Department of Neurology, Charité-University Medicine Berlin, Berlin, Germany.
Cerebrovasc Dis. 2013;35(3):250-6. doi: 10.1159/000347071. Epub 2013 Mar 26.
In acute ischemic stroke, brain imaging is mandatory in the decision whether to perform intravenous thrombolysis with recombinant tissue plasminogen activator. The most widespread used imaging modality to exclude intracranial hemorrhage is plain computed tomography (CT). However, there is an ongoing debate whether the information provided by magnetic resonance imaging (MRI) could improve the selection of patients for thrombolysis. We investigated whether the choice of imaging modality (MRI vs. CT) affects therapy safety and the patients' outcome.
Analyses are based on data from a prospective, single-center observational study that included all patients with acute ischemic stroke who received intravenous thrombolysis within 4.5 h. Stroke severity was assessed by the National Institutes of Health Stroke Scale. Safety was assessed by rates of symptomatic intracranial hemorrhage (SICH), brain edema with mass effect and 7-day mortality. Outcome was assessed at 3 months as mortality and proportion of independent patients (modified Rankin Scale score between 0 and 2).
We analyzed 345 patients of whom 141 received multimodal MRI and 204 received plain CT prior to treatment. Groups did not differ significantly in terms of age, neurological deficit, rate of elevated glucose level or rate of very high blood pressure. However, patients with CT-based thrombolysis had significantly higher rates of cardiac comorbidities (coronary artery disease, heart failure). In the MRI group, we observed a lower rate of 7-day mortality (1 vs. 10%; p = 0.001), a lower rate of SICH (1 vs. 6%; p = 0.010) and a nonsignificantly lower rate of brain edema with mass effect (2 vs. 6%; n.s.). In multivariable analysis, 7-day mortality was independently associated with MRI-based thrombolysis, even if cardiac comorbidities were taken into account. For mortality at 3 months, there was a nonsignificant difference in favor of the MRI group (16 vs. 23%; n.s.). In multivariable analyses, mortality at 3 months was independently associated with older age, higher stroke severity, brain edema with mass effect, SICH, pneumonia and coronary artery disease. Neither mortality nor independent outcome was influenced by initial imaging modality.
Thrombolysis based on multimodal MRI is associated with reduced rates of SICH and early death. Our results suggest that these complications affect survival principally in the acute phase after thrombolysis. However, nonneurological and especially cardiac comorbidities also influence survival after stroke and are underrepresented in stroke patients undergoing MRI. Selection bias has to be considered.
在急性缺血性脑卒中患者中，是否进行重组组织型纤溶酶原激活物静脉溶栓治疗，必须进行脑部影像学检查。最常用于排除颅内出血的影像学方法是平扫 CT。然而，目前仍在争论磁共振成像（MRI）提供的信息是否可以改善患者溶栓治疗的选择。我们研究了影像学方法（MRI 与 CT）的选择是否会影响治疗安全性和患者预后。
本分析基于一项前瞻性、单中心观察性研究的数据，该研究纳入了所有在 4.5 小时内接受静脉溶栓治疗的急性缺血性脑卒中患者。使用国立卫生研究院卒中量表评估卒中严重程度。通过症状性颅内出血（SICH）、有占位效应的脑水肿和 7 天死亡率评估安全性。使用死亡率和独立患者比例（改良 Rankin 量表评分 0-2 分）评估 3 个月的预后。
我们分析了 345 例患者，其中 141 例接受了多模态 MRI 检查，204 例接受了平扫 CT 检查。两组在年龄、神经功能缺损、血糖水平升高率或血压极高率方面无显著差异。然而，接受 CT 溶栓治疗的患者有显著更高的心脏合并症（冠状动脉疾病、心力衰竭）发生率。在 MRI 组，我们观察到 7 天死亡率较低（1%比 10%；p=0.001），SICH 发生率较低（1%比 6%；p=0.010），有占位效应的脑水肿发生率较低（2%比 6%；n.s.）。多变量分析显示，即使考虑到心脏合并症，7 天死亡率也与 MRI 溶栓治疗独立相关。3 个月的死亡率在 MRI 组有非显著性优势（16%比 23%；n.s.）。多变量分析显示，3 个月死亡率与年龄较大、卒中严重程度较高、有占位效应的脑水肿、SICH、肺炎和冠状动脉疾病独立相关。初始影像学方法既不影响死亡率，也不影响独立预后。
基于多模态 MRI 的溶栓治疗与 SICH 和早期死亡发生率降低相关。我们的结果表明，这些并发症主要在溶栓治疗后的急性期影响生存率。然而，非神经和特别是心脏合并症也会影响卒中后的生存率，且在接受 MRI 检查的卒中患者中代表性不足。需要考虑选择偏倚。
