Discussion
There isn’t still consensus not only on the treatment, but also on the
diagnosis and detection of arterial basins concomitant asymptomatic
lesions. In 2015, the randomized trial results proving the need for CAG
before CEA were published. 426 patients in need of CEE were randomized
into two groups. 30-day results in the group who received CAG showed no
acute MI cases and zero mortality. At the same time, in the group
without coronary angiography, the 30-day acute MI frequency was 4.3%,
and the mortality rate was 0.5%. In the long-term 6-year study results
in CAG, the acute MI incidence was 1.4%, in the group without CAG –
15.7%, and the mortality rate was 0 (0%) and 2.9%, respectively
[10].
We analyzed patients who underwent the coronary and carotid arteries
revascularization from 1.07.2014 to 01.01.2021 at the Federal Center for
Cardiovascular Surgery named after S. G. Sukhanov. Of the 7,716 patients
who underwent CABG, 1,597 (20.7%) patients had BCA lesion. Moreover,
430 (5.6%) of them underwent the carotid arteries revascularization. At
the same time, out of 681 patients who received CEA and CAS(carotid
arteries stenting), 430 (63.1%) patients underwent CABG. Such a
occurrence high rate of severe coronary atherosclerosis in patients
going for the carotid arteries revascularization can be explained by the
fact that in the Federal Center for Cardiovascular Surgery named after
S. G. Sukhanov’s patients are mostly referred for coronary angiography
and the coronary arteries’ revascularization, and carotid artery damage
is detected during follow-up examination. Despite this amendment, such a
combined atherosclerosis frequent occurrence allows us to conclude that
a screening ultrasound study of the brachiocephalic arteries before
coronary revascularization and coronary angiography before intervention
on the carotid arteries is necessary.
The mechanisms underlying the increased stroke risk in CABG are
multifactorial. We shouldn’t forget that carotid artery atherosclerosis
isn’t the only ischemic stroke predictor in CABG. Aortic atheromatosis
is probably an even more significant factor. Most CABG operations are
performed using artificial circulation with cannulation and aortic
compression; even if they are performed without ABC, the aorta is often
manipulated to create proximal anastomoses. According to our research,
the epiaortic scanning use reduces mortality by 5 times, and the stroke
risk is reduced by 12 times [11]. It is necessary to perform an
epiaortic scan on a routine basis at each operation, even without ABC.
When detecting aortic atheromatosis, the surgeon must have the full
revascularization range techniques and choose the appropriate one. It is
important to remember about the hybrid revascularization possibility to
minimize manipulations on the aorta with severe atheromatosis. In our
study, operations were performed both with and without ABC, and when
detecting the aorta atheromatosis, the changing the place of cannulation
methods, ”single clamp”, ”no touch aorta” and hybrid revascularization
were used. We assume that routine epiaortic scanning is one of the
factors for obtaining satisfactory results at the hospital stage.
To prevent intraoperative brain desaturation associated with ischemic
complications, continuous monitoring using near-infrared spectroscopy is
recommended [12]. Neuromonitoring allows to change the surgery
strategy with a significant drop in cerebral saturation and reduce the
carotid arteries compression time, thereby preventing ischemic damage.
But stable brain oximetry indicators are also important. Most surgeons
try to minimize the carotid arteries compression time, thereby reducing
the ischemia time. Sometimes this can lead to incomplete endarterectomy
with fixed plaque particles remnants in the lumen. Stable
neuromonitoring indicators allow the surgeon to work calmly without
undue haste and perform endarterectomy as fully as possible with the all
fixed and floating plaque particles removal without ischemic damage fear
due to long carotid arteries compression. The cerebral damage mechanism
after cardiac surgery with the artificial circulation use hasn’t yet
been fully studied. Pathogenesis may include embolization or
hypoperfusion causing cerebral ischemia. Cerebral oximetry monitoring is
necessary when performing CABG in patients with combined carotid artery
disease. This makes it possible to prevent ischemia both in ABC and when
performing surgery without artificial circulation, in which the heart is
positioned with hypotension periods. In this study, we used cerebral
oximetry in all operations.
To date, there are a significant strategies number and algorithms for
choosing treatment tactics for patients with the coronary and carotid
arteries combined atherosclerotic lesions. In 2020, the results of a
major meta-analysis were published. This meta-analysis included eleven
studies with a total of 44,895 patients (21,710 in the combined group
and 23,185 patients in the phased group). In the simultaneous CEA and
CABG group, there was a statistically significantly lower MI risk and a
higher stroke and death risk. The TIA frequency, postoperative bleeding,
and pulmonary complications were the same between the two groups
[13]. According to the our study results, the complications risks in
staged and combined operations with a differentiated approach to the
treatment tactics choice are comparable.