الفهرس 
Acknowledgement
Acute ischemic StrokeOnly 14 pages are availabe for public view
 |  | from | 32 |  |  |
| | | from | 32 | | |
Abstract
Stroke considered the most common cause of death and disability in low-income and middle-income countries. According to World Health Organization (WHO) records from 2001 death from stroke in low-income and middle-income countries accounted for 85,5% of stroke deaths worldwide, and the disability adjusted life years lost in these countries was almost seven times those lost in high-income countries.
The main aim of acute stroke management is restoring blood flow in the acutely occluded cerebral artery, this can be done by various measures. In 1995 IV rtPA was introduced as a first successful treatment of acute stroke, but with clinical practice several limitations occurred in face of iv rtPA, the most common two limitations were narrow time window for thrombolytic therapy (4.5 h) and failure to achieve recanalization in large vessel occlusions. Continuous endeavor was done in order to overcome this obstacles, IA thrombolysis was used, it partially solved the problem of narrow time window by extending the time window into 6 hours instead of 4.5 h, however the problem of successful recanalization in big vessels stayed unresolved as IA thrombolysis produced unsatisfactory results, although better than IV rtPA. Mechanical thrombectomy was emerged as an good alternative to IV and IA thrombolysis, as its can be used safely in patients have any contraindications for thrombolytic therapy, can be given within longer time window (up to 8 hours) and higher recanalization rates than both previous methods. The major problem stood against managing acute stroke patients with mechanical thrombectomy was prolonged time from stroke onset till reaching specialized center offering this advanced management technique (prolonged door to needle). In order to overcome this problem, an strategy was emerged aiming to initial management of those patients with IV rtPA (when there were no contraindication for it) to save their time window till receiving mechanical thrombectomy, this strategy was called bridging therapy. However it was not known whether combination of IV rtPA and mechanical thrombectomy is more effective and safer, or mechanical thrombectomy alone could produce similar efficacy and safety. Moreover impact of time on clinical outcome of patients treated with IV thrombolytic therapy is already proven to play amajor role, however its impact on interventional management not well studied before. In order to reach the best management modality in patients with large vessel occlusion, we compared in our thesis between patients received bridging therapy (combined IV rtPA and mechanical thrombectomy) and patients received non bridging therapy (mechanical thrombectomy alone). We investigated also the impact of time on intervention process and whether it plays a major role or not. We investigated also the most common complications and prognostic factors of intervention process to select the best patients whom could maximally benefit from interventional management of stroke.
All patients above 18 year were admitted with acute ischemic stroke during the therapeutic time window in the stroke unit of Saarland university hospital and had one of the following occlusions:
•Acute internal carotid artery occlusion.
•Acute internal carotid bifurcation (Carotid T)-occlusion.
•Acute middle cerebral artery M1 or M2 occlusion.
•Acute anterior cerebral artery (A1) occlusion
•Acute vertebral artery, basilar artery and post cerebral artery (P1) occlusion.
were included in our thesis.
Patients had any contraindication for rtPA had received mechanical thrombectomy alone, while those without any contraindication received rtPA and mechanical thrombectomy. Mechanical thrombectomy was performed by neuro-interventionist, while IV rtPA, medical and neurologic assessment either clinically or by scales was made by the researcher. Baseline NIHSS, mRS was performed to assess patients condition before intervention. Complete laboratory investigations was performed, for all patients in the IV rtPA therapeutic time window (first 4.5 h) multimodal CT program was performed before intervention (CT, CT Angiography, CT Perfusion). For patients presented to us after that (> 4.5h) additional MRI DWI, PWI was done.
Patients was subgrouped into two major groups, Patients received IV rtPA and mechanical thrombectomy (bridging therapy) and patients had contraindication for IV rtPA or came after therapeutic time window and those received mechanical thrombectomy alone. Outcome measures was assessed by estimating NIHSS and mRS one week after intervention. Safety measures was evaluated by detecting the complications and mortality rates in every group. To detect impact of time on patients outcome we further subdivided the patients into 8 groups according to the time interval between symptoms onset and management. Statistical analysis was done, there were no statistically significant difference between general demographic characteristics between both groups.
We found that bridging therapy had better outcome, lower mortality rates than non bridging therapy. Although complications rates did not differ significantly between both groups, bridging therapy were associated with higher rates of cerebral hemorrhage. When the patients further subgrouped according to time of management perception we found that early intervention carried better prognosis, lower mortality rate than late intervention. The early bridging therapy was better than late bridging therapy, the early non bridging was better than late non bridging therapy, even the early non bridging therapy was better than late bridging therapy. Time had strong impact on outcome and mortality rate and had not any impact on complications rate.
We studied also the prognostic factors which could affect patients outcome after intervention and we found that successful recanalization of the vessel, NIHSS before intervention and intervention complications specifically pneumonia had the strongest impact on the outcome.
We compared our results to international publications and trials and found that our results is comparable to the trials performed by same stent retrieval as our (Solitaire stent) and better than trials performed by other stent retreivals. We had comparable successful recanalization rates, improvement rates, and mortality rates like the other trials.
However we had higher cerebral hemorrhage rates in both groups, especially in the bridging group. We think that this high hemorrhage rates may be due to local German guidelines which made heparin as obligatory treatment in post IV rtPA. Concerning impact of time on patients outcome, our results were similar to the international trials where stroke was mainly due to embolic cause (like us), and was not comparable to the trials where stroke was due to atherosclerosis and patients had good collaterals. Some of our prognostic factors were comparable to international trials and some were not. NIHSS at admission is the most potent prognostic factor, followed by recanalization rate.