S.V. Volkov, G.I. Antonov, V.A. Lazarev, V.A. Ivanov, E.R. Miklashevich
(Vishnevsky Central Military Clinical Hospital, Krasnogorsk;
Faculty of Neurosurgery of the Russian Medical Academy of Postgraduate Education, Moscow)
There were 33 cases, subject to 35 endovascular interventions in the departments of neurovascular and endovascular surgery of the Vishnevsky Central Military Clinical Hospital. They were performed on subclavian arteries (20, 57.1%), a brachycephalic trunk (5, 14.3%), internal carotid arteries (8, 22.9%) and vertebral arteries (2, 5.7%). A mean age of cases was 60 years (24-74 years).
Estimation of stenotic lesions was carried out with duplex scanning, angiography and intravascular ultrasonic examination.
Anamnesis of 12 cases (34.3%) was indicative of stroke or episodes of transient disorders of cerebral circulation. Several patients (28.6%) had a clinical picture of multifocal atherosclerosis. Blood pressure, measured on the right and left hands of cases with stenosis of subclavian arteries (SCA), was different in 90% of them.
Self-expanding nitinol stents were implanted to all the cases with lesions of internal carotid arteries (ICA). It was performed against a background of protecting cerebral vessels from embolism, caused by microparticles. Transcranial Doppler was used for intraoperative control of stenting in 50% of cases. As for lesions of subclavian arteries, stenting and balloon angioplasty were used in 17 (85%) and 3 (15%) cases respectively. Stenosis of subclavian arteries was usually localized in proximal segments (90%) and accompanied by syndrome of vertebral-subclavian steal. These circumstances prevented embolism of cerebral vessels in balloon dilation, as blood flow reversion in a vertebral artery took place after a definite period of time (45-60 sec), following restoration of the SCA lumen. Angioplasty with a positive direct result was made in 2 cases with lesions of vertebral arteries.
Patients with lesions of a brachycephalic trunk underwent direct stenting with compression of a common carotid artery during stent dilation.
All the cases with stents, implanted into the ICA, were subject to X-ray examination 7-14 days after operation. It was carried out in an area of stent implantation for estimation of its complete and uniform opening, which was achieved in all the cases. Stenting of a subclavian artery was accompanied by detachment of a tip of a delivering catheter (the SMART system) in 1 case. It demanded additional efforts, aimed at removal of the torn-off fragment. Stenting of the ICA was a cause of intraoperative transient disorders of cerebral circulation in 2 cases (5.7%). They were cut off with the help of drug therapy. Additional dilation of a stent, implanted into the right ICA, resulted in its rupture below the stent and paravasal penetration of a contrast substance in 1 case (2.8%). Bleeding was arrested by partial digital compression of the common carotid artery. One could watch no angiographic signs of the contrast substance penetration beyond the limits of a vascular bed 20 min later. There were no fatal outcomes.
According to our experience, balloon angioplasty and stenting of brachycephalic arteries are little-traumatic and rather effective methods. They can be an alternative of surgical treatment in the majority of patients. Stenting should be a method of choice in cases with severe accompanying pathology. Angioplasty and stenting of carotid arteries demand brain protection. Dilation of a brachycephalic trunk is safe and possible but only under conditions of adequate blood flow in the left ICA. Operations should be performed by experienced and well-trained specialists.