Pulmonary artery stents: long-term follow-up.

Objectives: Determine the long-term outcomes of branch pulmonary artery (PA) stents.

Background: PA stents in congenital heart disease effectively relieve stenoses in the short-term. Published long-term data are limited.

Methods: Patients enrolled in an FDA IDE protocol from 1989-92 were included. Clinical follow-up and catheterization data were evaluated. Patients were included if >5 year follow-up data was available or if mortality occurred following the initial procedure.

Results: There were five deaths: four due to progression of their underlying heart disease, and one from a complication during a follow-up catheterization. Clinical data for 43 surviving patients demonstrated 39 patients (91%) are in NYHA class I or II. Seven patients underwent surgical intervention during the follow-up period (five RV-PA conduit, two Fontan revisions), but none addressed PA stenosis. Final repeat catheterizations were performed in 36 patients (55 stents) 7.2 +/- 4.3 years post stent insertion with 1.2 +/- 0.9 further procedures with stent dilations. In this subgroup, the minimum vessel diameter increased from 4.7 +/- 1.8 to 13.4 +/- 2.4 mm (P < 0.001), and the pressure gradient improved from 41 +/- 25 to 9 +/- 11 mm Hg (P < 0.001). Higher initial gradient and smaller balloons were associated with a final stent diameter of <14 mm (P = 0.030 and 0.046). Jailed vessels occurred in 49% of stents with abnormal angiographic flow in 18/55. Six repeat catheterizations resulted in complications, including the one procedural death.

Conclusion: Stents implants for PA stenoses provide effective improvement in vessel caliber in the long-term. Although repeat interventions are necessary, this procedure reduces RV pressure and provides an important alternative to surgery for residual PA obstruction.