Savino G. Sardella

Noninvasive diagnosis of incomplete endovascular aneurysm repair: D-dimer assay to detect type I endoleaks and nonshrinking aneurysms.

PURPOSE To test the hypothesis that D-dimer (D-D), a cross-linked fibrin degradation product of an ongoing thrombotic event, could be a marker for incomplete aneurysm exclusion after endovascular abdominal aortic aneurysm (AAA) repair. METHODS In a multicenter study, 83 venous blood samples were collected from 74 AAA endograft patients and controls. Twenty subjects who were >6 months postimplantation and had evidence of an endoleak and/or an unmodified or increasing AAA sac diameter formed the test group. Controls were 10 nondiseased subjects >65 years old, 18 AAA surgical candidates, and 26 postoperative endograft patients with no endoleak and a shrinking aneurysm. Blood samples were analyzed for D-D through a latex turbidimetric immunoassay. The endograft patients were stratified into 5 clinical groups for analysis: no endoleak and decreasing sac diameter, no endoleak and increasing/unchanged sac diameter, type II endoleak and decreasing sac diameter, type II endoleak and increasing/unchanged sac diameter, and type I endoleak. RESULTS Individual D-D values were highly variable, but differences among clinical groups were statistically significant (p < 0.0001). D-D values did not vary significantly between patients with stable, untreated AAAs and age-matched controls (238 +/- 180 ng/mL versus 421 +/- 400 ng/mL, p > 0.05). Median D-D values increased at 4 days postoperatively (963 ng/mL versus 382 ng/mL, p > 0.05) and did not vary thereafter if there was no endoleak and the aneurysm sac decreased. D-D mean values were higher in patients with type I endoleak (1931 +/- 924 ng/mL, p < 0.005) and those with unchanged/increasing sac diameters (1272 +/- 728 ng/mL) than in cases with decreasing diameters (median 638 +/- 238 ng/mL) despite the presence of endoleak (p < 0.0005). CONCLUSIONS Elevated D-D may prove to be a useful marker for fixation problems after endovascular AAA repair and may help rule out type I endoleak, thus excluding patients from unnecessary invasive tests.

Ultrasonographic Surveillance with Selective CTA after Endovascular Repair of Abdominal Aortic Aneurysm

Purpose: To evaluate the agreement between color-coded duplex ultrasound (US) and computed tomographic angiography (CTA) in monitoring aneurysm diameter and detecting endoleaks after endovascular aneurysm repair (EVAR). Methods: From November 1998 to January 2007, 196 patients (191 men; mean age 72.4 years, range 52–88) underwent EVAR and were followed by CTA and US over a mean 3.9±2.4 years (range 0––8.9, median 3.4). Annual paired CTA and US examinations were reviewed to assess agreement in measuring maximum aneurysm transverse diameter and to evaluate diagnostic accuracy of US in detecting endoleak. Results: The 5-year cumulative endoleak incidence was 43.8% (72 patients). At first diagnosis, US detected 55/72 (76.4%) endoleaks; of the remaining 17, only 3 (4.3%) were clinically significant in terms of aneurysm enlargement. Pairing 709 annual CTA and US examinations from 184 patients showed a high agreement (k=0.96) between examinations in measuring maximum transverse diameter, with a mean difference between US and CTA of −2.5 mm. Conclusion: After the first year of follow-up, EVAR surveillance costs can be reduced by performing annual US examinations only. Keeping in mind that US underestimates diameter measurements, CTA can be reserved for patients with increasing or persistently stable aneurysm diameters.

Endovascular repair of an aorto-left renal vein fistula due to a ruptured abdominal aortic aneurysm after EVAR.

Purpose: To report an unusual late complication of endovascular aneurysm repair: an arteriovenous fistula between the aneurysm sac and a retro-aortic left renal vein following sac expansion due to a type III endoleak. Case Report: A 79-year-old man developed an arteriovenous fistula between the aneurysm sac and a retro-aortic left renal vein 67 months after endovascular aneurysm exclusion (EVAR). Aneurysm rupture was due to disconnection between the right iliac limb and an extender cuff. The problem was repaired percutaneously with another endograft bridging the two prostheses. At 16 months, the aneurysm sac diameter was decreased; there was no evidence of the AV fistula, and the patient was free from any complication related to the EVAR. Conclusions: This case emphasizes the need of close surveillance even in the late postoperative course of these patients. Moreover, this rare event confirmed that endovascular techniques can play an important role in treating emergent complications.

Endoluminal treatment of abdominal aortic aneurysms

AbstractBackground: We report our preliminary results with endovascular treatment of abdominal aortic aneurysms (AAA). Methods: Between October 1998 and June 2000, 64 patients (62 male, two female; mean age = 70 years) underwent endovascular repair of AAA. Different types of prostheses were used, both bifurcated (n= 58) and straight (n= 6). We performed duplex sonography and spiral computed tomographic angiography (CTA) at discharge and at 3, 6, 12, and 18 months. Follow-up ranged from 1 to 20 months. Results: All procedures were successful, except for three immediate and one late surgical conversions (6.2%). One patient died 14 days after immediate surgical conversion. At discharge, CTA showed 13 endoleaks: three resolved spontaneously, six persisted during follow-up, and four (one angioplasty and three embolizations) were treated successfully. Stenosis of an iliac branch occurred in one patient after 3 months and was successfully treated by angioplasty. Late endoleaks were detected by imaging follow-up in four cases, three at 1 year and one at 6 months, requiring deployment of distal extender cuffs (n= 2), a proximal cuff (n= 1), and lumbar embolization (n= 2). Conclusion: Our preliminary experience supports the efficacy of endovascular repair in selected patients, but strict and accurate follow-up is required.