Matthieu Guillou

Endovascular treatment of thoracoabdominal aortic aneurysms

BACKGROUND Development in endograft design has extended endovascular treatment to include thoracoabdominal aortic aneurysms (TAAA). We report our experience using fenestrated and branched endografts in the management of TAAA. METHODS We analyzed a cohort of consecutive patients treated electively for TAAA using endovascular techniques between 2006 and 2011. All data were collected prospectively. The relationships between preoperative risk factors and clinical outcome were examined using univariate and multivariate statistical techniques. We also compared the outcomes between 33 previously published early cases (EC) with the last 56 later cases (LC). RESULTS Eighty-nine patients (83 men) were treated. Median age was 69 years. All patients were deemed unfit for open surgery. The 30-day and in-hospital mortality rates were 8.9% and 10%, respectively. Multivariate analysis showed in-hospital mortality was associated with preoperative chronic renal failure and advanced age. Higher postoperative mean arterial blood pressure was a protective factor. Technical success rate was 96.6% (94% and 98% in the EC and LC groups, respectively; P = .14). The spinal cord ischemia (SCI) rate was 7.8% (15% and 3% in the EC and LC groups, respectively; P = .063) and was associated with chronic obstructive pulmonary disease and procedure duration. Six patients (6.7%) required temporary filtration, but none required permanent renal support (associated with left ventricular ejection fraction <40% and procedure duration). Median procedure duration decreased from 232 to 203 minutes (P = .01) in the EC and LC groups, respectively. Actuarial survival was 86.8% ± 3.7% at 1 year and 74.7% ± 6% at 2 years. CONCLUSIONS Although we have treated a cohort at high operative risk, our midterm results compare favorably with the published series of conventional surgery. Accurate hemodynamic control represented by high-normal perioperative blood pressure seems to protect against severe postoperative complications.

Off-the-Shelf Fenestrated Endografts: A Realistic Option for More Than 70% of Patients With Juxtarenal Aneurysms

Purpose To evaluate the suitability of a standardized fenestrated endograft in patients with juxtarenal abdominal aortic aneurysms. Methods High resolution computed tomographic angiograms from 100 consecutive patients (96 men; mean age 72 years) with juxta- (n=78) and pararenal (n=22) aneurysms treated electively between 2005 and 2010 with custom-made fenestrated endografts were reviewed. A centerline of flow reconstruction was carried out in a 3D imaging workstation to precisely define the aortic morphology, including aortic diameters and distances between visceral and renal arteries. The applicability of 2 different “off-the-shelf” standardized fenestrated endografts designed by the manufacturer was evaluated in this cohort. Both designs included 2 fenestrations for the renal arteries, 1 for the superior mesenteric artery (SMA), and a scallop for the celiac trunk. The designs differed in the lengths of the SMA to renal fenestration and renal to renal fenestration. Results Endovascular treatment with one or both “off-the-shelf” endografts was deemed possible in 72 patients (56 with design 1, 52 with design 2, and 36 with both endografts). Of the 28 patients who were not candidates for a standardized fenestrated stent-graft of either design, the primary cause was a right renal artery that did not match the position of its corresponding fenestration. Conclusion Standardized fenestrated designs suitable for endovascular treatment of >70% of patients with juxta- and pararenal aneurysms currently treated with custom-made fenestrated endografts will soon be available. This new generation of endografts will permit rapid treatment of a large majority of patients requiring fenestrated endograft repair.

Evaluation of Radiation during EVAR Performed on a Mobile C-arm

BACKGROUND The aim of this study was to evaluate radiation exposure during aortic endovascular aneurysm repair (EVAR) on a mobile C-arm using a low dose and pulse mode. METHODS We performed a retrospective analysis of a prospectively maintained database on patients undergoing EVAR. Indirect dose measurements of dose area product (DAP, mGy m²) calculated by the C-arm (OEC 9900MD), fluoroscopic time (FT), type of procedure, contrast media volume and body mass index were analysed. To confirm the correlation between direct and indirect DAP measurements, direct dose was measured with radiochromic films on a sample of 15 patients. Film grey level response was calibrated according to a reference dose measurement performed with a calibrated dosimeter. DAP and peak skin dose (PSD, Gy) were measured on each film. Correlation between DAP from direct and indirect measures, and between DAP and PSD, were analysed. RESULTS From January 2009 to April 2011, 335 patients underwent EVAR. Complete data were available on 301 procedures including 188 bifurcated, 54 fenestrated, 28 thoracic, 20 branched and 11 aorto-uni-iliac endografts implantation. The respective median FT and DAP was 9.36 min (1.8-67) and 3 mGy m(2) (0.4-28); 27.2 min (2-69) and 7.3 mGy m(2) (1.2-29); 7.75 min (1.2-19.1) and 2 mGy m(2) (0.3-11); 42.98 min (2.4-95.4) and 15.95 mGy m(2) (2.98-77.7); 6.2 min (0.5-36.3) and 2 mGy m(2) (0.3-11). Direct DAP measurement on radiochromic films was strongly correlated with DAP values provided by the C-arm (r = 0.98). PSD correlated weakly with DAP. DAP was significantly increased (p < 0.001) in patients with a body mass index >30. Contrast media volume was significantly increased in the branched endograft group. CONCLUSION Indirect DAP values measured by the C-arm are accurate to evaluate radiation exposure. Compared to the literature, our values for standard procedures are significantly decreased by the usage of low dose and pulse mode. DAP for fenestrated and branched procedures was comparable to published DAP values with standard procedures using a regular fluoroscopic mode.

Anatomic Study of Juxta Renal Aneurysms: Impact on Fenestrated Stent-Grafts

BACKGROUND Fenestrated stent-grafts allow for treatment of patients with juxtarenal aneurysms (JRA) when they present with contraindications for conventional treatment. The fenestrated module is a custom-made module, specially designed to fit a specific patient, using computed tomographic scan measurements, which entails manufacturing delay and high cost. The aim of our study was to evaluate the possibility to reproduce the interrenal aorta anatomy to design a standard fenestrated module that would fit the maximum number of patients with JRA. METHODS On a three-dimensional working station, we analyzed 289 preoperative computed tomographic scan results of patients with JRA and who were treated with fenestrated stent-grafts comprising two fenestrations for the renal arteries and a scallop for the superior mesenteric artery (SMA). On curvilinear reconstructions, we successively measured the interrenal aorta diameter, its orientation, as well as the height of each renal ostium, taking the ostium center of the SMA as a reference mark. Later, a statistical analysis of these measures distribution was performed so as to design a fenestrated module that would fit the maximum number of patients. RESULTS The center of the left renal artery presented with a median orientation of 82.5° (range, 37.5-150) and a median distance of 9 mm (range, 0-30), in relation to the SMA ostium. The ostium center of the right renal artery presented with a median orientation of 285° (range, 240-337.5) and a median distance of 8 mm (range, 3-30), in relation to the SMA ostium. By positioning the current renal fenestrations (6-mm wide), on the basis of the calculated median positions, in our series, only 20% of the patients could be treated with a standard fenestrated module. Should the diameter of these fenestrations be increased by 10 mm, it would then be possible to treat 50% of our patients. CONCLUSION The anatomy of the interrenal aorta and its branches is quite reproducible to design standard fenestrated stent-grafts that could treat half of the patients with JRA.

Comparison of Short- and Mid-Term Follow-Up Between Standard and Fenestrated Endografts

BACKGROUND This study compared early and mid-term results of endovascular treatment for abdominal aortic aneurysms (AAAs) and pararenal aneurysms (PRAs). METHODS Using data from a prospective database, patients treated with endografts for AAA and PRA between January 2007 and December 2009 were analyzed. In both groups, mortality, endoleak rates, evolution of renal function, reintervention rate at 30 days and at mid-term follow-up, and aneurysmal sac evolution at 1 year were compared. RESULTS In total, 379 patients were included: 264 treated for AAA and 115 for PRA. Median follow-up was 24 months (range 12-46 months) in both groups. Risk factors and medical history were comparable in both groups, except for chronic renal failure (higher in the PRA group; P = 0.003). The mortality rates at 30 days were 1% and 3% in the AAA and APR groups, respectively (P = 0.10). During follow-up, the mortality rates were 11.1% and 12.8% in the AAA and PRA groups, respectively (P = 0.72). The reoperation rates at 30 days were 8% and 10% in the AAA and PRA groups, respectively (P = 0.72). During follow-up, the reoperation rates were 9.2% and 9.9% in the AAA and PRA groups, respectively (P = 0.85). At 1 year, retraction of the aneurysmal sac was diagnosed in 48% of the patients in the AAA group and in 56% of the patients in the PRA group (P = 0.41). The incidence rates of new postoperative cases of renal insufficiency were 19.3% and 8.1% in the AAA and PRA groups, respectively (P = 0.008). At 30 days, the endoleak rates were 27.5% and 12.7% in the AAA and PRA groups, respectively (P = 0.001). At 1 year, the endoleak rates were 19.4% and 7.3% in the AAA and PRA groups, respectively (P = 0.007). When type II endoleaks were excluded, the endoleak rates were comparable in both groups (P = 0.5). At 1 year, in both groups, a retraction of the aneurysmal sac was significantly correlated to the absence of endoleak (P = 0.001). CONCLUSION Early and mid-term results of AAA treatment with standard endografts and PRA treatment with fenestrated endografts are comparable.

Challenging treatment of a secondary endoleak in a fenestrated endograft.

Purpose: To describe the novel use of an Amplatzer occluder device to seal a secondary endoleak arising at a scallop in a fenestrated stent-graft. Case Report: A 67-year-old man with comorbidities precluding standard endovascular repair of a pararenal aortic aneurysm was treated with a fenestrated endoprosthesis containing one fenestration for the left renal artery and one scallop for the celiac trunk; the right renal and superior mesenteric arteries were occluded at presentation. Interval imaging at 2 years showed a proximal type I endoleak at the celiac trunk scallop associated with expansion of the aneurysm sac. Attempted repair with an aortic extension cuff and a “chimney” stent was unsuccessful. An Amplatzer Patent Foramen Ovale occluder device was deployed across the endoleak to provide aneurysm sac exclusion, which has been maintained at 6-month follow-up. Conclusion: Treatment of a secondary type I endoleak after implantation of a fenestrated endoprosthesis is challenging. The novel use of an Amplatzer occluder in this setting may be applicable to other situations in which an endovascular solution is desirable for complications of complex endovascular aneurysm repair.

Inverted Limbs in Fenestrated and Branched Endografts

Purpose: To describe our experience with the use of custom-designed branched or fenestrated endoprostheses incorporating an inverted contralateral limb in the bifurcated component. Methods: Retrospective analysis was performed of a prospectively maintained database of all patients undergoing endovascular aneurysm repair using modular branched or fenestrated devices at a university teaching hospital between January 2004 and February 2010. Of 102 cases, 7 male patients (mean age 69 years) were treated with modular devices that incorporated an inverted contralateral limb in the bifurcated component. Five patients had thoracoabdominal aortic aneurysm (4 type IV and 1 type II), 1 patient had a pararenal abdominal aortic aneurysm, and another had type I endoleak from a migrated AneuRx stent-graft. The technique was used primarily because of an existing bifurcated prosthesis (n=5), but in 2 patients without prior open surgery, this technique was needed because of anatomical constraints. Results: All devices were implanted as planned. There was no mortality. One patient required temporary hemodialysis prior to discharge; another patient developed permanent paraplegia, likely related to extensive aortic coverage. No device migration, component separation, or type I or III endoleaks were detected during a mean follow-up of 25 months, and no reinterventions have been necessary. Conclusion: The use of an inverted limb in the bifurcated component of modular endografts may allow endovascular treatment in scenarios where there is insufficient space to deploy a standard bifurcated component. This design modification allows an adequate sealing zone between the iliac extension limbs and the bifurcated component.

Ambulatory Peripheral Angioplasty: The Experience of a Private Center

one was ineffective and one early was followed by an early rethrombosis) and required two bypasses. Seven of these thromboses occurred before the seventh month. Four PAs finally required a bypass. No patient presented acute sensory-motor ischemia or a loss of downstream arteries. None was amputated. Conclusion: Two interpretations of these results are possible. A pessimistic interpretation notes that there were eight thromboses out of 22 treated PAs (36%). An optimistic interpretation notes that 82% of the PAs (18/22) avoided conventional surgery. This study suggests that it is necessary to refine the indications of the VS and the improvement of the stentgraft (heparin fixation?) could be an option.

Endovascular Applications for Thoracoabdominal Pathologies

This chapter describes and discusses several graft designs to accommodate the various anatomy configurations of thoracoabdominal aneurysms. The discussion will include the selection of a branch, a fenestration, or a scallop to perfuse a visceral vessel arising from the diseased aorta or located at the level of the sealing zone. Unusual cases will also be presented.

Endovascular Applications for Aortoiliac Pathologies

In this chapter, two cases of iliac artery aneurysms are presented. The first one is a “classic” bilateral common iliac artery aneurysm associated with a left internal iliac artery aneurysm that was managed with an iliac branch device on the right and an embolization of the contralateral internal iliac. The latter case is a more complex one: due to the extreme tortuosity of the iliac axes, a retroperitoneal approach was performed to straighten the access arteries, allowing a smoother advancement of the endograft.