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.