The incidence of CAS is substantially high in the
elderly population as in the other peripheral artery
diseases. In the Rotterdam study, stenosis between
16 and 49% was found in 3% of patients over the
age of 55 years, and stenosis over 50% was found in
1.4%.[
9] Similarly, in the Tromso study, the prevalence
of CAS in men over the age of 50 years was found
to be 4.2, while it was 2.7% in women, indicating
a statistically significant difference between the
sexes.[
10] In the Framingham study, in 40% of
75-year-old men, a narrowing of more than 10% was
found.[
11] The disease, which is very widespread in the
elderly, has a high cost to the society, the individual,
and the environment. Considering the monetary cost,
the total annual cost of stroke in the United States is
estimated as $ 65.5 billion.[
12] The total annual cost
of stroke in the Europe is estimated as € 27 billion.[
12]
Carotid artery disease is the cause of an average of
20% of these strokes.
The necessity of the CEA method in advanced
CAS, its priority over other treatment modalities, and
the variety of surgical techniques applied urge us to
find the most ideal surgical method. Before starting
CEA, it is necessary to decide the anesthesia type of the
operation. The randomized Local Anesthesia versus
General Anesthesia for Carotid Surgery (GALA) study showed no significant difference between the
general (4.8%) and local (4.5%) anesthesia in terms
of intraoperative mortality, stroke or myocardial
infarction.[13] In our clinic, general anesthesia method
is routinely used. Since the arteriotomy performed in
classical CEA includes CCA and ICA and the wide
area can be reached in the CEA procedure, there
is no problem in accessing the distal and proximal
ends. However, there may be problems in finding
the correct plane during the CEA procedure. The
plaque may rupture in pieces rather than as a whole,
leading to weakening of the vessel wall in some areas,
remaining plaque remnants in some areas, and forming
a rough surface. After CEA is completed, when it
comes to the closure stage, it may be necessary to use
a native or synthetic patch in some cases, as the lumen
may narrow, while performing primary repair. The
Cochrane database review focused on seven studies.[14]
The results of 1,127 patients and 1,307 operations
were examined, and the results of primary repair, vein
grafts, and other grafts were analyzed. Although the
data in the analyzed studies were insufficient and
included methodological errors, the results obtained
from the examined studies concluded that the risk of
stroke was lower in the patch plasty group compared
to the primary repair group, and arterial occlusion was
lower in the patch plasty group in long-term follow-up.
However, unlike retrospective analyses, randomized
clinical studies revealed no statistically significant
difference between these groups. Nevertheless,
the evidence obtained is that the application of
carotid patch plasty reduces the risk of occlusion and
restenosis, as well as the combined stroke and mortality
rate.[15] Considering the results of the materials used in
patch plasty (Dacron®, polytetrafluoroethylene, or
autologous), the difference between them was found
to be small.[16,17] In our patient groups, there was no
statistically significant difference in terms of the use
of patches in either group. However, patches were not
used in patients who developed mortality, morbidity,
and late restenosis. In the eversion technique, when
the ICA is completely transected from the bifurcation,
the plaque is everted and removed from the ICA
during CEA. Thus, no more tissue remains in the
vessel wall, although problems may occur in reaching
the proximal end point of the CCA and the distal end
of the ECA. While the ICA is fully transected from
the bifurcation, there is a possibility that adjacent
nerves, particularly the Vagus nerve, can be damaged.
In this method, the proximal mouth of the ICA is
enlarged and sutured again to the bifurcation point and, thus, it does not cause any surgical stenosis in
the vessel lumen. In the Cochrane study, the eversion
technique caused less restenosis than other techniques,
the results obtained from other studies were similar,
and no significant difference was observed in terms of
neurological deficits between the eversion technique
and classical CEA techniques.[18,19]
Although shunts are not used in the eversion
technique, some surgeons have advocated the use
of shunts, particularly in patients with an occluded
contralateral carotid artery.[20] In the randomized
International Carotid Stenting Study (ICSS) study,
patients who underwent CAE and carotid stenting
were applied diffusion-weighted magnetic resonance
imaging to evaluate postoperative early (one to
three days) acute ischemia, while fluid-attenuated
inversion recovery investigation was conducted to
evaluate late (four to six weeks) permanent brain
damage.[21] Percentages of new ischemic events in
the patients with early carotid stenting and in
patients who underwent CAE were 46.4% and
14.1%, respectively. Most of the patients remained
asymptomatic. In the late period, permanent cerebral
abnormalities were detected to be 30% in the carotid
stenting group and 8% in the CEA group.[22] Based
on these results, it should be kept in mind that
any further manipulation into the ICA may have
more negative consequences than expected. In the
European Carotid Surgery Trial (ECST) involving
1,729 patients, no statistically significantly positive
results were found in terms of the use of shunts.[23] On
the other hand, controlling the adequacy of cerebral
perfusion with any non-invasive methods before
deciding to use a shunt may prevent unnecessary
usages. In the study of Ozer and Ceyran,[24] cerebral
perfusion could be non-invasively determined using
near infrared spectroscopy. Continuous measurement
of cerebral oxygenation can be achieved by cerebral
oximeter and more than 20% decrease compared
to baseline levels shows a troublesome at cerebral
perfusion. Conversely, preserved cerebral oxygen
saturations after clamping carotid artery may give an
insight that the adequacy of cerebral perfusion. Thus,
unnecessary usage of shunts may be restricted.
In the MEE technique applied in our center,
since, in an ideal plane, CEA was performed in the
media adventitia junction and as a complete block
(CCA, ECA and ICA complete), there were no cases
such as thinning of the vessel wall and tissue debris in
the wall. The time of procedure was not long, as the method was practical and no extra-intervention (such
as plate fixation or shunt placement) was applied.
Of note, in the MEE method, cross-clamp time was
shorter than classical CEA, consistent with previous
studies.[25]
The main limitations to the present study are its
retrospective nature with a relatively small sample size,
the lack of mid- and long-term follow-up data, and
lack of routine intraoperative monitoring of cerebral
perfusion.
In conclusion, CEA is the primary treatment
option in the light of available data in advanced CAS.
Different techniques are used in this treatment. In
our clinic, classical CEA and MEE are successfully
applied as carotid artery surgery. In our study, we
found no statistically significant difference between
the two methods in terms of intraoperative mortality,
morbidity, and restenosis rates. Based on these results,
we suggest that the MEE applied in our clinic is
as effective as classical CEA. We believe that this
method should be kept in mind as an alternative to the
classical CEA technique.
Declaration of conflicting interests
The authors declared no conflicts of interest with respect
to the authorship and/or publication of this article.
Funding
The authors received no financial support for the research
and/or authorship of this article.