الفهرس 
Introduction and aim of the workOnly 14 pages are availabe for public view
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Abstract
Stroke is a leading cause of functional impairments; with 20%
of survivors requiring institutional care after 3 months and 15% to
30% being permanently disabled. In Egypt, the incidence of stroke
was found to be 2.1 per 1000 population, while the prevalence was
5.4 per 1000 population.
The 90-day risk of a subsequent stroke following an acute transient ischemic attack (TIA) or minor stroke is approximately as high as 20%. Identification of those patients at the highest risk for recurrent stroke may allow risk-specific management strategies to be implemented. The risk of stroke recurrence is partly dependent on the mechanism underlying the original event. Early identification of this mechanism may improve the ability to early detect recurrence and prevent deterioration.
In this study a group of 60 patients with acute cerebral ischemic event either transient ischemic attacks (TIA) or acute ischemic stroke (AIS) were recruited and followed up. The study was carried out at Matariya Teaching Hospital, Cairo, Egypt. All participants were subjected to intensive history taking, neurological examination and investigation to determine the presence of risk factors of the stroke incidence. Transcranial Doppler examination was done initially after emergency brain imaging and follow up of cerebral hemodynamics at fixed intervals (at days 2, 7, 30 and 90) to detect early changes of cerebral
hemodynamics and its relation to early recurrence.
At the end of the study, 12 patients (20%) developed early recurrence of stroke. All the recurrences were ischemic affecting same arterial territory of original event.
A risk estimation model was used to examine the association between modifiable risk factors and early stroke recurrence. Our data results showed that diabetes (n=11, 91.7%), atrial fibrillation (n=10, 83.3%) and past history of cerebral ischemia (n=8, 66.7%) achieved the highest prevalence among patients with early recurrent stroke. Analysis of the risk estimation model results showed a tendency for patient who develop early recurrence to have diabetes (RR =5.5, OR = 7.2, P <0.05), atrial fibrillation (RR =4.4, OR =5.2, P <0.05) and past history of cerebral ischemia (RR =3.5, OR =8.7, P <0.001).
Using ABCD2 score as a clinical risk stratification model; the results of current study achieved a statistically significant relationship between distributions of ABCD2 score among our study patients (P <0.001). where our patients with early recurrence tended to achieve higher ABCD2 score (81.7%) [n=8, 66.7% for high risk & n=3, 25% for moderate risk].
Transcranial Doppler ultrasound (TCD) examination was determined for all study patients as a bedside evaluation of intracranial hemodynamic state. Initially after the index event, 45 patients (75%) with disturbed intracranial hemodynamics (27 hyperemic and 18 stenotic) were reported. The statistical analysis showed a significant distribution (P <0.05), where patients with acute ischemic event tended to have abnormally increased mean flow velocity (MFV) of symptomatic intracerebral arteries.
The follow up of the patients is determined for 90 days after index event by serial TCD examination to detect any changes in intracranial hemodynamic parameters and correlated with early signs of stroke recurrence. Comparing the means of MFV of symptomatic intracranial vessels of patients who developed early recurrence with those who didn’t, we found a significant and independent association between mean flow velocities (MFV) in cerebral arteries and the risk of early stroke recurrence (P <0.05); where patients with early recurrence tended to have a higher MFV (M =75.9 ± 11.2) at the end of follow up period.
TCD can help predict early stroke and recurrent TIA risk by detecting micro-embolic signals (MES), which are most frequently seen in patients with unstable atherosclerotic carotid plaque. In this study, MES detection in patients with acute stroke showed an independent highly significant association with early ischemic recurrence (P <0.001). Moreover, MES-positive patients (22/60 patients) showed higher risk (RR= 8.636, OR= 15) of developing recurrent stroke during ensuing 90 days after ischemic event.
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Finally, this study confirms the important previous finding that the risk of stroke recurrence is highest in the immediate period after index stroke. Also, the major finding of the present work is the demonstration of the value of TCD in the evaluation of hemodynamic patterns after acute stroke and its relation to early recurrence. Consequently, initiation and monitoring of secondary preventative treatment without delay appear to be paramount.