Guidelines for the surveillance ofpatients with stents

Stenting was introduced for treating obstructive lesions of the peripheral or visceral vessels both as a primary procedure and after percutaneous angioplasty. Stents are of different sizes and materials, with a metal structure hav- ing a closed mesh (closed cells), open mesh (open cells) or variable geometry (hybrids), cylindrical or conical, bare or covered with synthetic material, final or reabsorbing, pre- mounted on balloon or self-expandable. This feature is of particular concern for intra-procedural assessment of the stenting in those cases in which this assessment when the procedure is performed without angiography. Some old steel stents cannot be assessed by AngioMR. On the other hand, the conformation and the materials stents can change the velocity of endoluminal flow, the ad- hesion to the vessel wall and the anatomic pattern of the vessel more or less significantly. Investigations — Standard radiography (Xray) — Color-coded Duplex scanning (CDS) basal and after administration of US amplifier — Angiography by computed tomography (AngioCT) — Angiography by magnetic resonance (AngioMR) — Digital subtraction angiography (DSA) — Intravascular ultrasound (IVUS) Advantages and disadvantages are described in the chapter about monitoring patients aortic endoprostheses. The sole purpose of the X-ray is to assess the position of the stent or its dislocation or its structural alterations and rupture. CDS alone is practically adequate to assess the stents positioned in all peripheral or visceral areas. Both the an- gioCT and angioMR are used in those districts where CDS is unable to provide exhaustive answers to the questions required by a “complete” check. DSA is used only in checking the stenting intraprocedur- ally or in subsequent endovascular operations. The parameters of a “complete” surveillance of a stent- ing procedure are: — In the site of the stent − Complete opening and patency of the stent − Complete coverage of the lesion − Presence of material inside the stent (the lesion protruding from the mesh of the stent, new athero- ma, hyperplasia/restenosis, thrombus) − Adhesion of the stent to the wall of the vessel − Dissecations/Rupture of the vessel wall − Structural modifications of the stent − Thrombosis of the vessels − Presence of angulations (kinking) or other modifi- cations of the anatonomy of the vessel Stenting was introduced for treating obstructive lesions of the peripheral or visceral vessels both as a primary pro- cedure and after percutaneous angioplasty. Stents are of different sizes and materials, with a metal structure hav- ing a closed mesh (closed cells), open mesh (open cells) or variable geometry (hybrids), cylindrical or conical, bare or covered with synthetic material, final or reabsorbing, pre- mounted on balloon or self-expandable. This feature is of particular concern for intra-procedural assessment of the stenting in those cases in which this assessment when the procedure is performed without angiography. Some old steel stents cannot be assessed by AngioMR. On the other hand, the conformation and the materials stents can change the velocity of endoluminal flow, the ad- hesion to the vessel wall and the anatomic pattern of the vessel more or less significantly. Investigations — Standard radiography (Xray) — Color-coded Duplex scanning (CDS) basal and after administration of US amplifier — Angiography by computed tomography (AngioCT) — Angiography by magnetic resonance (AngioMR) — Digital subtraction angiography (DSA) — Intravascular ultrasound (IVUS) Advantages and disadvantages are described in the chapter about monitoring patients aortic endoprostheses. The sole purpose of the X-ray is to assess the position of the stent or its dislocation or its structural alterations and rupture. CDS alone is practically adequate to assess the stents positioned in all peripheral or visceral areas. Both the an- gioCT and angioMR are used in those districts where CDS is unable to provide exhaustive answers to the questions required by a “complete” check. DSA is used only in checking the stenting intraprocedur- ally or in subsequent endovascular operations. The parameters of a “complete” surveillance of a stent- ing procedure are: — In the site of the stent − Complete opening and patency of the stent − Complete coverage of the lesion − Presence of material inside the stent (the lesion protruding from the mesh of the stent, new athero- ma, hyperplasia/restenosis, thrombus) − Adhesion of the stent to the wall of the vessel − Dissecations/Rupture of the vessel wall − Structural modifications of the stent − Thrombosis of the vessels − Presence of angulations (kinking) or other modifi- cations of the anatonomy of the vessel Stenting was introduced for treating obstructive lesions of the peripheral or visceral vessels both as a primary pro- cedure and after percutaneous angioplasty. Stents are of different sizes and materials, with a metal structure hav- ing a closed mesh (closed cells), open mesh (open cells) or variable geometry (hybrids), cylindrical or conical, bare or covered with synthetic material, final or reabsorbing, pre- mounted on balloon or self-expandable. This feature is of particular concern for intra-procedural assessment of the stenting in those cases in which this assessment when the procedure is performed without angiography. Some old steel stents cannot be assessed by AngioMR. On the other hand, the conformation and the materials stents can change the velocity of endoluminal flow, the ad- hesion to the vessel wall and the anatomic pattern of the vessel more or less significantly. Investigations — Standard radiography (Xray) — Color-coded Duplex scanning (CDS) basal and after administration of US amplifier — Angiography by computed tomography (AngioCT) — Angiography by magnetic resonance (AngioMR) — Digital subtraction angiography (DSA) — Intravascular ultrasound (IVUS) Advantages and disadvantages are described in the chapter about monitoring patients aortic endoprostheses. The sole purpose of the X-ray is to assess the position of the stent or its dislocation or its structural alterations and rupture. CDS alone is practically adequate to assess the stents positioned in all peripheral or visceral areas. Both the an- gioCT and angioMR are used in those districts where CDS is unable to provide exhaustive answers to the questions required by a “complete” check. DSA is used only in checking the stenting intraprocedur- ally or in subsequent endovascular operations. The parameters of a “complete” surveillance of a stent- ing procedure are: — In the site of the stent − Complete opening and patency of the stent − Complete coverage of the lesion − Presence of material inside the stent (the lesion protruding from the mesh of the stent, new athero- ma, hyperplasia/restenosis, thrombus) − Adhesion of the stent to the wall of the vessel − Dissecations/Rupture of the vessel wall − Structural modifications of the stent − Thrombosis of the vessels − Presence of angulations (kinking) or other modifi- cations of the anatonomy of the vessel − Coverage/occlusion of bifurcations and/or collat- eral circulation − Migration of the stent − Intrastent flow velocity (PSV – EDV) — Downstream of the stent − Micro/macro embolism — At the site of percutaneous access − Thrombosis − Dissection − AV fistula − Pseudoaneurysm − Hematoma − Lesions due to the mechanical closing systems