Augmentation of the pulmonary arteries is not associated with worse longer term outcome a propensity matched analysis from the Australia and New Zealand Fontan registry

Abstract

Background: Adequacy of the pulmonary arteries is essential for a durable Fontan circulation. Long-term data following pulmonary artery (PA) augmentation in association with the Fontan is lacking. Methods: Pre-operative, operative and follow-up data for 1437 patients in the Australia and New Zealand Fontan Registry (1975- 2015) was analysed. The primary endpoints were death and death or failure (takedown, transplant, PLE or plastic bronchitis). Cox regression with propensity score matching (1:1 nearest neighbour) was used to determine the risk or benefit conferred due to pulmonary artery augmentation. Results: 48 (3.3%) patients underwent PA augmentation after a cavopulmonary shunt but prior to Fontan (surgical n=14, balloon dilatation n=16, stent insertion n=19). 12 of these patients required further intervention at the time of Fontan (surgical=7, intraoperative stent=4, combined=1). A further 105 (7.6%) patients underwent PA augmentation at the time of Fontan (surgical=104, stent=1). Median follow-upwas 6.4 years with 10 deaths (6.5%) in the PA augmentation group and 10.5 years with 95 deaths (7.4%) in the non-augmentation group. Tests for frailty showed no significant variance in outcome between surgical centres or different decades. Initial unadjusted Kaplan-Meier log-rank and Cox regression demonstrated no significant difference in both endpoints between the 2 groups (death: HR 1.35, 95% CI 0.70-2.60, p=0.366; death or failure: HR 1.39, 95% CI 0.83-2.34, p=0.211). Propensity score matching yielded a total of 262 matched patients (131 in each group) with adequate balance for all covariates (median residual bias=0.05). Subsequent Cox regression demonstrated no significant difference in the risks of death (HR1.30, 95% CI 0.49-3.41, p=0.596) and death or failure (HR 0.92, 95% CI 0.46-1.85, p=0.817) Conclusion: The requirement for PA augmentation prior to or at Fontan does not confer worse longer-term outcomes. An aggressive approach towards PA augmentation for hypoplastic pulmonary arteries is justified in prospective Fontan patients. (Figure Presented).L6200779492018-01-09 <br />