Rosenblum, Omer; Katz,
Uriel; Reuveny, Ronen; Williams, Craig; Dubnov-Raz, Gal.

Pediatric Cardiology, December 2015, Vol. 36 Issue: Number 8 p1573-1581, 9p;

Abstract: Few previous studies have addressed exercise capacity in
patients with corrected congenital heart disease (CHD) and significant
anatomical residua. The aim of this study was to determine the aerobic
fitness and peak cardiac function of patients with corrected CHD with
complete or incomplete repairs, as determined by resting
echocardiography. Children, adolescents and young adults (<40 years)
with CHD from both sexes, who had previously undergone biventricular
corrective therapeutic interventions (n= 73), and non-CHD control
participants (n= 76) underwent cardiopulmonary exercise testing. The
CHD group was further divided according to the absence/presence of
significant anatomical residua on a resting echocardiogram
(“complete”/“incomplete” repair groups). Aerobic fitness and cardiac
function were compared between groups using linear regression and
analysis of covariance. Peak oxygen consumption, O2pulse and
ventilatory threshold were significantly lower in CHD patients compared
with controls (all p< 0.01). Compared with the complete repair group,
the incomplete repair group had a significantly lower mean peak work
rate, age-adjusted O2pulse (expressed as % predicted) and a higher
VE/VCO2ratio (all p≤ 0.05). Peak oxygen consumption was comparable
between the subgroups. Patients after corrected CHD have lower peak and
submaximal exercise parameters. Patients with incomplete repair of
their heart defect had decreased aerobic fitness, with evidence of
impaired peak cardiac function and lower pulmonary perfusion. Patients
that had undergone a complete repair had decreased aerobic fitness
attributed only to deconditioning. These newly identified differences
explain why in previous studies, the lowest fitness was seen in
patients with the most hemodynamically significant heart
malformations.