Dallaire F; Wald RM; Marelli A,

Pediatric Cardiology [Pediatr Cardiol], ISSN:
1432-1971, 2017 Aug; Vol. 38 (6), pp. 1097-1105;

Tetralogy of Fallot is the most common form of
cyanotic congenital heart disease. As a result of the surgical
strategies employed at the time of initial repair, chronic pulmonary
regurgitation (PR) is prevalent in this population. Despite sustained
research efforts, patient selection and timing of pulmonary valve
replacement (PVR) to address PR in young asymptomatic patients with
repaired tetralogy of Fallot (rToF) remain a fundamental but as yet
unanswered question in the field of congenital heart disease. The
ability of the heart to compensate for the chronic volume overload
imposed by PR is critical in the evaluation of the risks and benefits
of PVR. The difficulty in clarifying the functional impact of PR on the
cardiovascular capacity may be in part responsible for the uncertainty
surrounding the timing of PVR. Cardiopulmonary exercise testing (CPET)
may be used to assess abnormal cardiovascular response to increased
physiologic demands. However, its use as a tool for risk stratification
in asymptomatic adolescents and young adults with rToF is still
ill-defined. In this paper, we review the role of CPET as a potentially
valuable adjunct to current risk stratification strategies with a focus
on asymptomatic rToF adolescents and young adults being considered for
PVR. The role of maximal and submaximal exercise measurements to
identify young patients with a decreased or borderline low peak VO2
resulting from impaired ventricular function is explored. Current
knowledge gaps and research perspectives are highlighted.