Selection Of Stroke Patients Research Articles

Impact of Telemedicine on Acute Management of Stroke Patients Undergoing Endovascular Procedures

Background: Telemedicine is improving acute stroke care in remote areas. Delay in hospital-to-hospital transfer is a common reason why acute ischemic stroke patients are excluded from interventional therapy. The progressive implementation of these procedures, requiring highly specialized professionals in comprehensive stroke centers, will certainly challenge even more the geographic equity in the access to the best acute stroke treatments. We aimed to assess the benefits of telemedicine in selecting stroke patients for endovascular treatments. Methods: In our Reference Comprehensive Stroke Center (RCSC), we perform urgent intra-arterial procedures in acute stroke patients. Patients may be primarily admitted (PA) or referred from community hospitals with (TMHs; 2 centers) or without telemedicine (nonTMHs; 7 centers). We prospectively studied all consecutive stroke patients undergoing urgent endovascular recanalization procedures in the RCSC. We studied different outcome measures according to the patients’ initial admission: PA patients, TMH patients or nonTMH patients. For all patients, demographic and outcome data including serial National Institute of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) scores at 3 months were recorded. Clinical improvement was defined as a decrease ≥4 points on the NIHSS at 7 days or discharge and favorable outcome as mRS ≤2 at 3 months. Whether an endovascular procedure was indicated was decided according to clinical, radiological and transcranial Doppler (TCD) data, independently of the patient’s initial admission center. Results: During a 2-year period, 119 patients received endovascular treatment: PA patients 74 (63.1%), TMH patients 25 (20.5%), nonTM patients 20 (16.4%). The mean distance to the RCSC was 52 ± 15 km for TMHs and 34.5 ± 12 km for nonTMHs (p = 0.4). There were no differences in baseline characteristics including age (71, 71.6 and 66.5 years; p = 0.25), baseline NIHSS (18.5, 19 and 18; p = 0.57) and previous use of intravenous tissue plasminogen activator (56.5, 56.5 and 57.9%; p = 0.95). The rate of recanalization (modified Thrombolysis in Cerebral Infarction Score ≥2a) was similar in all groups (75, 66.6 and 68.4%; p = 0.682). TMH and PA patients had similar clinical improvement (61 vs. 63.8%; p = 0.51) and good functional outcome (36.8 vs. 35.3%; p = 0.722). Conversely, nonTMH patients presented a lesser degree of clinical improvement (31.3%) and poorer functional outcome (15.8%) than TMH (p = 0.019 and p = 0.046) and PA patients (p = 0.05 and p = 0.013). TMH patients had significantly shorter door-to-groin puncture times (47 vs. 69 min; p = 0.047). Conclusions: Telemedicine assessment to select patients for endovascular procedures improves the efficiency in stroke management and possibly the early and long-term outcome in patients receiving intra-arterial reperfusion treatment.

Selecting stroke patients for intra-arterial therapy

There is a great need for new treatments for acute ischemic stroke that will achieve greater rates of arterial recanalization and increase the population of patients who may benefit. Of several approaches under investigation, intra-arterial therapy (IAT) is the farthest along in clinical development, but experience has shown that the increased rates of recanalization achieved are not always translated to improved patient outcomes. Proper patient selection, allied to efficient strategies aiming at faster recanalization and reperfusion, may result in better clinical outcomes and more rational use of therapeutic resources. While high-tech multimodal imaging has the great promise of identifying hypoperfused but still viable brain tissue, a number of clues suggest that relatively low-tech approaches similar to those that were used to demonstrate the efficacy of systemic thrombolysis, and which have emphasized the key role of time and clinical factors such as age, glucose, stroke severity, and infarct on noncontrast CT scan, deserve greater study as an efficient way to optimize IAT. Eventually it will be a combination of predictors that will enable us to most precisely identify the best patients for IAT and any other new revascularization therapies.

Aggressive intervention to treat a young woman with intracranial hemorrhage following unsuccessful intravenous thrombolysis for left middle cerebral artery occlusion

Stroke patients whose condition does not improve after intravenous administration of tissue plasminogen activator (tPA) may be candidates for endovascular intervention. Patients with new intracerebral hemorrhage noted during such interventions pose a difficult challenge to neurointerventionists and are often sequestered as treatment failures and deemed inappropriate for intraarterial recanalization efforts. The authors present a case in which aggressive intervention was performed despite evidence of contrast extravasation on preintervention angiography. This 37-year-old woman presented with an occlusion of the M(1) segment of the left middle cerebral artery and a National Institutes of Health Stroke Scale score of 24. She received intravenous tPA without improvement. Angiography revealed M(1) thrombus as well as active contrast extravasation without arterial displacement. Thromboaspiration was performed in light of her known hemorrhage with excellent recanalization. Immediate postprocedure imaging demonstrated a large insular hematoma and emergent craniectomy and hematoma evacuation were performed. At 4 months' follow-up, the patient was living at home, was ambulating, and had excellent comprehension with mild expressive aphasia. There is little peer-reviewed data in the literature to aid in the decision-making process when contrast extravasation is recognized at the time of preinterevention angiography. Continuation of mechanical endovascular stroke intervention, in light of active contrast extravasation, may be warranted in young patients with major deficits and absence of arterial displacement or delayed global filling. Further thrombolytics are not advised. In select stroke patients, continuation of a planned attempt at mechanical recanalization without the further use of thrombolytics may be warranted in light of known intracerebral hemorrhage.

A brief prehospital stroke severity scale identifies ischemic stroke patients harboring persisting large arterial occlusions.

The Los Angeles Motor Scale (LAMS) is a brief 3-item stroke severity assessment measure designed for prehospital and Emergency Department use. The LAMS and NIHSS were scored in under-12-hour acute anterior circulation ischemic stroke patients. Stroke severity ratings were correlated with cervicocerebral vascular occlusion on CTA, MRA, and catheter angiography. Receiver operating curves, c statistics, and likelihood ratios were used to evaluate the predictive value for vascular occlusion of stroke severity ratings. Among 119 patients, mean age was 67 (+/-18), 45% were male. Time from onset to ED arrival was mean 190 minutes (range 10 to 660). Persisting large vessel occlusions (PLVOs) were present in 62% of patients. LAMS stroke severity scores were higher in patients harboring a vascular occlusion, median 5 (IQR 4 to 5) versus 2 (IQR 1 to 3). Similarly, NIHSS stroke severity scores were higher in PLVO patients, 19 (14 to 24) versus 5 (3 to 7). ROC curves demonstrated that the LAMS was highly effective in identifying patients with PLVOs, c statistic 0.854. At the optimal threshold of 4 or higher, LAMS scores showed sensitivity 0.81, specificity 0.89, and overall accuracy 0.85. LAMS performance was comparable to NIHSS performance (c statistic 0.933). The positive likelihood ratio associated with a LAMS score > or = 4 was 7.36 and the negative likelihood ratio 0.21. Stroke severity assessed by the LAMS predicts presence of large artery anterior circulation occlusion with high sensitivity and specificity. The LAMS is a promising instrument for use by prehospital personnel to identify select stroke patients for direct transport to Comprehensive Stroke Centers capable of endovascular interventions.

Cost-Effectiveness of Echocardiography to Identify Intracardiac Thrombus among Patients with First Stroke or Transient Ischemic Attack

Echocardiography to select stroke patients for targeted treatments, such as anticoagulation (AC), to reduce recurrent stroke risk is controversial. The authors' objective was to evaluate the cost-effectiveness of imaging strategies that use transthoracic (TTE) and transesophageal (TEE) echocardiography for identifying intracardiac thrombus in new stroke patients. Model-based cost-effectiveness analysis of 7 echocardiographic imaging strategies and 2 nontesting strategies with model parameters based on systematic evidence review related to effectiveness of echocardiography in newly diagnosed ischemic stroke patients (white males aged 65 years in base case). Primary outcome was cost per quality-adjusted life year (QALY). All strategies containing TTE were dominated by others and were eliminated from the analysis. Assuming that AC reduces recurrent stroke risk from intracardiac thrombus by 43% over 1 year, TEE generated a cost per QALY of $137,000 (relative to standard treatment) among patients with 5% thrombus prevalence. Cost per QALY dropped to $50,000 in patients with at least 15% intracardiac thrombus prevalence, or, if an 86% relative risk reduction with AC is assumed, in patients with thrombus prevalence of at least 6%. Probabilistic analyses indicate considerable uncertainty around the cost-effectiveness of echocardiography across a wide range of intracardiac thrombus prevalence (pretest probability). Current evidence on cost-effectiveness is insufficient to justify widespread use of echocardiography in stroke patients. Additional research on recurrent stroke risk in patients with intracardiac thrombus and on the efficacy of AC in reducing that risk may contribute to a better understanding of the circumstances under which echocardiography will be cost-effective.

Comparison of CT perfusion and angiography and MRI in selecting stroke patients for acute treatment

Forty-two stroke patients successively underwent perfusion CT (PCT)/CT angiography (CTA) and MRI examinations within 3 to 9 hours following symptom onset; 14 would have been suitable candidates for reperfusion treatment based on MRI findings. Correlation between PCT/CTA and MRI was excellent for infarct size, cortical involvement, and internal cerebral artery occlusion and substantial for penumbra/infarct ratio. Relying on MRI or PCT/CTA would have led to the same treatment decisions in all cases but one.

Clinical and Transthoracic Echocardiographic Predictors of Abnormal Transesophageal Findings in Patients with Suspected Cardiac Source of Embolism

Approximately 20% of cerebral infarctions are caused by a cardiac source of embolism. Although transesophageal echocardiography (TEE) is a valuable tool for evaluating patients with suspected cardioembolism, its use should be more selective. We attempted to determine whether risk factors derived from the clinical, ECG, and transthoracic echocardiogram (TTE) would make TEE use more selective and increase its yield. We retrospectively reviewed the records of 108 patients with suspected embolic stroke who had undergone TEE evaluation. We defined the presence of left atrial appendage spontaneous contrast (LAASC), left atrial appendage thrombus (LAAT), patent foramen ovale (PFO), or intraatrial septal aneurysm (IASA) as TEE endpoints suggestive of cardioembolism. We evaluated the association between the TEE endpoints and (1) age greater than 60 years, (2) the presence of atrial flutter (AFl) or atrial fibrillation (AF) on ECG, (3) left ventricular (LV) dysfunction by TTE (mild, LVEF < 40%; severe, LVEF < 25%), and (4) left atrial (LA) size > 4 cm also determined by TTE. The statistical analysis performed was one-way analysis of variance controlling for interactions between different risk factors and the endpoints. RESULTS The strongest independent predictors for the presence of LAASC or LAAT were age greater than 60 years, presence of AFl/AF, and LV systolic dysfunction. There was no association between any of the risk factors with the presence of PFO or IASA. This study demonstrates that clinical characteristics, ECG, and TTE findings can help to better select stroke patients for TEE. Future larger studies are needed to provide more supporting data.

Anticoagulant therapy for progressing strokes; a guide for patient selection.

The success of anticoagulant therapy for progressing strokes depends on the earliest possible treatment, but first strokes due to intracranial hemorrhage must be excluded. A guide for selecting stroke patients most likely to benefit from immediate anticoagulant therapy and an illustrative case are presented and discussed.