Preoperative Hemodynamics Impact the Benefit of Fenestration on Fontan Postoperative Length of Stay.

BACKGROUND

Utilization of Fontan fenestration varies considerably by center.

OBJECTIVES

Using a multicenter Pediatric Heart Network dataset linking surgical and preoperative hemodynamic variables, the authors evaluated factors associated with use of Fontan fenestration and the impact of fenestration on post-Fontan length of stay (LOS).

METHODS

Patients 2 to 6 years old at Fontan surgery from 2010 to 2020 with catheterization<1 year prior were included. Factors associated with fenestration were evaluated using multivariable logistic regression adjusting for key covariates. Restrictive cubic spline analysis was used to evaluate potential cut-points for hemodynamic variables associated with longer postoperative LOS stratified by fenestration with multivariable linear regression to evaluate the magnitude of effect.

RESULTS

Fenestration was used in 465 of 702 patients (66.2%). Placement of a fenestration was associated with center (range 27%-93% use, P < 0.0001) and Fontan type (OR: 14.1 for lateral tunnel vs extracardiac conduit, P < 0.0001). No hemodynamic variable was independently associated with fenestration. In a multivariable linear model adjusting for center, a center-fenestration interaction, prematurity, preoperative mean pulmonary artery pressure (mPAP), and cardiac index, fenestration was associated with shorter hospital LOS after Fontan (P = 0.0024). The benefit was most pronounced at mPAP ≥13 mm Hg (median LOS: 9 vs 12 days, P = 0.001).

CONCLUSIONS

There is wide center variability in use of Fontan fenestration that is not explained by preoperative hemodynamics. Fenestration is independently associated with shorter LOS, and those with mPAP ≥13 mm Hg at pre-Fontan catheterization benefit the most. We propose this threshold as minimal criteria for fenestration.