Abstract 9363: Intervention for Re-coarctation in the Single Ventricle Reconstruction Trial: Incidence, Risk and Outcomes
Objectives: To determine the incidence of re-coarctation (re-CoA), risk factors and outcomes in patients with single right ventricle lesions after Norwood.
Methods: The cohort included subjects randomized to right ventricle-pulmonary artery shunt (RVPAS) or modified Blalock Taussig shunt (MBTS) in the Single Ventricle Reconstruction (SVR) Trial. Re-CoA was defined by intervention, either catheter-based or surgical. Univariate analysis and multivariable Cox proportional hazard models were performed adjusting for center.
Results: Of the 549 SVR subjects, 97 (18%) underwent 137 interventions (92 balloon aortoplasty; 45 surgical) for re-CoA. Intervention typically occurred at pre-stage II catheterization (n=71, 52%) or at stage II surgery (n=44, 32%). Median age and catheterization gradient at first intervention were 4.9 months (range: 1.1-10.5) and 17 mm Hg (range: 0-60) respectively. Center intervention rates varied from 0-50%. In multivariable analysis, re-CoA was not associated with assigned shunt type, but was associated with actual shunt type received (HR 2.0 for RVPAS vs. MBTS, p=0.02), and Norwood discharge peak echo-Doppler arch gradient (HR 1.07 per 1 mm Hg, p<0.01). No other demographic, anatomic or surgical variables predicted intervention. Subjects with re-CoA demonstrated comorbidities at pre-stage II evaluation including higher pulmonary arterial pressures (15.4 ± 3.0 vs. 14.5 ± 3.5 mm Hg; p=0.05), higher pulmonary vascular resistance (2.6 ± 1.6 vs. 2.0 ± 1.0 WU x m²; p=0.04) and increased echocardiographic volumes (end-diastolic volume: 28.0 ± 7.4 vs. 24.9 ± 8.2 ml; p=0.01). There was no difference in 12-month post-randomization transplant-free survival for those with and without re-CoA (83% vs. 86%; p=0.5).
Conclusions: Intervention for re-CoA was common and varied by center. The association with receipt of an RVPAS may be due to intra-operative cross-over because of arch anatomy that prohibited use of a MBTS. Those undergoing intervention demonstrated ventricular dilation and worsened hemodynamics prior to stage II surgery. Although intervention was not associated with increased 1-year transplant/mortality, further evaluation is warranted to evaluate effects of morbidity of re-CoA.
- © 2012 by American Heart Association, Inc.