Impact of contralateral carotid or vertebral artery occlusion in patients undergoing carotid endarterectomy or carotid artery stenting Shin-Seok Yang, MD,a Young-Wook Kim, MD, PhD,a Dong-Ik Kim, MD, PhD,a Keon-ha Kim, MD, PhD,b Pyoung Jeon, MD, PhD,b Gyeong-Moon Kim, MD, PhD,c Chin-Sang Chung, MD, PhD,c and Kwang-Ho Lee, MD, PhD,c Seoul, South Korea Objective: To determine the impact of contralateral carotid occlusion (CCO) and/or vertebral artery occlusion (VAO) on the development of early postoperative neurologic complications after carotid endarterectomy (CEA) or carotid artery stenting (CAS). Methods: A retrospective analysis was conducted using a database of patients who underwent CEA (n [ 698) or CAS (n [ 455) at a single institution. Excluded were 44 CEAs synchronously performed with coronary artery bypass grafting and 76 CASs performed without an embolic protective device (n [ 69) or that resulted in technical failures (n [ 7). All CEAs were the conventional type and performed under general anesthesia, and carotid shunts were routinely used. Patients were categorized into three groups according to patency of the contralateral carotid and vertebral arteries: Group I (no CCO or VAO); Group II (CCO with or without VAO); Group III (with VAO but no CCO). CCO or VAO were diagnosed with two or more carotid imaging studies including duplex ultrasonography, computed tomography angiography, magnetic resonance angiography, or conventional carotid angiography. Patient groups were compared with demographics, preoperative symptomatic status, and frequencies of early (2.0 mg/dL or kidney transplantation or dialysis; Coronary artery disease, percutaneous coronary intervention or coronary artery bypass graft before current admission or history of diagnosed myocardial infarction or angina; Hypertension, history of hypertension diagnosed and treated with medication, diet, and/or exercise or blood pressure greater than 140 mm Hg systolic or 90 mm Hg diastolic on at least two occasions or current use of antihypertensive pharmacological therapy; SD, standard deviation; Stroke, acute neurologic event with focal symptoms and signs, lasting for 24 hours or longer and consistent with focal cerebral ischemia; TIA, transient ischemic attack; VAO, vertebral artery occlusion. Group I, Patients without CCO and VAO; Group II, patients with CCO with or without one or both VAOs; Group III, patients with one or both VAOs but no CCO. Data are presented as number (%) unless otherwise stated. a Symptomatic, presence of neurologic or ocular symptoms within 6 months before CEA.

Table II. Comparison of demographic and clinical features among carotid artery stenting (CAS) patients Features Age, years Mean 6 SD Range Female Symptomatic Amaurosis fugax TIA Stroke Comorbidities and risk factors Hypertension Coronary artery disease Chronic kidney disease Hyperlipidemia Smoking Atrial fibrillation

Group I (n ¼ 336; 74%)

Group II (n ¼ 50; 11%)

Group III (n ¼ 69; 15%)

P

68.8 6 7.9 38-92 48 (14.3) 177 (52.7) 12 (3.6) 49 (14.6) 116 (34.5)

67.0 6 9.6 44-88 4 (8.0) 24 (48) 0 (0) 13 (26.0) 11 (22.0)

69.5 6 8.7 46-88 13 (18.8) 33 (47.8) 2 (2.9) 12 (17.4) 19 (27.5)

.241

266 90 6 225 180 16

(79.2) (26.8) (1.8) (67.0) (53.6) (4.8)

36 19 0 36 31 2

(72.0) (38.0) (0) (72.0) (62.0) (4)

58 26 3 38 35 6

(84.1) (37.7) (4.3) (55.1) (50.7) (8.7)

.249 .678 .532 .118 .142 .284 .078 .225 .101 .435 .383

CCO, Contralateral carotid occlusion; SD, standard deviation; TIA, transient ischemic attack; VAO, vertebral artery occlusion. Group I, Patients without CCO or VAO; Group II, patients with CCO with or without one or both VAOs; Group III, patients with one or both VAOs but no CCO. Data are presented as number (%) unless otherwise stated.

Table II compares the demographic and clinical features of CAS patients in the three groups and shows no significant difference in age, gender, or symptomatic status. However, diabetes mellitus was more frequent in Group III (Group I, 41.4%; Group II, 48%; Group III, 58%; P ¼ .036). ESNC developed in 18 (2.6%) patients after CEA and 37 (8.1%) patients after CAS (P < .001). When we compared postprocedural stroke alone, we found significantly higher stroke rate in CAS (1.3% for CEA vs 6.8% for CAS; P < .001); particularly, ipsilateral stroke was significantly more frequent in CAS than in CEA (1.1%

for CEA vs 6.2% for CAS; P < .001). When frequencies of ESNCs after CEA or CAS were compared according to the preoperative symptomatic status (Table III), ESNCs were significantly more frequent in CAS compared with CEA either in symptomatic or asymptomatic patients. This finding was more remarkable in patients with presenting symptoms of stroke. Interestingly, three hemorrhagic strokes developed only in symptomatic patients after CAS, not in CEA or asymptomatic CAS groups. Fig 1 shows the comparison of frequencies of ESNCs according to the treatment type and presence of the

JOURNAL OF VASCULAR SURGERY March 2014

752 Yang et al

Table III. Frequencies of early symptomatic neurologic complications (ESNCs) after carotid endarterectomy (CEA) or carotid artery stenting (CAS) according to the preoperative symptomatic status Symptomatic patients (n ¼ 487; 42%) ESNC TIA Stroke Ipsilateral infarction Nonipsilateral infarction Hemorrhagic Subtotal

CEA (n ¼ 253), No. (%) 2 (0.8) 6 (2.4) 6 (2.4) 0 0 8 (3.2)

CAS (n ¼ 234), No. (%) 5 16 12 1 3a 21

(2.1) (6.8) (5.1) (0.4) (1.3) (9)

Asymptomatic patients (n ¼ 666; 58%) P

CEA (n ¼ 445), No. (%)

.269 .018 .107 .480 .110 .007

7 3 2 1

(1.6) (0.7) (0.4) (0.2) 0 10 (2.2)

CAS (n ¼ 221), No. (%) 1 15 13 2

(0.5) (6.8) (5.9) (0.9) 0 16 (7.2)

P .281