Abstract
In the sheep model with pathophysiologic changes similar to patients with repaired TOF, severe PR leads to fibrotic changes in the RV. Pulmonary valve replacement reverses these fibrotic changes. Early valve replacement led to a quick RV recovery, and in time there was no difference in outcome between early and late valve replacement. These data support the benefit of valve replacement for RV function and suggest that there is a margin in the timing of the surgery. The fibrotic changes correlated well with the circulating biomarker PICP, which can have an added value in the clinical follow-up of patients with repaired TOF.