Side Cell Dilation of Jailed Pulmonary Veins After Stenting Improves Vessel Preservation in Pediatric Pulmonary Vein Stenosis.

INTRODUCTION

Endovascular stent placement for pulmonary vein stenosis (PVS) provides effective obstruction relief. Due to small patient size and limited length options of available stents, pulmonary vein branches can be covered ("jailed") during stenting. The natural history of jailed veins, and whether side cell dilation (SCD) modifies this natural history, is unknown.

METHODS

Pulmonary vein stents placed January 2017 to May 2024 at a single center were reviewed to determine if any veins were jailed during stent deployment. Jailed vein diameter was measured before stent placement. Subsequent SCD, and jailed vein patency at the most recent catheterization are reported. The relationship between jailed vein survival and SCD was evaluated by log rank test using SCD as a time varying covariate to account for patients who have delayed SCD.

RESULTS

Eighty-one stents were placed in 42 patients at a median of 9.1 months of age and 7.0 kg. 45 stents (56%) jailed at least one pulmonary vein branch. Excluding five stents without follow-up, 51 jailed veins were identified as the result of 40 stents placed in 20 patients. Immediate SCD was performed in 11 jailed veins (22%) and 24 additional jailed veins received SCD at a subsequent procedure, thus 35 jailed branches (69%) received SCD. With a median follow-up of 1.1 years, 35 jailed branches (69%) remained patent. The estimated jailed vein patency at 9 months for veins not receiving SCD was 70% (95% CI: 44%-86%) compared to 97% (95% CI: 79%-99%) for jailed veins that did receive SCD (log rank p = 0.005).

CONCLUSIONS

Jailing of pulmonary veins was common during stent placement for PVS in children. Without SCD, jailed vein patency is low. Jailed vein patency was significantly improved with SCD.