Early outcomes of thoracic endovascular stent-graft repair for acute complicated type B dissection using the Gore TAG endoprosthesis.

We assessed the technical success and early outcome of thoracic endovascular aortic repair (TEVAR) for complicated acute type B thoracic aortic dissection treated at a single institution using a commercially available device. All patients with symptomatic complicated acute type B thoracic aortic dissection treated with TEVAR since Food and Drug Administration approval of the Gore (Flagstaff, AZ) TAG endoprosthesis were identified from a prospectively maintained vascular registry. Clinical indications, operative technique, perioperative complications, follow-up imaging, and mortality were analyzed. Between March 2005 and November 2007, 127 TEVARs using the TAG endoprosthesis were performed, of which 15 (11.8%) were for complicated acute type B thoracic aortic dissection. Indications for repair were malperfusion (53%), persistent pain (27%), and primary aortic failure (33%). Technical feasibility and success with deployment proximal to the entry tear was 93.3%, requiring at least partial coverage of the left subclavian artery in seven (46.7%). Adjunctive procedures required at the time of TEVAR included renal stent (n = 2), iliac stent (n = 3), and access-artery open repair (n = 2). Twelve patients (80%) had immediate resolution of the malperfusion deficit. Major perioperative complications included paraplegia (13.3%), renal failure requiring hemodialysis (13.3%), and stroke (6.7%). Perioperative mortality was 13.3%, occurring in one patient presenting with rupture and one with profound heart failure on admission. For complicated acute type B thoracic aortic dissection, TEVAR using commercially available stent grafts showed high technical success, excellent results at resolving malperfusion, and acceptably low complications and perioperative mortality.

Should endovascular repair be used for small abdominal aortic aneurysms?

The outcomes of endovascular repair for small abdominal aortic aneurysm (4.0-4.9 cm) is reported. All patients undergoing endovascular abdominal aortic aneurysm repair between 2000 and 2006 with maximal diameter 4.0 to 4.9 cm form the small aneurysm study cohort. Data were analyzed retrospectively and life-table methods were used. Of 743 endovascular repairs, 132 (17.8%) were performed for small abdominal aortic aneurysm. Perioperative complication rate was 9.1%. Freedom from aneurysm expansion was 96% at 1 year, 86% at 3 years, and 77% at 5 years. Overall survival was 98%, 93%, and 84% at 1, 3, and 5 years, respectively. Perioperative 30-day mortality was 0.8% with an aneurysm-related mortality of 1.5% at 5 years. There were no deaths from delayed aneurysm rupture. Endovascular repair of small abdominal aortic aneurysm is associated with low perioperative morbidity and mortality compared with published results for open repair, and treatment threshold can be reduced to 4 cm in selected patients.

Effect of warfarin anticoagulation on below-knee polytetrafluoroethylene graft patency.

When polytetrafluoroethylene (PTFE) must be used for below-knee bypass to achieve limb salvage, effective anticoagulation with warfarin may improve graft survival. We analyzed our practice of routinely using oral anticoagulation to improve graft patency rates for PTFE grafts to below-knee popliteal and crural vessels in limb salvage procedures. We reviewed our established vascular database from February 1999 through April 2003 to identify those patients who required below-knee and tibial artery bypass with PTFE for critical limb ischemia. All patients were initiated on warfarin anticoagulation postoperatively, with an international normalized ratio (INR) of 2.0-3.0 considered therapeutic. All patients were discharged in the therapeutic range. Life-table analysis and Kaplan-Meier estimates were used to compare primary patency rates with regard to INR and position of distal anastomosis. Cox proportional hazards analysis was performed to compare the patency rates for grafts with therapeutic versus subtherapeutic anticoagulation while correcting for variability in distal runoff. Between February 1999 and April 2003, 74 patients (mean age, 69.2 years; 58% men) had 77 below-knee PTFE bypasses. Indications for operation included rest pain (43), ischemic ulcer (27), and gangrene (7). Patients presenting with occluded grafts more often had a subtherapeutic INR. Patients with a subtherapeutic INR (< or = 1.9) had a median primary graft patency of 6.8 months and those with a therapeutic INR (> or = 2.0) had a median primary graft patency of 29.9 months (p = 0.0007). Analysis by Cox proportional hazards model demonstrated a significantly better graft patency rate in patients with a therapeutic INR regardless of outflow vessel. The patency rates of PTFE grafts to infrageniculate vessels may be improved by effective anticoagulation with warfarin. This improved patency rate may also result in improved limb salvage and further support the use of PTFE grafts for critical limb ischemia when autogenous vein is not available. Predictably, the best results are seen with an INR therapeutic range of 2.0 to 3.0.