Primitive proatlantal intersegmental artery and carotid endarterectomy

Abstract

Anastomotic connections between the developing internal carotid and basilar arterial system exist in early fetal life. Rarely, these carotid-basilar anastomoses will persist into adult life unilaterally or, rarely, bilaterally. 1 A 78-year-old woman was admitted to the Vascular Surgery Division of Padua University (VSDPU). For 30 days, she had experienced focal (transischemic attacks with right-sided paresis-5 episodes) and nonfocal (syncope and multiple attacks of vertigo) cerebral symptoms. Digital subtraction angiography (DSA) confirmed a duplex scanning result showing a 85% stenosis of left carotid bifurcation and revealed a persistent proatlantal intersegmental artery (PIA), arising 2 cm from the origin of left internal carotid artery (ICA). The plaque was ulcerated and extended into the external carotid artery, ICA, and the PIA origin. The first and second tracts (V 1, V 2 ) of the left vertebral artery were not visualized. The left ICA had a 60% intracranial stenosis (A [Cover]).There was a 40% right carotid bifurcation stenosis with a 50% intracranial tandem stenotic lesion. The right vertebral artery was hypoplasic without intracranial connection with the basilar artery. Most of the cerebral posterior territory was supplied by the left PIA. Very poor connections were visualized between carotid and posterior territory circulation.The patient underwent left carotid endarterectomy according to a previously described VSDPU technique 2 (general anesthesia, continuous electroencephalogram monitoring, heparinization, routine delayed shunting, and polytetrafluoroethylene patching). Surgery planning took into account not only intraoperative routine shunt perfusion of the ICA but also the necessity of perfusion of the PIA due to the demonstration of incomplete circle of Willis. After left laterocervical incision and exposure of the common carotid artery, external carotid artery, ICA, and PIA with the no-touch technique, vessel clamping was followed by longitudinal arteriotomy. Two intraluminal balloon shunts (Pruitt-Inahara model 2000-49; LeMaitre Vascular, Inc, Burlington, Mass) were used after plaque removal. The first shunt was inserted distally into the ICA, and proximally into the common carotid artery. The second shunt was inserted distally into the PIA, and proximally into the common carotid artery. Proximal ends of both shunts were placed in contiguity inside the common carotid artery; balloons were partially inflated with a vessel loop encircling the artery to help with hemostasis (B). Ischemia time was 4 minutes for the carotid territory and 5 minutes for the posterior territory. Electroencephalogram frequency and amplitude decreased significantly after clamping and returned to normal after insertion of the shunts.Cerebrovascular symptoms disappeared after surgery and the patient had no problems during 12 months of follow-up. Patency of the ICA and PIA was assessed by duplex scanning and documented by DSA (C).This report differs from an unpublished case, also successfully operated in 1982 by the senior a...

Type I persistent proatlantal artery associated with fusiform subclavian artery aneurysm: Report of one case

“…Although some vascular variations have been described coexisting with the persistent PA, until now, we had not found a case of fusiform aneurysm of the subclavian artery with a persistent PA. The association of multiple atherosclerotic stenoses, along with persistent PA and appearance of multiple calcified atherosclerotic plaques, is consistent with data found in the literature 5,8,12 . The extremely calcifications of both CCA that were present in our case have not been described in recent publications.…”

“…The extremely calcifications of both CCA that were present in our case have not been described in recent publications. The unfortunate outcome of our patient, sadly confirmed that our early aggressive approach towards a surgical management, fearing that a persistent PA could be a source of further complications for the surgeon performing carotid endarterectomy, was right 8,12 . The absence of one or both VA provides an important clue in the diagnosis of persistent fetal vascular communication between carotid and vertebrobasilar arteries.…”

Internal carotid and ipsilateral type II proatlantal artery stenoses causing simultaneous hemispheric and vertebrobasilar transient ischemia

“…The use of a shunt was anatomically difficult. 10 Even if routine use of cerebral monitoring and a shunt is recommended, in our experience, high blood pressure is sufficient in most cases, especially when a complete circle of Willis coexists. 7,8,10 Some authors have reported ICA lesions with proatlantal intersegmental artery treated by an endovascular approach.…”

“…10 Even if routine use of cerebral monitoring and a shunt is recommended, in our experience, high blood pressure is sufficient in most cases, especially when a complete circle of Willis coexists. 7,8,10 Some authors have reported ICA lesions with proatlantal intersegmental artery treated by an endovascular approach. 11,12 We found that this was not a good indication due to the high embolic risk with these symptomatic lesions during the catheterism or the ICA stenting covering the ECA.…”

“…[7][8][9][10] This case is particularly technically challenging because of two-staged stenosis. The use of a shunt was anatomically difficult.…”