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The exclusion of abdominal aortic aneurysms by endovascular techniques has enabled the treatment of patients who have high-risk comorbidities that preclude safe surgical repair. Since the development of the unibody bifurcated endovascular stent-graft for abdominal aortic aneurysm exclusion, remarkable technological improvements have facilitated stent-graft delivery and reduced the required size of the access site. Our initial institutional experience with the use of the Endologix IntuiTrak® Express Delivery System for the Powerlink stent-graft (in 7 patients) shows that the device is suited for percutaneous use without sequelae. Herein, we describe the IntuiTrak system and the successful results of its use: we achieved percutaneous access and closure in all 7 patients, with no conversions to open repair or vascular exposure.
The endovascular exclusion of abdominal aortic aneurysms (AAAs) has enabled the treatment of patients who have high-risk comorbidities that preclude safe surgical repair.1,2 Since the introduction of the Powerlink unibody bifurcated endovascular graft (Endologix, Inc.; Irvine, Calif),3 the delivery system has undergone substantial improvement that facilitates its deliverability and deployment for the endovascular aneurysm repair (EVAR) of AAAs.
The initial Powerlink stent-graft delivery system was approved for commercial use in the United States in 2004. The Powerlink endograft consists of a unibody cobalt chromium-alloy endostent that is sewn to the ends of a low-porosity, expanded-polytetrafluoroethylene (ePTFE) graft material. This design prevents device fatigue and erosion and allows the graft material to “float” in the aneurysmal portions of the aorta. In 2008, the Powerlink line of stent-grafts was updated to include a suprarenal-orientation design and to incorporate larger stent-graft sizes—enabling the treatment of aortic necks of up to 32 mm in diameter and iliac arteries of up to 23 mm in diameter. Currently, the Powerlink line has an integrated introducer sheath size of 19F—the smallest commercially available in the United States—for the delivery of the XL aortic extension that is 34 mm in diameter.
Using a unibody delivery system precludes the need of a 2nd large-bore access site for delivery of the contralateral iliac limb in patients who have marked tortuosity or severe vascular disease in 1 iliac artery—a situation in which large sheaths can be occlusive. The unibody design affords the unique advantages of anatomic fixation: the deployed graft rests upon the aortoiliac bifurcation, which prevents distal migration and reduces excessive stress on the stent-graft.4 Six-year data from the Endologix clinical trial have revealed excellent long-term results of EVAR with use of the Powerlink endovascular graft.5
Our center participated in a limited-release registry of the IntuiTrak® Delivery System (Endologix). The purpose of the registry was to evaluate the new IntuiTrak delivery system for possible clinical validation in percutaneous endovascular aneurysm repair (PEVAR). Here, we describe the IntuiTrak system and the results of its use in 7 patients.
Patients. Beginning in November 2008, we performed PEVAR in 7 consecutive IntuiTrak registry patients, using the techniques described below. Table I shows the preprocedural characteristics of the patients. All 7 presented with calcified or tortuous iliac arteries, which in our experience presents a moderate-to-severe degree of difficulty for access. Indeed, before PEVAR, 1 patient with iliac stenosis required iliac angioplasty to facilitate device introduction, and 1 patient with a common iliac artery aneurysm required embolization of the hypogastric artery.
Materials. The IntuiTrak Delivery System (Fig. 1A) is substantially improved technologically over previous systems that deliver the endograph via a totally percutaneous approach. The Powerlink device is housed in a delivery system that has a 19F, hydrophilically coated introducer sheath (outer diameter, 21F) and a hemostasis valve with a control cord-deployment mechanism. A docking port and cartridge enable the delivery of any necessary aortic or iliac extensions up to 34 mm in diameter through the indwelling introducer sheath (Fig. 1B).
Another feature of the IntuiTrak is SurePass™ precannulated contralateral-limb technology (Endologix). This technology enables the passage of a 0.014-in guidewire to maintain access through the contralateral iliac limb. In addition, because the body of the stent-graft can be delivered via 1 main iliac artery, an access size of only 9F is needed in the contralateral femoral artery.
Techniques. All 7 patients underwent the procedure under local anesthesia and with the use of conscious sedation. We performed EVAR via percutaneous access (Fig. 2) and closure, with use of the Prostar XL® (Abbott Vascular, part of Abbott Laboratories, Inc.; Abbott Park, Ill) in a “pre-close” fashion.6
We achieved successful percutaneous access and closure in all 7 patients, with no conversions to open repair or vascular exposure (Table I). We observed no hematomas, pseudoaneurysms, or other sequelae associated with the procedure, and all patients were discharged from the hospital the next day. A notable example is the case of a 75-year-old man who had hypertension, coronary artery disease, renal failure, chronic obstructive pulmonary disease, and an enlarging AAA upon aortography (Fig. 3A). Despite substantial tortuosity of the iliac artery, the aneurysm was successfully excluded (Fig. 3B). Of particular relevance to PEVAR, all 7 patient's ankle–brachial indices before the procedure and at 1-month follow-up showed no significant change.
By simplifying access and deployment, the IntuiTrak delivery system enables a bilateral percutaneous approach for delivery of the Powerlink XL unibody stent-graft. We conclude that use of the IntuiTrak in PEVAR decreases the number of sequelae and leads to excellent procedural outcomes. Although our preliminary experience in performing PEVAR with the IntuiTrak system is positive in comparison with our use of all previous devices, we look forward to clinical validation in the upcoming multicenter, randomized PEVAR trial.
Address for reprints: Zvonimir Krajcer, MD, 6624 Fannin St., Suite 2780, Houston, TX 77030
Dr. Krajcer serves as a consultant and on the speakers' bureaus for W.L. Gore & Associates and Endologix, Inc. He is a clinical investigator in the Aptus Endosystems, Inc.; Lombard EndoRefix; Endologix; and Aorfix trials.