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Vision of optimal vascular surgical training in the next two decades: Strategies for adapting to new technologies

1996; Elsevier BV; Volume: 23; Issue: 5 Linguagem: Inglês

10.1016/s0741-5214(96)70259-8

1097-6809

Wesley S. Moore, G Clagett, R W Hobson, J B Towne, Frank J. Veith,

Vascular Procedures and Complications

The invasive treatment of patients with the va-riety of vascular disorders is a dynamic discipline. It has undergone rapid development and has provided highly satisfactory therapeutic solutions to a large number of clinical problems that had been previously thought to be insoluble. Introduction of less-invasive techniques, however, will undergo rapid evolution and change. Teaching programs must recognize and respond to this changing environment to provide optimal contemporary training and experience for future practitioners. A training program must lead, not follow, to best serve the needs of the profession and the public that it serves. Vascular surgeons have traditionally led the way in the diagnosis and treatment of patients with vascular disorders. Vascular surgery involvement began with the introduction of contrast angiography by Brooks in 1924 and continued with well-recognized surgical approaches for the management of vascular disorders. These included such techniques as endarterectomy, bypass, and replacement grafting for arterial occlusive and aneurysmal disease. In a similar fashion, vascular surgery has developed and applied techniques for the management of superficial and deep venous disease and the management of disorders of the lymphatic system. In many countries, particularly in the United States, the vascular surgeon has also assumed the role of vascular physician and diagnostician. Important exceptions to this practice existed in such programs as the Mayo Clinic, which had and still has an identifiable program in vascular medicine. Nonetheless, the development of noninvasive diagnosis was pioneered by vascular surgeons, and its use was applied to the diagnosis of patients with vascular disease. Vascular surgeons have also been called on to exercise not only their diagnostic skills, but also their judgement in determining whether a patient may be best served by a nonoperative or an interventional approach for a specific disorder. For example, patients with intermittent claudication traditionally undergo a careful history, physical examination, and noninvasive diagnosis to establish the anatomic location and the physiologic limitation of a specific lesion. Conservative measures, such as an exercise program, risk-factor modification, and pharmacologic therapy are initially advised. A failure of these conservative methods of management from the patient's perspective and functional needs would then, and only then, serve as a basis for interventional or surgical repair. Thus in many instances, the vascular surgeon currently serves in the capacity of a vascular disease specialist and provides the comprehensive care of patients with vascular disorders. As the vascular surgeon/vascular disease specialist became busier with the day-to-day management of patients, including vascular surgery, it became apparent that the performance of contrast angiography was occupying a large proportion of the specialist's time. Members of departments of radiology began to express an interest in becoming directly involved with the performance of angiography along with the traditional role that they served for official angiographic interpretation. Many busy vascular surgeons were only too happy to turn over the performance of angiography to their radiologic colleagues. First, it freed up their time to become more involved in direct patient care, including surgery, and second, it was recognized that an individual who specialized in performing angiography would, in the long run, be more likely to produce better diagnostic results and would have the time and interest to advance technical development in the specialty. This clearly occurred. Older vascular surgeons will remember the days of translumbar aortography combined with primitive methods of film exchange by hand. A vascular surgeon from a previous generation, caught in a time warp and suddenly placed in a modern angiography suite, would be thoroughly amazed with the advances achieved with catheter-directed arteriography, sophisticated timing devices, film-changing technology, digital imaging, and all of the other technologic advances that are widely used in current angiographic practice. The interval from the mid-1960s to the late 1970s was a golden era in the spirit of a collaborative relationship that existed between vascular surgery and radiology, each bringing their unique skills to bear on the diagnosis and management of patients with vascular disease. Each specialty had a clearly defined role with complementary, and not conflicting, interests. With the introduction of catheter-based invasive angiography to the specialty of radiology, the character or personality of the individuals who entered radiology as a specialty career underwent change. Bright and aggressive individuals began to explore the potential for therapeutic intervention with catheter-based technology. Such pioneers as Dotter and Gruntzig adapted guidewire and catheter techniques to develop endoluminal angioplasty as a means of improving blood flow through diseased segments of an affected artery. The success of these and subsequent programs changed the role of the radiologist and has affected the relationship between vascular surgery and what has now been called interventional radiology. With the development of interventional radiology and expansion of the techniques that can be applied through percutaneous catheter-based technology, a more troubled coexistence has begun to emerge. This threatens the previous collegial relationship that existed between vascular surgery and radiology. The additional interest of interventional cardiologists to treat other vessels in addition to coronary arteries has further increased the potential for a destructive conflict. The vascular surgeon recognizes that more of his patients who would have ordinarily been treated by conventional vascular repair are being managed by interventional radiologic techniques. Examples include the metamorphosis from aortofemoral bypass grafting for iliac disease to balloon angioplasty, with or without the adjunctive use of stents. Renal angioplasty has become a substitute, in many instances, for renal artery bypass. Thrombolytic therapy has become a successful substitute for balloon catheter thromboembolectomy. Emergency portal decompression operations have been replaced by transjugular intrahepatic portosystemic shunt procedures. The list continues. The conflict or troubled competitive coexistence between vascular surgery and the catheter-based interventional specialties becomes even more critical with the introduction of the newer stent technologies, and in particular the possibility of introducing vascular grafts into the aortoiliac and other peripheral arterial beds with catheter-based delivery systems for the treatment of aneurysmal, occlusive, and traumatic arterial lesions. Early prototypes, currently under clinical investigation, require a combination of traditional surgical skills and guidewire and catheter-based skills. In many instances, surgeons have seen this as an opportunity to reclaim the initiative to control the development and application of these newer techniques. Interventional radiologists are concerned that they may be shut out or placed in a secondary role in patient management. If the new technologies are effective and durable, they will clearly replace a large number of procedures that previously were only treatable with open surgery. Although this change may be of great benefit to the patient with vascular disease, the question arises as to how we can best train future generations of specialists to apply these new technologic advances. The application, for example, of endovascular graft repair of abdominal aortic aneurysm requires a combination of surgical skill, catheter skill, and fluoroscopic imaging skill. Neither vascular surgery nor interventional radiology training programs currently offer their trainees instruction in all the skills that are required to perform these new endovascular grafting procedures optimally. Although the importance of vascular surgeons gaining catheter-guidewire imaging skills has been brought into focus by the introduction of stented-graft techniques for the repair of aortic aneurysms, there are many other reasons why these skills should be among those possessed by vascular surgeons.1Veith FJ. Transluminally placed endovascular stented grafts and their impact on vascular surgery.J Vasc Surg. 1994; 20: 855-860Abstract Full Text Full Text PDF PubMed Scopus (42) Google Scholar, 2Veith FJ Marin ML. Endovascular surgery and its effect on the relationship between vascular surgery and radiology.J Endovasc Surg. 1995; 2: 1-7Crossref PubMed Scopus (15) Google Scholar Endovascular grafts may prove to be superior to standard surgically placed prosthetic grafts in the treatment of other aneurysmal lesions along with traumatic and occlusive arterial lesions.3Parodi JC Palmaz JC Barone HD. Transfemoral intraluminal graft implantation for abdominal aortic aneurysms.Ann Vasc Surg. 1991; 5: 491-499Abstract Full Text PDF PubMed Scopus (2797) Google Scholar, 4Moore WS Vescera CL. Repair of abdominal aortic aneurysm by transfemoral endovascular graft placement.Ann Surg. 1994; 220: 331-341Crossref PubMed Scopus (155) Google Scholar, 5Moore WS. The role of endovascular grafting technique in the treatment of infrarenal abdominal aortic aneurysm.Cardiovascular Surgery. 1995; 3: 109-114Crossref PubMed Scopus (17) Google Scholar, 6Moore WS Rutherford RB for the EVT Investigators Transfemoral endovascular repair of abdominal aortic aneurysm: Results of the North American EVT phase I trial.J Vasc Surg. 1996; 23: 543-553Abstract Full Text PDF PubMed Scopus (336) Google Scholar, 7Marin ML Veith FJ Panetta TF et al.Transluminally placed endovascular stented graft repair for arterial trauma.J Vasc Surg. 1994; 20: 466-473Abstract Full Text Full Text PDF PubMed Scopus (270) Google Scholar, 8May J White G Waugh R Yu W Harris J. Transluminal placement of a prosthetic graft-stent device for treatment of subclavian artery aneurysm.J Vasc Surg. 1993; 18: 1056-1059Abstract Full Text Full Text PDF PubMed Scopus (136) Google Scholar, 9Marin ML Veith FJ Cynamon J et al.Transfemoral endovascular stented graft treatment of aortoiliac and femoropopliteal occlusive disease for limb salvage.Am J Surg. 1994; 168: 156-162Abstract Full Text PDF PubMed Scopus (80) Google Scholar In addition, endovascular procedures such as balloon angioplasty and stent placement have already been shown to be valuable adjuncts to vascular surgical bypass operations when unexpected inflow or outflow lesions are detected. These endovascular adjuncts, which obviously require catheter-guidewire imaging skills to perform, are simpler than purely surgical alternatives and are probably best performed in the operating room as part of the overall operative procedure. Moreover, in some instances in which combined segment arterial disease is being treated at a single sitting, it may prove advisable to plan to treat one segmental part of the disease endovascularly while another segment is being treated by a standard surgical bypass.10Marin ML Veith FJ Sanchez LA et al.Endovascular aortoiliac grafts in combination with standard infrainguinal arterial bypasses in the management of limb-threatening ischemia: preliminary report.J Vasc Surg. 1995; 22: 316-325Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar Finally, standard vascular procedures may be simplified or improved by the use of catheter-guidewire imaging techniques. This has already proven to be the case with fluoroscopically assisted thromboembolectomy, in which passage of balloon catheters is facilitated and arterial damage lessened by the availability of these endovascular techniques.11Parsons RE, Marin ML, Veith FJ, et al. Fluoroscopically assisted thromboembolectomy: an improved method for treating acute occlusions of native arteries and bypass graft. Ann Vasc Surg, in press.Google Scholar How, then, can we best respond to this technologic revolution by improving our training programs so that the new graduate will receive appropriate training, under the traditional approach of supervision, before proceeding to apply these new, potentially better, techniques to the patient population? There has been no uniform response to the challenge offered by new technology and, in particular, catheter-based technology. Several approaches have been used and can be identified. Many vascular surgeons are of the opinion that these new techniques are doomed to failure and will go the way of laser angioplasty. Their hope is that these techniques will have a short lifespan, and in the meantime they will continue to offer their traditional vascular surgery therapy. Many vascular surgeons are quick to embrace new technology and to start using it before its efficacy is proven and the techniques are fully developed. There is a tendency to believe that new equals good and a conviction that this technology is a steamroller coming down the road and that it is better to jump on it rather than becoming a part of the road. A limited number of surgeons, in academic institutions, will attempt to become involved in the investigation of new technologic devices to help determine efficacy and to be involved in their development. A number of vascular surgeons in community practice will find themselves in a setting without interested and aggressive interventional radiology. Those individuals will begin to train themselves in catheter-guidewire imaging techniques in the performance of angiography and will begin to use balloon angioplasty and stenting within the confines of their own practice. It is obvious that a number of problems are associated with all the scenarios that have been described. We will focus on two major problems. First, if the new endovascular technologies prove to be effective, failure to become involved by individual practitioners will lead to their obsolescence and exclusion. If generally applied, this failure could lead to the elimination of vascular surgery as a specialty. For example, where would the general surgeon who has failed to develop skills in laparoscopic cholecystectomy be today? Conversely, these endovascular technologies could be regarded as an opportunity. For example, urology became a distinct specialty separate from general surgery with the introduction of the cystoscope. Cardiothoracic surgery became a separate specialty with the introduction of the pump oxygenator. Second, by and large, limited or no training is available for established vascular surgeons or for trainees in vascular surgery who wish to have a comprehensive experience in catheter-based techniques. Vascular training programs offer little or no training in angiography or interventional techniques, primarily because academic institutions have parallel training programs in interventional radiology designed to train radiologists to become specialists in interventional radiology. This gap in training opportunity has led to several unsatisfactory solutions. These have included self-training, with individuals reading about the procedures, perhaps observing the work of an interventional radiologist, and then simply proceeding to develop these skills, without supervision, on his own patient population. Another approach has been to use traditional procedures currently available in training programs, such as central line placement and balloon catheter thromboembolectomy, to practice catheter-guidewire imaging skills by performing them under fluoroscopic control with the same directional catheters and guidewires that might be required in more complex interventional techniques. Another approach is to find a cooperative interventional radiology service, either in the United States or abroad, that is willing to take a vascular surgeon as a trainee. Although this has the potential of providing for a good supervised experience, no defined curriculum exists, and the time in this type of training program is often limited. The results of these attempts to obtain training and to incorporate endovascular catheter-based techniques into surgical practice are at best questionable and certainly will not be competitive with the type of training that an interventional radiologist will receive in a formal academic training program. This training is likely to lead only to limited application of otherwise well-established and effective techniques. It also may result in compromised outcome. The easiest possible solution would be to continue to abrogate any involvement on the part of vascular surgery in endovascular techniques. We would thus relinquish all claim to endovascular procedures to interventional radiology. Vascular surgery would continue to do its traditional surgery, and interventional radiology would carry out catheter-based interventional techniques. Referring physicians and patients would then be placed in the position of making a choice, and in essence, the marketplace would sort it out. The net result of this approach would probably be a diminished role for vascular surgery and vascular surgeons in the care of patients with vascular disease. Interventional radiology would continue to encroach on areas that we consider to be our strengths, including patient evaluation and management, judgement based on wide experience, and even the surgical exposure of peripheral arteries. Academic training programs could declare their intent to take back positions relinquished to radiology, including angiography. Vascular surgery programs could set up angiography suites for contrast diagnostic studies and offer more traditional invasive procedures, such as balloon angioplasty and stent placement, and then be clearly positioned for training in the newer endovascular techniques of endovascular grafting. Although this might be an appealing solution to many, it would result in an expensive duplication of resources. It would also likely result in a destructive intramural war between departments of radiology and surgery, from which no one is likely to emerge as a clear winner. A utopian solution to the problem would be a team approach in which an interventional radiologist and vascular surgeon would work together. Each would be responsible for a portion of a procedure or a part of a population of patients with vascular disease in which the open surgical procedure would be done by the vascular surgeon and the catheter portion of the procedure would be done by the interventional radiologist. This might work quite well in relatively small institutions, without a wide geographic and philosophic separation of specialties. It should be recognized, however, that such collaborative relationships often end up being one-sided, where a dominant individual from one specialty overwhelms his counterpart from the other specialty. It is also difficult to conceive how this plan would work in the context of a training program in which trainees from vascular surgery and their mentor would combine efforts with trainees from interventional radiology and their mentor. This would make for a rather crowded procedure or operating room. It is our belief that vascular surgeons and interventional radiologists have more in common with each other than they have with their respective parent departments. Furthermore, they tend to be separated more by label (surgeon, radiologist) than they do by interest, abilities, patient population, and practice. It may well be that the optimum solution for both training and practice is to recognize that we have to redefine our activities in the context of a new specialty, and hence a new department. Thus all individuals could work together within a single departmental structure in which they are bound both by their areas of interest and their economic interests. A new department would incorporate individuals with skills in open vascular repair, catheter-based vascular intervention, vascular imaging, and vascular medicine. We would need to propose a comprehensive name for such a new department. Possible names might include “Vascular Biology and Intervention,” “Vascular Disease/Disorders,” “Vascular Diagnosis and Therapy,” or “Angiology.” The department might well be divided into four divisions to include vascular medicine, vascular surgery, vascular intervention, and vascular imaging. The important and unifying factor would be a single category of trainee. The number of trainees taken into the program would be limited by the volume available in the respective activities. This would produce a trainee that has a hybrid of knowledge, experience, and technical expertise. A curriculum would need to be developed and may well require a 2- to 3-year commitment in the specialty. Rotations for varying periods of time would take place in all divisions to provide sufficient expertise for the core body of knowledge that each division would have to offer. On completion of such a residency program, the product of the training program would be a true vascular disease specialist in every sense of the word. A board examination would have to be developed that would examine the graduate of such a program in all four components of the specialty. On successful passing of examination, an individual would be certified as a specialist in vascular disease. On leaving the training program, graduates would then be free to set up a practice in which they could practice any or all components of their specialty training. In the case of large institutions or academic medical centers, it would be appropriate for an individual to limit his or her practice and area of expertise to one of the four components, but having been trained in all four, that individual would be not only more expert, but could also cross-over where appropriate. Initially, such an academic department would draw their faculty from four different disciplines. Interventional radiologists, having left their parent department of radiology, would staff the division of vascular intervention; vascular surgeons, having left their parent department of surgery, would staff a division devoted to open vascular repair; individuals from internal medicine and cardiology who have an interest in vascular disease would staff a division of vascular medicine; and faculty with a particular interest in vascular imaging using the methods of radiation or ultrasound would staff a division of vascular imaging. Future faculty appointments would come from the cadre of new trainees that elect to concentrate their effort in one of the four disciplines. In the meantime, specialists who have left their previous departmental relationships must be provided with assurance that they will maintain academic and financial parity as well as an equal role in the governance of a new department. One model for the governance of this department might be as follows: each specialty division would have its own chief. The department will be governed by an executive committee made up of the division chiefs, with the chairman drawn from the ranks of division chiefs and serving for a specific term on a rotational basis. Although the optimum solution, in our opinion, would be a newly organized department, it is unlikely that this will happen quickly. Therefore, an interim solution or a phase-in is needed for implementation of this concept. This phase-in would involve both the issues of specialty realignment and modification of existing training programs. Currently, a number of institutions have established vascular disease centers. The vascular disease center is meant to be a multispecialty, interdisciplinary program in which various specialists interested in patients with vascular disorders work together to optimize management of patients referred to the center. This clearly will be an important first step before proceeding to formal realignment and departmental status. The phase-in for training would be a bit more cumbersome in that it continues to be a two-track system, one for surgeons and one for interventionists. In a new departmental reorganization, the two-track system would disappear and leave a single category of trainee. Until that occurs, however, modifications of the existing two-track system are both necessary and desirable. From the perspective of the individual finishing a 1-year program in clinical vascular surgery, arrangements could be made to spend an additional 6 to 12 months as a fellow in interventional radiology. Likewise, fellows in interventional radiology could arrange to spend time on a vascular surgery service learning basic elements of patient care and participating, at an assistant resident level, during the conduct of open vascular surgery operations. This initial hybridization of the training program could serve as a temporary bridge while the difficulties involved with reorganization into a new department could be sorted out. An interim solution for established practitioners is more difficult. One approach is for an established vascular surgeon to set up a close collaborative relationship with an interventional radiologist in a community hospital practice. Limited cross-training could take place between the two individuals, and this might best happen in an economic and practice partnership or a group practice. Another approach would be for the vascular surgeon to take a training sabbatical from his practice and spend a sufficient length of time with a busy interventional radiologist in either a formal or ad hoc fellowship. The development of a curriculum for training a vascular disease specialist is of critical importance and will undoubtedly be a subject of much debate and probable disagreement between vascular surgery and interventional radiology. Each of these two specialties looks at their own training pathway as the paradigm to be modified in a new program. Although much discussion will have to take place among educators who represent all four potential divisions of a new department, there should be some basic areas of general agreement. First of all, the new category of trainee must receive adequate training in vascular diagnosis, clinical evaluation, and patient care. They must receive sufficient experience, under supervision, with conventional open surgical techniques and catheter-directed interventional techniques. Some of these skills can be obtained concurrently during the vascular training program, and other areas of responsibility will occur later in the residency. It is important to optimize the curriculum to avoid duplication and to minimize time spent in training in areas of the four specialties that will have unlikely use or application in the final application. It would be our recommendation that the most economic use of the resident/trainee's time would occur with the following pathway. On graduation from medical school, an individual interested in becoming a vascular disease specialist would enter a general surgery training program. That would consist of a 4-year time block, with the fourth year being a chief resident. This is predicated on the assumption that the Residency Review Committee would identify and accept this pathway and would permit the fourth year to be considered a chief year. The background in a general surgery training program provides the trainee with the necessary skills of evaluating and managing patients with a variety of problems that they are likely to encounter in a population of patients with vascular disease. Thus the skills of history taking, physical examination, evaluation of comorbid conditions, and preoperative risk assessment are an important early pan of the curriculum. The skills required in preoperative and postoperative care are acquired early, and the technical surgical skills for the variety of surgical problems that the trainee is likely to encounter in patients with vascular disease will receive a firm base. Rotation onto a vascular disease service will also given them early experience in the diagnosis and treatment of patients with vascular disease and will also provide resident manpower to a vascular disease service. On completion of this 4 years of basic training, the trainee would then enter the next phase of residency training, which would be in the specialty of vascular disease. The duration of this phase of training will need to be a subject for discussion, but is likely to represent an additional 2 to 3 years. During this phase of training the trainee will rotate through all four divisions. The rotations will likely be on several occasions, and a structured curriculum designed by each division will result in graded experience and responsibility. Each division would be responsible for defining the essentials of their curriculum and negotiating with the other three divisions as to the time allocation and sequence of rotation. With proper planning, in a spirit of collaboration and compromise among the divisions, a training program will evolve that will produce a true vascular disease specialist who will be the product of a combined effort of all members of the faculty. A sense of identity will exist between the trainee and each of the divisions and a sense of pride of each participating division in producing a unique and high-caliber specialist.