H. J. M. Barnett

Accuracy and Prognostic Consequences of Ultrasonography in Identifying Severe Carotid Artery Stenosis

BACKGROUND AND PURPOSE The accuracy of routine ultrasonography in detecting severe carotid artery stenosis was evaluated in comparison with cerebral angiography. The precision of ultrasonographic criteria in predicting the risk of stroke was also assessed. METHODS A total of 1011 symptomatic carotid bifurcations were studied in patients from the North American Symptomatic Carotid Endarterectomy Trial (NASCET). Given that all patients were considered for entry into the trial, the chance of a verification bias affecting the analyses was minimized. The ultrasonographic data consisted of peak systolic velocities and frequency changes from both the internal and common carotid arteries. Angiographic stenosis was calculated as in NASCET. Receiver operating characteristic (ROC) curves were constructed from the ultrasonographic data for the detection of 70% or greater stenosis on the basis of an angiographic assessment. Kaplan-Meier stroke-free survival curves were used to predict the risk of stroke. RESULTS The areas under the ROC curves ranged from 0.74 to 0.75 (95% confidence interval [CI], 0.69 to 0.79). The sensitivities and specificities ranged from 0.65 to 0.71. The risk of stroke at 18 months declined sharply as the degree of angiographically defined stenosis declined from 99% to 70%. No pattern of decline was apparent on the basis of the ultrasonographic data. CONCLUSIONS The results indicate that the accuracy of ultrasonography is moderate when flow parameters are used to assess the degree of stenosis. Ultrasonography should be used as a screening tool to exclude patients with no carotid artery disease from further testing. Conventional angiography remains an essential investigation before assigning the risk of stroke and deciding appropriate treatment for extracranial carotid artery disease.

Sex difference in the effect of time from symptoms to surgery on benefit from carotid endarterectomy for transient ischemic attack and nondisabling stroke

Background and Purpose— Early studies showed that carotid endarterectomy (CEA) carried a high risk if performed within days after a large ischemic stroke. Therefore, many surgeons delay CEA for 4 to 6 weeks after any stroke. To determine the effect of delay to CEA on operative risk and benefit, we pooled data from the North American Symptomatic Carotid Endarterectomy Trial and the European Carotid Surgery Trial. Methods— Risk of ipsilateral ischemic stroke in the medical group, operative risk of stroke and death, and overall benefit from surgery were determined in relation to the time from the last symptomatic event to randomization. Operative risk of stroke and death was also determined in relation to the time to surgery. Analyses were stratified by sex and type of presenting event. Results— The 30-day perioperative risk of stroke and death was unrelated to the time since the last symptomatic event and was not increased in patients operated <2 weeks after nondisabling stroke. In contrast, the risk of ipsilateral ischemic stroke in the medical group fell rapidly with time since event (P<0.001), as did the absolute benefit from surgery (P=0.001). This decline in benefit with time was unrelated to the type of presenting event but was more pronounced in women than men (difference P<0.001). Benefit in women was confined to those randomized <2 weeks after their last event, irrespective of severity of stenosis. Conclusions— CEA can be performed safely within 2 weeks of nondisabling ischemic stroke. Benefit from endarterectomy declines rapidly with increasing delay, particularly in women.

Risk factors and outcome of patients with carotid artery stenosis presenting with lacunar stroke

Objective: To examine the relationship between carotid artery stenosis, other risk factors, and lacunar stroke. Background: Carotid artery stenosis in patients presenting with lacune stroke may be coincidental or causal. The distinction by risk factor profile is uncertain. The risk and cause of subsequent stroke, and benefit of carotid endarterectomy (CE) is unknown. Methods: Stroke in patients entering the North American Symptomatic Carotid Endarterectomy Trial were classified as nonlacunar, possible lacune (symptoms without CT lacunae), or probable lacune (symptoms with CT lacunae). Results: Of 1,158 patients with hemispheric stroke, 493 had features of lacunar stroke (283 possible and 210 probable). Lacunar stroke presented more commonly in patients with milder (<50%) degrees of internal carotid artery (ICA) stenosis (p = 0.003). History of diabetes and hyperlipidemia, not hypertension, were associated independently even after accounting for the degree of stenosis. Medically treated patients presenting with nonlacunar stroke had a low risk of subsequent lacunar events of 2.9% at 3 years in comparison with 9.2% for probable lacunar presentation (p = 0.03). For patients with 50 to 99% ICA stenosis, the relative risk reductions (RRRs) in stroke from CE were 35% when the presenting stroke was probable lacunar versus 61% when the stroke was nonlacunar. Patients presenting with a possible lacunar stroke had a 53% RRR. Conclusions: History of diabetes and hyperlipidemia were more important than arterial hypertension as risk factors for patients with lacunar stroke. Patients presenting with lacunar stroke more often had milder ICA stenosis. Although CE reduced the risk of stroke in all patients with 50 to 99% ICA stenosis, lesser benefits were observed in patients presenting with lacunar stroke.

Small, unruptured intracranial aneurysms and management of symptomatic carotid artery stenosis

Article abstract Of the 2885 patients participating in the North American Symptomatic Carotid Endarterectomy Trial, 90 (3.1%) had unruptured intracranial aneurysms (UIA), of which 96% had a diameter of less than 10 mm. During an average 5-year follow-up, only one patient had subarachnoid hemorrhage 6 days after carotid endarterectomy (CE). For patients with unrepaired UIA, the 5-year stroke risk was 10% after CE and 22.7% with best medical care. Both risks are similar to those of patients without UIA. The decision regarding CE probably should not be influenced by the presence of a small UIA.

Stroke in Renaissance Time: The Case of Francesco I de’ Medici

Francesco I de’ Medici (1541–1587), the second Grand Duke of Tuscany, was one of the members of the Medici family who ruled Florence during the centuries of the Renaissance. When, in 1857, all members of the Medici family were exhumed and definitively buried in the place where they still lie buried today, a painter, Giuseppe Moricci (Florence 1806–1879), who attended the ceremony, depicted the corpse of Francesco I in a perfect state of preservation. The painting shows a right spastic hemiparesis with a facial droop, a claw-hand appearance, the right shoulder internally rotated, the calf muscle wasted and the clubfoot confirmed by an orthopedic footwear in the coffin. The hemiparesis and consequent disability were likely concealed when Francesco I was alive, since in official portraits the Grand Duke appeared in perfect physical condition. However, chronicles reported that he had suffered from malaria and syphilis. Later in his life, temper and behavioral changes as well as emotional instability were documented, together with handwriting deterioration and seizures. We postulate that Francesco I had suffered from a stroke consequent to syphilis, a new aggressive and rapidly spreading infectious disease at that time in Italy. Francesco’s governmental skills were presumably altered due to these diseases. Disability consequent to stroke was likely concealed by official portrayers and biographers of Francesco I during his life, consistent with the King’s two bodies theory common since the Middle Ages: while the King’s physical body is destined to die, the political one is everlasting. Infectious diseases have remained a leading cause of stroke in underdeveloped countries until recently, but noncommunicable causes are now prevailing worldwide.