AAA Endografting in the Cath Lab
The requirements for this procedure remain the same wherever it is performed.
Recent advances in endovascular procedures have allowed for the successful, reduced-risk treatment of patients with various types of vascular disease. Abdominal aortic aneurysm (AAA) repair is one area that has experienced increasing endovascular treatment.
The technical skill required for endograft placement is primarily catheter-based, not surgical. These catheter/radiologic skills are only just beginning to be adequately developed in vascular surgery training programs and in the surgical community. Cardiologists, radiologists, and vascular surgeons can all deliver effective endovascular treatment of vascular disease—provided, of course, that they have completed the appropriate training and have the correct equipment at their fingertips. The environment in which the procedures are performed is also important, but perhaps to a lesser degree.
CATH LAB PROS
Just as the delivery of care for the same disease process may be successfully completed by various specialties, the ideal location for the endograft treatment of AAA may vary as well. The cardiac cath lab offers several advantages as well as some potential drawbacks. This article discusses the pros and cons of performing endografting in the cath lab (Figure 1).
In most hospitals, the cath lab is often optimally located in proximity to the ER as well as to the operating suites. The physical structure will already contain the necessary level of radiation shielding both in the walls and within the lab to protect the health care team delivering patient care. Surgical suites are not commonly constructed with ionizing radiation in mind, and shielding must be added before endovascular procedures requiring fluoroscopy can be performed.
If the cath lab is to be used for endovascular procedures, especially for AAA endograft treatment, the room should be equipped with both an adequate radiologic intensifier (measuring >12 inches in diameter), and a vascular software package that allows for digital subtraction and road mapping, among other functions. For AAA endografts, this equipment is best mounted to the ceiling so that if open surgery is necessary, the device can be moved out of the way. The cath lab will normally possess optimal radiographic tools and a configuration of monitors that allows the entire team to view images easily.
Ancillary Endografting Equipment
The modern-day cath lab will usually have the ancillary equipment that may be necessary for optimal endograft placement and nonsurgical complication management. This may include balloons, stents, snares, and wires, as well as more expensive capital items, such as intravascular ultrasound and mechanical thrombectomy units.
From a hospital’s economic point of view, utilizing a pre-existing endovascular angiographic suite would be cost effective. When not in use for AAA endografting, the space can be used for other procedures, and the cath lab personnel will need little new training. This approach also allows the hospital to take advantage of already-purchased equipment and to avoid duplication of capital expenditures.
CATH LAB CONS
Using the cath lab for AAA endograft placement also has potential drawbacks. As long as the majority of endograft placements still require an open arteriotomy, the sterile environment must not be compromised. To ensure a sterile environment in the cath lab, installation of a sophisticated air filtration system may be required.
A surgical scrub nurse and circulator, and the surgical instruments necessary for the femoral arteriotomy (as well as for a possible open conversion), will need to be present in the cath lab. An anesthesiologist and the equipment needed for general anesthesia must also be available. The use of operating room personnel and anesthesia often results in leaving an operating room vacant during an endograft procedure in the cath lab.
Due to the large size of the necessary equipment, most angiographic suites are rarely utilized for open procedures. C-arm–based, portable radiologic equipment may produce images that are of lower quality than those produced by the permanent equipment found in full-sized angiographic suites. In my experience, suboptimal equipment complicates the procedure. In addition, correct monitor placement can be very difficult. Ideally, the angiographic table should be able to tilt if there is a need for open surgical conversion.
THE MULTISPECIALTY ANSWER
My colleagues and I have developed a multispecialty approach for placing AAA stent grafts. Although this approach is cumbersome from a reimbursement standpoint, it has allowed for a short learning curve (no intraoperative open surgical conversions), with few complications. The complementary knowledge base of the high-volume surgical specialist combined with that of the high-volume endovascular specialist appears to offer the patient the best of both specialties.
We currently perform the majority of AAA endografts in our cath lab, which was specifically designed for these and other endovascular procedures, as well as cardiac procedures. The laboratory is already equipped with an operative room ventilation system, and because the space is equipped for CO2 imaging, the angiographic table can tilt if the need for open conversion should arise. Multiple use of this room saves hospital dollars by not duplicating expensive imaging equipment and guaranteeing high-volume utilization.
My colleagues and I have completed more than 150 procedures in the cath lab and there have been no cases of graft or wound infection, and no emergency open conversions have occurred. Using our multispecialty approach, we can routinely complete endovascular stent graft treatment of AAA in less than 1 hour, refuting the argument that procedure time is not reduced with endograft stenting.
REQUIREMENTS OF AAA SUITES
I do not feel that there is any universal advantage in performing endograft placement in a particular area of the hospital. Regardless of thelocation chosen to perform the endograft, several requirements are key. The personnel should be trained and familiar with both the procedure and the necessary equipment. The best imaging tools should be used, with monitor placement that allows for optimal imaging of the procedure at the lowest level of radiation exposure to both patient and personnel. The location of the suite should have quick access to the variety of common endovascular equipment, including angioplasty supplies and the gear necessary to handle potential complications. I also believe that a multispecialty approach, with a team consisting of both a surgeon and a high-volume endovascular specialist, allows for a high success rate, reduced procedure times, and minimal radiation exposure and dye loads.
Gary M. Ansel, MD, FACC, is Director of Peripheral Vascular Intervention at Midwest Research Foundation in Columbus, Ohio. Dr. Ansel may be reached at (614) 262-6772; firstname.lastname@example.org.