Right Ventricular Mass is Associated with Exercise Capacity in Adults with Repaired Tetralogy of Fallot

O’Meagher, Shamus; Seneviratne,
Martin; Skilton, Michael; Munoz, Phillip; Robinson, Peter; Malitz,
Nathan; Tanous, David; Celermajer, David; Puranik, Rajesh.

Pediatric Cardiology, August 2015, Vol. 36 Issue: Number 6 p1225-1231, 7p;
Abstract: The relationship between exercise capacity and right
ventricular (RV) structure and function in adult repaired tetralogy of
Fallot (TOF) is poorly understood. We therefore aimed to examine the
relationships between cardiac MRI and cardiopulmonary exercise test
variables in adult repaired TOF patients. In particular, we sought to
determine the role of RV mass in determining exercise capacity.
Eighty-two adult repaired TOF patients (age at evaluation
26 ± 10 years; mean age at repair 2.5 ± 2.8 years; 23.3 ± 7.9 years
since repair; 53 males) (including nine patients with tetralogy-type
pulmonary atresia with ventricular septal defect) were prospectively
recruited to undergo cardiac MRI and cardiopulmonary exercise testing.
As expected, these repaired TOF patients had RV dilatation (indexed RV
end-diastolic volume: 153 ± 43.9 mL/m2), moderate–severe pulmonary
regurgitation (pulmonary regurgitant fraction: 33 ± 14 %) and preserved
left (LV ejection fraction: 59 ± 8 %) and RV systolic function (RV
ejection fraction: 51 ± 7 %). Exercise capacity was near-normal (peak
work: 88 ± 17 % predicted; peak oxygen consumption: 84 ± 17 %
predicted). Peak work exhibited a significant positive correlation with
RV mass in univariate analysis (r= 0.45, p< 0.001) and (independent of
other cardiac MRI variables) in multivariate analyses. For each 10 g
higher RV mass, peak work was 8 W higher. Peak work exhibits a
significant positive correlation with RV mass, independent of other
cardiac MRI variables. RV mass measured on cardiac MRI may provide a
novel marker of clinical progress in adult patients with repaired TOF.