Abstract 19791: Echocardiography Derived Velocity Time Integral is Associated with Double Switch Outcomes in Congenitally Corrected Transposition of the Great Arteries
Introduction: Congenitally corrected transposition of the great arteries (CCTGA) is a rare form of congenital heart disease characterized by atrioventricular and ventriculoarterial discordance. Management is controversial; options include observation, physiologic repair and anatomic repair by the double switch operation (DSO). Assessment of morphologic left ventricle (LV) preparedness is key in determining DSO timing, although exact criteria are lacking. Cardiac MRI is the current standard technique to assess LV adequacy prior to DSO. The purpose of our study was to determine if echocardiographic (echo) or MRI measures of the LV predict outcomes.
Methods: A retrospective review of CCTGA patients eligible for DSO at Lucile Packard Children’s Hospital from 2000-2014 was conducted. Inclusion criteria were: 1) age <18 years, 2) adequate pre-surgical echo and MRI images and 3) clinical follow-up information available. Post-processing of echo images was performed to obtain measurements of LV structure and function. Measurements included 5/6 and 2/3 area-length ejection fraction (EF) and mass, LV eccentricity index, LV posterior wall thickness, LV tissue Doppler velocities, tricuspid valve regurgitation severity, pulmonary artery (PA) pressure gradient and PA velocity time integral (VTI). MRI measurements included LV mass and EF. Outcomes included achieving DSO and freedom from death, transplant and heart failure at last follow up.
Results: 31 patients met inclusion criteria (7.3 ± 7.8 years). Peak PA VTI correlated significantly with outcomes. Receiver operating curve analysis showed that a VTI of > 1.17cm predicted successful DSO and freedom from death, transplant and heart failure at last follow up, with a respective sensitivity of 80% and 83% and specificity of 86% and 78% (AUC 0.88-0.92, p < 0.0001). Inter and intra-observer variability for VTI measurements was excellent (intraclass correlation coefficients > 0.95). MRI and other echo measurements of LV mass and function as well as PA pressure gradient did not correlate with outcome.
Conclusion: PA VTI is a readily available and highly reproducible measurement that reflects morphologic LV performance and predicts outcomes in CCTGA patients better than conventional MRI assessment.
Author Disclosures: S. Moodley: None. S. Balasubramanian: None. T. Tacy: None. F. Hanley: None. F. Chan: None. R. Punn: None.
- © 2014 by American Heart Association, Inc.