[III-JCKAP7-1-1] Comprehensive Approach to Refractory Pulmonary Vein Obstruction: Upgrade Stenting and Sirolimus Administration
キーワード：stent, pulmonary vein stenosis, sirolimus
<Background> Pulmonary vein (PV) obstruction (PVO) is a fatal complication of repaired total anomalous pulmonary venous connection. Stent implantation is a successful choice of approach; however, recurrent in-stent restenosis is common and the management of the refractory in-stent stenosis in PVO has not been established. We have been performing a comprehensive approach to refractory PVO, which includes surgical stent removal of previously implanted stents with markedly thickened intima and re-implantation of larger-sized new stents, a procedure defined as "Upgrade stenting." Additionally, sirolimus, an mTOR inhibitor was administered, to prevent further in-stent stenosis by upregulating myofibroblasts. <Patients> Up-grade stenting was performed for10 PVs in three patients. Seven of initially implanted stents were small or medium size and three were large. Through the recurrent reintervention, the stents was removed due to the insufficient patency. After stent removal, vessel lumens were widely open following gradual re-stenosis in all PVs approximately one month after stent removal. Upgrade stenting was performed percutaneously for the PVs with large size stent. Marked reduction of reintervention in majority of stents. Two out of the three patients were administered sirolimus for in-stent stenosis, aiming for further improvement in patency. <Conclusion> Although further follow-up is mandatory, upgrade stenting following removal of previously implanted small size stents combined with mTOR inhibitor may improve the outcome of refractory PVO.