Is Stent Placement Effective for Palliation of Right Ventricle to Pulmonary Artery Conduit Stenosis?

Abstract

This study was designed to evaluate the outcome of stent placement (SP) for conduit discrete stenosis using predefined criteria. Right ventricle (RV) to pulmonary artery (PA) conduits are often associated with complications, such as stenosis, requiring multiple surgical replacements. Patients who underwent primary or repeat SP were included. Indications for SP were clinical symptoms and/or RV to systolic blood pressure (SBP) ratio (RV:SBP) >0.65 by echocardiography. Our definition of success was a decrease in RV:SBP by >20%, a final RV:SBP ratio of <0.65, or resolution of symptoms. Stents were placed successfully in 28 of 31 patients (90%), including 3 patients who underwent the procedure solely for symptoms. The RV:SBP ratio decreased (0.75 +/- 0.17 vs. 0.52 +/- 0.12, p < 0.001), and the conduit diameter increased (postero-anterior 9.1 +/- 2.9 vs. 12.0 +/- 2.8 mm, lateral 8.3 +/- 2.2 vs. 11.6 +/- 2.4 mm, p < 0.001). In the 28 patients with successful SP, 8 (29%) remained free from second intervention. In the remaining patients, the median time to re-intervention was 16 months (range 6 to 44 months). Second transcatheter interventions (4 SP, 4 balloon dilation) were successful in 8 of 13 patients. Complications included balloon rupture (n = 4), stent fracture (n = 2), and pseudoaneurysm formation (n = 1). Initial SP has excellent intermediate outcomes, successfully postponing surgical intervention for the majority of patients. Conduit restenosis may be successfully treated with a second transcatheter intervention. On the basis of these data, SP is likely the procedure of choice for patients with a discrete stenosis of the RV to PA conduit.