TY - JOUR
T1 - Relation of right ventricular mechanics to exercise tolerance in children after tetralogy of Fallot repair
AU - Friedberg, Mark K.
AU - Fernandes, Fernanda P.
AU - Roche, Susan L.
AU - Slorach, Cameron
AU - Grosse-Wortmann, Lars
AU - Manlhiot, Cedric
AU - Fackoury, Cheryl
AU - McCrindle, Brian W.
AU - Mertens, Luc
AU - Kantor, Paul F.
N1 - Funding Information:
This work was supported by the National Grants Program of the Canadian Institutes of Health Research and Sickkids Foundation . The authors are solely responsible for the design and conduct of this study; all study analyses, the drafting and editing of the paper, and its final contents.
PY - 2013/4
Y1 - 2013/4
N2 - Background Progressive right ventricular (RV) dysfunction and exercise intolerance are common problems after tetralogy of Fallot (TOF) repair. We investigated RV myocardial deformation and dyssynchrony in children after TOF repair and their association with exercise capacity. Methods Asymptomatic children after TOF repair were investigated by 2-dimensional speckle tracking echocardiography, magnetic resonance, and metabolic exercise study. Patients with RV outflow obstruction were excluded. Peak RV longitudinal strain and strain rate (SR) and dyssynchrony (RV intraventricular delay) were compared with healthy controls. Associations between RV strain, dyssynchrony, and exercise capacity were analyzed. Results Thirty-nine (81%) of 48 TOF patients and 40 healthy controls had adequate RV strain imaging. The TOF patients had moderately dilated RVs and normal RV ejection fraction. Right ventricular peak systolic strain (-23.2% ± 5.1% vs -28.5% ± 8.5%, P <.001) and SR (-1.46 ± 0.68 vs -2.1 ± 0.8, P <.001) were reduced in TOF patients compared with controls. Right ventricular intraventricular delay was higher in TOF patients (146.0 ± 159 vs 71.0 ± 92 milliseconds, P =.008). Decreased RV strain and SR were associated with increased RV dyssynchrony (strain parameter estimate [PE] 6.31 [2.30], P =.007; SR [PE] 11.32 [3.84], P =.004). Increased RV-left ventricular delay was associated with prolonged QRS duration (PE 0.13 [0.058], P =.03) and reduced RV ejection fraction (PE -2.95 [1.275], P =.02). Reduced RV peak SR was associated with decreased exercise peak oxygen uptake (PE 0.14 [0.07], P =.04). Conclusions After repair of TOF, asymptomatic children have reduced RV deformation in association with RV dyssynchrony and reduced exercise tolerance.
AB - Background Progressive right ventricular (RV) dysfunction and exercise intolerance are common problems after tetralogy of Fallot (TOF) repair. We investigated RV myocardial deformation and dyssynchrony in children after TOF repair and their association with exercise capacity. Methods Asymptomatic children after TOF repair were investigated by 2-dimensional speckle tracking echocardiography, magnetic resonance, and metabolic exercise study. Patients with RV outflow obstruction were excluded. Peak RV longitudinal strain and strain rate (SR) and dyssynchrony (RV intraventricular delay) were compared with healthy controls. Associations between RV strain, dyssynchrony, and exercise capacity were analyzed. Results Thirty-nine (81%) of 48 TOF patients and 40 healthy controls had adequate RV strain imaging. The TOF patients had moderately dilated RVs and normal RV ejection fraction. Right ventricular peak systolic strain (-23.2% ± 5.1% vs -28.5% ± 8.5%, P <.001) and SR (-1.46 ± 0.68 vs -2.1 ± 0.8, P <.001) were reduced in TOF patients compared with controls. Right ventricular intraventricular delay was higher in TOF patients (146.0 ± 159 vs 71.0 ± 92 milliseconds, P =.008). Decreased RV strain and SR were associated with increased RV dyssynchrony (strain parameter estimate [PE] 6.31 [2.30], P =.007; SR [PE] 11.32 [3.84], P =.004). Increased RV-left ventricular delay was associated with prolonged QRS duration (PE 0.13 [0.058], P =.03) and reduced RV ejection fraction (PE -2.95 [1.275], P =.02). Reduced RV peak SR was associated with decreased exercise peak oxygen uptake (PE 0.14 [0.07], P =.04). Conclusions After repair of TOF, asymptomatic children have reduced RV deformation in association with RV dyssynchrony and reduced exercise tolerance.
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U2 - 10.1016/j.ahj.2012.06.029
DO - 10.1016/j.ahj.2012.06.029
M3 - Article
C2 - 23537972
AN - SCOPUS:84875440131
SN - 0002-8703
VL - 165
SP - 551
EP - 557
JO - American heart journal
JF - American heart journal
IS - 4
ER -