Blandine Maurel

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.

Global experience with an inner branched arch endograft.

BACKGROUND Branched endografts are a new option to treat arch aneurysm in high-risk patients. METHODS AND RESULTS We performed a retrospective multicenter analysis of all patients with arch aneurysms treated with a new branched endograft designed with 2 inner branches to perfuse the supra aortic trunks. Thirty-eight patients were included. The median age was 71 years (range, 64-74 years). An American Society of Anesthesiologists score of 3 or 4 was reported in 89.5% (95% confidence interval [CI], 79.7-99.3) of patients. The 30-day mortality rate was 13.2% (95% CI, 2.2-24.2). Technical success was obtained in 32 patients (84.2% [95% CI, 72.4-95.9]). Early secondary procedures were performed in 4 patients (10.5% [95% CI, 0.7-20.3]). Early cerebrovascular complications were diagnosed in 6 patients (15.8% [95% CI, 4.0-27.6]), including 4 transient ischemic attacks, 1 stroke, and 1 subarachnoid hemorrhage. The median follow-up was 12 months (range, 6-12 months). During follow-up, no aneurysm-related death was detected. Secondary procedures during follow-up were performed in 3 patients (9.1% [95% CI, 0.0-19.1]), including 1 conversion to open surgery. We compared the first 10 patients (early experience group) with the subsequent 28 patients. Intraoperative complications and secondary procedures were significantly higher in the early experience group. Although not statistically significant, the early mortality was higher in the early experience group (30% [95% CI, 0.0-60.0]) versus the remainder (7.1% [95% CI, 0.0-16.9]; P=.066). Being part of the early experience group and ascending aortic diameter≥38 mm were found to be associated to higher rates of combined early mortality and neurologic complications. CONCLUSIONS Our preliminary study confirms the feasibility and safety of the endovascular repair of arch aneurysms in selected patients who may not have other conventional options. CLINICAL TRIAL REGISTRATION INFORMATION Thoracic IDE NCT00583817, FDA IDE# 000101.

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.

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.

Hemin prevents in-stent stenosis in rat and rabbit models by inducing heme-oxygenase-1

OBJECTIVE The introduction of drug-eluting stents (DES) has largely added benefit to the percutaneous coronary intervention. Questions about the long-term safety of DES have been raised, however, particularly with respect to late stent thrombosis. Research efforts are now being directed toward therapeutics that can impede smooth muscle proliferation and promote vascular healing. Emerging data suggest that heme oxygenase-1 (HO-1), an inducible oxidoreductase enzyme system, can exert cytoprotective effects on endothelial cells and limit smooth muscle cell proliferation. We assessed the ability of hemin, a potent HO-1 inducer, to reduce in-stent stenosis without compromising re-endothelialization. METHODS Rat aorta and rabbit iliac arteries were stented. Animals received ongoing treated with intraperitoneal hemin (50 mg/kg) or vehicle. At 7 to 28 days after surgery, stented arterial segments were collected and processed for histologic, electron microscopy, or protein analysis. RESULTS In both models, treatment with hemin reduced neointima growth without compromising re-endothelialization of the stented arteries. In the rat aorta, analysis of protein expression at 7 and 28 days after stenting revealed that hemin increased HO-1 expression and limited the early inflammatory, apoptotic, and proliferative cellular events that are common to in-stent stenosis. Hemin treatment decreased the expression of the Ki-67 protein and the activity of key regulators of smooth muscle cell proliferation, including p42/44, RhoA, and up-regulated the expression of cyclin-dependent kinase inhibitors. The beneficial effects of hemin were abolished in the presence of tin-protoporphyrin IX, an HO inhibitor. Finally, treatment with tricarbonylchloro(glycinato)ruthenium(II), a carbon monoxide donor, reduced in-stent stenosis in the rat aorta, suggesting that carbon monoxide, a by-product of heme degradation, might contribute to the protective effect of hemin. CONCLUSION These results suggest that HO-1 is important in limiting in-stent stenosis and can be regarded as a new therapeutic target.

Endovascular treatment of external iliac artery stenoses for claudication with systematic stenting.

The results of the endovascular treatment of external iliac artery lesions in patients with claudication are not well known. In the literature, very often, the studied populations are not homogenous (people with claudication and with acute ischemia) and the external iliac artery is not differentiated from the primary iliac artery. Moreover, systematic stenting is still debated. Our goal was to study the results of systematic stenting for atheromatous lesions of the external iliac artery in a consecutive and homogenous population of patients with claudication. From June 2000 to December 2006, 90 external iliac arteries were treated with systematic stenting for atheromatous lesions in 81 consecutive patients with claudication (74 men and 7 women, aged 62+/-12 years). Lesions were classified according to the Trans-Atlantic Intersociety Consensus (TASC). Endovascular treatment was systematically chosen for TASC A (n=40) and B (n=30) patients and patients at high surgical risk for TASC C (n=18) and D (n=2). One hundred and seven stents were placed; they were 37+/-21 mm long with a 7+/-0.6mm diameter. Clinical examination and duplex follow-up were carried out at a minimum of 3 months and at the end of the follow-up. There was a 2.2% complication rate, without any deaths (retroperitoneal hematoma). Mean follow-up was 23 months (with a 13-month median). Primary patency rate was 97% (standard error [SE] 2%) at 1 year, 90% (SE 4.6%) at 2 years, and 84% (SE 6.6%) at 3 years. Secondary patency rate was 98% (SE 1.5%) at 1 year, 93% (SE 3.9%) at 2 years, and 93% (SE 4.5%) at 3 years. Ten restenoses were detected and treated by endovascular techniques (n=6), bypass (n=2), or medication (n=2). At the end of the follow-up, the patients were asymptomatic (n=62) or presented with a moderate (n=17) or severe (n=8) claudication. A patient with hemodialysis was amputated at the metatarsal level. No significant predictive restenosis factor was discovered. However, the C or D TASC classification seemed to favor an earlier restenosis (p=0.06). In conclusion, our study demonstrates that, in a larger population than in the literature, systematic stenting on the external iliac artery gives satisfying results in patients with claudication.

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.

Renal outcomes analysis after endovascular and open aortic aneurysm repair

OBJECTIVE The purpose of this study was to compare renal outcomes (glomerular filtration rate [GFR] and renal volume) after endovascular aneurysm repair (EVAR) and open repair (OR) of abdominal aortic aneurysm (AAA). METHODS All AAA repairs performed between November 2009 and July 2011 were included in this retrospective study. Patients requiring suprarenal clamping and renal bypass or reimplantation and patients requiring fenestrated endografting were excluded from the OR and EVAR groups, respectively. All EVARs were performed with transrenal proximal fixation. Renal volume (calculated with a three-dimensional workstation) and GFR (estimated with the Modification of Diet in Renal Disease formula) were evaluated before the procedure, at 12 months after the procedure, and yearly thereafter. RESULTS The study included 90 patients (41 ORs and 49 EVARs). Both groups were comparable except for age at intervention, body mass index, smoking, peripheral arterial disease, arrhythmia, and vitamin K antagonist treatment. Median follow-up was 2.8 years for OR (2.5-2.9 years) and 3.2 years for EVAR (3.0-3.4 years). In both groups, we found a significant decrease when comparing postoperative estimated GFR with 1-year (14.4% decrease [3.8%-23.8%]; P = .002) and 3-year (12.8% decrease [3.8%-20.9%]; P = .0007) levels. In both groups, total renal volumes significantly diminished. Median preoperative total renal volume (372 cm(3) [311-349]) significantly decreased (6.7% [2.8%-10.5%]; P = .008) between 1 year and 2 years of follow-up. CONCLUSIONS Renal function impairment is similar after open and endovascular AAA repair. It is associated with a decrease in total renal volume, which seems to be an early and constant marker of postoperative renal impairment.

Development and Biological Evaluation of Inkjet Printed Drug Coatings on Intravascular Stent

Inkjet-printing technology was used to apply biodegradable and biocompatible polymeric coatings of poly(d,l-lactide) with the antiproliferative drugs simvastatin (SMV) and paclitaxel (PCX) on coronary metal stents. A piezoelectric dispenser applied coating patterns of very fine droplets (300 pL) and inkjet printing was optimized to develop uniform, accurate and reproducible coatings of high yields on the stent strut. The drug loaded polymeric coatings were assed by scanning electron microscopy (SEM), atomic force microscopy (AFM), and transition thermal microscopy (TTM) where a phase separation was observed for SMV/PLA layers while PCX showed a uniform distribution within the polymer layers. Cytocompatibility studies of PLA coatings showed excellent cell adhesion with no decrease of cell viability and proliferation. In vivo stent implantation studies showed significant intrastent restenosis (ISR) for PCX/PLA and PLA plain coatings similar to marketed Presillion (bare metal) and Cypher (drug eluting) stents. The investigation of several cytokine levels after 7 days of stent deployment showed no inflammatory response and hence no in vivo cytotoxicity related to PLA coatings. Inkjet printing can be employed as a robust coating technology for the development of drug eluting stents compared to the current conventional approaches.