Michael Gawenda

Endovascular Treatment of Mycotic Aortic Aneurysms A European Multicenter Study

Background— Mycotic aortic aneurysm (MAA) is a rare and life-threatening disease. The aim of this European multicenter collaboration was to study the durability of endovascular aortic repair (EVAR) of MAA, by assessing late infection–related complications and long-term survival. Methods and Results— All EVAR treated MAAs, between 1999 and 2013 at 16 European centers, were retrospectively reviewed. One hundred twenty-three patients with 130 MAAs were identified. Mean age was 69 years (range 39–86), 87 (71%) were men, 58 (47%) had immunodeficiency, and 47 (38%) presented with rupture. Anatomic locations were ascending/arch (n=4), descending (n=34), paravisceral (n=15), infrarenal aorta (n=63), and multiple (n=7). Treatments were thoracic EVAR (n=43), fenestrated/branched EVAR (n=9), and infrarenal EVAR (n=71). Antibiotic was administered for mean 30 weeks. Mean follow-up was 35 months (range 1 week to 149 months). Six patients (5%) were converted to open repair during follow-up. Survival was 91% (95% confidence interval, 86% to 96%), 75% (67% to 83%), 55% (44% to 66%), and 41% (28% to 54%) after 1, 12, 60, and 120 months, respectively. Infection-related death occurred in 23 patients (19%), 9 after discontinuation of antibiotic treatment. A Cox regression analysis demonstrated non-Salmonella–positive culture as predictors for late infection–related death. Conclusions— Endovascular treatment of MAA is feasible and for most patients a durable treatment option. Late infections do occur, are often lethal, and warrant long-term antibiotic treatment and follow-up. Patients with non-Salmonella–positive blood cultures were more likely to die from late infection. # CLINICAL PERSPECTIVE {#article-title-32}Background— Mycotic aortic aneurysm (MAA) is a rare and life-threatening disease. The aim of this European multicenter collaboration was to study the durability of endovascular aortic repair (EVAR) of MAA, by assessing late infection–related complications and long-term survival. Methods and Results— All EVAR treated MAAs, between 1999 and 2013 at 16 European centers, were retrospectively reviewed. One hundred twenty-three patients with 130 MAAs were identified. Mean age was 69 years (range 39–86), 87 (71%) were men, 58 (47%) had immunodeficiency, and 47 (38%) presented with rupture. Anatomic locations were ascending/arch (n=4), descending (n=34), paravisceral (n=15), infrarenal aorta (n=63), and multiple (n=7). Treatments were thoracic EVAR (n=43), fenestrated/branched EVAR (n=9), and infrarenal EVAR (n=71). Antibiotic was administered for mean 30 weeks. Mean follow-up was 35 months (range 1 week to 149 months). Six patients (5%) were converted to open repair during follow-up. Survival was 91% (95% confidence interval, 86% to 96%), 75% (67% to 83%), 55% (44% to 66%), and 41% (28% to 54%) after 1, 12, 60, and 120 months, respectively. Infection-related death occurred in 23 patients (19%), 9 after discontinuation of antibiotic treatment. A Cox regression analysis demonstrated non-Salmonella–positive culture as predictors for late infection–related death. Conclusions— Endovascular treatment of MAA is feasible and for most patients a durable treatment option. Late infections do occur, are often lethal, and warrant long-term antibiotic treatment and follow-up. Patients with non-Salmonella–positive blood cultures were more likely to die from late infection.

Endotension as a Result of Pressure Transmission through the Graft following Endovascular Aneurysm Repair—An In vitro Study

BACKGROUND endovascular aneurysm repair (EVAR) significantly reduces, but does not abolish aneurysm sac pressure, possibly because of trans-fabric transmission. OBJECTIVE to investigate how blood pressure is transmitted through different types of grafts into the aneurysm sac. DESIGN experimental study, in vitro. METHODS a latex aneurysm was inserted into an in vitro circulation model. The systemic mean pressure (SPmean) was varied from 50 to 120 mmHg. The grafts used for aneurysm exclusion were: thin wall polyethylene (PE), thick wall polyethylene (PE) and thin wall ePTFE. Mean aneurysm sac pressure (ASPmean) was measured, as was pulse pressure (ASPpulse). RESULTS at an SPmean of 70 mmHg, the ASPmean was 34 +/- 0.8 mmHg (polyethylene knitted, thick wall), 30 +/- 1.0 mmHg (polyethylene woven, thin wall), and 17 +/- 0.6 mmHg (thin wall ePTFE). The ASPmean increased with SPmean, the relationship depending on the graft material. Stiffer grafts were associated with lower ASPmean and ASPpulse (p<0.001). CONCLUSIONS the relationship between aneurysm sac mean pressure and systemic pressure (SP) depends on the graft material. These data highlights the need for further studies regarding endotension.

Meta-analysis of endovenous radiofrequency obliteration of the great saphenous vein in primary varicosis.

Purpose: To compare radiofrequency obliteration (RFO) and conventional surgery with respect to postoperative complications, effectiveness of treatment, and quality of life (QoL). Methods: Several healthcare databases were interrogated to identify all studies published between 1994 and 2007 comparing RFO in primary varicosis to conventional therapy with vein ligation and stripping. Of 65 articles identified, 8 studies representing 428 patients [224 (52%) endovenous RFO and 204 (48%) stripping] were eligible for the meta-analysis. Adverse events, effectiveness, and QoL outcomes were assessed at several time points up to 2 years. Results: There were significant reductions in tenderness and ecchymosis at 1 week and significantly fewer hematomas at 72 hours, 1 week, and 3 weeks associated with RFO. There was no significant difference between the RFO and surgery in immediate or complete great saphenous vein (GSV) occlusion, incomplete GSV closure, freedom from reflux, recurrent varicose veins, recanalization, or neovascularization. QoL results significantly favoring RFO over surgery included return to normal activity and return to work. Conclusion: It seems that RFO benefits most patients in the short term, but rates of recanalization, re-treatment, occlusion, and reflux may alter with longer follow-up. The lack of such data demonstrates the need for further randomized clinical trials of RFO versus conventional surgery.

Open versus endovascular repair of para-anastomotic aneurysms in patients who were morphological candidates for endovascular treatment.

Purpose: To compare the outcomes of open versus endovascular repair of para-anastomotic aneurysms (PAA) in the aortic and iliac arteries in a cohort of patients who fulfilled morphological criteria for endovascular repair. Methods: A retrospective review of 31 consecutive patients with PAA treated between 1985 and 2002 identified 26 (84%) patients who would have been candidates for endovascular repair based on preoperative computed tomography and angiography. Of these 26 patients, 10 (9 men; median age 65 years, range 60–75) underwent endovascular repair; the remaining 16 patients (14 men; median age 61.5 years, range 49–78) had open repair. The baseline data and outcome measures were compared between the treatment groups. Results: The patient groups were well matched for age, sex, weight, risk factors, comorbidities, aneurysm length, and elapsed time from initial graft placement. Both groups had technically successful PAA repairs; however, median blood loss (300 versus 1000 mL; p = 0.05) and procedural time (100 versus 215 minutes; p<0.001) were significantly reduced in the endovascular group. Median transfusion volume was significantly greater (1000 versus 0 mL; p = 0.01) in the surgically treated patients. The median stay in ICU was similar (18 versus 24 hours in the surgical cohort). Length of stay was significantly shorter in the endovascular group: 7.5 versus 17.0 days (p = 0.001) after the repair and 11 versus 22 days (p = 0.01) for overall hospitalization. One (10%) patient in the endovascular group died from a myocardial infarction on the third postoperative day. In the open group, there were 3 (19%) procedure-related deaths. Conclusions: Patients with PAA who were endograft candidates but who were treated with open repair experienced more morbidity and had more complications than patients treated with stent-grafts. If long-term follow-up demonstrates durable results, stent-graft repair may become the therapy of choice in PAAs.

New insights regarding the incidence, presentation and treatment options of aorto-oesophageal fistulation after thoracic endovascular aortic repair: the European Registry of Endovascular Aortic Repair Complications

OBJECTIVES To review the incidence, clinical presentation, definite management and 1-year outcome in patients with aorto-oesophageal fistulation (AOF) following thoracic endovascular aortic repair (TEVAR). METHODS International multicentre registry (European Registry of Endovascular Aortic Repair Complications) between 2001 and 2011 with a total caseload of 2387 TEVAR procedures (17 centres). RESULTS Thirty-six patients with a median age of 69 years (IQR 56-75), 25% females and 9 patients (19%) following previous aortic surgery were identified. The incidence of AOF in the entire cohort after TEVAR in the study period was 1.5%. The primary underlying aortic pathology for TEVAR was atherosclerotic aneurysm formation in 53% of patients and the median time to development of AOF was 90 days (IQR 30-150). Leading clinical symptoms were fever of unknown origin in 29 (81%), haematemesis in 19 (53%) and shock in 8 (22%) patients. Diagnosis could be confirmed via computed tomography in 92% of the cases with the leading sign of a new mediastinal mass in 28 (78%) patients. A conservative approach resulted in a 100% 1-year mortality, and 1-year survival for an oesophageal stenting-only approach was 17%. Survival after isolated oesophagectomy was 43%. The highest 1-year survival rate (46%) could be achieved via an aggressive treatment including radical oesophagectomy and aortic replacement [relative risk increase 1.73 95% confidence interval (CI) 1.03-2.92]. The survival advantage of this aggressive treatment modality could be confirmed in bootstrap analysis (95% CI 1.11-3.33). CONCLUSIONS The development of AOF is a rare but lethal complication after TEVAR, being associated with the need for emergency TEVAR as well as mediastinal haematoma formation. The only durable and successful approach to cure the disease is radical oesophagectomy and extensive aortic reconstruction. These findings may serve as a decision-making tool for physicians treating these complex patients.

Balloon Occlusion of the Celiac Artery: A Test for Evaluation of Collateral Circulation Prior Endovascular Coverage

INTRODUCTION Visceral ischemia is a possible complication after endovascular coverage of the celiac artery (CA). A selective mesenteric angiography during simultaneous balloon occlusion of the CA imitates endovascular coverage and might therefore be suited for evaluation of collateral circulation. We report the feasibility of a balloon occlusion test (BOT) of the CA for this purpose. REPORT We performed a BOT in 5 patients selected for endovascular surgery with intended coverage of the CA. The BOT could demonstrate sufficient collateral circulation in all cases, which was not evident without occlusion of the CA. The most important collateral vessels were the pancreaticoduodenal arcades and the dorsal pancreatic artery. All patients tolerated the BOT well without abdominal symptoms or pathological laboratory findings. DISCUSSION Our report suggests that a BOT of the CA is a feasible and safe procedure. It can demonstrate collateral pathways before definite coverage is performed. This test might be useful for selection of patients prior intended coverage of the CA.

Evidence that Statins Protect Renal Function During Endovascular Repair of AAAs

OBJECTIVES Several studies have documented a slight but significant deterioration of renal function after endovascular repair of abdominal aortic aneurysm (AAA) (EVAR). The aim of this retrospective study was therefore to investigate whether medication with statins may favourably affect perioperative renal function. MATERIAL AND METHODS From January 2000 to January 2008, out of a total cohort of 287 elective patients receiving endovascular repair of their AAA or aortoiliac aneurysm, 127 patients were included in the present study, as their medication was reliably retrievable. Patients were divided according to whether their medication included statins (>3 months). Second, they were subdivided according to their supra- (SR) or infrarenal (IR) endograft fixation. Serum creatinine (SCr) and creatinine (CrCl) clearance were determined preoperatively, postoperatively, at 6 and 12 months. Patients with known pre-existing renal disease, with incorrect placement of the stent graft resulting in severe renal artery stenosis, and with occlusion or renal parenchymal infarction were excluded from the study. RESULTS Patients receiving an infrarenal fixation of their graft had no change in the renal function, regardless whether they were on statins or not. In patients with SR fixation not receiving statins, a deterioration in renal function was observed in the early postoperative period ((SCr) preoperative vs. SCr postoperative: 1.02±0.2 vs. 1.11±0.28, p<0.001 and (Cr.Cl) preoperative vs. Cr.Cl postoperative: 74.1±21.4 vs. 68.0±21.4, p<0.001), whereas patients on statins experienced no change in renal function (SCr preoperative vs. SCr postoperative: 0.99±0.24 vs. 1.02±0.20n.s. and Cr.Cl preop vs. Cr.Clpostop.: 76.4±19.1 vs. 74.28±20.50, n.s.). During follow-up, a constant worsening of renal function at 6 and 12 months was observed, irrespective of the medication with statins. CONCLUSIONS The present study suggests a slight immediate deterioration of the renal function using (SR) fixation, and this could be prevented by the use of statins. During follow-up, statins did not protect from further renal deterioration. Broader studies are needed to confirm a definitive relation between statin use and renal protection during the endovascular repair of AAA.

Endovascular Aneurysm Repair of Aortoiliac Aneurysms with an Iliac Side-branched Stent graft: Studying the Morphological Applicability of the Cook Device

OBJECTIVE/BACKGROUND Endovascular aneurysm (EVAR) repair of an aortic aneurysm extending to the iliac artery remains a challenge. Interventional occlusion of the internal iliac artery (IIA) intending to create a distal landing zone in the external iliac artery is a common approach with inherent morbidity (e.g., buttock claudication, impotence). Alternatively, iliac side-branched stent grafts can maintain pelvic blood supply, but the applicability is limited. The objective was to investigate the morphological applicability of the Cook Zenith branched graft (ZBIS) among patients with aorto-iliac or isolated iliac aneurysms. METHODS This was a retrospective single centre analysis of 66 patients (60 men; median age 74 years, range 53-90 years) undergoing repair of aorto-iliac aneurysms (open repair, IIA occlusion prior to EVAR and ZBIS) between January 2008 and December 2012. All available computed tomography angiograms with post-processing imaging were compared with the criteria for morphological applicability to (i) the manufacturers instruction for use (IFU), and (ii) to criteria published in the literature, as well as (iii) to the institutional protocol. RESULTS In 66 patients, 88 targeted iliac aneurysms were studied. Of these, 36/88 (40.9%) were compliant with the manufacturers IFU, 35/88 (39.8%) were compliant with the published criteria, and 51/88 (58.0%) were compliant with the in house protocol. The most common morphological exclusion criterion was an aneurysmal IIA. CONCLUSION In the present cohort with aorto-iliac aneurysm, a maximum of 58% could have been treated with an iliac side branch based on the current experience. In particular, an aneurysmal IIA seems to be a limiting factor for the use of the iliac side-branched stent graft.

Buttock Claudication After Interventional Occlusion of the Hypogastric Artery—A Mid-Term Follow-Up

Background. Interventional occlusion of the hypogastric artery (HA) can be used for endovascular aneurysm repair (EVAR) in the iliac arteries. Most frequent ischemic complication is buttock claudication (BC). Aim. To investigate the frequency and progression of BC after interventional occlusion of the HA prior to EVAR. Methods. A retrospective analysis was performed in patients with EVAR and occlusion of the HA between September 2004 and August 2010. Acute and persistent BC symptoms were assessed. Results. Fifty-four catheter occlusions of the HA were performed. In 10 cases, claudication could not be evaluated. During a mean follow-up of 17 months, 23 occlusions (52.3%) of the HA showed BC, in 52% symptoms were persistent. Of the 5 patients, 3 patients who underwent bilateral occlusion had BC and in 2 cases, persistent in the follow-up. Conclusion. Buttock claudication after occlusion of the HA prior to EVAR is a frequent complication, which often persists during follow-up. Alternatives that maintain pelvic perfusion should be considered.

Successful treatment of a type-II endoleak with percutaneous CT-guided thrombin injection in a patient after endovascular abdominal aortic aneurysm repair

The persistence of blood flow outside the graft but inside the aneurysm sac after endovascular treatment of the AAA is called endoleak. Strategies of treatment vary depending on the type of endoleak. Type-II endoleaks are usually treated by intraarterial embolization of the feeding vessels; however, this may be tedious, time-consuming, and sometimes impossible. We treated a 77-year-old man with a type-II endoleak after uneventful endograft (Zenith, Cook, William Europe, Denmark) placement with CT-guided injection of thrombin. A small endoleak originating from a persistent flow through a lumbar artery was detected by contrast-enhanced helical CT (Fig. 1) and intraarterial angiography. Selective catheterization of the lumbar artery via the internal iliac artery was twice technically impossible. Firstly, a pigtail catheter was placed in the aorta. After the patient was positioned in a prone position, a helical CT scan was performed while contrast medium was injected (30 ml, 5 ml/s) via the pigtail catheter in order to confirm the localization of the endoleak. A CT-guided puncture was performed with a 22-cm-long needle (diameter 0.7 mm; Fig. 2). L E T T E R T O T H E E D I T O R