Abstract 16601: Improvement in Biventricular Performance and Atrioventricular Interaction After Transcatheter Pulmonary Valve Replacement in Patients With Right Ventricular Outflow Tract Obstruction
Background: Transcatheter pulmonary valve replacement (TPV) offers catheter-based treatment for right ventricular outflow tract obstruction (RVOTO). Although TPV did not improve ventricular ejection fraction in prior studies, little is known about the impact of relieving chronic RVOTO on more subtle indices of ventricular function or atrioventricular interaction.
Objectives: To investigate the effect of relief of RVOTO on atrial and ventricular function and to clarify the relationship between atrial and ventricular systolic function in patients with CHD after TPV.
Methods: We studied 21 consecutive patients with significant RVOTO (mean Doppler gradient 34±14mmHg) and less than mild pulmonary regurgitation who underwent TPV using the Melody® valve for treatment of RVOTO (median age 17 years). Pulsed wave tissue Doppler imaging and LV paradoxical interventricular septal (IVS) motion index were performed immediately before and 6 months after TPV.
Results: TPV reduced the RVOTO mean gradient from 34±14 to 13±4 mmHg and RV pressure from 65±28 to 46±20 mmHg. Ventricular systolic peak velocity (S’) improved in the RV free wall (9.1±1.6 to 10±2.3 cm/s, p=0.05), the IVS (7±1.1 to 8±1.2 cm/s, p=0.006) and the LV free wall (8.4±1.7 to 10±2.7 cm/s, p=0.008). Early diastolic peak velocity (E’) improved in the IVS only (p=0.001). Left atrial late diastolic peak velocity (A’) decreased (6.5±1.7 to 5.9±1.6 cm/s, p=0.01), while right atrial A’ showed a reduction trend from pre-TPV to 6 months (7.4±2.4 to 6.5±2.4 cm/s, p=0.12). Global RV function after TPV improved by isovolumic contraction and relaxation time shortening (IVCT and IVRT), resulting in a Tei index decrease (0.52±0.14 to 0.39±0.11, p=0.005). Likewise, global LV function improved, with a global Tei index decrease (0.42±0.09 to 0.36±0.07, p=0.003) due to IVRT shortening. Improvement in biventricular function was associated with a reduction in LV septal bowing during systole and diastole using paradoxical IVS motion index (p<0.001 and p=0.001, respectively).
Conclusions: Improved biventricular global, systolic, and diastolic function after relief of RVOTO with TPV was associated with more favorable interventricular septal motion and less atrial contribution to ventricular filling.
- © 2011 by American Heart Association, Inc.