The outcome of pulmonary artery stents following surgical manipulation

Abstract

Background: Pulmonary artery (PA) stents are utilized to treat branch pulmonary stenosis (BPS). Often patients with PA stents undergo subsequent cardiac surgery for other indications, and the stents can be manipulated during the procedure.

Objective: The purpose of this study was to evaluate the outcome of branch PA stenoses following surgical manipulation of previously implanted PA stents and to determine factors associated with future reintervention.

Methods: Catheterization data, operative reports, and clinical summaries were reviewed on patients with PA stents placed between September 1989 and December 2006 undergoing subsequent cardiac surgery. Surgical manipulation was recorded as removed, trimmed, or longitudinally transected, and patched. Those that were not manipulated were defined as untouched.

Results: 459 patients had branch PA stents placed. About 54 patients, with 70 stents in branch PA's. subsequently had further cardiac surgery. The median age of stent placement was 7.5 (0.5-32.4) years with a median age of surgery of 12.7 (5.1-39.6) years. Surgical manipulation was performed in 23 (33%) PA's and 47 (66%) stents were untouched. Stent removal occurred in 11 (16%), with transecting longitudinally and patching in 5 (7%), and trimming in 7 (10%). Comparing the surgical manipulation and the untouched groups, there was no difference in median age of stent placement [7.2 (0.5-30.2) versus 7.6 (1.8-32.4) years, p=0.40], wt [21.0 (5.3-86.5) versus 24.7 (9.0-96.0) kg, p=0.42], or residual catheterization gradient across the stent [3 (0-59) versus 4 (0-50) mmHg, p=0.81]. Catheter reintervention (stent n=6 or balloon dilation n=14) on the previously stented PAs was similar between the surgically manipulated (median 7.5 years) and untouched groups (median 11.5 years) (p=0.31). In multivariate analysis, the factors associated with future catheter reintervention were having the stent transected longitudinally and patched (p=0.003) and a lower weight (p=0.006) at the time of stent placement.

Conclusions: Surgical stent manipulation is often performed in patients who have PA stents. Surgical manipulation does not alter the need for future reintervention and catheter re-intervention may be more likely when the stents are transected longitudinally and patched.