Abstract 11082: Age Related Power Output and Power Loss in Tetralogy of Fallot Patients After Repair With Pulmonary Insufficiency: A Combined Cardiac Magnetic Resonance and Cardiac Catheterization Study With Implications for Pulmonary Valve Replacement
Background: It has been shown that pts after tetralogy of Fallot (TOF) repair with pulmonary regurgitation (PR) results in power loss with right ventricular (RV) power output decreasing with increased RV volume. The relationship with age has not been described.
Methods: Retrospective review of all TOF pts who had cardiac magnetic resonance (CMR) & cardiac catheterization (cath) within 6 months from 2005 till present. Pressures from cath and flows from CMR were used. Significance was P<0.05.
Results: 31 pts (ages 10.3+13 yrs) were found with N=18 for pts < 10 yrs & N=13 for pts >10 yrs. Older pts had higher forward RV power (1.1+0.6 vs 0.39+0.21 Watts (W), P<0.001), power loss from PR (0.14+0.14 vs 0.06+0.04 W P=0.02) & net power (0.94+0.52 vs 0.34+0.18 W, P<0.001) when compared with younger pts. Power loss increased as RV end-diastolic volume increased, especially in older pts (all pts, R=0.4, P=0.03; in older pts, R=0.91, P<0.001 - see Power Loss graph). Correlations existed in all pts with indexed RV power output as a dimensionless variable & RV end-diastolic volume (R=-0.58 to -0.77), power loss (R=-0.66) & left ventricular (LV) end-diastolic pressure (R=+0.37) all with P<0.04. See log Power Output graph.
Conclusions: TOF pts > 10 yrs have greater RV power output and power loss than younger pts, possibly due to pre-adolescent and adolescent changes. RV power output is related to RV end-diastolic volume, power loss & left ventricular end-diastolic pressure. Increased RV power output may come at the cost of LV end-diastolic pressure.These findings may suggest replacement of the pulmonary valve at earlier ages than is currently practiced.
- © 2012 by American Heart Association, Inc.