Amaurosis Fugax: Is it Innocuous? David Rosenthal, MD, John C. Hungerpiller, MD, Mark E. Crispin, MD, Michael D. Clark, MD, Pano A. Lamis, MD, L. Laszlo Pallos, PhD*, Atlanta, Georgia
A 10 year retrospective study of 103 patients with amaurosis fugax was done. Sixty-two patients with symptoms of amaurosis fugax underwent arteriography, which demonstrated ulcerated carotid plaque in 36 and hemodynamically significant stenoses (>75% diameter reduction) in 26. These 62 patients underwent carotid endarterectomy. The other 41 patients who had proven ulcerated plaque (33 patients) or hemodynamic stenoses (eight patients) were not treated surgically and served as a control series. No strokes or deaths occurred in the immediate postoperative period. Follow-up of the 62 operated patients extending to 10 years (mean 4.2 years), revealed one (1.6%) patient with recurrent amaurosis fugax symptoms, two (3.2%) with transient ischemic attacks, and one (1.6%) with a stroke in the operated hemisphere. In the nonoperated group, despite aspirin or warfarin treatment, four (9.7%) patients had ongoing amaurosis fugax symptoms, and two (4.8%) developed transient ischemic attacks that led to carotid endarterectomy. One (2.4%) other patient developed sudden, permanent monocular blindness, and two (4.8%) suffered hemispheric strokes, one of which was fatal. The cumulative morbidity (ongoing ocular or transient ischemic attack symptoms, perioperative and late stroke) in the operated group was 6.4% (four patients), while the cumulative morbidity in the nonoperated group was significantly higher at 21.9% (nine patients) (p = 0.02). When patients present with symptoms of amaurosis fugax and have demonstrable carotid bifurcation disease, carotid endarterectomy is recommended. Amaurosis fugax should be regarded as a harbinger of monocular blindness and stroke. (Ann Vasc Surg 1992; 6:281-288). KEY WORDS: Amaurosis fugax; carotid endarterectomy; stroke; carotid artery lesions; blindness.
In 1951, C. Miller Fisher [1] first reported the association of sudden, transient, monocular visual loss and hemiplegia with internal carotid artery occlusion. In this initial report of "fleeting blindness" or amaurosis fugax, Fisher attributed these clinical symptoms to occlusion or stenosis of the internal carotid artery on the side of the affected From the Department of Vascular Surgery, Georgia Baptist Medical Center, Medical College of Georgia, and the Agency for Toxic Substances*, Atlanta, Georgia. Reprint requests: David Rosenthal, MD, 315 Boulevard N.E., Suite 412, Atlanta, Georgia 30312.
eye. Three years after Fisher's report, Felix Eastcott, George Pickering and Charles Rob reported the first successful carotid artery reconstruction in a housewife who experienced 33 episodes of transient right arm and leg paralysis associated with left eye amaurosis fugax. During the nearly four decades since these landmark reports, innumerable publications have attempted to define the most appropriate course of management for patients with extracranial carotid artery disease who experience amaurosis fugax. Still, the question remains: is amaurosis fugax simply a minor problem to be treated with antiplatelet
281
AMA UROSIS F U G A X
282
ANNALS OF VASCULAR SURGERY
TABLE I.--Carotid bifurcation disease identified by arteriography or duplex ultrasonography
100 80
Percent diameter reduction
~60
14J O n"
CEA (n = 62) Percent No.
75%
w40 Ix.
20 CEA
CAHD
HT
DM
9.7% 16.2% 32.2% 41.9%
6 10 20 26
Nonoperated (n = 41) Percent No. 9.8% 26.8% 43.9% 19.5%
4 11 18 8
= carotid endarterectomy
SMOKING
Fig. 1. Patient profile risk factors for operated and nonoperated patients. CAHD = coronary artery heart disease; DM = diabetes mellitus; HT = hypertension.
or anticoagulant medications, or should it be regarded as a warning signal of possible monocular blindness or stroke? To evaluate this problem, a 10 year retrospective study of 103 patients with amaurosis fugax was carried out.
MATERIALS AND METHODS One hundred and three patients with amaurosis fugax as the presenting symptom were evaluated at Georgia Baptist Medical Center, Atlanta, Georgia between January 1979 and December 1989. Ninetyone (88%) of the patients underwent neuroopthalmologic assessment to rule out other vascular and nonvascular causes of transient visual loss. For purposes of this study, amaurosis fugax was defined as sudden, partial, or complete monocular visual loss lasting less than 24 hours. Sixty-two patients with amaurosis fugax and arteriographically established carotid bifurcation disease underwent carotid endarterectomy (CEA). Forty-one other patients with symptoms of amaurosis fugax and carotid artery disease established by arteriography (35 patients) or duplex ultrasonography (six patients) were not operated; these patients served as a control series. Patients were placed into the operated or nonoperated groups based on referring physician preference. In general, patients with hemodynamically significant (>75% stenosis) carotid bifurcation disease were referred for operation. Because the operated and control groups were nonramdomized, all statistical conclusions must be guarded. Risk factors in the operated and nonoperated patients were similar (Fig. I). Fifty-nine of the 103 patients were men. The mean age was 64.4 years (range 42-81 years). A history consistent with coronary artery disease was present in 54 patients, and hypertension was present in 56 patients. Forty
patients had diabetes mellitus, and 87 patients had a history of cigarette smoking. Ninety-seven of the patients underwent fourvessel arch arteriography with visualization of the extra- and intracranial circulation. Six nonoperated patients underwent duplex ultrasonography of the extracranial carotid arteries. Forty-six CEAs were performed with a temporary indwelling shunt, 16 with continuous 12-lead electroencephalographic monitoring, and three without a shunt. All CEAs were performed with the patients under general anesthesia. All operated patients were clinically evaluated in the immediate postoperative period (30 days). Long-term follow-up of these patients ranged from two to 120 months (mean -+ SD, 46 -+ 4.0 months; median, 42 months). The long-term follow-up for the nonoperated patients ranged from four to 96 months (mean -+ SD, 40.1 -+ 3.6 months; median, 39 months). If follow-up evaluation showed no further ocular or hemispheric symptoms, the patient was classified as improved or asymptomatic. To gather survival data and to determine the quality of life after CEA, the patients were evaluated during office visit, contacted by letter, or interviewed by telephone. Seventeen patients were lost to follow-up, l! from the operated group and six from the nonoperated group. Statistical analysis was performed by chi-square analysis, Student's T-test and life table method, where appropriate.
RESULTS Sixty-two patients with symptoms of amaurosis fugax underwent four vessel arch arteriography, prior to CEA. Arteriography demonstrated ulcerated carotid bifurcation plaque in 60% (36/62) and hemodynamically significant stenoses (>75% diameter reduction) in 40% (26/62) (Table I). Forty-one other patients with symptoms of amaurosis fugax also had four vessel arch arteriography (35 patients) or duplex ultrasonography (six patients), which demonstrated ulcerated carotid plaque in 80% (33/ 41) and hemodynamically significant stenoses in 20% (8/41) (Table I). These patients were not oper-
VOLUME 6 N o 3 - 1992
AMAUROSIS FUGAX
283
TABLE tl.--Recurrent ipsilateral amaurosis fugax after CEA Interval (months)
At risk
0-12 12-24 24-36 36-48 48-60 60-72 72-84 84-96 96-108 108-120
61 48 45 34 26 16 12 9 3 2
Withdrawn
No. of AF in interval
Interval AF rate (%)
Cumulative AF free rate (%)
12 3 11 8 10 4 3 6 1 2
1 0 0 0 0 0 0 0 0 0
1.6 0 0 0 0 0 0 0 0 0
98.4 98.4 98.4 98.4 98.4 98.4 98.4 98.4 98.4 98.4
C E A = carotid e n d a ~ e r e c t o m y ; A F = a m a u r o s i s f u g a x
ated but were treated with aspirin/dipyridamole (31 patients) or warfarin (10 patients). There were no strokes or deaths after CEA in the immediate 30-day postoperative period. After CEA all patients were placed on aspirin (325 mg daily) and dipyridamole (150 mg daily). In follow-up extending to I0 years (mean 46.1 months), one (1.6%) patient developed recurrent amaurosis fugax symptoms 11 months after CEA (Table II, Fig. 2), two (3.2%) had transient ischemic attacks (TIA) 51 and 73 months after CEA (Table III, Fig. 3), and one (1.6%) sustained a stroke in the operated hemisphere 33 months after operation (Table IV, Fig. 4). 100.~
uJ I11
..... 0
0
0
0
..... 0
0
0
0
0
E8o x ¢0 IZ ill
=Operated
w I1..
Nonoperated
t2 MONTHS
Fig. 2. Cumulative incidence of recurrent amaurosis fugax.
These patients underwent repeat arteriography and computed tomography (CT) brain scan. No arterial or ocular pathology could be identified in the patient who experienced the recurrent amaurosis fugax symptoms. When he was treated empirically with aspirin (325 mg daily) and "low dose" warfarin to maintain prothrombin time at approximately 16 seconds, his symptoms abated. One patient with TIAs had a high-grade recurrent carotid stenosis documented by arteriography 51 months after CEA. This necessitated reoperation and saphenous vein carotid patch angioplasty. The other patient who experienced TIAs had no carotid bifurcation pathology identified by arteriography 73 months after CEA and was treated with aspirin and dipyridamole. The final patient, who suffered a late stroke in the operated hemisphere 33 months after CEA, had a middle cerebral artery thrombosis identified at arteriography and a thrombotic infarct on CT brain scan. A hemodynamically insignificant (40% diameter reduction) smooth recurrent stenosis was identified at the original CEA site. In follow-up extending to eight years (mean 40.1 months), ipsilateral carotid-related morbidity was noted in nine of the nonoperated patients. Four (9.7%) patients had ongoing amaurosis fugax symptoms within 12 months of diagnosis; at initial arteriography one patient had
A 10 year retrospective study of 103 patients with amaurosis fugax was done. Sixty-two patients with symptoms of amaurosis fugax underwent arteriography, which demonstrated ulcerated carotid plaque in 36 and hemodynamically significant stenoses (>75% diameter reduction) in 26. These 62 patients underwent carotid endarterectomy. The other 41 patients who had proven ulcerated plaque (33 patients) or hemodynamic stenoses (eight patients) were not treated surgically and served as a control series. No strokes or deaths occurred in the immediate postoperative period. Follow-up of the 62 operated patients extending to 10 years (mean 4.2 years), revealed one (1.6%) patient with recurrent amaurosis fugax symptoms, two (3.2%) with transient ischemic attacks, and one (1.6%) with a stroke in the operated hemisphere. In the nonoperated group, despite aspirin or warfarin treatment, four (9.7%) patients had ongoing amaurosis fugax symptoms, and two (4.8%) developed transient ischemic attacks that led to carotid endarterectomy. One (2.4%) other patient developed sudden, permanent monocular blindness, and two (4.8%) suffered hemispheric strokes, one of which was fatal. The cumulative morbidity (ongoing ocular or transient ischemic attack symptoms, perioperative and late stroke) in the operated group was 6.4% (four patients), while the cumulative morbidity in the nonoperated group was significantly higher at 21.9% (nine patients) (p = 0.02). When patients present with symptoms of amaurosis fugax and have demonstrable carotid bifurcation disease, carotid endarterectomy is recommended. Amaurosis fugax should be regarded as a harbinger of monocular blindness and stroke. (Ann Vasc Surg 1992; 6:281-288). KEY WORDS: Amaurosis fugax; carotid endarterectomy; stroke; carotid artery lesions; blindness.
In 1951, C. Miller Fisher [1] first reported the association of sudden, transient, monocular visual loss and hemiplegia with internal carotid artery occlusion. In this initial report of "fleeting blindness" or amaurosis fugax, Fisher attributed these clinical symptoms to occlusion or stenosis of the internal carotid artery on the side of the affected From the Department of Vascular Surgery, Georgia Baptist Medical Center, Medical College of Georgia, and the Agency for Toxic Substances*, Atlanta, Georgia. Reprint requests: David Rosenthal, MD, 315 Boulevard N.E., Suite 412, Atlanta, Georgia 30312.
eye. Three years after Fisher's report, Felix Eastcott, George Pickering and Charles Rob reported the first successful carotid artery reconstruction in a housewife who experienced 33 episodes of transient right arm and leg paralysis associated with left eye amaurosis fugax. During the nearly four decades since these landmark reports, innumerable publications have attempted to define the most appropriate course of management for patients with extracranial carotid artery disease who experience amaurosis fugax. Still, the question remains: is amaurosis fugax simply a minor problem to be treated with antiplatelet
281
AMA UROSIS F U G A X
282
ANNALS OF VASCULAR SURGERY
TABLE I.--Carotid bifurcation disease identified by arteriography or duplex ultrasonography
100 80
Percent diameter reduction
~60
14J O n"
CEA (n = 62) Percent No.
75%
w40 Ix.
20 CEA
CAHD
HT
DM
9.7% 16.2% 32.2% 41.9%
6 10 20 26
Nonoperated (n = 41) Percent No. 9.8% 26.8% 43.9% 19.5%
4 11 18 8
= carotid endarterectomy
SMOKING
Fig. 1. Patient profile risk factors for operated and nonoperated patients. CAHD = coronary artery heart disease; DM = diabetes mellitus; HT = hypertension.
or anticoagulant medications, or should it be regarded as a warning signal of possible monocular blindness or stroke? To evaluate this problem, a 10 year retrospective study of 103 patients with amaurosis fugax was carried out.
MATERIALS AND METHODS One hundred and three patients with amaurosis fugax as the presenting symptom were evaluated at Georgia Baptist Medical Center, Atlanta, Georgia between January 1979 and December 1989. Ninetyone (88%) of the patients underwent neuroopthalmologic assessment to rule out other vascular and nonvascular causes of transient visual loss. For purposes of this study, amaurosis fugax was defined as sudden, partial, or complete monocular visual loss lasting less than 24 hours. Sixty-two patients with amaurosis fugax and arteriographically established carotid bifurcation disease underwent carotid endarterectomy (CEA). Forty-one other patients with symptoms of amaurosis fugax and carotid artery disease established by arteriography (35 patients) or duplex ultrasonography (six patients) were not operated; these patients served as a control series. Patients were placed into the operated or nonoperated groups based on referring physician preference. In general, patients with hemodynamically significant (>75% stenosis) carotid bifurcation disease were referred for operation. Because the operated and control groups were nonramdomized, all statistical conclusions must be guarded. Risk factors in the operated and nonoperated patients were similar (Fig. I). Fifty-nine of the 103 patients were men. The mean age was 64.4 years (range 42-81 years). A history consistent with coronary artery disease was present in 54 patients, and hypertension was present in 56 patients. Forty
patients had diabetes mellitus, and 87 patients had a history of cigarette smoking. Ninety-seven of the patients underwent fourvessel arch arteriography with visualization of the extra- and intracranial circulation. Six nonoperated patients underwent duplex ultrasonography of the extracranial carotid arteries. Forty-six CEAs were performed with a temporary indwelling shunt, 16 with continuous 12-lead electroencephalographic monitoring, and three without a shunt. All CEAs were performed with the patients under general anesthesia. All operated patients were clinically evaluated in the immediate postoperative period (30 days). Long-term follow-up of these patients ranged from two to 120 months (mean -+ SD, 46 -+ 4.0 months; median, 42 months). The long-term follow-up for the nonoperated patients ranged from four to 96 months (mean -+ SD, 40.1 -+ 3.6 months; median, 39 months). If follow-up evaluation showed no further ocular or hemispheric symptoms, the patient was classified as improved or asymptomatic. To gather survival data and to determine the quality of life after CEA, the patients were evaluated during office visit, contacted by letter, or interviewed by telephone. Seventeen patients were lost to follow-up, l! from the operated group and six from the nonoperated group. Statistical analysis was performed by chi-square analysis, Student's T-test and life table method, where appropriate.
RESULTS Sixty-two patients with symptoms of amaurosis fugax underwent four vessel arch arteriography, prior to CEA. Arteriography demonstrated ulcerated carotid bifurcation plaque in 60% (36/62) and hemodynamically significant stenoses (>75% diameter reduction) in 40% (26/62) (Table I). Forty-one other patients with symptoms of amaurosis fugax also had four vessel arch arteriography (35 patients) or duplex ultrasonography (six patients), which demonstrated ulcerated carotid plaque in 80% (33/ 41) and hemodynamically significant stenoses in 20% (8/41) (Table I). These patients were not oper-
VOLUME 6 N o 3 - 1992
AMAUROSIS FUGAX
283
TABLE tl.--Recurrent ipsilateral amaurosis fugax after CEA Interval (months)
At risk
0-12 12-24 24-36 36-48 48-60 60-72 72-84 84-96 96-108 108-120
61 48 45 34 26 16 12 9 3 2
Withdrawn
No. of AF in interval
Interval AF rate (%)
Cumulative AF free rate (%)
12 3 11 8 10 4 3 6 1 2
1 0 0 0 0 0 0 0 0 0
1.6 0 0 0 0 0 0 0 0 0
98.4 98.4 98.4 98.4 98.4 98.4 98.4 98.4 98.4 98.4
C E A = carotid e n d a ~ e r e c t o m y ; A F = a m a u r o s i s f u g a x
ated but were treated with aspirin/dipyridamole (31 patients) or warfarin (10 patients). There were no strokes or deaths after CEA in the immediate 30-day postoperative period. After CEA all patients were placed on aspirin (325 mg daily) and dipyridamole (150 mg daily). In follow-up extending to I0 years (mean 46.1 months), one (1.6%) patient developed recurrent amaurosis fugax symptoms 11 months after CEA (Table II, Fig. 2), two (3.2%) had transient ischemic attacks (TIA) 51 and 73 months after CEA (Table III, Fig. 3), and one (1.6%) sustained a stroke in the operated hemisphere 33 months after operation (Table IV, Fig. 4). 100.~
uJ I11
..... 0
0
0
0
..... 0
0
0
0
0
E8o x ¢0 IZ ill
=Operated
w I1..
Nonoperated
t2 MONTHS
Fig. 2. Cumulative incidence of recurrent amaurosis fugax.
These patients underwent repeat arteriography and computed tomography (CT) brain scan. No arterial or ocular pathology could be identified in the patient who experienced the recurrent amaurosis fugax symptoms. When he was treated empirically with aspirin (325 mg daily) and "low dose" warfarin to maintain prothrombin time at approximately 16 seconds, his symptoms abated. One patient with TIAs had a high-grade recurrent carotid stenosis documented by arteriography 51 months after CEA. This necessitated reoperation and saphenous vein carotid patch angioplasty. The other patient who experienced TIAs had no carotid bifurcation pathology identified by arteriography 73 months after CEA and was treated with aspirin and dipyridamole. The final patient, who suffered a late stroke in the operated hemisphere 33 months after CEA, had a middle cerebral artery thrombosis identified at arteriography and a thrombotic infarct on CT brain scan. A hemodynamically insignificant (40% diameter reduction) smooth recurrent stenosis was identified at the original CEA site. In follow-up extending to eight years (mean 40.1 months), ipsilateral carotid-related morbidity was noted in nine of the nonoperated patients. Four (9.7%) patients had ongoing amaurosis fugax symptoms within 12 months of diagnosis; at initial arteriography one patient had
