.org/licenses/by-nc-nd/4.0/