Abstract 1979: Left Ventricular Systolic Dysfunction Improves After Pulmonary Valve Replacement for Pulmonary Insufficiency in Adults With Repaired Tetralogy of Fallot
Background: Existing literature examining the impact of pulmonary valve replacement (PVR) after tetralogy of Fallot (TOF) repair largely focuses on right ventricular (RV) form and function. Although biventricular interactions have been recognised, left ventricular (LV) systolic function has not been well defined in adults after PVR.
Objective: We sought to investigate the impact of PVR on LV systolic function in adults with repaired TOF and pulmonary insufficiency.
Methods: Adults with repaired TOF and cardiac magnetic resonance imaging (CMR) studies analyzing biventricular volumes and function pre and post-PVR for severe pulmonary regurgitation between January 2003 and December 2008 at a single institution were included.
Results: CMR was performed (median 1.3 years post PVR, range 0.4 to 3.5) in 24 adults with repaired TOF (mean age at initial TOF 8±9 years and at PVR 35±11 years; 71% male). After PVR, pulmonary regurgitation decreased from 45±10% to 2±6% (P<0.0001) and RV volumes decreased (end-diastolic 224<40 to 139±30 ml/m2; end-systolic 147±35 to 93±27 ml/m2, P<0.0001, respectively). RV EF did not improve (35±9 to 34±6%, P=0.60). Ratio of RV/LV end-diastolic volumes decreased (2.6±0.5 to 1.6±0.3, P<0.0001). The pre-operative LV EF was significantly depressed (≤45%) in 8 patients. In this sub-group, LV EF improved (39±8 to 49±6%, P<0.001) whereas LV EF did not change significantly in the remaining cohort (54±5 to 57±6%, P=0.08). LV end-systolic volume decreased in those with pre-operative LV EF ≤45 % (P=0.017) and did not change in those with LV EF >45% (P=0.81). After PVR, in patients with pre-operative LV EF ≤45%, LV cardiac output and LV stroke volumes increased (5.3±1.3 to 6.4±1.6 l/min and 69±12 to 89±22 ml; P=0.028, respectively). In the remaining cohort, the improvement of LV cardiac output and LV stroke volumes was less striking in terms of absolute numbers although still statistically significant (5.4±1.2 to 6.0±1.2 l/min and 76±16 to 85±20 ml; P=0.011 and 0.016, respectively).
Conclusions: In adults with repaired TOF and significantly depressed LV systolic function, PVR for important pulmonary regurgitation results in significant improvement in LV EF and cardiac output.