Richard Azzaoui

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.

Endovascular Repair of Thoracoabdominal Aortic Aneurysms

OBJECTIVES To evaluate the early outcomes following thoracoabdominal aortic aneurysm (TAAA) repair utilising fenestrated and branched endografts. DESIGN AND MATERIALS AND METHODS: A prospective analysis of all patients undergoing endovascular repair of TAAA in a single academic centre. All patients were deemed unfit for open surgical repair. Customised endografts were designed using CT data reconstructed on 3D workstations. Post-operatively all patients were evaluated radiologically at hospital discharge, at 6, 12, 18 and 24 months, and annually thereafter. RESULTS Thirty-three consecutive patients (30 males) were treated over 33 months (August 2006 to April 2009). Median age and aneurysm size were 70 years (range 50-83 years) and 64 mm (range 55-100 mm) respectively. 114/116 (98%) of the targeted visceral vessels were successfully catheterised and perfused. The in-hospital mortality rate was 9% (3/33). Transient spinal cord ischaemia was diagnosed in 4/33 (12%) patients, and permanent paraplegia in one (3%). The median follow-up period was 11 months (range 1-33 months). Endoleaks were identified in 5/33 (15%) patients: type II in four patients and a type III endoleak in one patient which required the only secondary intervention. During follow-up, two patients died: one from stroke and the other from myocardial infarction 9 and 29 months respectively after the procedure. CONCLUSION This preliminary study, which includes our learning curve, confirms the feasibility and safety of the endovascular repair of TAAA in high-risk patients. Meticulous follow-up to assess sac behaviour and visceral perfusion is critical in order to ensure optimal results of these complex endovascular repairs requiring numerous mating components.

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.

Circumflex artery stenosis induced by intraoperative radiofrequency ablation.

We report a case of circumflex artery stenosis after intraoperative radiofrequency ablation for permanent atrial fibrillation in a patient who had a previous mitral valve replacement. The patient presented with acute pulmonary edema and severe angina 1 year after an uneventful recovery. The patient underwent a diagnostic angiography that showed the presence of stenosis of a long segment of the circumflex artery, adjacent to the radiofrequency ablation site, which was reopened successfully by angioplasty. Intraoperative radiofrequency ablation caused circumflex artery stenosis. We believe that this complication could have been avoided by applying the radiofrequency ablation more distally between the left pulmonary veins and the mitral valve.

The Benefits of EVAR Planning Using a 3D Workstation

OBJECTIVES To evaluate the influence of planning endovascular aneurysm repair (EVAR) with a three-dimensional (3D) workstation on early and midterm outcomes. METHODS All patients undergoing infrarenal EVAR performed between 2006 and 2009 at our institution were included in the current study. Prior to 2008 (group 1), endograft sizing was performed by interrogation of computed tomography angiography axial images. After 2008 (group 2), endograft sizing was routinely performed using a 3D workstation (Aquarius, Terarecon), allowing for multiplanar reconstruction and centerline analysis. Pre-, peri-, postoperative, and follow-up data were prospectively entered in an electronic database. All postoperative complications and subsequent secondary interventions depicted during the 2-year period following EVAR were compared. Secondary intervention and mortality rates were defined at 2 years and compared. Freedom from secondary intervention and overall survival rates were calculated using the Kaplan-Meier method during follow-up and compared by log-rank test. RESULTS A total of 295 patients (149 patients in group 1 and 146 patients in group 2) were included. All patients had completed a minimum of 2 years of follow-up. During this 2-year period following EVAR, the type 1 endoleak rate was 8.7% in group 1 and 1.4% in group 2 (p = .004) respectively. Secondary intervention rates related to type 1 endoleak was 5.4% in group 1 and 0 in group 2 (p < .001). No difference was observed regarding all-cause mortality, aneurysm-related death, and freedom from secondary intervention rates during follow-up. CONCLUSION The routine use of 3D workstations for EVAR planning significantly reduces the rate of type 1 endoleaks and, therefore, the rate of related secondary interventions.

Evaluation of Visceral Artery Displacement by Endograft Delivery System Insertion

Purpose To assess the displacement of the aorta and its visceral branch ostia after insertion of a rigid system including a stiff guidewire and endograft delivery system during endovascular aneurysm repair (EVAR). Methods Between January and May 2013, 20 consecutive patients (19 men; mean age 67.2 years, range 61–83) undergoing EVAR (n=13) or fenestrated EVAR (FEVAR, n=7) were prospectively enrolled. Each patient underwent an intraoperative contrast-enhanced cone beam computed tomography (ceCBCT) acquisition after the insertion of the endograft delivery system. Each ceCBCT was loaded on a workstation and manually registered with the preoperative computed tomographic angiogram (CTA) in a way that optimized superposition of the spine from both images. The locations of the superior mesenteric artery (SMA) and of both renal artery ostia were depicted in 3D multiplanar reconstructions by 3 independent operators on the CTA and on the ceCBCT. Motion of the aortic segment at the level of the visceral arteries was estimated by the barycenter of the origin of the SMA and both renal arteries. Results The ostium displacement between the CTA and ceCBCT images was 6.7 mm (range 2.2–13.5) for the SMA; 6.2 mm (2.5–13.5) and 6.4 mm (1.9–14.5) for the right and the left renal arteries, respectively; and 5.5 mm (2.3–11.4) for the aortic segment. The displacement was mostly posterosuperior and to the left (65%). The radiation dose and contrast volume required to perform the ceCBCT were 30% and 41%, respectively, of the amounts used in the EVAR procedures. Conclusion This study demonstrates a significant displacement of the main aortic branches after rigid material insertion. Image fusion applications aimed at providing intraoperative guidance must allow an easy and rapid repositioning of the overlay during the procedure to match the deformation of the aortic anatomy during the procedure.

Benefits of Completion 3D Angiography Associated with Contrast Enhanced Ultrasound to Assess Technical Success after EVAR.

OBJECTIVES This study evaluated a new strategy to assess technical success after standard and complex endovascular aortic repair (EVAR), combining completion contrast enhanced cone beam computed tomography (ceCBCT) and post-operative contrast enhanced ultrasound (CEUS). METHODS Patients treated with bifurcated or fenestrated and branched endografts in the hybrid room during the study period were included. From December 2012 to July 2013, a completion angiogram (CA) was performed at the end of the procedure, and computed tomography angiography (CTA) before discharge (group 1). From October 2013 to April 2014, a completion ceCBCT was performed, followed by CEUS during the 30 day post-operative period (group 2). The rate of peri-operative events (type I or III endoleaks, kinks, occlusion of target vessels), need for additional procedures or early secondary procedures, total radiation exposure (mSv), and total volume of contrast medium injected were compared. RESULTS Seventy-nine patients were included in group 1 and 54 in group 2. Peri-operative event rates were respectively 8.9% (n = 7) and 33.3% (n = 18) (p = .001). Additional procedures were performed in seven patients (8.9%) in group 1 versus 17 (31.5%) in group 2 (p = .001). Two early secondary procedures were performed in group 2 (3.7%), and three (3.8%) in group 1 (p = .978). Median radiation exposure due to CBCT was 7 Gy cm(2) (5.25-8) (36%, 27%, and 9% of the total procedure exposure, respectively for bifurcated, fenestrated, and branched endografts). CEUS did not diagnose endoleaks or any adverse events not diagnosed by ceCBCT. Overall radiation and volume of contrast injected during the patient hospital stay in groups 1 and 2 were 34 (25.8-47.3) and 11 (5-20.5) mSv, and 184 (150-240) and 91 (70-132.8) mL respectively (reduction of 68% and 50%, p < .001). CONCLUSIONS Completion ceCBCT is achievable in routine practice to assess technical success after EVAR. Strategies to evaluate technical success combining ceCBCT and CEUS can reduce total in hospital radiation exposure and contrast medium volume injection.

Total endovascular repair of an aortic arch aneurysm using an externalized transseptal guidewire technique.

Total endovascular treatment of complex ascending and arch disease remains extremely challenging with difficulties provided by the curvature of the arch, the variable anatomy of the great vessels, the proximity of the coronary ostia, potential damage to the aortic valve, and ventricle and instability during deployment. Given this background, reports of the total endovascular treatment of aortic arch are sparse. We describe one challenging case using an arch branched endograft that was safely advanced and precisely positioned into the ascending aorta using an externalized transseptal guide wire technique.

Total Endovascular Treatment of an Aortic Arch Aneurysm in a Patient with a Mechanical Aortic Valve

INTRODUCTION Endovascular repair of aortic arch aneurysms using an inner-branched device is a new treatment option for patients unfit for open surgery. There are many anatomical restrictions, such as the presence of a mechanical aortic valve that can contraindicate this complete endovascular approach. REPORT A new delivery system to overcome this issue has been developed. This new system was used to treat an aortic arch aneurysm 77 mm in diameter in a 37-year-old patient with Marfans syndrome. The patient was considered to be at major risk for open surgery because of severe respiratory insufficiency following a second sternotomy. DISCUSSION Total endovascular arch aneurysm repair is no longer contraindicated in patients with a mechanical aortic valve.