Jürgen Eggers

Effect of ultrasound on thrombolysis of middle cerebral artery occlusion.

We studied the effect of transcranial 2MHz Doppler ultrasound (US) on the recanalization and outcome of stroke patients suffering from acute middle cerebral artery occlusion. All patients underwent intravenous recombinant tissue‐type plasminogen activator thrombolysis. Eleven patients were randomly selected for continuous US monitoring (C‐US) over 1 hour; 14 patients were selected for the control group. The C‐US group showed a higher grade of recanalization after 1 hour but also a higher number of intraparenchymal bleedings. Overall, a favorable functional outcome occurred more frequently in the C‐US group (Barthel index, p = 0.037) after 3 months. Ann Neurol 2003;53:797–800

Sonothrombolysis in acute ischemic stroke for patients ineligible for rt-PA

The authors studied the effect of transcranial ultrasound on patients with acute middle cerebral artery occlusion and contraindications for thrombolysis. Fifteen consecutive subjects were randomized for insonation over 1 hour or for inclusion in a control group. By day 4, recanalization and neurologic improvement occurred more frequently in the target group. Ultrasound-induced acceleration of clot dissolution may be an option for patients with contraindications for recombinant tissue plasminogen activator.

MRI findings and stroke risk in TIA patients with different symptom durations

Objective: To determine the frequency of acute infarction detected by diffusion-weighted imaging (DWI)-MRI and stroke risk in TIA patients with different symptom duration in a population-based study. Methods: During a 54-month period (starting November 2007), 3,724 admitted patients (mean age, 67 ± 14 years; 45% women) with transient neurologic symptoms lasting <24 hours from 15 hospitals were included. All patients underwent DWI-MRI during hospitalization. Results: Of 3,724 patients, 1,166 showed an acute infarction (32.2%; 95% confidence interval [CI], 30.8%–33.8%) and 88 (2.4%; 95% CI, 1.9%–2.9%) had a stroke during hospitalization (7 days). Stroke risk was higher in patients with tissue-positive DWI than in those with tissue-negative DWI (4.5% vs 1.5%, respectively; p < 0.001). Logistic regression analysis revealed that stroke risk was correlated with positive DWI (odds ratio [OR], 3.1; 95% CI, 2.0–4.8; p < 0.001), atrial fibrillation (OR, 2.1; 95% CI, 1.3–3.5; p = 0.001), and symptom duration <1 hour (OR, 1.5; 95% CI, 1.0–2.4; p = 0.042). Patients with symptoms lasting <1 hour had a lower rate of acute infarction than those with symptoms lasting ≥1 hour (24% vs 36%, respectively; p < 0.001), whereas stroke risk did not differ between the groups (2.8% vs 2.1%, respectively; p = 0.22). Stroke risk was higher after tissue-positive events than tissue-negative ones in patients with symptom duration <1 hour (5.2% vs 2.0%, respectively; p = 0.002) and in those with symptom duration ≥1 hour (4.1% vs 1.1%, respectively; p < 0.001). Conclusion: Stroke risk was higher after tissue-positive events than tissue-negative ones in TIA patients with different symptom duration.

Statin treatment in patients with acute ischemic stroke.

Background and purpose We aimed to investigate the association of statin treatment with outcomes in patients with acute ischemic stroke. Methods Over a 4.5-year period (starting November 2007), 12 781 patients (mean age, 72·8 ± 12·6 years; 48·6% women) with acute ischemic stroke from 15 hospitals in Schleswig-Holstein, Germany, were enrolled in a population-based study and prospectively evaluated. The primary outcomes were the mortality during hospitalization and the disability (modified Rankin Scale score ≥2) at discharge from hospital. The secondary outcomes were the mortality and disability at three-months after discharge. Results A total of 7535 patients (59%) with acute ischemic stroke were treated with statins. During hospitalization (mean, nine-days), the in-hospital mortality rate (4·7%; 95% confidence interval, 4·3–5·1%) was lower in patients treated with statins than in those without statins (2·3% vs. 7·9%, respectively; P < 0·001). At three-months after discharge, the mortality rate (6·9%; 95% confidence interval, 6·4–7·5%) was lower in patients treated with statins than in those without statins (5·0% vs. 10·6%, respectively; P < 0·001). Adjusted logistic regression analysis showed that statin treatment was associated with reduced rates of in-hospital mortality (odds ratio, 0·39; 95% confidence interval, 0·31–0·48; P < 0·001) and three-month mortality (odds ratio, 0.47; 95% confidence interval, 0·34–0·63; P < 0·001). A comparison of the patient groups revealed that patients on statins were likely to have lower disability rates at discharge (59% vs. 67%, respectively; P < 0·001) and after three-months (33% vs. 42%, respectively; P < 0·001) in patients who had survived the stroke. Conclusion Statin treatment may improve the outcomes in patients with acute ischemic stroke. Further studies are necessary to confirm this finding.

Short-term risk and predictors of stroke after transient ischemic attack

BACKGROUND Transient ischemic attack (TIA) is a marker of stroke, especially in the early phase following this event. The aims of this study are to determine the short-term risk of stroke and to evaluate the independent predictors of stroke in patients with TIA who are hospitalized within 48 hours after symptom onset. METHODS During a 36-month period (beginning in November 2007), 3554 patients (mean age: 70.5 ± 13 years; 49.9% female; mean NIHSS score: 1.4 ± 2.5) from 15 hospitals suffering from TIA were prospectively evaluated. RESULTS Of the 3554 patients, 43 (1.2%) suffered from stroke during hospitalization (6.5 ± 4.3 days). We identified the following independent predictors for stroke after TIA: male sex (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.3-5; P=0.008), age ≥65 years (OR, 4.7; 95% CI, 1.4-15; P=0.01), hyperlipidemia (OR, 2.4; 95% CI, 1.2-4.8; P=0.015), and dysarthria (OR, 2; 95% CI, 1.1-5.0; P=0.038). CONCLUSION Patient characteristics (male sex, age, and hyperlipidemia) and TIA symptom (dysarthria) may be useful in defining stroke after TIA in patients who were hospitalized with TIA.

Use of cranial CT to identify a new infarct in patients with a transient ischemic attack

Research on infarct detection by noncontrast cranial computed tomography (CCT) in patients with transient ischemic attack (TIA) is sparse. However, the aims of this study are to determine the frequency of new infarcts in patients with TIA, to evaluate the independent predictors of infarct detection, and to investigate the association between a new infarct and early short‐term risk of stroke during hospitalization. We prospectively evaluated 1533 consecutive patients (mean age, 75.3 ± 11 years; 54% female; mean National Institutes of Health Stroke Scale [NIHSS] score, 1.7 ± 2.9) with TIA who were admitted to hospital within 48 h of symptom onset. A new infarct was detected by CCT in 47 (3.1%) of the 1533 patients. During hospitalization, 17 patients suffered a stroke. Multivariate logistic regression analysis revealed the following independent predictors for infarct detection: NIHSS score ≥10 (odds ratio [OR], 4.8), time to CCT assessment >6 h (OR 2.2), and diabetes (OR 2.3). The evidence of a new infarct was not associated with the risk of stroke after TIA. The frequency of a new infarct in patients with TIA using CCT is low. The use of the CCT tool to predict the stroke risk during hospitalization in patients with TIA is found to be inappropriate. The estimated clinical predictors are easy to use and may help clinicians in the TIA work up.

Stroke recurrence in patients with recently symptomatic carotid stenosis and scheduled for carotid revascularization

Patients with symptomatic carotid stenosis (sCS) have a higher risk of stroke recurrence following the first ischaemic event. Guidelines recommend that patients undergo carotid revascularization (CR), preferably within 2 weeks of the event. We aimed to determine the rate of stroke recurrence during hospitalization in patients who were admitted to the hospital with an acute ischaemic event and who underwent CR for recently sCS.

Introduction of a new model for time-continuous and non-contact investigations of in-vitro thrombolysis under physiological flow conditions

BackgroundThrombolysis is a dynamic and time-dependent process influenced by the haemodynamic conditions. Currently there is no model that allows for time-continuous, non-contact measurements under physiological flow conditions. The aim of this work was to introduce such a model.MethodsThe model is based on a computer-controlled pump providing variable constant or pulsatile flows in a tube system filled with blood substitute. Clots can be fixed in a custom-built clot carrier within the tube system. The pressure decline at the clot carrier is measured as a novel way to measure lysis of the clot. With different experiments the hydrodynamic properties and reliability of the model were analyzed. Finally, the lysis rate of clots generated from human platelet rich plasma (PRP) was measured during a one hour combined application of diagnostic ultrasound (2 MHz, 0.179 W/cm2) and a thrombolytic agent (rt-PA) as it is commonly used for clinical sonothrombolysis treatments.ResultsAll hydrodynamic parameters can be adjusted and measured with high accuracy. First experiments with sonothrombolysis demonstrated the feasibility of the model despite low lysis rates.ConclusionsThe model allows to adjust accurately all hydrodynamic parameters affecting thrombolysis under physiological flow conditions and for non-contact, time-continuous measurements. Low lysis rates of first sonothrombolysis experiments are primarily attributable to the high stability of the used PRP-clots.

In Vitro Examination of the Thrombolytic Efficacy of Desmoteplase and Therapeutic Ultrasound Compared with rt-PA

The aim of the study described here was to evaluate the thrombolytic efficacy of combined treatment with the fibrin-selective plasminogen activator desmoteplase (DSPA) and therapeutic ultrasound (sonothrombolysis [STL]) compared with conventional rt-PA (recombinant tissue plasminogen activator) treatment in vitro. Lysis rates were determined by the weight loss of platelet-rich plasma (PRP) clots treated with rt-PA (60 kU/mL) or DSPA (2 μg/mL) combined with pulsed wave ultrasound (2 MHz, 0.179 W/cm(2)). To reveal the individual effects of medication and ultrasound, lysis rates were also determined for DSPA monotherapy and for combined treatment with rt-PA and ultrasound. Clots solely placed in plasma served as the control group. Lysis increased significantly with rt-PA (26.5 ± 7.8%) and DSPA (30.5 ± 6%) compared with the control group (18.2 ± 5.9%) (each p < 0.001). DSPA lysis was more effective than rt-PA lysis (without STL: p = 0.015, with STL: p = 0.01). Combined treatment with DSPA and 2-MHz STL significantly exceeded rt-PA lysis (32.8% vs. 26.5%, p < 0.001).

Acute brain infarction detected by CCT and stroke risk in patients with transient ischemic attack lasting <1 hour

Background and purpose: This study aimed to determine the frequency and associated factors of acute brain infarction (ABI) detected by noncontrast cranial computed tomography (CCT) in patients with transient ischemic attack (TIA) of symptom duration <1 h and to investigate the association between evidence of ABI and short-term risk of stroke. Methods: During a 54-month period (starting November 2007), consecutive patients with TIA (symptom duration <1 h) admitted and imaged with CCT were prospectively evaluated. Adjusted logistic regression was used to estimate odds ratios (ORs). Results: Of 1021 patients (mean age, 74.5 ± 11 years; 52% female) with TIA (symptom duration <1 h) imaged with CCT at admission, 68 patients (6.7%; 95% CI, 5.3–8.3%) exhibited TIA-related ABI. Adjusted logistic regression showed that ABI was independently correlated with atrial fibrillation (AF) (OR, 3.3; 95% CI, 1.4–7.9; p = 0.006) and time between onset and CT assessment >6 h (OR, 2.5; 95% CI, 1.1–6.1; p = 0.034). During hospitalization (5 ± 3 d), 22 patients (2.2%; 95% CI, 1.4–3.1%) developed a stroke. Patients with ABI had higher stroke rates than those without (10.3% and 1.6%, respectively; p < 0.001). Adjusted logistic regression revealed that stroke risk was independently correlated with ABI (OR, 5.3; 95% CI, 1.8–15.0; p = 0.002) and AF (OR, 2.6; 95% CI, 1.1–6.4; p = 0.026). Conclusions: Detection of ABI by CCT in TIA patients with symptom duration <1 h may depend on timing of CCT assessment and presence of AF. Evidence of ABI indicates an elevated stroke risk during hospitalization.