The
future of vascular surgery in a rapidly changing world: quo vadis?
(Portuguese
PDF version)
Américo
Dinis da Gama1
1.
Professor, University of Lisbon; Head of the Vascular Surgery Clinic,
Hospital de Santa Maria, Lisbon.
Correspondence:
Dr. Américo Dinis da Gama
Av. das Forças Armadas, 133 Lote D 16º E
1600-081 Lisboa, Portugal
E-mail: dinisdagama@clix.pt
ABSTRACT
This
article presents an analysis of the evolution of medical specialties
with emphasis on the origin, the development and the future of vascular
surgery. The author highlights the role of driving forces - such
as economy, technology and human resources - in the origin of the
specialization process. In addition, the technological advances
that established the main changes in the vascular surgery since
the 1960s and the consequences of the mastery of these techniques
by specialists of other medical fields are presented. In his analysis
of the future of vascular surgery, the author focuses on the changes
of therapeutic specialties and the emergence of new challenges for
specialists and vascular surgeons
Key
words: vascular surgery, specialist, endovascular surgery
Palavras-chave: cirurgia vascular, especialista, cirurgia
endovascular.
J
Vasc Br 2002;1(3):175-80
INTRODUCTION
A specialty
is understood as a circumscribed area of the medical sciences, holding
specific knowledge and a particular means of action - as it can be observed
in cases as diverse as internal medicine, general surgery, anesthesiology,
microbiology, psychiatry, pathological anatomy, etc. These areas are
established around a body of knowledge, in which their principles and
scientific groundwork are laid, and they hold their own courses of action,
according to their purposes and objectives.
A clinical
specialty is defined as a more or less well delineated area of medical
knowledge and practice, which uses a particular means of action in order
to prevent, diagnose and treat disorders which are common to this particular
area.
In this
context, vascular surgery is considered a clinical and scientific discipline
concerned with the prevention, diagnosis and treatment of disorders
that affect the blood and lymphatic vessels, beyond the heart and the
central nervous system. In this sense, it is a peripheral vascular surgery,
according to some North American schools, distinct from a central vascular
surgery, concerned with the brain, in the field of neurosurgery, and
with the heart, in the domain of cardiac surgery.
SPECIALIZATION
The phenomenon
of specialization, i.e., the creation of autonomous areas of thought
and action, which has hit and fragmented contemporary medicine, is a
paradigm of the second half of the 20th century. This phenomenon probably
began after the end of World War II, and continued to develop up to
the end of the century.
Several
circumstances or driving forces (Table 1) have played, and continue
to play, a main role in the genesis of the phenomenon of specialization.
At the top of these forces is scientific knowledge, closely connected
to investigation, aiming at a more deep understanding of nature, in
order to better control it. Scientific investigation is, nowadays, supported
by large investments, which must be profitable in order to last. In
other words, this means there is a strong predisposition for investigating
only those topics that appear to be, at first sight, economically lucrative.
This attitude seriously compromises the course and destiny of scientific
investigation, to the detriment of the health needs of humankind at
large.
 Table
1 - Driving
forces involved in the genesis of specializations
The second
factor that has encouraged specialization is, unquestionably, the emergence
of new technologies, which came to assist both diagnosis and therapeutics.
In fact, most medical specialties have organized themselves around the
mastery of a technique: in the past, the discovery of the electrocardiogram
allowed for the development of cardiology, and the cystoscope, of urology;
more recently, hemodialysis has given rise to nephrology, digestive
endoscopy to gastroenterology, and extracorporeal circulation to cardiac
surgery, just to mention some of the most magnificent examples.
The third
most important driving force has emerged from the community's health
needs, along with a set of citizen's rights, contemplated by the statutes
of the welfare state. These needs are closely related to the community's
level of socioeconomic and cultural development, as well as to the efficiency
of the organizational model or models underlying the provision of healthcare
services, which are generically designated as "systems".
Finally,
the last of the powerful determinant factors of specialization concerns
the agents or human resources involved and, more specifically, their
education, professional experience and accreditation, all of which aim
at satisfying one of the greatest contemporary economic hallmarks, namely
employment - an irreplaceable source of subsistence and earning, pertaining
to the individual, but with a vast social projection.
With these
considerations, we have come to a completely different definition of
medical specialty, possibly closer to the reality of the contemporary
world: a medical specialty is, therefore, an area of activity organized
around an economy, in which market needs, investments and the investigations
it brings about play an important role, as well as costs, profits and
the benefits it provides, both at the individual and at the collective
level.
In other
words, a specialty begins to have a reason to be or to exist when the
body of scientific knowledge is in a position to satisfy market needs
through the use of technology, allowing for profitable investments,
aimed at the sick, with physicians acting as qualified agents, i.e.,
as specialists.
The dominant
action that these driving forces exerted and still exert allows the
conclusion that, currently, it is out of the scope of doctors to drive
the course and destiny of medicine and their specialization. This privilege,
which for centuries lay in the hands of the medical community, has eventually
been given to economy.
I believe
this is a preliminary explanation, which helps us understand the historical
path of some medical specialties, such as vascular surgery. Additionally,
it allows us to foresee the near future of such fields, which is the
question to which I turn now.
VASCULAR SURGERY
Once more, it was the discovery, and the subsequent almost simultaneous
development of three techniques (created by physicians) - endarterectomy,
bypass and vascular prostheses - that congregated surgeons and motivated
the autonomy of vascular surgery (Table 2), in a movement that began
in the 1960s and reached its climax in the 1970s and 1980s. Before that,
however, only arteriography and lumbar sympathectomy had the specific
identity of vascular techniques, as they were part of the diagnostic
and therapeutic tools of general surgeons.
Table
2 - The
historical course of vascular surgery
 |
|
Period
|
Technique
|
|
|
1960s
and 1970s
|
Endarterectomy,
bypass, vascular prostheses
|
|
1980s
|
Vascular
laboratory
|
|
1990s
|
Intraluminal
techniques
|
|
The 1980s
were marked and almost polarized by the introduction and clinical use
of one technology, the ultrasound, which came to help diagnosis, based
on the Doppler effect, and on the creation of the vascular laboratory.
This new technology came to completely modify diagnosis, and produced
a significant impact on the unstable balance of the already mentioned
driving forces, namely due to the large market opening that it favored.
The 1990s
were characterized by the expansion of therapeutic techniques called
minimally invasive, constituted mainly by balloon angioplasty, stents
and vascular endoprosthesis. Giving sequence to a truly revolutionary
movement, originated in the field of general surgery, the development
of minimally invasive techniques aimed at reducing to the minimum the
invasive character of surgical interventions; in this context, laparoscopic
cholecystectomy became the most significant and representative procedure.
The creation
and popularization of ultrasonography and, later, of minimally invasive
techniques gave rise to the emergence of an unusual phenomenon, which
caught vascular surgeons by surprise and whose shock waves are still
felt today: slowly and gradually, these techniques became accessible
and began to be mastered by intruders, I mean, specialists from other
areas.
In the
case of ultrasonography, radiologists began to gain control over the
diagnostic methodology of vascular ultrasound and came to euphemistically
assume the designation of imagiologist.
ENDOVASCULAR
SURGERY
The minimally
invasive techniques, commonly known as endovascular surgery, or, more
properly, endoluminal intervention, were promptly used by radiologists
and, later, by cardiologists, angiologists, vascular medicine specialists,
and even by neurologists or urologists (Table 3) to treat patients with
peripheral vascular disorders, due to their ready accessibility and
ease of use.
Table
3 - Specialists
who use endovascular surgery
Radiology,
earlier passively oriented towards diagnosis, became aggressively interventionist
and therapeutic, consecrating itself as interventional radiology.
It is unnecessary
to say that these movements generated and still generate enormous distress
and restlessness at all levels, which are expressed in turf wars that
gravitate around the main driving forces: market, investments, costs,
profitability and employment.
Several
movements of dispute and conflict of ideas were carried out by the main
agents involved, all calling out for an authentic right to property,
but aiming basically at the conquering of new markets and the protection
of inherent privileges and benefits.
Vascular
surgery was strongly shaken by such an invasion. The most pusillanimous
even began to see the extinction of specialty1-3,
once its field of action would become so empty to the benefit of interventional
radiology, cardiology, vascular medicine and even of other specialties,
such as neurology and urology.
The reactions
to this confrontation came to the point of raising a deep reflection
about the essence, the definition and the space destined for vascular
surgery on its road to extinction.2,3
The attitude of vascular surgeons towards the phenomenon of endovascular
surgery and the apportionment of their practice among specialists of
other areas were also discussed.
The most
diverse proposals were continuously being announced, tending either
to resist or to ignore the movement, to fight for survival,3
or even to adapt,4 merging with the most
enthusiastic promoters of such movement, as we have verified.5,6
An authentic
endovascular fundamentalism emerged in the United States and was quickly
spread around Europe. This movement, so typical of the North-American
culture, and patent in other areas and conducts of that society, can
be translated into the following key concepts:
•
Endovascular surgery will soon replace conventional vascular surgery;
•
Anyone who does not catch the 'train' now will be doomed to the obsolescence
of conventional surgical methods, rejected by all, beginning by the
patients themselves and ending up with hospital managers, insurance
companies and the industry.
Proposals
with a conciliatory nature, tending to appease conflicts and tensions,
began to appear. Among such proposals, the idea of creating vascular
centers 5-9 - vascular departments which
would gather, in harmony, vascular surgeons, imaging specialist, interventional
radiologists, cardiologists, and vascular medicine specialists - received
special attention.
These proposals,
in a way illusory or even utopian, had the only merit of temporarily
attenuating the tension and conflict, equally dividing market demands,
but neglecting, however, the underlying reason for this present reflection:
what is, after all, in this highly competitive context, the future of
conventional vascular surgery? Will it withstand the impact of new minimally
invasive technologies, namely the threat of endovascular surgery? Will
it need to open its field to other competitors, surely more numerous,
better equipped, with a fast learning pace and with an easy access to
patients?
VASCULAR
VERSUS ENDOVASCULAR SURGERY
These
questions, lived with anxiety and anguish by some, deserve a pondered,
objective and justified reflection, distant from the passionate spirit
that has, over the last years, fueled controversy, as well as its main
agents, who have not always analyzed it with the clear perception and
serenity that only a spiritual and temporal distance allows.
Some
data are already available for an evaluation of the impact that endovascular
surgery has had on conventional vascular surgery. Although this information
originates from one sole community (the United States),10,11
it is still of great interest and significance.
In
the year 2000, there were 12,390 North-American specialists working
on the invasive treatment of cardiovascular disorders. These professionals
were grouped as follows: 4,216 interventional cardiologists; 2,058 interventional
radiologists; 2,055 peripheral vascular surgeons; and 4,061 cardiothoracic
surgeons (Table 4).11
Table
4 - Number
of cardiovascular interventionists in the United States in 2000
|
|
Specialty
|
Number |
|
|
Interventional
cardiologists
|
4,216 |
|
Interventional
radiologists
|
2,058 |
|
Peripheral
vascular surgeons
|
2,055 |
|
Cardiothoracic
surgeons
|
4,061 |
|
Total
|
12,390 |
|
In this
group, vascular surgeons were the minority, and among them only 19%
were actively involved in endovascular procedures.12
Cardiologists (60%) and interventional radiologists (20%) widely controlled
the field of endovascular surgery, with a considerable share to be assumed
by interventional cardiology.9,11,12
The global
results of this activity could not be more surprising: despite the massive
invasion of interventional cardiac and vascular surgeons and the significant
increase of their productivity, conventional surgical activity was not
affected at all, even showing, concomitantly, a growing tendency.
In fact,
from 1993 to 1997 (Table 5), the number of interventional cardiology
procedures increased by 42.3% and, during the same period, the number
of surgeries for myocardial revascularization (coronary bypass) increased
by 23%.11 In an equal period of time, procedures
performed by interventional radiologists increased by 44.4%, while peripheral
vascular surgery experienced an increase of 21.6%.11
Table
5 - Cardiovascular
procedures performed in the United States between 1993 and 1997
|
|
Specialty
|
1993 |
1997 |
Variation |
|
|
Interventional
cardiology
|
414,194 |
589,216 |
+
42.3% |
|
Myocardial
revascularization surgery
|
312,109 |
383,788 |
+
23% |
|
Interventional
radiology
|
171,836 |
248,198 |
+
44.4% |
|
Peripheral
vascular surgery
|
514,237 |
625,413 |
+
21.6% |
|
The first
and most significant conclusion that can be drawn from the analysis
of these figures is that endovascular surgery neither affected nor did
it prove to be a fierce rival to conventional surgery, either in the
case of coronary procedures or peripheral vascular surgeries. Consequently,
the immediate impression is that endovascular surgery does not present
itself as a therapeutic alternative.
How can
this truly paradoxical conclusion be explained, if it goes against a
dominant and scientifically correct school of thought?
SELECTIVITY
AND DURABILITY
Two reasons
seem to be, ab initio, plausible and worthy of discussion: the high
selectivity and the low durability that characterize, today, endovascular
procedures.13
In fact,
endovascular surgery is indicated or effective for only a small number
of patients,7 usually those who present
the simplest cases or who are treated at an earlier stage, or in cases
in which the size or the anatomy favors the procedure, as in aneurysms,
contexts that do not belong, commonly and entirely, to the scope of
conventional surgery. Conventional procedures operate mainly on extensive
and multilevel obstructive processes, and in aneurysms of great volume
or unfavorable anatomy, in which an intraluminal intervention is impracticable
or counterproductive. In addition, endovascular surgery is frequently
directed to patients with high operative risks and who are, therefore,
out of the scope of conventional surgery. Thus, the traditional caseload
of classic vascular surgery tends to remain unaltered, as it appears
to have been the case.10,14,15
On the
other hand, the low durability of intraluminal procedures, expressed
by frequent occlusive complications or other forms of adverse reaction,
tend to hasten their failure and call for a later surgical intervention,
in a process that can be labeled late surgical conversion. This contributes
to an increase in the activity of conventional surgery, justifying how
both therapeutic approaches have shown concurrent developments, chiefly
evidenced in coronary revascularization procedures.11
The remarkable
expansions recorded in the field of intraluminal intervention, patent
not only in cardiology, but also in interventional radiology, within
this context, could only be possible at the expense of nonsurgical patients.
Thus, it seems plausible to conclude that endovascular surgery is more
of an alternative to medical treatment than an alternative to conventional
surgery of arteriopathies.15
The threat
that endovascular surgery seemed to pose to the field of activity of
traditional vascular surgery and the degree of controversy and restlessness
it caused among the vascular community ended up to be a fallacy, a true
myth. Conventional vascular surgery is not on its way to extinction
and has its near future guaranteed, as an expanding, diversified and
strongly motivating field of activity. And, last but not least, conventional
vascular surgery persists because it still fully satisfies the requirements
and demands of the main driving forces involved in the phenomenon of
specialization.
THE
FUTURE OF VASCULAR SURGERY
In the
beginning of this new millennium, the real threat against the destiny
of vascular surgery lies, in fact, not in endovascular surgery, but
mainly in the progress achieved with scientific knowledge, in the discovery
of fine-grained details of the biophysiology of the arterial wall, and
in the better understanding of its disorders. The advances in genetic
manipulation and engineering, in molecular biology, in pharmacotherapy,
as well as in the judicious use of factors that promote or inhibit cellular
growth and multiplication, will certainly become fundamental for the
prevention and control of arteriopathies, in a not so remote future,
and will dictate the definite end of invasive treatments, both in the
fields of vascular and endovascular surgery.
These therapeutic
models were and still are mere chapters in a historical process that
had to resort to mechanical interventions, since there were no other
options available, and which will be substituted, inexorably, by biological
actions. A vascular biologist7 or specialist will then take the place
of the vascular surgeon (Table 6) and vascular medicine will substitute
vascular surgery or, for the most conservative, it will simply preserve
the classic designation of angiology.
Table
6 - The
future of vascular surgery
|
|
Present
|
Future
|
|
|
Vascular
surgeon
|
Vascular
specialist or biologist
|
|
Vascular
surgery
|
Vascular
medicine or angiology
|
|
REFERENCES
1.
Gewertz BL. Presidential address: Overcoming our fear of flying -
Vascular Surgery in the next decade. J Vasc Surg 1996;23:745-8.
2.
Veith FJ. The S. Stanley Crawford Critical Issue Forum 1995: The future
of vascular surgery in a changing world. J Vasc Surg 1996;23:894-5.
3.
Veith FJ. Presidential address: Charles Darwin and vascular surgery.
J Vasc Surg 1997;25:8-18.
4.
Moore WS, Clagett GP, Hobson II RW, et al. Vision of optimal vascular
surgical training in the next two decades: Strategies for adapting
to new technologies. J Vasc Surg 1996;23:926-31.
5.
Hiatt WR, Creager MA, Cooke JP, Hirsch AT. Building a partnership
between vascular medicine and vascular surgery: a coalition for the
future of vascular care. J Vasc Surg 1996;23:918-25.
6.
Green RM. Collaboration between vascular surgeons and interventional
radiologists: reflections after two years. J Vasc Surg 2000;31:826-30.
7.
DeWeese JA, Baker JD, Ernest CB, et al. Vision of the vascular surgeons
as the vascular specialist of the future. J Vasc Surg 1996;23:896-901.
8.
Becker GJ, Katzen BT. The vascular center: a model for multidisciplinary
delivery of vascular care for the future. J Vasc Surg 1996;23:907-12.
9.
Sicard GA. El cirujano vascular en el nuevo milenio. Arch Cir Vasc
2001;10:1-4.
10.
Stanley JC, Barnes RW, Ernest CB, et al. Vascular Surgery in the United
States: workforces issues. J Vasc Surg 1996;23:172-81.
11.
Wieslander CK, Huang CC, Omura MC, Ahn SS. Endovascular workforce
for peripheral vascular disease: current and future needs. J Vasc
Surg 2002;35:1218-25.
12.
Kashyap VS, Ahn SS, Petrik PV, et al. Apprentissage et pratique actuels
de la chirurgie endovasculaire: Resultats d'une enquête. Ann
Chir Vasc 2001;15:294-305.
13.
Hallett JW. Presidential address: Back to the future of vascular surgery
- why certain procedures become obsolete. J Vasc Surg 1997;25:791-5.
14.
Arko FR, Lee A, Hill BB, et al. Impact of endovascular repair on open
aortic aneurysm surgical training. J Vasc Surg 2001;34:885-91.
15.
Dinis da Gama A. Angioplastia/stent na isquemia dos membros inferiores:
a perspectiva de um cirurgião vascular. Rev Port CCT e Vascular
1999;13/14:91-5.
|
